diff --git a/y2023/control_loops/superstructure/arm/BUILD b/y2023/control_loops/superstructure/arm/BUILD
index dc52f02..c125fac 100644
--- a/y2023/control_loops/superstructure/arm/BUILD
+++ b/y2023/control_loops/superstructure/arm/BUILD
@@ -62,3 +62,19 @@
         "//frc971/control_loops/double_jointed_arm:dynamics",
     ],
 )
+
+cc_binary(
+    name = "arm_design",
+    srcs = [
+        "arm_design.cc",
+    ],
+    target_compatible_with = ["@platforms//os:linux"],
+    deps = [
+        ":arm_constants",
+        "//aos:init",
+        "//frc971/analysis:in_process_plotter",
+        "//frc971/control_loops:dlqr",
+        "//frc971/control_loops:jacobian",
+        "//frc971/control_loops/double_jointed_arm:dynamics",
+    ],
+)
diff --git a/y2023/control_loops/superstructure/arm/arm_constants.h b/y2023/control_loops/superstructure/arm/arm_constants.h
index 5611eaa..39e146f 100644
--- a/y2023/control_loops/superstructure/arm/arm_constants.h
+++ b/y2023/control_loops/superstructure/arm/arm_constants.h
@@ -14,23 +14,23 @@
 constexpr double kStallCurrent = 257.0;
 
 constexpr ::frc971::control_loops::arm::ArmConstants kArmConstants = {
-    .l1 = 20 * 0.0254,
-    .l2 = 38 * 0.0254,
+    .l0 = 20 * 0.0254,
+    .l1 = 38 * 0.0254,
 
-    .m1 = 9.34 / 2.2,
-    .m2 = 9.77 / 2.2,
+    .m0 = 9.34 / 2.2,
+    .m1 = 9.77 / 2.2,
 
     // Moment of inertia of the joints in kg m^2
-    .j1 = 2957.05 * 0.0002932545454545454,
-    .j2 = 2824.70 * 0.0002932545454545454,
+    .j0 = 2957.05 * 0.0002932545454545454,
+    .j1 = 2824.70 * 0.0002932545454545454,
 
     // Radius of the center of mass of the joints in meters.
-    .r1 = 21.64 * 0.0254,
-    .r2 = 26.70 * 0.0254,
+    .r0 = 21.64 * 0.0254,
+    .r1 = 26.70 * 0.0254,
 
     // Gear ratios for the two joints.
-    .g1 = 55.0,
-    .g2 = 106.0,
+    .g0 = 55.0,
+    .g1 = 106.0,
 
