Squashed 'third_party/allwpilib/' changes from f1a82828fe..ce550705d7

ce550705d7 [ntcore] Fix client "received unknown id -1" (#6186)
3989617bde [ntcore] NetworkTable::GetStruct: Add I template param (#6183)
f1836e1321 [fieldImages] Fix 2024 field json (#6179)
d05f179a9a [build] Fix running apriltagsvision Java example (#6173)
b1b03bed85 [wpilib] Update MotorControllerGroup deprecation message (#6171)
fa63fbf446 LICENSE.md: Bump year to 2024 (#6169)
4809f3d0fc [apriltag] Add 2024 AprilTag locations (#6168)
dd90965362 [wpiutil] Fix RawFrame.setInfo() NPE (#6167)
8659372d08 [fieldImages] Add 2024 field image (#6166)
a2e4d0b15d [docs] Fix docs for SysID routine (#6164)
0a46a3a618 [wpilib] Make ADXL345 default I2C address public (#6163)
7c26bc70ab [sysid] Load DataLog files directly for analysis (#6103)
f94e3d81b9 [docs] Fix SysId routine JavaDoc warnings (#6159)
6bed82a18e [wpilibc] Clean up C++ SysId routine (#6160)
4595f84719 [wpilib] Report LiveWindow-enabled-in-test (#6158)
707cb06105 [wpilib] Add SysIdRoutine logging utility and command factory (#6033)
3e40b9e5da [wpilib] Correct SmartDashboard usage reporting (#6157)
106518c3f8 [docs] Fix wpilibj JavaDoc warnings (#6154)
19cb2a8eb4 [wpilibj] Make class variables private to match C++ (#6153)
13f4460e00 [docs] Add missing docs to enum fields (NFC) (#6150)
4210f5635d [docs] Fix warnings about undocumented default constructors (#6151)
0f060afb55 [ntcore] Disable WebSocket fragmentation (#6149)
f29a7d2e50 [docs] Add missing JavaDocs (#6146)
6e58db398d [commands] Make Java fields private (#6148)
4ac0720385 [build] Clean up CMake files (#6141)
44db3e0ac0 [sysid] Make constexpr variables outside class scope inline (#6145)
73c7d87db7 [glass] NTStringChooser: Properly set retained (#6144)
25636b712f [build] Remove unnecessary native dependencies in wpilibjExamples (#6143)
01fb98baaa [docs] Add Missing JNI docs from C++ (NFC) (#6139)
5c424248c4 [wpilibj] Remove unused AnalogTriggerException (#6142)
c486972c55 [wpimath] Make ExponentialProfile.State mutable (#6138)
783acb9b72 [wpilibj] Store long preferences as integers (#6136)
99ab836894 [wpiutil] Add missing JavaDocs (NFC) (#6132)
ad0859a8c9 [docs] Add missing JavaDocs (#6125)
5579219716 [docs] Exclude quickbuf files and proto/struct packages from doclint (#6128)
98f06911c7 [sysid] Use eigenvector component instead of eigenvalue for fit quality check (#6131)
e1d49b975c [wpimath] Add LinearFilter reset() overload to initialize input and output buffers (#6133)
8a0bf2b7a4 [hal] Add CANAPITypes to java (#6121)
91d8837c11 [wpilib] Make protected fields in accelerometers/gyros private (#6134)
e7c9f27683 [wpilib] Add functional interface equivalents to MotorController (#6053)
8aca706217 [glass] Add type information to SmartDashboard menu (#6117)
7d3e4ddba9 [docs] Add warning about using user button to docs (NFC) (#6129)
ec3cb3dcba [build] Disable clang-tidy warning about test case names (#6127)
495585b25d [examples] Update april tag family to 36h11 (#6126)
f9aabc5ab2 [wpilib] Throw early when EventLoop is modified while running (#6115)
c16946c0ec [hal] Add CANJNI docs (NFC) (#6120)
b7f4eb2811 [doc] Update maven artifacts for units and apriltags (NFC) (#6123)
f419a62b38 [doc] Update maintainers.md (NFC) (#6124)
938bf45fd9 [wpiutil] Remove type param from ProtobufSerializable and StructSerializable (#6122)
c34debe012 [docs] Link to external OpenCV docs (#6119)
07183765de [hal] Fix formatting of HAL_ENUM enums (NFC) (#6114)
af46034b7f [wpilib] Document only first party controllers are guaranteed to have correct mapping (#6112)
636ef58d94 [hal] Properly error check readCANStreamSession (#6108)
cc631d2a69 [build] Fix generated source set location in the HAL (#6113)
09f76b32c2 [wpimath] Compile with UTF-8 encoding (#6111)
47c5fd8620 [sysid] Check data quality before OLS (#6110)
24a76be694 [hal] Add method to detect if the CAN Stream has overflowed (#6105)
9333951736 [hal] Allocate CANStreamMessage in JNI if null (#6107)
6a2d3c30a6 [wpiutil] Struct: Add info template parameter pack (#6086)
e07de37e64 [commands] Mark ParallelDeadlineGroup.setDeadline() final (#6102)
141241d2d6 [wpilib] Fix usage reporting for static classes (#6090)
f2c2bab7dc [sysid] Fix adjusted R² calculation (#6101)
5659038443 [wpiutil,cscore,apriltag] Fix RawFrame (#6098)
8aeee03626 [commands] Improve error message when composing commands twice in same composition (#6091)
55508706ff [wpiutil,cscore] Move VideoMode.PixelFormat to wpiutil (#6097)
ab78b930e9 [wpilib] ADIS16470: Add access to all 3 axes (#6074)
795d4be9fd [wpilib] Fix precision issue in Color round-and-clamp (#6100)
7aa9ad44b8 [commands] Deprecate C++ TransferOwnership() (#6095)
92c81d0791 [ci] Update pregenerate workflow to actions/checkout@v4 (#6094)
1ce617be07 [ci] Update artifact actions to v4 (#6092)
2441b57156 [wpilib] Add PWMSparkFlex MotorController (#6089)
21d1972d7a [wpiutil] DataLog: Ensure file is written on shutdown (#6087)
c29e8c66cf [wpiutil] DataLog: Fix UB in AppendImpl (#6088)
ab309e34ef [glass] Fix order of loading window settings (#6056)
22a322c9f3 [wpimath] Report error on negative PID gains (#6055)
1dba26c937 [wpilib] Add method to get breaker fault at a specific channel in PowerDistribution[Sticky]Faults (#5521)
ef1cb3f41e [commands] Fix compose-while-scheduled issue and test all compositions (#5581)
aeb1a4aa33 [wpiutil] Add serializable marker interfaces (#6060)
c1178d5add [wpilib] Add StadiaController and command wrapper (#6083)
4e4a468d4d [wpimath] Make feedforward classes throw exceptions for negative Kv or Ka (#6084)
d1793f077d [build] cmake: Add NO_WERROR option to disable -Werror (#6071)
43fb6e9f87 [glass] Add Profiled PID controller support & IZone Support (#5959)
bcef6c5398 [apriltag] Fix Java generation functions (#6063)
4059e0cd9f [hal,wpilib] Add function to control "Radio" LED (#6073)
0b2cfb3abc [dlt] Change datalogtool default folder to logs folder (#6079)
df5e439b0c [wpilib] PS4Controller: enable usage reporting (#6081)
0ff7478968 [cscore] Fix RawFrame class not being loaded in JNI (#6077)
6f23d32fe1 [wpilib] AddressableLED: Update warning about single driver (NFC) (#6069)
35a1c52788 [build] Upgrade quickbuf to 1.3.3 (#6072)
e4e2bafdb1 [sysid] Document timestamp units (#6065)
3d201c71f7 [ntcore] Fix overlapping subscriber handling (#6067)
f02984159f [glass] Check for null entries when updating struct/proto (#6059)
a004c9e05f [commands] SubsystemBase: allow setting name in constructor (#6052)
0b4c6a1546 [wpimath] Add more docs to SimulatedAnnealing (NFC) (#6054)
ab15dae887 [wpilib] ArcadeDrive: Fix max output handling (#6051)
9599c1f56f [hal] Add usage reporting ids from 2024v2 image (#6041)
f87c64af8a [wpimath] MecanumDriveWheelSpeeds: Fix desaturate() (#6040)
8798700cec [wpilibcExamples] Add inline specifier to constexpr constants (#6049)
85c9ae6eff [wpilib] Fix PS5 Controller mappings (#6050)
7c8b7a97ad [wpiutil] Zero out roborio system timestamp (#6042)
d9b504bc84 [wpilib] DataLogManager: Change sim location to logs subdir (#6039)
906b810136 [build] cmake: Fix ntcore generated header install (#6038)
56e5b404d1 Update to final 2024 V2 image (#6034)
8723ee5c39 [ntcore] Add cached topic property (#5494)
192a28af47 Fix JDK 21 warnings (#6028)
d40bdd70ba [build] Upgrade to spotbugs Gradle plugin 6.0.2 (#6027)
7bfadf32e5 [wpilibj] Joystick: make remainder of get axis methods final (#6024)
a770110438 [commands] CommandCompositionError: Include stacktrace of original composition (#5984)
54a55b8b53 [wpiutil,hal] Update image; init Rio Now() HMB with a FPGA session (#6016)
7d4e515a6b [wpimath] Simplify calculation of C for DARE precondition (#6022)
5200316c14 [ntcore] Update transmit period on topic add/remove (#6021)
ddf79a25d4 [wpiunits] Overload Measure.per(Time) to return Measure<Velocity> (#6018)
a71adef316 [wpiutil] Clean up circular_buffer iterator syntax (#6020)
39a0bf4b98 [examples] Call resetOdometry() when controller command is executed (#5905)
f5fc101fda [build] cmake: Export jars and clean up jar installs (#6014)
38bf024c96 [build] Update to Gradle 8.5 (#6007)
9d11544c18 [wpimath] Rotate traveling salesman solution so input and solution have same initial pose (#6015)
28deba20f5 [wpimath] Commit generated quickbuf Java files (#5994)
c2971c0bb3 [build] cmake: Export apriltag and wpimath (#6012)
41cfc961e4 gitattributes: Add linguist-generated locations (#6004)
14c3ade155 [wpimath] Struct cleanup (#6011)
90757b9e90 [wpilib] Make Color::HexString() constexpr (#5985)
2676b77873 Fix compilation issues that occur when building with bazel (#6008)
d32c10487c [examples] Update C++ examples to use CommandPtr (#5988)
9bc5fcf886 [build] cmake: Default WITH_JAVA_SOURCE to WITH_JAVA (#6005)
d431abba3b [upstream_utils] Fix GCEM namespace usage and add hypot(x, y, z) (#6002)
2bb1409b82 Clean up Java style (#5990)
66172ab288 Remove submodule (#6003)
e8f8c0ceb0 [upstream_utils] Update to latest Eigen HEAD (#5996)
890992a849 [hal] Commit generated usage reporting files (#5993)
a583ca01e1 [wpiutil] Change Struct to allow non-constexpr implementation (#5992)
ca272de400 [build] Fix Gradle compile_commands.json and clang-tidy warnings (#5977)
76ae090570 [wpiutil] type_traits: Add is_constexpr() (#5997)
5172ab8fd0 [commands] C++ CommandPtr: Prevent null initialization (#5991)
96914143ba [build] Bump native-utils to fix compile_commands.json (#5989)
464e6121ef [ci] Report failed status to Azure on failed tests (#2654)
5dad46cd45 [wpimath] Commit generated files (#5986)
54ab65a63a [ntcore] Commit generated files (#5962)
7ed900ae3a [wpilib] Add hex string constructor to Color and Color8Bit (#5063)
74b85b76a9 [wpimath] Make gcem call std functions if not constant-evaluated (#5983)
30816111db [wpimath] Fix TimeInterpolatableBuffer crash (#5972)
5cc923de33 [wpilib] DataLogManager: Use logs subdirectory on USB drives (#5975)
1144115da0 [commands] Add GetName to Subsystem, use in Scheduler tracer epochs (#5836)
ac7d726ac3 [wpimath] Add simulated annealing (#5961)
e09be72ee0 [wpimath] Remove unused SimpleMatrixUtils class (#5979)
0f9ebe92d9 [wpimath] Add generic circular buffer class to Java (#5969)
9fa28eb07a [ci] Bump actions/checkout to v4 (#5736)
ca684ac207 [hal] Add capability to read power distribution data as a stream (#4983)
51eecef2bd [wpimath] Optimize 2nd derivative of quintic splines (#3292)
4fcf0b25a1 [build] Apply a formatter for CMake files (#5973)
9b8011aa67 [build] Pin wpiformat version (#5982)
e00a0e84c1 [build] cmake: fix protobuf dependency finding for certain distributions (#5981)
23dd591394 [upstream_utils] Remove libuv patch that adjusts whitespace (#5976)
b0719942f0 [wpiutil] Timestamp: Report errors on Rio HMB init failure (#5974)
7bc89c4322 [wpilib] Update getAlliance() docs (NFC) (#5971)
841ea682d1 [upstream_utils] Upgrade to LLVM 17.0.5 (#5970)
a74db52dae [cameraserver] Add getVideo() pixelFormat overload (#5966)
a7eb422662 [build] Update native utils for new compile commands files (#5968)
544b231d4d [sysid] Add missing cassert include (#5967)
31cd015970 [wpimath] Add SysId doc links to LinearSystemId in C++ (NFC) (#5960)
9280054eab Revert "[build] Export wpimath protobuf symbols (#5952)"
2aba97c610 Export pb files from wpimath
c80b2d2017 [build] Export wpimath protobuf symbols (#5952)
3c0652c18a [cscore] Replace CS_PixelFormat with WPI_PixelFormat (#5954)
95716eb0cb [wpiunits] Documentation improvements (#5932)
423fd75fa8 [wpilib] Default LiveWindowEnabledInTest to false (#5950)
dfdea9c992 [wpimath] Make KalmanFilter variant for asymmetric updates (#5951)
ca81ced409 [wpiutil] Move RawFrame to wpiutil; add generation of RawFrame for AprilTags (#5923)
437cc91af5 [cscore] CvSink: Allow specifying output PixelFormat (#5943)
25b7dca46b [build] Remove CMake flat install option (#5944)
bb05e20247 [wpimath] Add protobuf/struct for trivial types (#5935)
35744a036e [wpimath] Move struct/proto classes to separate files (#5918)
80d7ad58ea [build] Declare platform launcher dependency explicitly (#5909)
f8d983b154 [ntcore] Protobuf/Struct: Use atomic_bool instead of atomic_flag (#5946)
4a44210ee3 [ntcore] NetworkTableInstance: Suppress unused lambda capture warning (#5947)
bdc8620d55 [upstream_utils] Fix fmt compilation errors on Windows (#5948)
0ca1e9b5f9 [wpimath] Add basic wpiunits support (#5821)
cc30824409 [ntcore] Increase client meta-topic decoding limit (#5934)
b1fad062f7 [wpilib] Use RKDP in DifferentialDrivetrainSim (#5931)
ead9ae5a69 [build] Add generateProto dependency to test and dev (#5933)
cfbff32185 [wpiutil] timestamp: Fix startup race on Rio (#5930)
7d90d0bcc3 [wpimath] Clean up StateSpaceUtil (#5891)
7755e45aac [build] Add generated protobuf headers to C++ test include path (#5926)
3985c031da [ntcore] ProtobufSubscriber: Fix typos (#5928)
7a87fe4b60 [ntcore] ProtobufSubscriber: Make mutex and msg mutable (#5927)
09f3ed6a5f [commands] Add static Trigger factories for robot mode changes (#5902)
79dd795bc0 [wpimath] Clean up VecBuilder and MatBuilder (#5906)
e117274a67 [wpilib] Change default Rio log dir from /home/lvuser to /home/lvuser/logs (#5899)
a8b80ca256 [upstream_utils] Update to libuv 1.47.0 (#5889)
b3a9c3e96b [build] Bump macOS deployment target to 12 (#5890)
0f8129677b [build] Distribute wpimath protobuf headers (#5925)
d105f9e3e9 [wpiutil] ProtobufBuffer: Fix buffer reallocation (#5924)
c5f2f6a0fb [fieldImages] Fix typo in field images artifact name (#5922)
c1a57e422a [commands] Clean up make_vector.h (#5917)
78ebc6e9ec [wpimath] change G to gearing in LinearSystemId factories (#5834)
9ada181866 [hal] DriverStation.h: Add stddef.h include (#5897)
95fa5ec72f [wpilibc,ntcoreffi] DataLogManager: join on Stop() call (#5910)
b6f2d3cc14 [build] Remove usage of Version.parse (#5911)
cc2cbeb04c [examples] Replace gyro rotation with poseEstimator rotation (#5900)
fa6b171e1c [wpiutil] Suppress protobuf warning false positives on GCC 13 (#5907)
d504639bbe [apriltag] Improve AprilTag docs (#5895)
3a1194be40 Replace static_cast<void>() with [[maybe_unused]] attribute (#5892)
70392cbbcb [build] cmake: Add protobuf dependency to wpiutil-config (#5886)
17c1bd5a83 [ntcore] Use json_fwd (#5881)
e69a9efeba [wpilibcExamples] Match array parameter bounds (#5880)
14dcd0d26f Use char instead of uint8_t for json::parse (#5877)
ec1d261984 [hal] Fix garbage data for match info before DS connection (#5879)
63dbf5c614 [wpiutil] MemoryBuffer: Fix normal read and file type check (#5875)
b2e7be9250 [ntcore] Only datalog meta-topics if specifically requested (#5873)
201a42a3cd [wpimath] Reorder TrapezoidProfile.calculate() arguments (#5874)
04a781b4d7 [apriltag] Add GetTags to C++ version of AprilTagFieldLayout (#5872)
87a8a1ced4 [docs] Exclude eigen and protobuf from doxygen (#5871)

git-subtree-dir: third_party/allwpilib
git-subtree-split: ce550705d7cdab117c0153a202973fc026a81274
Signed-off-by: Maxwell Henderson <mxwhenderson@gmail.com>
Change-Id: Ic8645d0551d62b411b0a816c493f0f33291896a1
diff --git a/sysid/src/main/native/cpp/App.cpp b/sysid/src/main/native/cpp/App.cpp
index 947ea43..4a60f79 100644
--- a/sysid/src/main/native/cpp/App.cpp
+++ b/sysid/src/main/native/cpp/App.cpp
@@ -24,21 +24,20 @@
 #include <wpigui_openurl.h>
 
