Creates directory and file structure for y2020

Based of the 2019 robot and modified to be a boilerplate for a
new robot.

Change-Id: I7e2861a3cfa0b7ca608d5068f731b2796a97fffe
diff --git a/y2020/control_loops/drivetrain/BUILD b/y2020/control_loops/drivetrain/BUILD
new file mode 100644
index 0000000..d03c1b9
--- /dev/null
+++ b/y2020/control_loops/drivetrain/BUILD
@@ -0,0 +1,83 @@
+load("@com_github_google_flatbuffers//:build_defs.bzl", "flatbuffer_cc_library")
+load("//tools/build_rules:select.bzl", "compiler_select", "cpu_select")
+
+genrule(
+    name = "genrule_drivetrain",
+    outs = [
+        "drivetrain_dog_motor_plant.h",
+        "drivetrain_dog_motor_plant.cc",
+        "kalman_drivetrain_motor_plant.h",
+        "kalman_drivetrain_motor_plant.cc",
+    ],
+    cmd = "$(location //y2020/control_loops/python:drivetrain) $(OUTS)",
+    tools = [
+        "//y2020/control_loops/python:drivetrain",
+    ],
+)
+
+genrule(
+    name = "genrule_polydrivetrain",
+    outs = [
+        "polydrivetrain_dog_motor_plant.h",
+        "polydrivetrain_dog_motor_plant.cc",
+        "polydrivetrain_cim_plant.h",
+        "polydrivetrain_cim_plant.cc",
+        "hybrid_velocity_drivetrain.h",
+        "hybrid_velocity_drivetrain.cc",
+    ],
+    cmd = "$(location //y2020/control_loops/python:polydrivetrain) $(OUTS)",
+    tools = [
+        "//y2020/control_loops/python:polydrivetrain",
+    ],
+)
+
+cc_library(
+    name = "polydrivetrain_plants",
+    srcs = [
+        "drivetrain_dog_motor_plant.cc",
+        "hybrid_velocity_drivetrain.cc",
+        "kalman_drivetrain_motor_plant.cc",
+        "polydrivetrain_dog_motor_plant.cc",
+    ],
+    hdrs = [
+        "drivetrain_dog_motor_plant.h",
+        "hybrid_velocity_drivetrain.h",
+        "kalman_drivetrain_motor_plant.h",
+        "polydrivetrain_dog_motor_plant.h",
+    ],
+    visibility = ["//visibility:public"],
+    deps = [
+        "//frc971/control_loops:hybrid_state_feedback_loop",
+        "//frc971/control_loops:state_feedback_loop",
+    ],
+)
+
+cc_library(
+    name = "drivetrain_base",
+    srcs = [
+        "drivetrain_base.cc",
+    ],
+    hdrs = [
+        "drivetrain_base.h",
+    ],
+    visibility = ["//visibility:public"],
+    deps = [
+        ":polydrivetrain_plants",
+        "//frc971:shifter_hall_effect",
+        "//frc971/control_loops/drivetrain:drivetrain_config",
+    ],
+)
+
+cc_binary(
+    name = "drivetrain",
+    srcs = [
+        "drivetrain_main.cc",
+    ],
+    visibility = ["//visibility:public"],
+    deps = [
+        ":drivetrain_base",
+        "//aos:init",
+        "//aos/events:shm_event_loop",
+        "//frc971/control_loops/drivetrain:drivetrain_lib",
+    ],
+)
diff --git a/y2020/control_loops/drivetrain/drivetrain_base.cc b/y2020/control_loops/drivetrain/drivetrain_base.cc
new file mode 100644
index 0000000..c3597f5
--- /dev/null
+++ b/y2020/control_loops/drivetrain/drivetrain_base.cc
@@ -0,0 +1,63 @@
+#include "y2020/control_loops/drivetrain/drivetrain_base.h"
+
+#include <chrono>
+
+#include "frc971/control_loops/drivetrain/drivetrain_config.h"
+#include "frc971/control_loops/state_feedback_loop.h"
+#include "y2020/control_loops/drivetrain/drivetrain_dog_motor_plant.h"
+#include "y2020/control_loops/drivetrain/hybrid_velocity_drivetrain.h"
+#include "y2020/control_loops/drivetrain/kalman_drivetrain_motor_plant.h"
+#include "y2020/control_loops/drivetrain/polydrivetrain_dog_motor_plant.h"
+