     // Falcon motor constants.
     .efficiency_tweak = kEfficiencyTweak,
diff --git a/y2023/control_loops/superstructure/arm/arm_design.cc b/y2023/control_loops/superstructure/arm/arm_design.cc
new file mode 100644
index 0000000..99ffa2c
--- /dev/null
+++ b/y2023/control_loops/superstructure/arm/arm_design.cc
@@ -0,0 +1,193 @@
+#include "aos/init.h"
+#include "frc971/analysis/in_process_plotter.h"
+#include "frc971/control_loops/dlqr.h"
+#include "frc971/control_loops/double_jointed_arm/dynamics.h"
+#include "frc971/control_loops/jacobian.h"
+#include "y2023/control_loops/superstructure/arm/arm_constants.h"
+
+DEFINE_double(lqr_proximal_pos, 0.15, "Position LQR gain");
+DEFINE_double(lqr_proximal_vel, 4.0, "Velocity LQR gain");
+DEFINE_double(lqr_distal_pos, 0.20, "Position LQR gain");
+DEFINE_double(lqr_distal_vel, 4.0, "Velocity LQR gain");
+DEFINE_double(fx, 0.0, "X force");
+DEFINE_double(fy, 0.0, "y force");
+
+DEFINE_double(start0, 0.0, "starting position on proximal");
+DEFINE_double(start1, 0.0, "starting position on distal");
+DEFINE_double(goal0, 0.0, "goal position on proximal");
+DEFINE_double(goal1, 0.0, "goal position on distal");
+
+namespace y2023 {
+namespace control_loops {
+namespace superstructure {
+namespace arm {
+
+int Main() {
+  frc971::analysis::Plotter plotter;
+
+  frc971::control_loops::arm::Dynamics dynamics(kArmConstants);
+
+  ::Eigen::Matrix<double, 4, 1> X = ::Eigen::Matrix<double, 4, 1>::Zero();
+  ::Eigen::Matrix<double, 4, 1> goal = ::Eigen::Matrix<double, 4, 1>::Zero();
+  goal(0, 0) = FLAGS_goal0;
+  goal(1, 0) = 0;
+  goal(2, 0) = FLAGS_goal1;
+  goal(3, 0) = 0;
+
+  X(0, 0) = FLAGS_start0;
+  X(1, 0) = 0;
+  X(2, 0) = FLAGS_start1;
+  X(3, 0) = 0;
+  ::Eigen::Matrix<double, 2, 1> U = ::Eigen::Matrix<double, 2, 1>::Zero();
+
+  constexpr double kDt = 0.00505;
+
+  std::vector<double> t;
+  std::vector<double> x0;
+  std::vector<double> x1;
+  std::vector<double> x2;
+  std::vector<double> x3;
+  std::vector<double> u0;
+  std::vector<double> u1;
+
+  std::vector<double> current0;
+  std::vector<double> current1;
+  std::vector<double> torque0;
+  std::vector<double> torque1;
+
+  const double kProximalPosLQR = FLAGS_lqr_proximal_pos;
+  const double kProximalVelLQR = FLAGS_lqr_proximal_vel;
+  const double kDistalPosLQR = FLAGS_lqr_distal_pos;
+  const double kDistalVelLQR = FLAGS_lqr_distal_vel;
+  const ::Eigen::DiagonalMatrix<double, 4> Q =
+      (::Eigen::DiagonalMatrix<double, 4>().diagonal()
+           << 1.0 / ::std::pow(kProximalPosLQR, 2),
+       1.0 / ::std::pow(kProximalVelLQR, 2), 1.0 / ::std::pow(kDistalPosLQR, 2),
+       1.0 / ::std::pow(kDistalVelLQR, 2))
+          .finished()
+          .asDiagonal();
+
+  const ::Eigen::DiagonalMatrix<double, 2> R =
+      (::Eigen::DiagonalMatrix<double, 2>().diagonal()
+           << 1.0 / ::std::pow(12.0, 2),
+       1.0 / ::std::pow(12.0, 2))
+          .finished()
+          .asDiagonal();
+
+  {
+    const ::Eigen::Matrix<double, 2, 1> torque =
+        dynamics
+            .TorqueFromForce(X,
+                             ::Eigen::Matrix<double, 2, 1>(FLAGS_fx, FLAGS_fy))
+            .transpose();
+    LOG(INFO) << "Torque (N m): " << torque.transpose();
+    const ::Eigen::Matrix<double, 2, 1> current =
+        dynamics.CurrentFromTorque(torque);
+
+    LOG(INFO) << "Current (Amps): " << current.transpose();