 #include "sysid/view/Analyzer.h"
-#include "sysid/view/JSONConverter.h"
-#include "sysid/view/Logger.h"
+#include "sysid/view/DataSelector.h"
+#include "sysid/view/LogLoader.h"
 #include "sysid/view/UILayout.h"
 
 namespace gui = wpi::gui;
 
 static std::unique_ptr<glass::WindowManager> gWindowManager;
 
-glass::Window* gLoggerWindow;
+glass::Window* gLogLoaderWindow;
+glass::Window* gDataSelectorWindow;
 glass::Window* gAnalyzerWindow;
 glass::Window* gProgramLogWindow;
 static glass::MainMenuBar gMainMenu;
 
-std::unique_ptr<sysid::JSONConverter> gJSONConverter;
-
 glass::LogData gLog;
 wpi::Logger gLogger;
 
@@ -103,11 +102,23 @@
   gWindowManager = std::make_unique<glass::WindowManager>(storage);
   gWindowManager->GlobalInit();
 
-  gLoggerWindow = gWindowManager->AddWindow(
-      "Logger", std::make_unique<sysid::Logger>(storage, gLogger));
+  auto logLoader = std::make_unique<sysid::LogLoader>(storage, gLogger);
+  auto dataSelector = std::make_unique<sysid::DataSelector>(storage, gLogger);
+  auto analyzer = std::make_unique<sysid::Analyzer>(storage, gLogger);
 
-  gAnalyzerWindow = gWindowManager->AddWindow(
-      "Analyzer", std::make_unique<sysid::Analyzer>(storage, gLogger));
+  logLoader->unload.connect([ds = dataSelector.get()] { ds->Reset(); });
+  dataSelector->testdata = [_analyzer = analyzer.get()](auto data) {
+    _analyzer->m_data = data;
+    _analyzer->AnalyzeData();
+  };
+
+  gLogLoaderWindow =
+      gWindowManager->AddWindow("Log Loader", std::move(logLoader));
+
+  gDataSelectorWindow =
+      gWindowManager->AddWindow("Data Selector", std::move(dataSelector));
+
+  gAnalyzerWindow = gWindowManager->AddWindow("Analyzer", std::move(analyzer));
 
   gProgramLogWindow = gWindowManager->AddWindow(
       "Program Log", std::make_unique<glass::LogView>(&gLog));
@@ -115,10 +126,16 @@
   // Set default positions and sizes for windows.
 
   // Logger window position/size
-  gLoggerWindow->SetDefaultPos(sysid::kLoggerWindowPos.x,
-                               sysid::kLoggerWindowPos.y);
-  gLoggerWindow->SetDefaultSize(sysid::kLoggerWindowSize.x,
-                                sysid::kLoggerWindowSize.y);
+  gLogLoaderWindow->SetDefaultPos(sysid::kLogLoaderWindowPos.x,
+                                  sysid::kLogLoaderWindowPos.y);
+  gLogLoaderWindow->SetDefaultSize(sysid::kLogLoaderWindowSize.x,
+                                   sysid::kLogLoaderWindowSize.y);
+
+  // Data selector window position/size
+  gDataSelectorWindow->SetDefaultPos(sysid::kDataSelectorWindowPos.x,
+                                     sysid::kDataSelectorWindowPos.y);
+  gDataSelectorWindow->SetDefaultSize(sysid::kDataSelectorWindowSize.x,
+                                      sysid::kDataSelectorWindowSize.y);
 
   // Analyzer window position/size
   gAnalyzerWindow->SetDefaultPos(sysid::kAnalyzerWindowPos.x,
@@ -133,8 +150,6 @@
                                     sysid::kProgramLogWindowSize.y);
   gProgramLogWindow->DisableRenamePopup();
 
-  gJSONConverter = std::make_unique<sysid::JSONConverter>(gLogger);
-
   // Configure save file.
   gui::ConfigurePlatformSaveFile("sysid.ini");
 
@@ -157,15 +172,6 @@
       ImGui::EndMenu();
     }
 
-    bool toCSV = false;
-    if (ImGui::BeginMenu("JSON Converters")) {
-      if (ImGui::MenuItem("JSON to CSV Converter")) {
-        toCSV = true;
-      }
-
-      ImGui::EndMenu();
-    }
-
     if (ImGui::BeginMenu("Docs")) {
       if (ImGui::MenuItem("Online documentation")) {
         wpi::gui::OpenURL(
@@ -178,19 +184,6 @@
 
     ImGui::EndMainMenuBar();
 
-    if (toCSV) {
-      ImGui::OpenPopup("SysId JSON to CSV Converter");
-      toCSV = false;
-    }
-
-    if (ImGui::BeginPopupModal("SysId JSON to CSV Converter")) {
-      gJSONConverter->DisplayCSVConvert();
-      if (ImGui::Button("Close")) {
-        ImGui::CloseCurrentPopup();
-      }
-      ImGui::EndPopup();
-    }
-
     if (about) {
       ImGui::OpenPopup("About");
       about = false;
diff --git a/sysid/src/main/native/cpp/analysis/AnalysisManager.cpp b/sysid/src/main/native/cpp/analysis/AnalysisManager.cpp
index b15cae8..be88b57 100644
--- a/sysid/src/main/native/cpp/analysis/AnalysisManager.cpp
+++ b/sysid/src/main/native/cpp/analysis/AnalysisManager.cpp
@@ -5,24 +5,39 @@
 #include "sysid/analysis/AnalysisManager.h"
 
 #include <cmath>
-#include <cstddef>
 #include <functional>
-#include <stdexcept>
 
 #include <fmt/format.h>
 #include <units/angle.h>
-#include <units/math.h>
+#include <wpi/MathExtras.h>
 #include <wpi/MemoryBuffer.h>
 #include <wpi/StringExtras.h>
 #include <wpi/StringMap.h>
 
-#include "sysid/Util.h"
 #include "sysid/analysis/FilteringUtils.h"
-#include "sysid/analysis/JSONConverter.h"
-#include "sysid/analysis/TrackWidthAnalysis.h"
 
 using namespace sysid;
 
+static double Lerp(units::second_t time,
+                   std::vector<MotorData::Run::Sample<double>>& data) {
+  auto next = std::find_if(data.begin(), data.end(), [&](const auto& entry) {
+    return entry.time > time;
+  });
+
+  if (next == data.begin()) {
+    next++;
+  }
+
+  if (next == data.end()) {
+    next--;
+  }
+
+  const auto prev = next - 1;
+
+  return wpi::Lerp(prev->measurement, next->measurement,
+                   (time - prev->time) / (next->time - prev->time));
+}
+
 /**
  * Converts a raw data vector into a PreparedData vector with only the
  * timestamp, voltage, position, and velocity fields filled out.
@@ -38,18 +53,25 @@
  *
  * @return A PreparedData vector
  */
-template <size_t S, size_t Timestamp, size_t Voltage, size_t Position,
-          size_t Velocity>
-static std::vector<PreparedData> ConvertToPrepared(
-    const std::vector<std::array<double, S>>& data) {
+static std::vector<PreparedData> ConvertToPrepared(const MotorData& data) {
   std::vector<PreparedData> prepared;
-  for (int i = 0; i < static_cast<int>(data.size()) - 1; ++i) {
-    const auto& pt1 = data[i];
-    const auto& pt2 = data[i + 1];
-    prepared.emplace_back(PreparedData{
-        units::second_t{pt1[Timestamp]}, pt1[Voltage], pt1[Position],
-        pt1[Velocity], units::second_t{pt2[Timestamp] - pt1[Timestamp]}});
+  // assume we've selected down to a single contiguous run by this point
+  auto run = data.runs[0];
+
+  for (int i = 0; i < static_cast<int>(run.voltage.size()) - 1; ++i) {
+    const auto& currentVoltage = run.voltage[i];
+    const auto& nextVoltage = run.voltage[i + 1];
+
+    auto currentPosition = Lerp(currentVoltage.time, run.position);
+
+    auto currentVelocity = Lerp(currentVoltage.time, run.velocity);
+
+    prepared.emplace_back(PreparedData{currentVoltage.time,
+                                       currentVoltage.measurement.value(),
+                                       currentPosition, currentVelocity,
+                                       nextVoltage.time - currentVoltage.time});
   }
+
   return prepared;
 }
 
@@ -62,18 +84,16 @@
  *
  * @param dataset A reference to the dataset being used
  */
-template <size_t S>
-static void CopyRawData(
-    wpi::StringMap<std::vector<std::array<double, S>>>* dataset) {
+static void CopyRawData(wpi::StringMap<MotorData>* dataset) {
   auto& data = *dataset;
   // Loads the Raw Data
   for (auto& it : data) {
     auto key = it.first();
-    auto& dataset = it.getValue();
+    auto& motorData = it.getValue();
 
     if (!wpi::contains(key, "raw")) {
-      data[fmt::format("raw-{}", key)] = dataset;
-      data[fmt::format("original-raw-{}", key)] = dataset;
+      data[fmt::format("raw-{}", key)] = motorData;
+      data[fmt::format("original-raw-{}", key)] = motorData;
     }
   }
 }
@@ -94,416 +114,73 @@
 }
 
 void AnalysisManager::PrepareGeneralData() {
-  using Data = std::array<double, 4>;
-  wpi::StringMap<std::vector<Data>> data;
   wpi::StringMap<std::vector<PreparedData>> preparedData;
 
-  // Store the raw data columns.
-  static constexpr size_t kTimeCol = 0;
-  static constexpr size_t kVoltageCol = 1;
-  static constexpr size_t kPosCol = 2;
-  static constexpr size_t kVelCol = 3;
-
-  WPI_INFO(m_logger, "{}", "Reading JSON data.");
-  // Get the major components from the JSON and store them inside a StringMap.
-  for (auto&& key : AnalysisManager::kJsonDataKeys) {
-    data[key] = m_json.at(key).get<std::vector<Data>>();
-  }
-
   WPI_INFO(m_logger, "{}", "Preprocessing raw data.");
-  // Ensure that voltage and velocity have the same sign. Also multiply
-  // positions and velocities by the factor.
-  for (auto it = data.begin(); it != data.end(); ++it) {
-    for (auto&& pt : it->second) {
-      pt[kVoltageCol] = std::copysign(pt[kVoltageCol], pt[kVelCol]);
-      pt[kPosCol] *= m_factor;
-      pt[kVelCol] *= m_factor;
-    }
-  }
 
   WPI_INFO(m_logger, "{}", "Copying raw data.");
-  CopyRawData(&data);
+  CopyRawData(&m_data.motorData);
 
   WPI_INFO(m_logger, "{}", "Converting raw data to PreparedData struct.");
   // Convert data to PreparedData structs
-  for (auto& it : data) {
+  for (auto& it : m_data.motorData) {
     auto key = it.first();
-    preparedData[key] =
-        ConvertToPrepared<4, kTimeCol, kVoltageCol, kPosCol, kVelCol>(
-            data[key]);
+    preparedData[key] = ConvertToPrepared(m_data.motorData[key]);
+    WPI_INFO(m_logger, "SAMPLES {}", preparedData[key].size());
   }
 
   // Store the original datasets
-  m_originalDataset[static_cast<int>(
-      AnalysisManager::Settings::DrivetrainDataset::kCombined)] =
-      CombineDatasets(preparedData["original-raw-slow-forward"],
-                      preparedData["original-raw-slow-backward"],
-                      preparedData["original-raw-fast-forward"],
-                      preparedData["original-raw-fast-backward"]);
+  m_originalDataset =
+      CombineDatasets(preparedData["original-raw-quasistatic-forward"],
+                      preparedData["original-raw-quasistatic-reverse"],
+                      preparedData["original-raw-dynamic-forward"],
+                      preparedData["original-raw-dynamic-reverse"]);
 
   WPI_INFO(m_logger, "{}", "Initial trimming and filtering.");
   sysid::InitialTrimAndFilter(&preparedData, &m_settings, m_positionDelays,
                               m_velocityDelays, m_minStepTime, m_maxStepTime,
-                              m_unit);
+                              m_data.distanceUnit);
+
+  WPI_INFO(m_logger, "{}", m_minStepTime);
+  WPI_INFO(m_logger, "{}", m_maxStepTime);
 
   WPI_INFO(m_logger, "{}", "Acceleration filtering.");
   sysid::AccelFilter(&preparedData);
 
   WPI_INFO(m_logger, "{}", "Storing datasets.");
   // Store the raw datasets
-  m_rawDataset[static_cast<int>(
-      AnalysisManager::Settings::DrivetrainDataset::kCombined)] =
-      CombineDatasets(
-          preparedData["raw-slow-forward"], preparedData["raw-slow-backward"],
-          preparedData["raw-fast-forward"], preparedData["raw-fast-backward"]);
+  m_rawDataset = CombineDatasets(preparedData["raw-quasistatic-forward"],
+                                 preparedData["raw-quasistatic-reverse"],
+                                 preparedData["raw-dynamic-forward"],
+                                 preparedData["raw-dynamic-reverse"]);
 
   // Store the filtered datasets
-  m_filteredDataset[static_cast<int>(
-      AnalysisManager::Settings::DrivetrainDataset::kCombined)] =
-      CombineDatasets(
-          preparedData["slow-forward"], preparedData["slow-backward"],
-          preparedData["fast-forward"], preparedData["fast-backward"]);
+  m_filteredDataset = CombineDatasets(
+      preparedData["quasistatic-forward"], preparedData["quasistatic-reverse"],
+      preparedData["dynamic-forward"], preparedData["dynamic-reverse"]);
 