+using ::frc971::control_loops::drivetrain::DrivetrainConfig;
+
+namespace chrono = ::std::chrono;
+
+namespace y2020 {
+namespace control_loops {
+namespace drivetrain {
+
+using ::frc971::constants::ShifterHallEffect;
+
+const ShifterHallEffect kThreeStateDriveShifter{0.0, 0.0, 0.25, 0.75};
+
+const DrivetrainConfig<double> &GetDrivetrainConfig() {
+  static DrivetrainConfig<double> kDrivetrainConfig{
+      ::frc971::control_loops::drivetrain::ShifterType::SIMPLE_SHIFTER,
+      ::frc971::control_loops::drivetrain::LoopType::CLOSED_LOOP,
+      ::frc971::control_loops::drivetrain::GyroType::IMU_Z_GYRO,
+      ::frc971::control_loops::drivetrain::IMUType::IMU_FLIPPED_X,
+
+      drivetrain::MakeDrivetrainLoop,
+      drivetrain::MakeVelocityDrivetrainLoop,
+      drivetrain::MakeKFDrivetrainLoop,
+      drivetrain::MakeHybridVelocityDrivetrainLoop,
+
+      chrono::duration_cast<chrono::nanoseconds>(
+          chrono::duration<double>(drivetrain::kDt)),
+      drivetrain::kRobotRadius,
+      drivetrain::kWheelRadius,
+      drivetrain::kV,
+
+      drivetrain::kHighGearRatio,
+      drivetrain::kLowGearRatio,
+      drivetrain::kJ,
+      drivetrain::kMass,
+      kThreeStateDriveShifter,
+      kThreeStateDriveShifter,
+      true /* default_high_gear */,
+      0 /* down_offset if using constants use
+     constants::GetValues().down_error */
+      ,
+      0.7 /* wheel_non_linearity */,
+      1.2 /* quickturn_wheel_multiplier */,
+      1.2 /* wheel_multiplier */,
+      true /*pistol_grip_shift_enables_line_follow*/,
+  };
+
+  return kDrivetrainConfig;
+};
+
+}  // namespace drivetrain
+}  // namespace control_loops
+}  // namespace y2020
diff --git a/y2020/control_loops/drivetrain/drivetrain_base.h b/y2020/control_loops/drivetrain/drivetrain_base.h
new file mode 100644
index 0000000..c220088
--- /dev/null
+++ b/y2020/control_loops/drivetrain/drivetrain_base.h
@@ -0,0 +1,17 @@
+#ifndef y2020_CONTROL_LOOPS_DRIVETRAIN_DRIVETRAIN_BASE_H_
+#define y2020_CONTROL_LOOPS_DRIVETRAIN_DRIVETRAIN_BASE_H_
+
+#include "frc971/control_loops/drivetrain/drivetrain_config.h"
+
+namespace y2020 {
+namespace control_loops {
+namespace drivetrain {
+
+const ::frc971::control_loops::drivetrain::DrivetrainConfig<double>
+    &GetDrivetrainConfig();
+
+}  // namespace drivetrain
+}  // namespace control_loops
+}  // namespace y2020
+
+#endif  // y2020_CONTROL_LOOPS_DRIVETRAIN_DRIVETRAIN_BASE_H_
diff --git a/y2020/control_loops/drivetrain/drivetrain_main.cc b/y2020/control_loops/drivetrain/drivetrain_main.cc
new file mode 100644
index 0000000..66b9cc7
--- /dev/null
+++ b/y2020/control_loops/drivetrain/drivetrain_main.cc
@@ -0,0 +1,25 @@
+#include "aos/events/shm_event_loop.h"
+#include "aos/init.h"
+#include "frc971/control_loops/drivetrain/drivetrain.h"
+#include "y2020/control_loops/drivetrain/drivetrain_base.h"
+
+using ::frc971::control_loops::drivetrain::DrivetrainLoop;
+
+int main() {
+  ::aos::InitNRT(true);
+
+  aos::FlatbufferDetachedBuffer<aos::Configuration> config =
+      aos::configuration::ReadConfig("config.json");
+
+  ::aos::ShmEventLoop event_loop(&config.message());
+  ::frc971::control_loops::drivetrain::DeadReckonEkf localizer(
+      &event_loop, ::y2020::control_loops::drivetrain::GetDrivetrainConfig());
+  DrivetrainLoop drivetrain(
+      ::y2020::control_loops::drivetrain::GetDrivetrainConfig(), &event_loop,
+      &localizer);
+
+  event_loop.Run();
+
+  ::aos::Cleanup();
+  return 0;
+}