+
+    ::Eigen::Matrix<double, 2, 1> battery_current;
+    battery_current(0) =
+        current(0) * current(0) * kArmConstants.resistance / 12.0;
+    battery_current(1) =
+        current(1) * current(1) * kArmConstants.resistance / 12.0;
+
+    LOG(INFO) << "Battery current (Amps): " << battery_current.transpose();
+  }
+
+  ::Eigen::Matrix<double, 2, 4> last_K = ::Eigen::Matrix<double, 2, 4>::Zero();
+  for (int i = 0; i < 400; ++i) {
+    t.push_back(i * kDt);
+    x0.push_back(X(0));
+    x1.push_back(X(1));
+    x2.push_back(X(2));
+    x3.push_back(X(3));
+
+    const auto x_blocked = X.block<4, 1>(0, 0);
+
+    const ::Eigen::Matrix<double, 4, 4> final_A =
+        ::frc971::control_loops::NumericalJacobianX<4, 2>(
+            [dynamics](const auto &x_blocked, const auto &U, double kDt) {
+              return dynamics.UnboundedDiscreteDynamics(x_blocked, U, kDt);
+            },
+            x_blocked, U, 0.00505);
+    const ::Eigen::Matrix<double, 4, 2> final_B =
+        ::frc971::control_loops::NumericalJacobianU<4, 2>(
+            [dynamics](const auto &x_blocked, const auto &U, double kDt) {
+              return dynamics.UnboundedDiscreteDynamics(x_blocked, U, kDt);
+            },
+            x_blocked, U, 0.00505);
+
+    ::Eigen::Matrix<double, 2, 1> U_ff =
+        dynamics.FF_U(x_blocked, ::Eigen::Matrix<double, 2, 1>::Zero(),
+                      ::Eigen::Matrix<double, 2, 1>::Zero());
+
+    ::Eigen::Matrix<double, 4, 4> S;
+    ::Eigen::Matrix<double, 2, 4> K;
+    if (::frc971::controls::dlqr<4, 2>(final_A, final_B, Q, R, &K, &S) == 0) {
+      ::Eigen::EigenSolver<::Eigen::Matrix<double, 4, 4>> eigensolver(
+          final_A - final_B * K);
+
+      last_K = K;
+    } else {
+      LOG(INFO) << "Failed to solve for K at " << i;
+    }
+    U = U_ff + last_K * (goal - X);
+    if (std::abs(U(0)) > 12.0) {
+      U /= std::abs(U(0)) / 12.0;
+    }
+    if (std::abs(U(1)) > 12.0) {
+      U /= std::abs(U(1)) / 12.0;
+    }
+
+    const ::Eigen::Matrix<double, 2, 1> torque =
+        dynamics.TorqueFromCommand(X, U);
+    const ::Eigen::Matrix<double, 2, 1> current_per_motor =
+        dynamics.CurrentFromCommand(X, U);
+
+    current0.push_back(current_per_motor(0));
+    current1.push_back(current_per_motor(1));
+    torque0.push_back(torque(0));
+    torque1.push_back(torque(1));
+
+    u0.push_back(U(0));
+    u1.push_back(U(1));
+
+    X = dynamics.UnboundedDiscreteDynamics(X, U, kDt);
+  }
+
+  plotter.Title("Arm motion");
+  plotter.AddFigure("State");
+  plotter.AddLine(t, x0, "X 0");
+  plotter.AddLine(t, x1, "X 1");
+  plotter.AddLine(t, x2, "X 2");
+  plotter.AddLine(t, x3, "X 3");
+
+  plotter.AddLine(t, u0, "U 0");
+  plotter.AddLine(t, u1, "U 1");
+  plotter.Publish();
+
+  plotter.AddFigure("Command");
+  plotter.AddLine(t, u0, "U 0");
+  plotter.AddLine(t, u1, "U 1");
+
+  plotter.AddLine(t, current0, "current 0");
+  plotter.AddLine(t, current1, "current 1");
+  plotter.AddLine(t, torque0, "torque 0");
+  plotter.AddLine(t, torque1, "torque 1");
+  plotter.Publish();
+
+  plotter.Spin();
+
+  return 0;
+}
+
+}  // namespace arm
+}  // namespace superstructure
+}  // namespace control_loops
+}  // namespace y2023
+
+int main(int argc, char **argv) {
+  ::aos::InitGoogle(&argc, &argv);
+  return y2023::control_loops::superstructure::arm::Main();
+}