-  m_startTimes = {preparedData["raw-slow-forward"][0].timestamp,
-                  preparedData["raw-slow-backward"][0].timestamp,
-                  preparedData["raw-fast-forward"][0].timestamp,
-                  preparedData["raw-fast-backward"][0].timestamp};
-}
-
-void AnalysisManager::PrepareAngularDrivetrainData() {
-  using Data = std::array<double, 9>;
-  wpi::StringMap<std::vector<Data>> data;
-  wpi::StringMap<std::vector<PreparedData>> preparedData;
-
-  // Store the relevant raw data columns.
-  static constexpr size_t kTimeCol = 0;
-  static constexpr size_t kLVoltageCol = 1;
-  static constexpr size_t kRVoltageCol = 2;
-  static constexpr size_t kLPosCol = 3;
-  static constexpr size_t kRPosCol = 4;
-  static constexpr size_t kLVelCol = 5;
-  static constexpr size_t kRVelCol = 6;
-  static constexpr size_t kAngleCol = 7;
-  static constexpr size_t kAngularRateCol = 8;
-
-  WPI_INFO(m_logger, "{}", "Reading JSON data.");
-  // Get the major components from the JSON and store them inside a StringMap.
-  for (auto&& key : AnalysisManager::kJsonDataKeys) {
-    data[key] = m_json.at(key).get<std::vector<Data>>();
-  }
-
-  WPI_INFO(m_logger, "{}", "Preprocessing raw data.");
-  // Ensure that voltage and velocity have the same sign. Also multiply
-  // positions and velocities by the factor.
-  for (auto it = data.begin(); it != data.end(); ++it) {
-    for (auto&& pt : it->second) {
-      pt[kLPosCol] *= m_factor;
-      pt[kRPosCol] *= m_factor;
-      pt[kLVelCol] *= m_factor;
-      pt[kRVelCol] *= m_factor;
-
-      // Stores the average voltages in the left voltage column.
-      // This aggregates the left and right voltages into a single voltage
-      // column for the ConvertToPrepared() method. std::copysign() ensures the
-      // polarity of the voltage matches the direction the robot turns.
-      pt[kLVoltageCol] = std::copysign(
-          (std::abs(pt[kLVoltageCol]) + std::abs(pt[kRVoltageCol])) / 2,
-          pt[kAngularRateCol]);
-
-      // ω = (v_r - v_l) / trackwidth
-      // v = ωr => v = ω * trackwidth / 2
-      // (v_r - v_l) / trackwidth * (trackwidth / 2) = (v_r - v_l) / 2
-      // However, since we know this is an angular test, the left and right
-      // wheel velocities will have opposite signs, allowing us to add their
-      // absolute values and get the same result (in terms of magnitude).
-      // std::copysign() is used to make sure the direction of the wheel
-      // velocities matches the direction the robot turns.
-      pt[kAngularRateCol] =
-          std::copysign((std::abs(pt[kRVelCol]) + std::abs(pt[kLVelCol])) / 2,
-                        pt[kAngularRateCol]);
-    }
-  }
-
-  WPI_INFO(m_logger, "{}", "Calculating trackwidth");
-  // Aggregating all the deltas from all the tests
-  double leftDelta = 0.0;
-  double rightDelta = 0.0;
-  double angleDelta = 0.0;
-  for (const auto& it : data) {
-    auto key = it.first();
-    auto& trackWidthData = data[key];
-    leftDelta += std::abs(trackWidthData.back()[kLPosCol] -
-                          trackWidthData.front()[kLPosCol]);
-    rightDelta += std::abs(trackWidthData.back()[kRPosCol] -
-                           trackWidthData.front()[kRPosCol]);
-    angleDelta += std::abs(trackWidthData.back()[kAngleCol] -
-                           trackWidthData.front()[kAngleCol]);
-  }
-  m_trackWidth = sysid::CalculateTrackWidth(leftDelta, rightDelta,
-                                            units::radian_t{angleDelta});
-
-  WPI_INFO(m_logger, "{}", "Copying raw data.");
-  CopyRawData(&data);
-
-  WPI_INFO(m_logger, "{}", "Converting to PreparedData struct.");
-  // Convert raw data to prepared data
-  for (const auto& it : data) {
-    auto key = it.first();
-    preparedData[key] = ConvertToPrepared<9, kTimeCol, kLVoltageCol, kAngleCol,
-                                          kAngularRateCol>(data[key]);
-  }
-
-  // Create the distinct datasets and store them
-  m_originalDataset[static_cast<int>(
-      AnalysisManager::Settings::DrivetrainDataset::kCombined)] =
-      CombineDatasets(preparedData["original-raw-slow-forward"],
-                      preparedData["original-raw-slow-backward"],
-                      preparedData["original-raw-fast-forward"],
-                      preparedData["original-raw-fast-backward"]);
-
-  WPI_INFO(m_logger, "{}", "Applying trimming and filtering.");
-  sysid::InitialTrimAndFilter(&preparedData, &m_settings, m_positionDelays,
-                              m_velocityDelays, m_minStepTime, m_maxStepTime);
-
-  WPI_INFO(m_logger, "{}", "Acceleration filtering.");
-  sysid::AccelFilter(&preparedData);
-
-  WPI_INFO(m_logger, "{}", "Storing datasets.");
-  // Create the distinct datasets and store them
-  m_rawDataset[static_cast<int>(
-      AnalysisManager::Settings::DrivetrainDataset::kCombined)] =
-      CombineDatasets(
-          preparedData["raw-slow-forward"], preparedData["raw-slow-backward"],
-          preparedData["raw-fast-forward"], preparedData["raw-fast-backward"]);
-  m_filteredDataset[static_cast<int>(
-      AnalysisManager::Settings::DrivetrainDataset::kCombined)] =
-      CombineDatasets(
-          preparedData["slow-forward"], preparedData["slow-backward"],
-          preparedData["fast-forward"], preparedData["fast-backward"]);
-
-  m_startTimes = {preparedData["slow-forward"][0].timestamp,
-                  preparedData["slow-backward"][0].timestamp,
-                  preparedData["fast-forward"][0].timestamp,
-                  preparedData["fast-backward"][0].timestamp};
-}
-
-void AnalysisManager::PrepareLinearDrivetrainData() {
-  using Data = std::array<double, 9>;
-  wpi::StringMap<std::vector<Data>> data;
-  wpi::StringMap<std::vector<PreparedData>> preparedData;
-
-  // Store the relevant raw data columns.
-  static constexpr size_t kTimeCol = 0;
-  static constexpr size_t kLVoltageCol = 1;
-  static constexpr size_t kRVoltageCol = 2;
-  static constexpr size_t kLPosCol = 3;
-  static constexpr size_t kRPosCol = 4;
-  static constexpr size_t kLVelCol = 5;
-  static constexpr size_t kRVelCol = 6;
-
-  // Get the major components from the JSON and store them inside a StringMap.
-  WPI_INFO(m_logger, "{}", "Reading JSON data.");
-  for (auto&& key : AnalysisManager::kJsonDataKeys) {
-    data[key] = m_json.at(key).get<std::vector<Data>>();
-  }
-
-  // Ensure that voltage and velocity have the same sign. Also multiply
-  // positions and velocities by the factor.
-  WPI_INFO(m_logger, "{}", "Preprocessing raw data.");
-  for (auto it = data.begin(); it != data.end(); ++it) {
-    for (auto&& pt : it->second) {
-      pt[kLVoltageCol] = std::copysign(pt[kLVoltageCol], pt[kLVelCol]);
-      pt[kRVoltageCol] = std::copysign(pt[kRVoltageCol], pt[kRVelCol]);
-      pt[kLPosCol] *= m_factor;
-      pt[kRPosCol] *= m_factor;
-      pt[kLVelCol] *= m_factor;
-      pt[kRVelCol] *= m_factor;
-    }
-  }
-
-  WPI_INFO(m_logger, "{}", "Copying raw data.");
-  CopyRawData(&data);
-
-  // Convert data to PreparedData
-  WPI_INFO(m_logger, "{}", "Converting to PreparedData struct.");
-  for (auto& it : data) {
-    auto key = it.first();
-
-    preparedData[fmt::format("left-{}", key)] =
-        ConvertToPrepared<9, kTimeCol, kLVoltageCol, kLPosCol, kLVelCol>(
-            data[key]);
-    preparedData[fmt::format("right-{}", key)] =
-        ConvertToPrepared<9, kTimeCol, kRVoltageCol, kRPosCol, kRVelCol>(
-            data[key]);
-  }
-
-  // Create the distinct raw datasets and store them
-  auto originalSlowForward = AnalysisManager::DataConcat(
-      preparedData["left-original-raw-slow-forward"],
-      preparedData["right-original-raw-slow-forward"]);
-  auto originalSlowBackward = AnalysisManager::DataConcat(
-      preparedData["left-original-raw-slow-backward"],
-      preparedData["right-original-raw-slow-backward"]);
-  auto originalFastForward = AnalysisManager::DataConcat(
-      preparedData["left-original-raw-fast-forward"],
-      preparedData["right-original-raw-fast-forward"]);
-  auto originalFastBackward = AnalysisManager::DataConcat(
-      preparedData["left-original-raw-fast-backward"],
-      preparedData["right-original-raw-fast-backward"]);
-  m_originalDataset[static_cast<int>(
-      AnalysisManager::Settings::DrivetrainDataset::kCombined)] =
-      CombineDatasets(originalSlowForward, originalSlowBackward,
-                      originalFastForward, originalFastBackward);
-  m_originalDataset[static_cast<int>(
-      AnalysisManager::Settings::DrivetrainDataset::kLeft)] =
-      CombineDatasets(preparedData["left-original-raw-slow-forward"],
-                      preparedData["left-original-raw-slow-backward"],
-                      preparedData["left-original-raw-fast-forward"],
-                      preparedData["left-original-raw-fast-backward"]);
-  m_originalDataset[static_cast<int>(
-      AnalysisManager::Settings::DrivetrainDataset::kRight)] =
-      CombineDatasets(preparedData["right-original-raw-slow-forward"],
-                      preparedData["right-original-raw-slow-backward"],
-                      preparedData["right-original-raw-fast-forward"],
-                      preparedData["right-original-raw-fast-backward"]);
-
-  WPI_INFO(m_logger, "{}", "Applying trimming and filtering.");
-  sysid::InitialTrimAndFilter(&preparedData, &m_settings, m_positionDelays,
-                              m_velocityDelays, m_minStepTime, m_maxStepTime);
-
-  auto slowForward = AnalysisManager::DataConcat(
-      preparedData["left-slow-forward"], preparedData["right-slow-forward"]);
-  auto slowBackward = AnalysisManager::DataConcat(
-      preparedData["left-slow-backward"], preparedData["right-slow-backward"]);
-  auto fastForward = AnalysisManager::DataConcat(
-      preparedData["left-fast-forward"], preparedData["right-fast-forward"]);
-  auto fastBackward = AnalysisManager::DataConcat(
-      preparedData["left-fast-backward"], preparedData["right-fast-backward"]);
-
-  WPI_INFO(m_logger, "{}", "Acceleration filtering.");
-  sysid::AccelFilter(&preparedData);
-
-  WPI_INFO(m_logger, "{}", "Storing datasets.");
-
-  // Create the distinct raw datasets and store them
-  auto rawSlowForward =
-      AnalysisManager::DataConcat(preparedData["left-raw-slow-forward"],
-                                  preparedData["right-raw-slow-forward"]);
-  auto rawSlowBackward =
-      AnalysisManager::DataConcat(preparedData["left-raw-slow-backward"],
-                                  preparedData["right-raw-slow-backward"]);
-  auto rawFastForward =
-      AnalysisManager::DataConcat(preparedData["left-raw-fast-forward"],
-                                  preparedData["right-raw-fast-forward"]);
-  auto rawFastBackward =
-      AnalysisManager::DataConcat(preparedData["left-raw-fast-backward"],
-                                  preparedData["right-raw-fast-backward"]);
-
-  m_rawDataset[static_cast<int>(
-      AnalysisManager::Settings::DrivetrainDataset::kCombined)] =
-      CombineDatasets(rawSlowForward, rawSlowBackward, rawFastForward,
-                      rawFastBackward);
-  m_rawDataset[static_cast<int>(
-      AnalysisManager::Settings::DrivetrainDataset::kLeft)] =
-      CombineDatasets(preparedData["left-raw-slow-forward"],
-                      preparedData["left-raw-slow-backward"],
-                      preparedData["left-raw-fast-forward"],
-                      preparedData["left-raw-fast-backward"]);
-  m_rawDataset[static_cast<int>(
-      AnalysisManager::Settings::DrivetrainDataset::kRight)] =
-      CombineDatasets(preparedData["right-raw-slow-forward"],
-                      preparedData["right-raw-slow-backward"],
-                      preparedData["right-raw-fast-forward"],
-                      preparedData["right-raw-fast-backward"]);
-
-  // Create the distinct filtered datasets and store them
-  m_filteredDataset[static_cast<int>(
-      AnalysisManager::Settings::DrivetrainDataset::kCombined)] =
-      CombineDatasets(slowForward, slowBackward, fastForward, fastBackward);
-  m_filteredDataset[static_cast<int>(
-      AnalysisManager::Settings::DrivetrainDataset::kLeft)] =
-      CombineDatasets(preparedData["left-slow-forward"],
-                      preparedData["left-slow-backward"],
-                      preparedData["left-fast-forward"],
-                      preparedData["left-fast-backward"]);
-  m_filteredDataset[static_cast<int>(
-      AnalysisManager::Settings::DrivetrainDataset::kRight)] =
-      CombineDatasets(preparedData["right-slow-forward"],
-                      preparedData["right-slow-backward"],
-                      preparedData["right-fast-forward"],
-                      preparedData["right-fast-backward"]);
-
-  m_startTimes = {
-      rawSlowForward.front().timestamp, rawSlowBackward.front().timestamp,
-      rawFastForward.front().timestamp, rawFastBackward.front().timestamp};
+  m_startTimes = {preparedData["raw-quasistatic-forward"][0].timestamp,
+                  preparedData["raw-quasistatic-reverse"][0].timestamp,
+                  preparedData["raw-dynamic-forward"][0].timestamp,
+                  preparedData["raw-dynamic-reverse"][0].timestamp};
 }
 
 AnalysisManager::AnalysisManager(Settings& settings, wpi::Logger& logger)
-    : m_logger{logger},
-      m_settings{settings},
-      m_type{analysis::kSimple},
-      m_unit{"Meters"},
-      m_factor{1} {}
+    : m_logger{logger}, m_settings{settings} {}
 
-AnalysisManager::AnalysisManager(std::string_view path, Settings& settings,
+AnalysisManager::AnalysisManager(TestData data, Settings& settings,
                                  wpi::Logger& logger)
-    : m_logger{logger}, m_settings{settings} {
-  {
-    // Read JSON from the specified path
-    std::error_code ec;
-    std::unique_ptr<wpi::MemoryBuffer> fileBuffer =
-        wpi::MemoryBuffer::GetFile(path, ec);
-    if (fileBuffer == nullptr || ec) {
-      throw FileReadingError(path);
-    }
-
-    m_json = wpi::json::parse(fileBuffer->begin(), fileBuffer->end());
-
-    WPI_INFO(m_logger, "Read {}", path);
-  }
-
-  // Check that we have a sysid JSON
-  if (m_json.find("sysid") == m_json.end()) {
-    // If it's not a sysid JSON, try converting it from frc-char format
-    std::string newPath = sysid::ConvertJSON(path, logger);
-
-    // Read JSON from the specified path
-    std::error_code ec;
-    std::unique_ptr<wpi::MemoryBuffer> fileBuffer =
-        wpi::MemoryBuffer::GetFile(path, ec);
-    if (fileBuffer == nullptr || ec) {
-      throw FileReadingError(newPath);
-    }
-
-    m_json = wpi::json::parse(fileBuffer->begin(), fileBuffer->end());
-
-    WPI_INFO(m_logger, "Read {}", newPath);
-  }
-
-  WPI_INFO(m_logger, "Parsing initial data of {}", path);
-  // Get the analysis type from the JSON.
-  m_type = sysid::analysis::FromName(m_json.at("test").get<std::string>());
-
-  // Get the rotation -> output units factor from the JSON.
-  m_unit = m_json.at("units").get<std::string>();
-  m_factor = m_json.at("unitsPerRotation").get<double>();
-  WPI_DEBUG(m_logger, "Parsing units per rotation as {} {} per rotation",
-            m_factor, m_unit);
-
+    : m_data{std::move(data)}, m_logger{logger}, m_settings{settings} {
   // Reset settings for Dynamic Test Limits
   m_settings.stepTestDuration = units::second_t{0.0};
   m_settings.motionThreshold = std::numeric_limits<double>::infinity();
 }
 
 void AnalysisManager::PrepareData() {
-  WPI_INFO(m_logger, "Preparing {} data", m_type.name);
-  if (m_type == analysis::kDrivetrain) {
-    PrepareLinearDrivetrainData();
-  } else if (m_type == analysis::kDrivetrainAngular) {
-    PrepareAngularDrivetrainData();
-  } else {
-    PrepareGeneralData();
-  }
+  //  WPI_INFO(m_logger, "Preparing {} data", m_data.mechanismType.name);
+
+  PrepareGeneralData();
+
   WPI_INFO(m_logger, "{}", "Finished Preparing Data");
 }
 
@@ -515,12 +192,13 @@
 
   WPI_INFO(m_logger, "{}", "Calculating Gains");
   // Calculate feedforward gains from the data.
-  const auto& ff = sysid::CalculateFeedforwardGains(GetFilteredData(), m_type);
-  FeedforwardGains ffGains = {ff, m_trackWidth};
+  const auto& ff = sysid::CalculateFeedforwardGains(
+      GetFilteredData(), m_data.mechanismType, false);
+  FeedforwardGains ffGains = {ff};
 
-  const auto& Ks = std::get<0>(ff)[0];
-  const auto& Kv = std::get<0>(ff)[1];
-  const auto& Ka = std::get<0>(ff)[2];
+  const auto& Ks = ff.coeffs[0];
+  const auto& Kv = ff.coeffs[1];
+  const auto& Ka = ff.coeffs[2];
 
   if (Ka <= 0 || Kv < 0) {
     throw InvalidDataError(
@@ -542,27 +220,20 @@
   if (m_settings.type == FeedbackControllerLoopType::kPosition) {
     fb = sysid::CalculatePositionFeedbackGains(
         m_settings.preset, m_settings.lqr, Kv, Ka,
-        m_settings.convertGainsToEncTicks
-            ? m_settings.gearing * m_settings.cpr * m_factor
-            : 1);
+        m_settings.convertGainsToEncTicks ? m_settings.gearing * m_settings.cpr
+                                          : 1);
   } else {
     fb = sysid::CalculateVelocityFeedbackGains(
         m_settings.preset, m_settings.lqr, Kv, Ka,
-        m_settings.convertGainsToEncTicks
-            ? m_settings.gearing * m_settings.cpr * m_factor
-            : 1);
+        m_settings.convertGainsToEncTicks ? m_settings.gearing * m_settings.cpr
+                                          : 1);
   }
 
   return fb;
 }
 
-void AnalysisManager::OverrideUnits(std::string_view unit,
-                                    double unitsPerRotation) {
-  m_unit = unit;
-  m_factor = unitsPerRotation;
+void AnalysisManager::OverrideUnits(std::string_view unit) {
+  m_data.distanceUnit = unit;
 }
 
-void AnalysisManager::ResetUnitsFromJSON() {
-  m_unit = m_json.at("units").get<std::string>();
-  m_factor = m_json.at("unitsPerRotation").get<double>();
-}
+void AnalysisManager::ResetUnitsFromJSON() {}
diff --git a/sysid/src/main/native/cpp/analysis/AnalysisType.cpp b/sysid/src/main/native/cpp/analysis/AnalysisType.cpp
index 18b461f..6ef27c9 100644
--- a/sysid/src/main/native/cpp/analysis/AnalysisType.cpp
+++ b/sysid/src/main/native/cpp/analysis/AnalysisType.cpp
@@ -7,12 +7,6 @@
 using namespace sysid;
 
 AnalysisType sysid::analysis::FromName(std::string_view name) {
-  if (name == "Drivetrain") {
-    return sysid::analysis::kDrivetrain;
-  }
-  if (name == "Drivetrain (Angular)") {
-    return sysid::analysis::kDrivetrainAngular;
-  }
   if (name == "Elevator") {
     return sysid::analysis::kElevator;
   }
diff --git a/sysid/src/main/native/cpp/analysis/FeedforwardAnalysis.cpp b/sysid/src/main/native/cpp/analysis/FeedforwardAnalysis.cpp
index b7a9fce..110ff94 100644
--- a/sysid/src/main/native/cpp/analysis/FeedforwardAnalysis.cpp
+++ b/sysid/src/main/native/cpp/analysis/FeedforwardAnalysis.cpp
@@ -4,8 +4,13 @@
 
 #include "sysid/analysis/FeedforwardAnalysis.h"
 
+#include <array>
+#include <bitset>
 #include <cmath>
 
+#include <Eigen/Eigenvalues>
+#include <fmt/format.h>
+#include <fmt/ranges.h>
 #include <units/math.h>
 #include <units/time.h>
 
@@ -13,10 +18,25 @@
 #include "sysid/analysis/FilteringUtils.h"
 #include "sysid/analysis/OLS.h"
 
-using namespace sysid;
+namespace sysid {
 
 /**
- * Populates OLS data for (xₖ₊₁ − xₖ)/τ = αxₖ + βuₖ + γ sgn(xₖ).
+ * Populates OLS data for the following models:
+ *
+ * Simple, Drivetrain, DrivetrainAngular:
+ *
+ *   (xₖ₊₁ − xₖ)/τ = αxₖ + βuₖ + γ sgn(xₖ)
+ *
+ * Elevator:
+ *
+ *   (xₖ₊₁ − xₖ)/τ = αxₖ + βuₖ + γ sgn(xₖ) + δ
+ *
+ * Arm:
+ *
+ *   (xₖ₊₁ − xₖ)/τ = αxₖ + βuₖ + γ sgn(xₖ) + δ cos(angle) + ε sin(angle)
+ *
+ * OLS performs best with the noisiest variable as the dependent variable, so we
+ * regress acceleration in terms of the other variables.
  *
  * @param d List of characterization data.
  * @param type Type of system being identified.
@@ -27,36 +47,136 @@
                             const AnalysisType& type,
                             Eigen::Block<Eigen::MatrixXd> X,
                             Eigen::VectorBlock<Eigen::VectorXd> y) {
+  // Fill in X and y row-wise
   for (size_t sample = 0; sample < d.size(); ++sample) {
     const auto& pt = d[sample];
 
-    // Add the velocity term (for α)
+    // Set the velocity term (for α)
     X(sample, 0) = pt.velocity;
 
-    // Add the voltage term (for β)
+    // Set the voltage term (for β)
     X(sample, 1) = pt.voltage;
 
-    // Add the intercept term (for γ)
+    // Set the intercept term (for γ)
     X(sample, 2) = std::copysign(1, pt.velocity);
 
-    // Add test-specific variables
+    // Set test-specific variables
     if (type == analysis::kElevator) {
-      // Add the gravity term (for Kg)
+      // Set the gravity term (for δ)
       X(sample, 3) = 1.0;
     } else if (type == analysis::kArm) {
-      // Add the cosine and sine terms (for Kg)
+      // Set the cosine and sine terms (for δ and ε)
       X(sample, 3) = pt.cos;
       X(sample, 4) = pt.sin;
     }
 
-    // Add the dependent variable (acceleration)
+    // Set the dependent variable (acceleration)
     y(sample) = pt.acceleration;
   }
 }
 
-std::tuple<std::vector<double>, double, double>
-sysid::CalculateFeedforwardGains(const Storage& data,
-                                 const AnalysisType& type) {
+/**
+ * Throws an InsufficientSamplesError if the collected data is poor for OLS.
+ *
+ * @param X The collected data in matrix form for OLS.
+ * @param type The analysis type.
+ */
+static void CheckOLSDataQuality(const Eigen::MatrixXd& X,
+                                const AnalysisType& type) {
+  Eigen::SelfAdjointEigenSolver<Eigen::MatrixXd> eigSolver{X.transpose() * X};
+  const Eigen::VectorXd& eigvals = eigSolver.eigenvalues();
+  const Eigen::MatrixXd& eigvecs = eigSolver.eigenvectors();
+
+  // Bits are Ks, Kv, Ka, Kg, offset
+  std::bitset<5> badGains;
+
+  constexpr double threshold = 10.0;
+
+  // For n x n matrix XᵀX, need n nonzero eigenvalues for good fit
+  for (int row = 0; row < eigvals.rows(); ++row) {
+    // Find row of eigenvector with largest magnitude. This determines the
+    // primary regression variable that corresponds to the eigenvalue.
+    int maxIndex;
+    double maxCoeff = eigvecs.col(row).cwiseAbs().maxCoeff(&maxIndex);
+
+    // Check whether the eigenvector component along the regression variable's
+    // direction is below the threshold. If it is, the regression variable's fit
+    // is bad.
+    if (std::abs(eigvals(row) * maxCoeff) <= threshold) {
+      // Fit for α is bad
+      if (maxIndex == 0) {
+        // Affects Kv
+        badGains.set(1);
+      }
+
+      // Fit for β is bad
+      if (maxIndex == 1) {
+        // Affects all gains
+        badGains.set();
+        break;
+      }
+
+      // Fit for γ is bad
+      if (maxIndex == 2) {
+        // Affects Ks
+        badGains.set(0);
+      }
+
+      // Fit for δ is bad
+      if (maxIndex == 3) {
+        if (type == analysis::kElevator) {
+          // Affects Kg
+          badGains.set(3);
+        } else if (type == analysis::kArm) {
+          // Affects Kg and offset
+          badGains.set(3);
+          badGains.set(4);
+        }
+      }
+
+      // Fit for ε is bad
+      if (maxIndex == 4) {
+        // Affects Kg and offset
+        badGains.set(3);
+        badGains.set(4);
+      }
+    }
+  }
+
+  // If any gains are bad, throw an error
+  if (badGains.any()) {
+    // Create list of bad gain names
+    constexpr std::array gainNames{"Ks", "Kv", "Ka", "Kg", "offset"};
+    std::vector<std::string_view> badGainsList;
+    for (size_t i = 0; i < badGains.size(); ++i) {
+      if (badGains.test(i)) {
+        badGainsList.emplace_back(gainNames[i]);
+      }
+    }
+
+    std::string error = fmt::format("Insufficient samples to compute {}.\n\n",
+                                    fmt::join(badGainsList, ", "));
+
+    // If all gains are bad, the robot may not have moved
+    if (badGains.all()) {
+      error += "Either no data was collected or the robot didn't move.\n\n";
+    }
+
+    // Append guidance for fixing the data
+    error +=
+        "Ensure the data has:\n\n"
+        "  * at least 2 steady-state velocity events to separate Ks from Kv\n"
+        "  * at least 1 acceleration event to find Ka\n"
+        "  * for elevators, enough vertical motion to measure gravity\n"
+        "  * for arms, enough range of motion to measure gravity and encoder "
+        "offset\n";
+    throw InsufficientSamplesError{error};
+  }
+}
+
+OLSResult CalculateFeedforwardGains(const Storage& data,
+                                    const AnalysisType& type,
+                                    bool throwOnBadData) {
   // Iterate through the data and add it to our raw vector.
   const auto& [slowForward, slowBackward, fastForward, fastBackward] = data;
 
@@ -87,34 +207,68 @@
                   X.block(rowOffset, 0, fastBackward.size(), X.cols()),
                   y.segment(rowOffset, fastBackward.size()));
 
-  // Perform OLS with accel = alpha*vel + beta*voltage + gamma*signum(vel)
-  // OLS performs best with the noisiest variable as the dependent var,
-  // so we regress accel in terms of the other variables.
-  auto ols = sysid::OLS(X, y);
-  double alpha = std::get<0>(ols)[0];  // -Kv/Ka
-  double beta = std::get<0>(ols)[1];   // 1/Ka
-  double gamma = std::get<0>(ols)[2];  // -Ks/Ka
-
-  // Initialize gains list with Ks, Kv, and Ka
-  std::vector<double> gains{-gamma / beta, -alpha / beta, 1 / beta};
-
-  if (type == analysis::kElevator) {
-    // Add Kg to gains list
-    double delta = std::get<0>(ols)[3];  // -Kg/Ka
-    gains.emplace_back(-delta / beta);
+  // Check quality of collected data
+  if (throwOnBadData) {
+    CheckOLSDataQuality(X, type);
   }
 
-  if (type == analysis::kArm) {
-    double delta = std::get<0>(ols)[3];    // -Kg/Ka cos(offset)
-    double epsilon = std::get<0>(ols)[4];  // Kg/Ka sin(offset)
+  std::vector<double> gains;
+  gains.reserve(X.rows());
 
-    // Add Kg to gains list
-    gains.emplace_back(std::hypot(delta, epsilon) / beta);
+  auto ols = OLS(X, y);
 
-    // Add offset to gains list
-    gains.emplace_back(std::atan2(epsilon, -delta));
+  // Calculate feedforward gains
+  //
+  // See docs/ols-derivations.md for more details.
+  {
+    // dx/dt = -Kv/Ka x + 1/Ka u - Ks/Ka sgn(x)
+    // dx/dt = αx + βu + γ sgn(x)
+
+    // α = -Kv/Ka
+    // β = 1/Ka
+    // γ = -Ks/Ka
+    double α = ols.coeffs[0];
+    double β = ols.coeffs[1];
+    double γ = ols.coeffs[2];
+
+    // Ks = -γ/β
+    // Kv = -α/β
+    // Ka = 1/β
+    gains.emplace_back(-γ / β);
+    gains.emplace_back(-α / β);
+    gains.emplace_back(1 / β);
+
+    if (type == analysis::kElevator) {
+      // dx/dt = -Kv/Ka x + 1/Ka u - Ks/Ka sgn(x) - Kg/Ka
+      // dx/dt = αx + βu + γ sgn(x) + δ
+
+      // δ = -Kg/Ka
+      double δ = ols.coeffs[3];
+
+      // Kg = -δ/β
+      gains.emplace_back(-δ / β);
+    }
+
+    if (type == analysis::kArm) {
+      // dx/dt = -Kv/Ka x + 1/Ka u - Ks/Ka sgn(x)
+      //           - Kg/Ka cos(offset) cos(angle)                   NOLINT
+      //           + Kg/Ka sin(offset) sin(angle)                   NOLINT
+      // dx/dt = αx + βu + γ sgn(x) + δ cos(angle) + ε sin(angle)   NOLINT
+
+      // δ = -Kg/Ka cos(offset)
+      // ε = Kg/Ka sin(offset)
+      double δ = ols.coeffs[3];
+      double ε = ols.coeffs[4];
+
+      // Kg = hypot(δ, ε)/β      NOLINT
+      // offset = atan2(ε, -δ)   NOLINT
+      gains.emplace_back(std::hypot(δ, ε) / β);
+      gains.emplace_back(std::atan2(ε, -δ));
+    }
   }
 
   // Gains are Ks, Kv, Ka, Kg (elevator/arm only), offset (arm only)
-  return std::tuple{gains, std::get<1>(ols), std::get<2>(ols)};
+  return OLSResult{gains, ols.rSquared, ols.rmse};
 }
+
+}  // namespace sysid
diff --git a/sysid/src/main/native/cpp/analysis/FilteringUtils.cpp b/sysid/src/main/native/cpp/analysis/FilteringUtils.cpp
index 6c66ef8..838968f 100644
--- a/sysid/src/main/native/cpp/analysis/FilteringUtils.cpp
+++ b/sysid/src/main/native/cpp/analysis/FilteringUtils.cpp
@@ -153,32 +153,24 @@
 
   minStepTime = std::min(data->at(0).timestamp - firstTimestamp, minStepTime);
 
-  // If step duration hasn't been set yet, calculate a default (find the entry
-  // before the acceleration first hits zero)
-  if (settings->stepTestDuration <= minStepTime) {
-    // Get noise floor
-    const double accelNoiseFloor = GetNoiseFloor(
-        *data, kNoiseMeanWindow, [](auto&& pt) { return pt.acceleration; });
-    // Find latest element with nonzero acceleration
-    auto endIt = std::find_if(
-        data->rbegin(), data->rend(), [&](const PreparedData& entry) {
-          return std::abs(entry.acceleration) > accelNoiseFloor;
-        });
+  // Find maximum speed reached
+  const auto maxSpeed =
+      GetMaxSpeed(*data, [](auto&& pt) { return pt.velocity; });
+  // Find place where 90% of maximum speed exceeded
+  auto endIt =
+      std::find_if(data->begin(), data->end(), [&](const PreparedData& entry) {
+        return std::abs(entry.velocity) > maxSpeed * 0.9;
+      });
 
-    if (endIt != data->rend()) {
-      // Calculate default duration
-      settings->stepTestDuration = std::min(
-          endIt->timestamp - data->front().timestamp + minStepTime + 1_s,
-          maxStepTime);
-    } else {
-      settings->stepTestDuration = maxStepTime;
-    }
+  if (endIt != data->end()) {
+    settings->stepTestDuration = std::min(
+        endIt->timestamp - data->front().timestamp + minStepTime, maxStepTime);
   }
 
   // Find first entry greater than the step test duration
   auto maxIt =
       std::find_if(data->begin(), data->end(), [&](PreparedData entry) {
-        return entry.timestamp - data->front().timestamp + minStepTime >
+        return entry.timestamp - data->front().timestamp >
                settings->stepTestDuration;
       });
 
@@ -186,6 +178,7 @@
   if (maxIt != data->end()) {
     data->erase(maxIt, data->end());
   }
+
   return std::make_tuple(minStepTime, positionDelay, velocityDelay);
 }
 
@@ -204,6 +197,16 @@
   return std::sqrt(sum / (data.size() - step));
 }
 
+double sysid::GetMaxSpeed(
+    const std::vector<PreparedData>& data,
+    std::function<double(const PreparedData&)> accessorFunction) {
+  double max = 0.0;
+  for (size_t i = 0; i < data.size(); i++) {
+    max = std::max(max, std::abs(accessorFunction(data[i])));
+  }
+  return max;
+}
+
 units::second_t sysid::GetMeanTimeDelta(const std::vector<PreparedData>& data) {
   std::vector<units::second_t> dts;
 
@@ -301,7 +304,7 @@
     auto key = it.first();
     auto& dataset = it.getValue();
 
-    if (IsRaw(key) && wpi::contains(key, "fast")) {
+    if (IsRaw(key) && wpi::contains(key, "dynamic")) {
       auto duration = dataset.back().timestamp - dataset.front().timestamp;
       if (duration > maxStepTime) {
         maxStepTime = duration;
@@ -327,7 +330,7 @@
     for (auto& it : preparedData) {
       auto key = it.first();
       auto& dataset = it.getValue();
-      if (wpi::contains(key, "slow")) {
+      if (wpi::contains(key, "quasistatic")) {
         settings->motionThreshold =
             std::min(settings->motionThreshold,
                      GetNoiseFloor(dataset, kNoiseMeanWindow,
@@ -342,7 +345,7 @@
 
     // Trim quasistatic test data to remove all points where voltage is zero or
     // velocity < motion threshold.
-    if (wpi::contains(key, "slow")) {
+    if (wpi::contains(key, "quasistatic")) {
       dataset.erase(std::remove_if(dataset.begin(), dataset.end(),
                                    [&](const auto& pt) {
                                      return std::abs(pt.voltage) <= 0 ||
@@ -366,7 +369,7 @@
     PrepareMechData(&dataset, unit);
 
     // Trims filtered Dynamic Test Data
-    if (IsFiltered(key) && wpi::contains(key, "fast")) {
+    if (IsFiltered(key) && wpi::contains(key, "dynamic")) {
       // Get the filtered dataset name
       auto filteredKey = RemoveStr(key, "raw-");
 
diff --git a/sysid/src/main/native/cpp/analysis/JSONConverter.cpp b/sysid/src/main/native/cpp/analysis/JSONConverter.cpp
deleted file mode 100644
index 9bab8c6..0000000
--- a/sysid/src/main/native/cpp/analysis/JSONConverter.cpp
+++ /dev/null
@@ -1,164 +0,0 @@
-// Copyright (c) FIRST and other WPILib contributors.
-// Open Source Software; you can modify and/or share it under the terms of
-// the WPILib BSD license file in the root directory of this project.
-
-#include "sysid/analysis/JSONConverter.h"
-
-#include <stdexcept>
-#include <string>
-
-#include <fmt/core.h>
-#include <fmt/format.h>
-#include <wpi/Logger.h>
-#include <wpi/MemoryBuffer.h>
-#include <wpi/fmt/raw_ostream.h>
-#include <wpi/json.h>
-#include <wpi/raw_ostream.h>
-
-#include "sysid/Util.h"
-#include "sysid/analysis/AnalysisManager.h"
-#include "sysid/analysis/AnalysisType.h"
-
-// Sizes of the arrays for new sysid data.
-static constexpr size_t kDrivetrainSize = 9;
-static constexpr size_t kGeneralSize = 4;
-
-// Indices for the old data.
-static constexpr size_t kTimestampCol = 0;
-static constexpr size_t kLVoltsCol = 3;
-static constexpr size_t kRVoltsCol = 4;
-static constexpr size_t kLPosCol = 5;
-static constexpr size_t kRPosCol = 6;
-static constexpr size_t kLVelCol = 7;
-static constexpr size_t kRVelCol = 8;
-
-static wpi::json GetJSON(std::string_view path, wpi::Logger& logger) {
-  std::error_code ec;
-  std::unique_ptr<wpi::MemoryBuffer> fileBuffer =
-      wpi::MemoryBuffer::GetFile(path, ec);
-  if (fileBuffer == nullptr || ec) {
-    throw std::runtime_error(fmt::format("Unable to read: {}", path));
-  }
-
-  wpi::json json = wpi::json::parse(fileBuffer->begin(), fileBuffer->end());
-  WPI_INFO(logger, "Read frc-characterization JSON from {}", path);
-  return json;
-}
-
-std::string sysid::ConvertJSON(std::string_view path, wpi::Logger& logger) {
-  wpi::json ojson = GetJSON(path, logger);
-
-  auto type = sysid::analysis::FromName(ojson.at("test").get<std::string>());
-  auto factor = ojson.at("unitsPerRotation").get<double>();
-  auto unit = ojson.at("units").get<std::string>();
-
-  wpi::json json;
-  for (auto&& key : AnalysisManager::kJsonDataKeys) {
-    if (type == analysis::kDrivetrain) {
-      // Get the old data; create a vector for the new data; reserve the
-      // appropriate size for the new data.
-      auto odata = ojson.at(key).get<std::vector<std::array<double, 10>>>();
-      std::vector<std::array<double, kDrivetrainSize>> data;
-      data.reserve(odata.size());
-
-      // Transfer the data.
-      for (auto&& pt : odata) {
-        data.push_back(std::array<double, kDrivetrainSize>{
-            pt[kTimestampCol], pt[kLVoltsCol], pt[kRVoltsCol], pt[kLPosCol],
-            pt[kRPosCol], pt[kLVelCol], pt[kRVelCol], 0.0, 0.0});
-      }
-      json[key] = data;
-    } else {
-      // Get the old data; create a vector for the new data; reserve the
-      // appropriate size for the new data.
-      auto odata = ojson.at(key).get<std::vector<std::array<double, 10>>>();
-      std::vector<std::array<double, kGeneralSize>> data;
-      data.reserve(odata.size());
-
-      // Transfer the data.
-      for (auto&& pt : odata) {
-        data.push_back(std::array<double, kGeneralSize>{
-            pt[kTimestampCol], pt[kLVoltsCol], pt[kLPosCol], pt[kLVelCol]});
-      }
-      json[key] = data;
-    }
-  }
-  json["units"] = unit;
-  json["unitsPerRotation"] = factor;
-  json["test"] = type.name;
-  json["sysid"] = true;
-
-  // Write the new file with "_new" appended to it.
-  path.remove_suffix(std::string_view{".json"}.size());
-  std::string loc = fmt::format("{}_new.json", path);
-
-  sysid::SaveFile(json.dump(2), std::filesystem::path{loc});
-
-  WPI_INFO(logger, "Wrote new JSON to: {}", loc);
-  return loc;
-}
-
-std::string sysid::ToCSV(std::string_view path, wpi::Logger& logger) {
-  wpi::json json = GetJSON(path, logger);
-
-  auto type = sysid::analysis::FromName(json.at("test").get<std::string>());
-  auto factor = json.at("unitsPerRotation").get<double>();
-  auto unit = json.at("units").get<std::string>();
-  std::string_view abbreviation = GetAbbreviation(unit);
-
-  std::error_code ec;
-  // Naming: {sysid-json-name}(Test, Units).csv
-  path.remove_suffix(std::string_view{".json"}.size());
-  std::string loc = fmt::format("{} ({}, {}).csv", path, type.name, unit);
-  wpi::raw_fd_ostream outputFile{loc, ec};
-
-  if (ec) {
-    throw std::runtime_error("Unable to write to: " + loc);
-  }
-
-  fmt::print(outputFile, "Timestamp (s),Test,");
-  if (type == analysis::kDrivetrain || type == analysis::kDrivetrainAngular) {
-    fmt::print(
-        outputFile,
-        "Left Volts (V),Right Volts (V),Left Position ({0}),Right "
-        "Position ({0}),Left Velocity ({0}/s),Right Velocity ({0}/s),Gyro "
-        "Position (deg),Gyro Rate (deg/s)\n",
-        abbreviation);
-  } else {
-    fmt::print(outputFile, "Volts (V),Position({0}),Velocity ({0}/s)\n",
-               abbreviation);
-  }
-  outputFile << "\n";
-
-  for (auto&& key : AnalysisManager::kJsonDataKeys) {
-    if (type == analysis::kDrivetrain || type == analysis::kDrivetrainAngular) {
-      auto tempData =
-          json.at(key).get<std::vector<std::array<double, kDrivetrainSize>>>();
-      for (auto&& pt : tempData) {
-        fmt::print(outputFile, "{},{},{},{},{},{},{},{},{},{}\n",
-                   pt[0],                           // Timestamp
-                   key,                             // Test
-                   pt[1], pt[2],                    // Left and Right Voltages
-                   pt[3] * factor, pt[4] * factor,  // Left and Right Positions
-                   pt[5] * factor, pt[6] * factor,  // Left and Right Velocity
-                   pt[7], pt[8]  // Gyro Position and Velocity
-        );
-      }
-    } else {
-      auto tempData =
-          json.at(key).get<std::vector<std::array<double, kGeneralSize>>>();
-      for (auto&& pt : tempData) {
-        fmt::print(outputFile, "{},{},{},{},{}\n",
-                   pt[0],           // Timestamp,
-                   key,             // Test
-                   pt[1],           // Voltage
-                   pt[2] * factor,  // Position
-                   pt[3] * factor   // Velocity
-        );
-      }
-    }
-  }
-  outputFile.flush();
-  WPI_INFO(logger, "Wrote CSV to: {}", loc);
-  return loc;
-}
diff --git a/sysid/src/main/native/cpp/analysis/OLS.cpp b/sysid/src/main/native/cpp/analysis/OLS.cpp
index d095a48..5d630d0 100644
--- a/sysid/src/main/native/cpp/analysis/OLS.cpp
+++ b/sysid/src/main/native/cpp/analysis/OLS.cpp
@@ -4,45 +4,85 @@
 
 #include "sysid/analysis/OLS.h"
 
-#include <tuple>
-#include <vector>
+#include <cassert>
+#include <cmath>
 
 #include <Eigen/Cholesky>
-#include <Eigen/Core>
 
-using namespace sysid;
+namespace sysid {
 
-std::tuple<std::vector<double>, double, double> sysid::OLS(
-    const Eigen::MatrixXd& X, const Eigen::VectorXd& y) {
+OLSResult OLS(const Eigen::MatrixXd& X, const Eigen::VectorXd& y) {
   assert(X.rows() == y.rows());
 
-  // The linear model can be written as follows:
-  // y = Xβ + u, where y is the dependent observed variable, X is the matrix
-  // of independent variables, β is a vector of coefficients, and u is a
-  // vector of residuals.
+  // The linear regression model can be written as follows:
+  //
+  //   y = Xβ + ε
+  //
+  // where y is the dependent observed variable, X is the matrix of independent
+  // variables, β is a vector of coefficients, and ε is a vector of residuals.
+  //
+  // We want to find the value of β that minimizes εᵀε.
+  //
+  //   ε = y − Xβ
+  //   εᵀε = (y − Xβ)ᵀ(y − Xβ)
+  //
+  //   β̂ = argmin (y − Xβ)ᵀ(y − Xβ)
+  //         β
+  //
+  // Take the partial derivative of the cost function with respect to β and set
+  // it equal to zero, then solve for β̂ .
+  //
+  //   0 = −2Xᵀ(y − Xβ̂)
+  //   0 = Xᵀ(y − Xβ̂)
+  //   0 = Xᵀy − XᵀXβ̂
+  //   XᵀXβ̂ = Xᵀy
+  //   β̂  = (XᵀX)⁻¹Xᵀy
 
-  // We want to minimize u² = uᵀu = (y - Xβ)ᵀ(y - Xβ).
   // β = (XᵀX)⁻¹Xᵀy
+  //
+  // XᵀX is guaranteed to be symmetric positive definite, so an LLT
+  // decomposition can be used.
+  Eigen::MatrixXd β = (X.transpose() * X).llt().solve(X.transpose() * y);
 
-  // Calculate β that minimizes uᵀu.
-  Eigen::MatrixXd beta = (X.transpose() * X).llt().solve(X.transpose() * y);
+  // Error sum of squares
+  double SSE = (y - X * β).squaredNorm();
 
-  // We will now calculate R² or the coefficient of determination, which
-  // tells us how much of the total variation (variation in y) can be
-  // explained by the regression model.
+  // Sample size
+  int n = X.rows();
 
-  // We will first calculate the sum of the squares of the error, or the
-  // variation in error (SSE).
-  double SSE = (y - X * beta).squaredNorm();
+  // Number of explanatory variables
+  int p = β.rows();
 
-  int n = X.cols();
+  // Total sum of squares (total variation in y)
+  //
+  // From slide 24 of
+  // http://www.stat.columbia.edu/~fwood/Teaching/w4315/Fall2009/lecture_11:
+  //
+  //   SSTO = yᵀy - 1/n yᵀJy
+  //
+  // Let J = I.
+  //
+  //   SSTO = yᵀy - 1/n yᵀy
+  //   SSTO = (n − 1)/n yᵀy
+  double SSTO = (n - 1.0) / n * (y.transpose() * y).value();
 
-  // Now we will calculate the total variation in y, known as SSTO.
-  double SSTO = ((y.transpose() * y) - (1.0 / n) * (y.transpose() * y)).value();
+  // R² or the coefficient of determination, which represents how much of the
+  // total variation (variation in y) can be explained by the regression model
+  double rSquared = 1.0 - SSE / SSTO;
 
-  double rSquared = (SSTO - SSE) / SSTO;
-  double adjRSquared = 1.0 - (1.0 - rSquared) * ((n - 1.0) / (n - 3.0));
+  // Adjusted R²
+  //
+  //                       n − 1
+  //   R̅² = 1 − (1 − R²) ---------
+  //                     n − p − 1
+  //
+  // See https://en.wikipedia.org/wiki/Coefficient_of_determination#Adjusted_R2
+  double adjRSquared = 1.0 - (1.0 - rSquared) * ((n - 1.0) / (n - p - 1.0));
+
+  // Root-mean-square error
   double RMSE = std::sqrt(SSE / n);
 
-  return {{beta.data(), beta.data() + beta.rows()}, adjRSquared, RMSE};
+  return {{β.data(), β.data() + β.size()}, adjRSquared, RMSE};
 }
+
+}  // namespace sysid
diff --git a/sysid/src/main/native/cpp/telemetry/TelemetryManager.cpp b/sysid/src/main/native/cpp/telemetry/TelemetryManager.cpp
deleted file mode 100644
index ac97cdb..0000000
--- a/sysid/src/main/native/cpp/telemetry/TelemetryManager.cpp
+++ /dev/null
@@ -1,275 +0,0 @@
-// Copyright (c) FIRST and other WPILib contributors.
-// Open Source Software; you can modify and/or share it under the terms of
-// the WPILib BSD license file in the root directory of this project.
-
-#include "sysid/telemetry/TelemetryManager.h"
-
-#include <algorithm>
-#include <cctype>  // for ::tolower
-#include <numbers>
-#include <stdexcept>
-#include <string>
-#include <utility>
-
-#include <fmt/chrono.h>
-#include <networktables/NetworkTableInstance.h>
-#include <wpi/Logger.h>
-#include <wpi/SmallVector.h>
-#include <wpi/StringExtras.h>
-#include <wpi/raw_ostream.h>
-#include <wpi/timestamp.h>
-
-#include "sysid/Util.h"
-#include "sysid/analysis/AnalysisType.h"
-
-using namespace sysid;
-
-TelemetryManager::TelemetryManager(const Settings& settings,
-                                   wpi::Logger& logger,
-                                   nt::NetworkTableInstance instance)
-    : m_settings(settings), m_logger(logger), m_inst(instance) {}
-
-void TelemetryManager::BeginTest(std::string_view name) {
-  // Create a new test params instance for this test.
-  m_params =
-      TestParameters{name.starts_with("fast"), name.ends_with("forward"),
-                     m_settings.mechanism == analysis::kDrivetrainAngular,
-                     State::WaitingForEnable};
-
-  // Add this test to the list of running tests and set the running flag.
-  m_tests.push_back(std::string{name});
-  m_isRunningTest = true;
-
-  // Set the Voltage Command Entry
-  m_voltageCommand.Set((m_params.fast ? m_settings.stepVoltage
-                                      : m_settings.quasistaticRampRate) *
-                       (m_params.forward ? 1 : -1));
-
-  // Set the test type
-  m_testType.Set(m_params.fast ? "Dynamic" : "Quasistatic");
-
-  // Set the rotate entry
-  m_rotate.Set(m_params.rotate);
-
-  // Set the current mechanism in NT.
-  m_mechanism.Set(m_settings.mechanism.name);
-  // Set Overflow to False
-  m_overflowPub.Set(false);
-  // Set Mechanism Error to False
-  m_mechErrorPub.Set(false);
-  m_inst.Flush();
-
-  // Display the warning message.
-  for (auto&& func : m_callbacks) {
-    func(
-        "Please enable the robot in autonomous mode, and then "
-        "disable it "
-        "before it runs out of space. \n Note: The robot will "
-        "continue "
-        "to move until you disable it - It is your "
-        "responsibility to "
-        "ensure it does not hit anything!");
-  }
-
-  WPI_INFO(m_logger, "Started {} test.", m_tests.back());
-}
-
-void TelemetryManager::EndTest() {
-  // If there is no test running, this is a no-op
-  if (!m_isRunningTest) {
-    return;
-  }
-
-  // Disable the running flag and store the data in the JSON.
-  m_isRunningTest = false;
-  m_data[m_tests.back()] = m_params.data;
-
-  // Call the cancellation callbacks.
-  for (auto&& func : m_callbacks) {
-    std::string msg;
-    if (m_params.mechError) {
-      msg +=
-          "\nERROR: The robot indicated that you are using the wrong project "
-          "for characterizing your mechanism. \nThis most likely means you "
-          "are trying to characterize a mechanism like a Drivetrain with a "
-          "deployed config for a General Mechanism (e.g. Arm, Flywheel, and "
-          "Elevator) or vice versa. Please double check your settings and "
-          "try again.";
-    } else if (!m_params.data.empty()) {
-      std::string units = m_settings.units;
-      std::transform(m_settings.units.begin(), m_settings.units.end(),
-                     units.begin(), ::tolower);
-
-      if (std::string_view{m_settings.mechanism.name}.starts_with(
-              "Drivetrain")) {
-        double p = (m_params.data.back()[3] - m_params.data.front()[3]) *
-                   m_settings.unitsPerRotation;
-        double s = (m_params.data.back()[4] - m_params.data.front()[4]) *
-                   m_settings.unitsPerRotation;
-        double g = m_params.data.back()[7] - m_params.data.front()[7];
-
-        msg = fmt::format(
-            "The left and right encoders traveled {} {} and {} {} "
-            "respectively.\nThe gyro angle delta was {} degrees.",
-            p, units, s, units, g * 180.0 / std::numbers::pi);
-      } else {
-        double p = (m_params.data.back()[2] - m_params.data.front()[2]) *
-                   m_settings.unitsPerRotation;
-        msg = fmt::format("The encoder reported traveling {} {}.", p, units);
-      }
-
-      if (m_params.overflow) {
-        msg +=
-            "\nNOTE: the robot stopped recording data early because the entry "
-            "storage was exceeded.";
-      }
-    } else {
-      msg = "No data was detected.";
-    }
-    func(msg);
-  }
-
-  // Remove previously run test from list of tests if no data was detected.
-  if (m_params.data.empty()) {
-    m_tests.pop_back();
-  }
-
-  // Send a zero command over NT.
-  m_voltageCommand.Set(0.0);
-  m_inst.Flush();
-}
-
-void TelemetryManager::Update() {
-  // If there is no test running, these is nothing to update.
-  if (!m_isRunningTest) {
-    return;
-  }
-
-  // Update the NT entries that we're reading.
-
-  int currAckNumber = m_ackNumberSub.Get();
-  std::string telemetryValue;
-
-  // Get the FMS Control Word.
-  for (auto tsValue : m_fmsControlData.ReadQueue()) {
-    uint32_t ctrl = tsValue.value;
-    m_params.enabled = ctrl & 0x01;
-  }
-
-  // Get the string in the data field.
-  for (auto tsValue : m_telemetry.ReadQueue()) {
-    telemetryValue = tsValue.value;
-  }
-
-  // Get the overflow flag
-  for (auto tsValue : m_overflowSub.ReadQueue()) {
-    m_params.overflow = tsValue.value;
-  }
-
-  // Get the mechanism error flag
-  for (auto tsValue : m_mechErrorSub.ReadQueue()) {
-    m_params.mechError = tsValue.value;
-  }
-
-  // Go through our state machine.
-  if (m_params.state == State::WaitingForEnable) {
-    if (m_params.enabled) {
-      m_params.enableStart = wpi::Now() * 1E-6;
-      m_params.state = State::RunningTest;
-      m_ackNumber = currAckNumber;
-      WPI_INFO(m_logger, "{}", "Transitioned to running test state.");
-    }
-  }
-
-  if (m_params.state == State::RunningTest) {
-    // If for some reason we've disconnected, end the test.
-    if (!m_inst.IsConnected()) {
-      WPI_WARNING(m_logger, "{}",
-                  "NT connection was dropped when executing the test. The test "
-                  "has been canceled.");
-      EndTest();
-    }
-
-    // If the robot has disabled, then we can move on to the next step.
-    if (!m_params.enabled) {
-      m_params.disableStart = wpi::Now() * 1E-6;
-      m_params.state = State::WaitingForData;
-      WPI_INFO(m_logger, "{}", "Transitioned to waiting for data.");
-    }
-  }
-
-  if (m_params.state == State::WaitingForData) {
-    double now = wpi::Now() * 1E-6;
-    m_voltageCommand.Set(0.0);
-    m_inst.Flush();
-
-    // Process valid data
-    if (!telemetryValue.empty() && m_ackNumber < currAckNumber) {
-      m_params.raw = std::move(telemetryValue);
-      m_ackNumber = currAckNumber;
-    }
-
-    // We have the data that we need, so we can parse it and end the test.
-    if (!m_params.raw.empty() &&
-        wpi::starts_with(m_params.raw, m_tests.back())) {
-      // Remove test type from start of string
-      m_params.raw.erase(0, m_params.raw.find(';') + 1);
-
-      // Clean up the string -- remove spaces if there are any.
-      m_params.raw.erase(
-          std::remove_if(m_params.raw.begin(), m_params.raw.end(), ::isspace),
-          m_params.raw.end());
-
-      // Split the string into individual components.
-      wpi::SmallVector<std::string_view, 16> res;
-      wpi::split(m_params.raw, res, ',');
-
-      // Convert each string to double.
-      std::vector<double> values;
-      values.reserve(res.size());
-      for (auto&& str : res) {
-        values.push_back(wpi::parse_float<double>(str).value());
-      }
-
-      // Add the values to our result vector.
-      for (size_t i = 0; i < values.size() - m_settings.mechanism.rawDataSize;
-           i += m_settings.mechanism.rawDataSize) {
-        std::vector<double> d(m_settings.mechanism.rawDataSize);
-
-        std::copy_n(std::make_move_iterator(values.begin() + i),
-                    m_settings.mechanism.rawDataSize, d.begin());
-        m_params.data.push_back(std::move(d));
-      }
-
-      WPI_INFO(m_logger,
-               "Received data with size: {} for the {} test in {} seconds.",
-               m_params.data.size(), m_tests.back(),
-               m_params.data.back()[0] - m_params.data.front()[0]);
-      m_ackNumberPub.Set(++m_ackNumber);
-      EndTest();
-    }
-
-    // If we timed out, end the test and let the user know.
-    if (now - m_params.disableStart > 5.0) {
-      WPI_WARNING(m_logger, "{}",
-                  "TelemetryManager did not receieve data 5 seconds after "
-                  "completing the test...");
-      EndTest();
-    }
-  }
-}
-
-std::string TelemetryManager::SaveJSON(std::string_view location) {
-  m_data["test"] = m_settings.mechanism.name;
-  m_data["units"] = m_settings.units;
-  m_data["unitsPerRotation"] = m_settings.unitsPerRotation;
-  m_data["sysid"] = true;
-
-  std::string loc = fmt::format("{}/sysid_data{:%Y%m%d-%H%M%S}.json", location,
-                                std::chrono::system_clock::now());
-
-  sysid::SaveFile(m_data.dump(2), std::filesystem::path{loc});
-  WPI_INFO(m_logger, "Wrote JSON to: {}", loc);
-
-  return loc;
-}
diff --git a/sysid/src/main/native/cpp/view/Analyzer.cpp b/sysid/src/main/native/cpp/view/Analyzer.cpp
index 3270918..f121ab5 100644
--- a/sysid/src/main/native/cpp/view/Analyzer.cpp
+++ b/sysid/src/main/native/cpp/view/Analyzer.cpp
@@ -28,7 +28,7 @@
 using namespace sysid;
 
 Analyzer::Analyzer(glass::Storage& storage, wpi::Logger& logger)
-    : m_location(""), m_logger(logger) {
+    : m_logger(logger) {
   // Fill the StringMap with preset values.
   m_presets["Default"] = presets::kDefault;
   m_presets["WPILib (2020-)"] = presets::kWPILibNew;
@@ -48,16 +48,14 @@
 void Analyzer::UpdateFeedforwardGains() {
   WPI_INFO(m_logger, "{}", "Gain calc");
   try {
-    const auto& [ff, trackWidth] = m_manager->CalculateFeedforward();
-    m_ff = std::get<0>(ff);
-    m_accelRSquared = std::get<1>(ff);
-    m_accelRMSE = std::get<2>(ff);
-    m_trackWidth = trackWidth;
+    const auto& [ff] = m_manager->CalculateFeedforward();
+    m_ff = ff.coeffs;
+    m_accelRSquared = ff.rSquared;
+    m_accelRMSE = ff.rmse;
     m_settings.preset.measurementDelay =
         m_settings.type == FeedbackControllerLoopType::kPosition
             ? m_manager->GetPositionDelay()
             : m_manager->GetVelocityDelay();
-    m_conversionFactor = m_manager->GetFactor();
     PrepareGraphs();
   } catch (const sysid::InvalidDataError& e) {
     m_state = AnalyzerState::kGeneralDataError;
@@ -81,6 +79,7 @@
 }
 
 void Analyzer::UpdateFeedbackGains() {
+  WPI_INFO(m_logger, "{}", "Updating feedback gains");
   if (m_ff[1] > 0 && m_ff[2] > 0) {
     const auto& fb = m_manager->CalculateFeedback(m_ff);
     m_timescale = units::second_t{m_ff[2] / m_ff[1]};
@@ -119,27 +118,9 @@
          m_state == AnalyzerState::kGeneralDataError;
 }
 
-void Analyzer::DisplayFileSelector() {
-  // Get the current width of the window. This will be used to scale
-  // our UI elements.
-  float width = ImGui::GetContentRegionAvail().x;
-
-  // Show the file location along with an option to choose.
-  if (ImGui::Button("Select")) {
-    m_selector = std::make_unique<pfd::open_file>(
-        "Select Data", "",
-        std::vector<std::string>{"JSON File", SYSID_PFD_JSON_EXT});
-  }
-  ImGui::SameLine();
-  ImGui::SetNextItemWidth(width - ImGui::CalcTextSize("Select").x -
-                          ImGui::GetFontSize() * 5);
-  ImGui::InputText("##location", &m_location, ImGuiInputTextFlags_ReadOnly);
-}
-
 void Analyzer::ResetData() {
   m_plot.ResetData();
   m_manager = std::make_unique<AnalysisManager>(m_settings, m_logger);
-  m_location = "";
   m_ff = std::vector<double>{1, 1, 1};
   UpdateFeedbackGains();
 }
@@ -152,38 +133,15 @@
   ImGui::SameLine(width - ImGui::CalcTextSize("Reset").x);
   if (ImGui::Button("Reset")) {
     ResetData();
-    m_state = AnalyzerState::kWaitingForJSON;
+    m_state = AnalyzerState::kWaitingForData;
     return true;
   }
 
-  if (type == analysis::kDrivetrain) {
-    ImGui::SetNextItemWidth(ImGui::GetFontSize() * kTextBoxWidthMultiple);
-    if (ImGui::Combo("Dataset", &m_dataset, kDatasets, 3)) {
-      m_settings.dataset =
-          static_cast<AnalysisManager::Settings::DrivetrainDataset>(m_dataset);
-      PrepareData();
-    }
-    ImGui::SameLine();
-  } else {
-    m_settings.dataset =
-        AnalysisManager::Settings::DrivetrainDataset::kCombined;
-  }
-
   ImGui::Spacing();
   ImGui::Text(
       "Units:              %s\n"
-      "Units Per Rotation: %.4f\n"
       "Type:               %s",
-      std::string(unit).c_str(), m_conversionFactor, type.name);
-
-  if (type == analysis::kDrivetrainAngular) {
-    ImGui::SameLine();
-    sysid::CreateTooltip(
-        "Here, the units and units per rotation represent what the wheel "
-        "positions and velocities were captured in. The track width value "
-        "will reflect the unit selected here. However, the Kv and Ka will "
-        "always be in Vs/rad and Vs^2 / rad respectively.");
-  }
+      std::string(unit).c_str(), type.name);
 
   if (ImGui::Button("Override Units")) {
     ImGui::OpenPopup("Override Units");
@@ -197,24 +155,11 @@
                  IM_ARRAYSIZE(kUnits));
     unit = kUnits[m_selectedOverrideUnit];
 
-    if (unit == "Degrees") {
-      m_conversionFactor = 360.0;
-    } else if (unit == "Radians") {
-      m_conversionFactor = 2 * std::numbers::pi;
-    } else if (unit == "Rotations") {
-      m_conversionFactor = 1.0;
-    }
-
-    bool isRotational = m_selectedOverrideUnit > 2;
-
     ImGui::SetNextItemWidth(ImGui::GetFontSize() * 7);
-    ImGui::InputDouble(
-        "Units Per Rotation", &m_conversionFactor, 0.0, 0.0, "%.4f",
-        isRotational ? ImGuiInputTextFlags_ReadOnly : ImGuiInputTextFlags_None);
 
     if (ImGui::Button("Close")) {
       ImGui::CloseCurrentPopup();
-      m_manager->OverrideUnits(unit, m_conversionFactor);
+      m_manager->OverrideUnits(unit);
       PrepareData();
     }
 
@@ -234,22 +179,21 @@
   WPI_INFO(m_logger, "{}", "Configuring Params");
   m_stepTestDuration = m_settings.stepTestDuration.to<float>();
 
-  // Estimate qp as 1/8 * units-per-rot
-  m_settings.lqr.qp = 0.125 * m_manager->GetFactor();
+  // Estimate qp as 1/10 native distance unit
+  m_settings.lqr.qp = 0.1;
   // Estimate qv as 1/4 * max velocity = 1/4 * (12V - kS) / kV
   m_settings.lqr.qv = 0.25 * (12.0 - m_ff[0]) / m_ff[1];
 }
 
 void Analyzer::Display() {
-  DisplayFileSelector();
   DisplayGraphs();
 
   switch (m_state) {
-    case AnalyzerState::kWaitingForJSON: {
+    case AnalyzerState::kWaitingForData: {
       ImGui::Text(
           "SysId is currently in theoretical analysis mode.\n"
           "To analyze recorded test data, select a "
-          "data JSON.");
+          "data file (.wpilog).");
       sysid::CreateTooltip(
           "Theoretical feedback gains can be calculated from a "
           "physical model of the mechanism being controlled. "
@@ -295,7 +239,7 @@
     case AnalyzerState::kFileError: {
       CreateErrorPopup(m_errorPopup, m_exception);
       if (!m_errorPopup) {
-        m_state = AnalyzerState::kWaitingForJSON;
+        m_state = AnalyzerState::kWaitingForData;
         return;
       }
       break;
@@ -313,20 +257,10 @@
       break;
     }
   }
-
-  // Periodic functions
-  try {
-    SelectFile();
-  } catch (const AnalysisManager::FileReadingError& e) {
-    m_state = AnalyzerState::kFileError;
-    HandleError(e.what());
-  } catch (const wpi::json::exception& e) {
-    m_state = AnalyzerState::kFileError;
-    HandleError(e.what());
-  }
 }
 
 void Analyzer::PrepareData() {
+  WPI_INFO(m_logger, "{}", "Preparing data");
   try {
     m_manager->PrepareData();
     UpdateFeedforwardGains();
@@ -379,9 +313,6 @@
 void Analyzer::HandleError(std::string_view msg) {
   m_exception = msg;
   m_errorPopup = true;
-  if (m_state == AnalyzerState::kFileError) {
-    m_location = "";
-  }
   PrepareRawGraphs();
 }
 
@@ -458,23 +389,12 @@
   ImGui::End();
 }
 
-void Analyzer::SelectFile() {
-  // If the selector exists and is ready with a result, we can store it.
-  if (m_selector && m_selector->ready() && !m_selector->result().empty()) {
-    // Store the location of the file and reset the selector.
-    WPI_INFO(m_logger, "Opening File: {}", m_selector->result()[0]);
-    m_location = m_selector->result()[0];
-    m_selector.reset();
-    WPI_INFO(m_logger, "{}", "Opened File");
-    m_manager =
-        std::make_unique<AnalysisManager>(m_location, m_settings, m_logger);
-    PrepareData();
-    m_dataset = 0;
-    m_settings.dataset =
-        AnalysisManager::Settings::DrivetrainDataset::kCombined;
-    ConfigParamsOnFileSelect();
-    UpdateFeedbackGains();
-  }
+void Analyzer::AnalyzeData() {
+  m_manager = std::make_unique<AnalysisManager>(m_data, m_settings, m_logger);
+  PrepareData();
+  m_dataset = 0;
+  ConfigParamsOnFileSelect();
+  UpdateFeedbackGains();
 }
 
 void Analyzer::AbortDataPrep() {
@@ -625,8 +545,6 @@
         "This is the angle offset which, when added to the angle measurement, "
         "zeroes it out when the arm is horizontal. This is needed for the arm "
         "feedforward to work.");
-  } else if (m_trackWidth) {
-    DisplayGain("Track Width", &*m_trackWidth);
   }
   double endY = ImGui::GetCursorPosY();
 
@@ -790,7 +708,7 @@
                    IM_ARRAYSIZE(kLoopTypes))) {
     m_settings.type =
         static_cast<FeedbackControllerLoopType>(m_selectedLoopType);
-    if (m_state == AnalyzerState::kWaitingForJSON) {
+    if (m_state == AnalyzerState::kWaitingForData) {
       m_settings.preset.measurementDelay = 0_ms;
     } else {
       if (m_settings.type == FeedbackControllerLoopType::kPosition) {
@@ -817,7 +735,7 @@
 
   if (m_selectedLoopType == 0) {
     std::string unit;
-    if (m_state != AnalyzerState::kWaitingForJSON) {
+    if (m_state != AnalyzerState::kWaitingForData) {
       unit = fmt::format(" ({})", GetAbbreviation(m_manager->GetUnit()));
     }
 
@@ -831,7 +749,7 @@
   }
 
   std::string unit;
-  if (m_state != AnalyzerState::kWaitingForJSON) {
+  if (m_state != AnalyzerState::kWaitingForData) {
     unit = fmt::format(" ({}/s)", GetAbbreviation(m_manager->GetUnit()));
   }
 
diff --git a/sysid/src/main/native/cpp/view/DataSelector.cpp b/sysid/src/main/native/cpp/view/DataSelector.cpp
new file mode 100644
index 0000000..c160490
--- /dev/null
+++ b/sysid/src/main/native/cpp/view/DataSelector.cpp
@@ -0,0 +1,244 @@
+// Copyright (c) FIRST and other WPILib contributors.
+// Open Source Software; you can modify and/or share it under the terms of
+// the WPILib BSD license file in the root directory of this project.
+
+#include "sysid/view/DataSelector.h"
+
+#include <fmt/format.h>
+#include <glass/support/DataLogReaderThread.h>
+#include <imgui.h>
+#include <wpi/DataLogReader.h>
+#include <wpi/Logger.h>
+#include <wpi/StringExtras.h>
+
+#include "sysid/Util.h"
+#include "sysid/analysis/AnalysisType.h"
+#include "sysid/analysis/Storage.h"
+
+using namespace sysid;
+
+static constexpr const char* kAnalysisTypes[] = {"Elevator", "Arm", "Simple"};
+
+static bool EmitEntryTarget(const char* name, bool isString,
+                            const glass::DataLogReaderEntry** entry) {
+  if (*entry) {
+    auto text =
+        fmt::format("{}: {} ({})", name, (*entry)->name, (*entry)->type);
+    ImGui::TextUnformatted(text.c_str());
+  } else {
+    ImGui::Text("%s: <none (DROP HERE)> (%s)", name,
+                isString ? "string" : "number");
+  }
+  bool rv = false;
+  if (ImGui::BeginDragDropTarget()) {
+    if (const ImGuiPayload* payload = ImGui::AcceptDragDropPayload(
+            isString ? "DataLogEntryString" : "DataLogEntry")) {
+      assert(payload->DataSize == sizeof(const glass::DataLogReaderEntry*));
+      *entry = *static_cast<const glass::DataLogReaderEntry**>(payload->Data);
+      rv = true;
+    }
+    ImGui::EndDragDropTarget();
+  }
+  return rv;
+}
+
+void DataSelector::Display() {
+  using namespace std::chrono_literals;
+
+  // building test data is modal (due to async access)
+  if (m_testdataFuture.valid()) {
+    if (m_testdataFuture.wait_for(0s) == std::future_status::ready) {
+      TestData data = m_testdataFuture.get();
+      for (auto&& motordata : data.motorData) {
+        m_testdataStats.emplace_back(
+            fmt::format("Test State: {}", motordata.first()));
+        int i = 0;
+        for (auto&& run : motordata.second.runs) {
+          m_testdataStats.emplace_back(fmt::format(
+              "  Run {} samples: {} Volt {} Pos {} Vel", ++i,
+              run.voltage.size(), run.position.size(), run.velocity.size()));
+        }
+      }
+      if (testdata) {
+        testdata(std::move(data));
+      }
+    }
+    ImGui::Text("Loading data...");
+    return;
+  }
+
+  if (!m_testdataStats.empty()) {
+    for (auto&& line : m_testdataStats) {
+      ImGui::TextUnformatted(line.c_str());
+    }
+    if (ImGui::Button("Ok")) {
+      m_testdataStats.clear();
+    }
+    return;
+  }
+
+  if (EmitEntryTarget("Test State", true, &m_testStateEntry)) {
+    m_testsFuture =
+        std::async(std::launch::async, [testStateEntry = m_testStateEntry] {
+          return LoadTests(*testStateEntry);
+        });
+  }
+
+  if (!m_testStateEntry) {
+    return;
+  }
+
+  if (m_testsFuture.valid() &&
+      m_testsFuture.wait_for(0s) == std::future_status::ready) {
+    m_tests = m_testsFuture.get();
+  }
+
+  if (m_tests.empty()) {
+    if (m_testsFuture.valid()) {
+      ImGui::TextUnformatted("Reading tests...");
+    } else {
+      ImGui::TextUnformatted("No tests found");
+    }
+    return;
+  }
+
+#if 0
+  // Test filtering
+  if (ImGui::BeginCombo("Test", m_selectedTest.c_str())) {
+    for (auto&& test : m_tests) {
+      if (ImGui::Selectable(test.first.c_str(), test.first == m_selectedTest)) {
+        m_selectedTest = test.first;
+      }
+    }
+    ImGui::EndCombo();
+  }
+#endif
+
+  ImGui::Combo("Analysis Type", &m_selectedAnalysis, kAnalysisTypes,
+               IM_ARRAYSIZE(kAnalysisTypes));
+
+  // DND targets
+  EmitEntryTarget("Velocity", false, &m_velocityEntry);
+  EmitEntryTarget("Position", false, &m_positionEntry);
+  EmitEntryTarget("Voltage", false, &m_voltageEntry);
+
+  ImGui::SetNextItemWidth(ImGui::GetFontSize() * 7);
+  ImGui::Combo("Units", &m_selectedUnit, kUnits, IM_ARRAYSIZE(kUnits));
+
+  ImGui::InputDouble("Velocity scaling", &m_velocityScale);
+  ImGui::InputDouble("Position scaling", &m_positionScale);
+
+  if (/*!m_selectedTest.empty() &&*/ m_velocityEntry && m_positionEntry &&
+      m_voltageEntry) {
+    if (ImGui::Button("Load")) {
+      m_testdataFuture =
+          std::async(std::launch::async, [this] { return BuildTestData(); });
+    }
+  }
+}
+
+void DataSelector::Reset() {
+  m_testsFuture = {};
+  m_tests.clear();
+  m_selectedTest.clear();
+  m_testStateEntry = nullptr;
+  m_velocityEntry = nullptr;
+  m_positionEntry = nullptr;
+  m_voltageEntry = nullptr;
+  m_testdataFuture = {};
+}
+
+DataSelector::Tests DataSelector::LoadTests(
+    const glass::DataLogReaderEntry& testStateEntry) {
+  Tests tests;
+  for (auto&& range : testStateEntry.ranges) {
+    std::string_view prevState;
+    Runs* curRuns = nullptr;
+    wpi::log::DataLogReader::iterator lastStart = range.begin();
+    for (auto it = range.begin(), end = range.end(); it != end; ++it) {
+      std::string_view testState;
+      if (it->GetEntry() != testStateEntry.entry ||
+          !it->GetString(&testState)) {
+        continue;
+      }
+
+      // track runs as iterator ranges of the same test
+      if (testState != prevState) {
+        if (curRuns) {
+          curRuns->emplace_back(lastStart, it);
+        }
+        lastStart = it;
+      }
+      prevState = testState;
+
+      if (testState == "none") {
+        curRuns = nullptr;
+        continue;
+      }
+
+      auto [testName, direction] = wpi::rsplit(testState, '-');
+      auto testIt = tests.find(testName);
+      if (testIt == tests.end()) {
+        testIt = tests.emplace(std::string{testName}, State{}).first;
+      }
+      auto stateIt = testIt->second.find(testState);
+      if (stateIt == testIt->second.end()) {
+        stateIt = testIt->second.emplace(std::string{testState}, Runs{}).first;
+      }
+      curRuns = &stateIt->second;
+    }
+
+    if (curRuns) {
+      curRuns->emplace_back(lastStart, range.end());
+    }
+  }
+  return tests;
+}
+
+template <typename T>
+static void AddSample(std::vector<MotorData::Run::Sample<T>>& samples,
+                      const wpi::log::DataLogRecord& record, bool isDouble,
+                      double scale) {
+  if (isDouble) {
+    double val;
+    if (record.GetDouble(&val)) {
+      samples.emplace_back(units::second_t{record.GetTimestamp() * 1.0e-6},
+                           T{val * scale});
+    }
+  } else {
+    float val;
+    if (record.GetFloat(&val)) {
+      samples.emplace_back(units::second_t{record.GetTimestamp() * 1.0e-6},
+                           T{static_cast<double>(val * scale)});
+    }
+  }
+}
+
+TestData DataSelector::BuildTestData() {
+  TestData data;
+  data.distanceUnit = kUnits[m_selectedUnit];
+  data.mechanismType = analysis::FromName(kAnalysisTypes[m_selectedAnalysis]);
+  bool voltageDouble = m_voltageEntry->type == "double";
+  bool positionDouble = m_positionEntry->type == "double";
+  bool velocityDouble = m_velocityEntry->type == "double";
+
+  for (auto&& test : m_tests) {
+    for (auto&& state : test.second) {
+      auto& motorData = data.motorData[state.first];
+      for (auto&& range : state.second) {
+        auto& run = motorData.runs.emplace_back();
+        for (auto&& record : range) {
+          if (record.GetEntry() == m_voltageEntry->entry) {
+            AddSample(run.voltage, record, voltageDouble, 1.0);
+          } else if (record.GetEntry() == m_positionEntry->entry) {
+            AddSample(run.position, record, positionDouble, m_positionScale);
+          } else if (record.GetEntry() == m_velocityEntry->entry) {
+            AddSample(run.velocity, record, velocityDouble, m_velocityScale);
+          }
+        }
+      }
+    }
+  }
+
+  return data;
+}
diff --git a/sysid/src/main/native/cpp/view/JSONConverter.cpp b/sysid/src/main/native/cpp/view/JSONConverter.cpp
deleted file mode 100644
index 88eaa6a..0000000
--- a/sysid/src/main/native/cpp/view/JSONConverter.cpp
+++ /dev/null
@@ -1,64 +0,0 @@
-// Copyright (c) FIRST and other WPILib contributors.
-// Open Source Software; you can modify and/or share it under the terms of
-// the WPILib BSD license file in the root directory of this project.
-
-#include "sysid/analysis/JSONConverter.h"
-#include "sysid/view/JSONConverter.h"
-
-#include <exception>
-
-#include <imgui.h>
-#include <portable-file-dialogs.h>
-#include <wpi/timestamp.h>
-
-#include "sysid/Util.h"
-
-using namespace sysid;
-
-void JSONConverter::DisplayConverter(
-    const char* tooltip,
-    std::function<std::string(std::string_view, wpi::Logger&)> converter) {
-  if (ImGui::Button(tooltip)) {
-    m_opener = std::make_unique<pfd::open_file>(
-        tooltip, "", std::vector<std::string>{"JSON File", SYSID_PFD_JSON_EXT});
-  }
-
-  if (m_opener && m_opener->ready()) {
-    if (!m_opener->result().empty()) {
-      m_location = m_opener->result()[0];
-      try {
-        converter(m_location, m_logger);
-        m_timestamp = wpi::Now() * 1E-6;
-      } catch (const std::exception& e) {
-        ImGui::OpenPopup("Exception Caught!");
-        m_exception = e.what();
-      }
-    }
-    m_opener.reset();
-  }
-
-  if (wpi::Now() * 1E-6 - m_timestamp < 5) {
-    ImGui::SameLine();
-    ImGui::Text("Saved!");
-  }
-
-  // Handle exceptions.
-  ImGui::SetNextWindowSize(ImVec2(480.f, 0.0f));
-  if (ImGui::BeginPopupModal("Exception Caught!")) {
-    ImGui::PushTextWrapPos(0.0f);
-    ImGui::Text(
-        "An error occurred when parsing the JSON. This most likely means that "
-        "the JSON data is incorrectly formatted.");
-    ImGui::TextColored(ImVec4(1.0f, 0.4f, 0.4f, 1.0f), "%s",
-                       m_exception.c_str());
-    ImGui::PopTextWrapPos();
-    if (ImGui::Button("Close")) {
-      ImGui::CloseCurrentPopup();
-    }
-    ImGui::EndPopup();
-  }
-}
-
-void JSONConverter::DisplayCSVConvert() {
-  DisplayConverter("Select SysId JSON", sysid::ToCSV);
-}
diff --git a/sysid/src/main/native/cpp/view/LogLoader.cpp b/sysid/src/main/native/cpp/view/LogLoader.cpp
new file mode 100644
index 0000000..fdaa3af
--- /dev/null
+++ b/sysid/src/main/native/cpp/view/LogLoader.cpp
@@ -0,0 +1,208 @@
+// Copyright (c) FIRST and other WPILib contributors.
+// Open Source Software; you can modify and/or share it under the terms of
+// the WPILib BSD license file in the root directory of this project.
+
+#include "sysid/view/LogLoader.h"
+
+#include <algorithm>
+#include <memory>
+#include <span>
+#include <string_view>
+
+#include <glass/support/DataLogReaderThread.h>
+#include <imgui.h>
+#include <imgui_stdlib.h>
+#include <portable-file-dialogs.h>
+#include <wpi/SpanExtras.h>
+#include <wpi/StringExtras.h>
+#include <wpi/fs.h>
+
+using namespace sysid;
+
+LogLoader::LogLoader(glass::Storage& storage, wpi::Logger& logger) {}
+
+LogLoader::~LogLoader() = default;
+
+void LogLoader::Display() {
+  if (ImGui::Button("Open data log file...")) {
+    m_opener = std::make_unique<pfd::open_file>(
+        "Select Data Log", "",
+        std::vector<std::string>{"DataLog Files", "*.wpilog"});
+  }
+
+  // Handle opening the file
+  if (m_opener && m_opener->ready(0)) {
+    if (!m_opener->result().empty()) {
+      m_filename = m_opener->result()[0];
+
+      std::error_code ec;
+      auto buf = wpi::MemoryBuffer::GetFile(m_filename, ec);
+      if (ec) {
+        ImGui::OpenPopup("Error");
+        m_error = fmt::format("Could not open file: {}", ec.message());
+        return;
+      }
+
+      wpi::log::DataLogReader reader{std::move(buf)};
+      if (!reader.IsValid()) {
+        ImGui::OpenPopup("Error");
+        m_error = "Not a valid datalog file";
+        return;
+      }
+      unload();
+      m_reader =
+          std::make_unique<glass::DataLogReaderThread>(std::move(reader));
+      m_entryTree.clear();
+    }
+    m_opener.reset();
+  }
+
+  // Handle errors
+  ImGui::SetNextWindowSize(ImVec2(480.f, 0.0f));
+  if (ImGui::BeginPopupModal("Error")) {
+    ImGui::PushTextWrapPos(0.0f);
+    ImGui::TextUnformatted(m_error.c_str());
+    ImGui::PopTextWrapPos();
+    if (ImGui::Button("Close")) {
+      ImGui::CloseCurrentPopup();
+    }
+    ImGui::EndPopup();
+  }
+
+  if (!m_reader) {
+    return;
+  }
+
+  // Summary info
+  ImGui::TextUnformatted(fs::path{m_filename}.stem().string().c_str());
+  ImGui::Text("%u records, %u entries%s", m_reader->GetNumRecords(),
+              m_reader->GetNumEntries(),
+              m_reader->IsDone() ? "" : " (working)");
+
+  if (!m_reader->IsDone()) {
+    return;
+  }
+
+  bool refilter = ImGui::InputText("Filter", &m_filter);
+
+  // Display tree of entries
+  if (m_entryTree.empty() || refilter) {
+    RebuildEntryTree();
+  }
+
+  ImGui::BeginTable(
+      "Entries", 2,
+      ImGuiTableFlags_Borders | ImGuiTableFlags_SizingStretchProp);
+  ImGui::TableSetupColumn("Name");
+  ImGui::TableSetupColumn("Type");
+  // ImGui::TableSetupColumn("Metadata");
+  ImGui::TableHeadersRow();
+  DisplayEntryTree(m_entryTree);
+  ImGui::EndTable();
+}
+
+void LogLoader::RebuildEntryTree() {
+  m_entryTree.clear();
+  wpi::SmallVector<std::string_view, 16> parts;
+  m_reader->ForEachEntryName([&](const glass::DataLogReaderEntry& entry) {
+    // only show double/float/string entries (TODO: support struct/protobuf)
+    if (entry.type != "double" && entry.type != "float" &&
+        entry.type != "string") {
+      return;
+    }
+
+    // filter on name
+    if (!m_filter.empty() && !wpi::contains_lower(entry.name, m_filter)) {
+      return;
+    }
+
+    parts.clear();
+    // split on first : if one is present
+    auto [prefix, mainpart] = wpi::split(entry.name, ':');
+    if (mainpart.empty() || wpi::contains(prefix, '/')) {
+      mainpart = entry.name;
+    } else {
+      parts.emplace_back(prefix);
+    }
+    wpi::split(mainpart, parts, '/', -1, false);
+
+    // ignore a raw "/" key
+    if (parts.empty()) {
+      return;
+    }
+
+    // get to leaf
+    auto nodes = &m_entryTree;
+    for (auto part : wpi::drop_back(std::span{parts.begin(), parts.end()})) {
+      auto it =
+          std::find_if(nodes->begin(), nodes->end(),
+                       [&](const auto& node) { return node.name == part; });
+      if (it == nodes->end()) {
+        nodes->emplace_back(part);
+        // path is from the beginning of the string to the end of the current
+        // part; this works because part is a reference to the internals of
+        // entry.name
+        nodes->back().path.assign(
+            entry.name.data(), part.data() + part.size() - entry.name.data());
+        it = nodes->end() - 1;
+      }
+      nodes = &it->children;
+    }
+
+    auto it = std::find_if(nodes->begin(), nodes->end(), [&](const auto& node) {
+      return node.name == parts.back();
+    });
+    if (it == nodes->end()) {
+      nodes->emplace_back(parts.back());
+      // no need to set path, as it's identical to entry.name
+      it = nodes->end() - 1;
+    }
+    it->entry = &entry;
+  });
+}
+
+static void EmitEntry(const std::string& name,
+                      const glass::DataLogReaderEntry& entry) {
+  ImGui::TableNextColumn();
+  ImGui::Selectable(name.c_str());
+  if (ImGui::BeginDragDropSource()) {
+    auto entryPtr = &entry;
+    ImGui::SetDragDropPayload(
+        entry.type == "string" ? "DataLogEntryString" : "DataLogEntry",
+        &entryPtr,
+        sizeof(entryPtr));  // NOLINT
+    ImGui::TextUnformatted(entry.name.data(),
+                           entry.name.data() + entry.name.size());
+    ImGui::EndDragDropSource();
+  }
+  ImGui::TableNextColumn();
+  ImGui::TextUnformatted(entry.type.data(),
+                         entry.type.data() + entry.type.size());
+#if 0
+  ImGui::TableNextColumn();
+  ImGui::TextUnformatted(entry.metadata.data(),
+                         entry.metadata.data() + entry.metadata.size());
+#endif
+}
+
+void LogLoader::DisplayEntryTree(const std::vector<EntryTreeNode>& tree) {
+  for (auto&& node : tree) {
+    if (node.entry) {
+      EmitEntry(node.name, *node.entry);
+    }
+
+    if (!node.children.empty()) {
+      ImGui::TableNextColumn();
+      bool open = ImGui::TreeNodeEx(node.name.c_str(),
+                                    ImGuiTreeNodeFlags_SpanFullWidth);
+      ImGui::TableNextColumn();
+#if 0
+      ImGui::TableNextColumn();
+#endif
+      if (open) {
+        DisplayEntryTree(node.children);
+        ImGui::TreePop();
+      }
+    }
+  }
+}
diff --git a/sysid/src/main/native/cpp/view/Logger.cpp b/sysid/src/main/native/cpp/view/Logger.cpp
deleted file mode 100644
index 5e7773d..0000000
--- a/sysid/src/main/native/cpp/view/Logger.cpp
+++ /dev/null
@@ -1,222 +0,0 @@
-// Copyright (c) FIRST and other WPILib contributors.
-// Open Source Software; you can modify and/or share it under the terms of
-// the WPILib BSD license file in the root directory of this project.
-
-#include "sysid/view/Logger.h"
-
-#include <exception>
-#include <numbers>
-
-#include <glass/Context.h>
-#include <glass/Storage.h>
-#include <imgui.h>
-#include <imgui_internal.h>
-#include <imgui_stdlib.h>
-#include <networktables/NetworkTable.h>
-#include <units/angle.h>
-#include <wpigui.h>
-
-#include "sysid/Util.h"
-#include "sysid/analysis/AnalysisType.h"
-#include "sysid/view/UILayout.h"
-
-using namespace sysid;
-
-Logger::Logger(glass::Storage& storage, wpi::Logger& logger)
-    : m_logger{logger}, m_ntSettings{"sysid", storage} {
-  wpi::gui::AddEarlyExecute([&] { m_ntSettings.Update(); });
-
-  m_ntSettings.EnableServerOption(false);
-}
-
-void Logger::Display() {
-  // Get the current width of the window. This will be used to scale
-  // our UI elements.
-  float width = ImGui::GetContentRegionAvail().x;
-
-  // Add team number input and apply button for NT connection.
-  m_ntSettings.Display();
-
-  // Reset and clear the internal manager state.
-  ImGui::SameLine();
-  if (ImGui::Button("Reset Telemetry")) {
-    m_settings = TelemetryManager::Settings{};
-    m_manager = std::make_unique<TelemetryManager>(m_settings, m_logger);
-    m_settings.mechanism = analysis::FromName(kTypes[m_selectedType]);
-  }
-
-  // Add NT connection indicator.
-  static ImVec4 kColorDisconnected{1.0f, 0.4f, 0.4f, 1.0f};
-  static ImVec4 kColorConnected{0.2f, 1.0f, 0.2f, 1.0f};
-  ImGui::SameLine();
-  bool ntConnected = nt::NetworkTableInstance::GetDefault().IsConnected();
-  ImGui::TextColored(ntConnected ? kColorConnected : kColorDisconnected,
-                     ntConnected ? "NT Connected" : "NT Disconnected");
-
-  // Create a Section for project configuration
-  ImGui::Separator();
-  ImGui::Spacing();
-  ImGui::Text("Project Parameters");
-
-  // Add a dropdown for mechanism type.
-  ImGui::SetNextItemWidth(ImGui::GetFontSize() * kTextBoxWidthMultiple);
-
-  if (ImGui::Combo("Mechanism", &m_selectedType, kTypes,
-                   IM_ARRAYSIZE(kTypes))) {
-    m_settings.mechanism = analysis::FromName(kTypes[m_selectedType]);
-  }
-
-  // Add Dropdown for Units
-  ImGui::SetNextItemWidth(ImGui::GetFontSize() * kTextBoxWidthMultiple);
-  if (ImGui::Combo("Unit Type", &m_selectedUnit, kUnits,
-                   IM_ARRAYSIZE(kUnits))) {
-    m_settings.units = kUnits[m_selectedUnit];
-  }
-
-  sysid::CreateTooltip(
-      "This is the type of units that your gains will be in. For example, if "
-      "you want your flywheel gains in terms of radians, then use the radians "
-      "unit. On the other hand, if your drivetrain will use gains in meters, "
-      "choose meters.");
-
-  // Rotational units have fixed Units per rotations
-  m_isRotationalUnits =
-      (m_settings.units == "Rotations" || m_settings.units == "Degrees" ||
-       m_settings.units == "Radians");
-  if (m_settings.units == "Degrees") {
-    m_settings.unitsPerRotation = 360.0;
-  } else if (m_settings.units == "Radians") {
-    m_settings.unitsPerRotation = 2 * std::numbers::pi;
-  } else if (m_settings.units == "Rotations") {
-    m_settings.unitsPerRotation = 1.0;
-  }
-
-  // Units Per Rotations entry
-  ImGui::SetNextItemWidth(ImGui::GetFontSize() * kTextBoxWidthMultiple);
-  ImGui::InputDouble("Units Per Rotation", &m_settings.unitsPerRotation, 0.0f,
-                     0.0f, "%.4f",
-                     m_isRotationalUnits ? ImGuiInputTextFlags_ReadOnly
-                                         : ImGuiInputTextFlags_None);
-  sysid::CreateTooltip(
-      "The logger assumes that the code will be sending recorded motor shaft "
-      "rotations over NetworkTables. This value will then be multiplied by the "
-      "units per rotation to get the measurement in the units you "
-      "specified.\n\nFor non-rotational units (e.g. meters), this value is "
-      "usually the wheel diameter times pi (should not include gearing).");
-  // Create a section for voltage parameters.
-  ImGui::Separator();
-  ImGui::Spacing();
-  ImGui::Text("Voltage Parameters");
-
-  auto CreateVoltageParameters = [this](const char* text, double* data,
-                                        float min, float max) {
-    ImGui::SetNextItemWidth(ImGui::GetFontSize() * 6);
-    ImGui::PushItemFlag(ImGuiItemFlags_Disabled,
-                        m_manager && m_manager->IsActive());
-    float value = static_cast<float>(*data);
-    if (ImGui::SliderFloat(text, &value, min, max, "%.2f")) {
-      *data = value;
-    }
-    ImGui::PopItemFlag();
-  };
-
-  CreateVoltageParameters("Quasistatic Ramp Rate (V/s)",
-                          &m_settings.quasistaticRampRate, 0.10f, 0.60f);
-  sysid::CreateTooltip(
-      "This is the rate at which the voltage will increase during the "
-      "quasistatic test.");
-
-  CreateVoltageParameters("Dynamic Step Voltage (V)", &m_settings.stepVoltage,
-                          0.0f, 10.0f);
-  sysid::CreateTooltip(
-      "This is the voltage that will be applied for the "
-      "dynamic voltage (acceleration) tests.");
-
-  // Create a section for tests.
-  ImGui::Separator();
-  ImGui::Spacing();
-  ImGui::Text("Tests");
-
-  auto CreateTest = [this, width](const char* text, const char* itext) {
-    // Display buttons if we have an NT connection.
-    if (nt::NetworkTableInstance::GetDefault().IsConnected()) {
-      // Create button to run tests.
-      if (ImGui::Button(text)) {
-        // Open the warning message.
-        ImGui::OpenPopup("Warning");
-        m_manager->BeginTest(itext);
-        m_opened = text;
-      }
-      if (m_opened == text && ImGui::BeginPopupModal("Warning")) {
-        ImGui::TextWrapped("%s", m_popupText.c_str());
-        if (ImGui::Button(m_manager->IsActive() ? "End Test" : "Close")) {
-          m_manager->EndTest();
-          ImGui::CloseCurrentPopup();
-          m_opened = "";
-        }
-        ImGui::EndPopup();
-      }
-    } else {
-      // Show disabled text when there is no connection.
-      ImGui::TextDisabled("%s", text);
-    }
-
-    // Show whether the tests were run or not.
-    bool run = m_manager->HasRunTest(itext);
-    ImGui::SameLine(width * 0.7);
-    ImGui::Text(run ? "Run" : "Not Run");
-  };
-
-  CreateTest("Quasistatic Forward", "slow-forward");
-  CreateTest("Quasistatic Backward", "slow-backward");
-  CreateTest("Dynamic Forward", "fast-forward");
-  CreateTest("Dynamic Backward", "fast-backward");
-
-  m_manager->RegisterDisplayCallback(
-      [this](const auto& str) { m_popupText = str; });
-
-  // Display the path to where the JSON will be saved and a button to select the
-  // location.
-  ImGui::Separator();
-  ImGui::Spacing();
-  ImGui::Text("Save Location");
-  if (ImGui::Button("Choose")) {
-    m_selector = std::make_unique<pfd::select_folder>("Select Folder");
-  }
-  ImGui::SameLine();
-  ImGui::InputText("##savelocation", &m_jsonLocation,
-                   ImGuiInputTextFlags_ReadOnly);
-
-  // Add button to save.
-  ImGui::SameLine(width * 0.9);
-  if (ImGui::Button("Save")) {
-    try {
-      m_manager->SaveJSON(m_jsonLocation);
-    } catch (const std::exception& e) {
-      ImGui::OpenPopup("Exception Caught!");
-      m_exception = e.what();
-    }
-  }
-
-  // Handle exceptions.
-  if (ImGui::BeginPopupModal("Exception Caught!")) {
-    ImGui::Text("%s", m_exception.c_str());
-    if (ImGui::Button("Close")) {
-      ImGui::CloseCurrentPopup();
-    }
-    ImGui::EndPopup();
-  }
-
-  // Run periodic methods.
-  SelectDataFolder();
-  m_ntSettings.Update();
-  m_manager->Update();
-}
-
-void Logger::SelectDataFolder() {
-  // If the selector exists and is ready with a result, we can store it.
-  if (m_selector && m_selector->ready()) {
-    m_jsonLocation = m_selector->result();
-    m_selector.reset();
-  }
-}