Add ProfiledPIDSubsystem example (#2076)

wpilibcExamples/src/main/cpp/examples/ArmBot/include/Constants.h

@@ -0,0 +1,71 @@
+/*----------------------------------------------------------------------------*/
+/* Copyright (c) 2019 FIRST. All Rights Reserved.                             */
+/* Open Source Software - may be modified and shared by FRC teams. The code   */
+/* must be accompanied by the FIRST BSD license file in the root directory of */
+/* the project.                                                               */
+/*----------------------------------------------------------------------------*/
+
+#pragma once
+
+#include <units/units.h>
+#include <wpi/math>
+
+/**
+ * The Constants header provides a convenient place for teams to hold robot-wide
+ * numerical or bool constants.  This should not be used for any other purpose.
+ *
+ * It is generally a good idea to place constants into subsystem- or
+ * command-specific namespaces within this header, which can then be used where
+ * they are needed.
+ */
+
+namespace DriveConstants {
+constexpr int kLeftMotor1Port = 0;
+constexpr int kLeftMotor2Port = 1;
+constexpr int kRightMotor1Port = 2;
+constexpr int kRightMotor2Port = 3;
+
+constexpr int kLeftEncoderPorts[]{0, 1};
+constexpr int kRightEncoderPorts[]{2, 3};
+constexpr bool kLeftEncoderReversed = false;
+constexpr bool kRightEncoderReversed = true;
+
+constexpr int kEncoderCPR = 1024;
+constexpr double kWheelDiameterInches = 6;
+constexpr double kEncoderDistancePerPulse =
+    // Assumes the encoders are directly mounted on the wheel shafts
+    (kWheelDiameterInches * wpi::math::pi) / static_cast<double>(kEncoderCPR);
+}  // namespace DriveConstants
+
+namespace ArmConstants {
+constexpr int kMotorPort = 4;
+
+constexpr double kP = 1;
+
+// These are fake gains; in actuality these must be determined individually for
+// each robot
+constexpr auto kS = 1_V;
+constexpr auto kCos = 1_V;
+constexpr auto kV = 0.5_V * 1_s / 1_rad;
+constexpr auto kA = 0.1_V * 1_s * 1_s / 1_rad;
+
+constexpr auto kMaxVelocity = 3_rad_per_s;
+constexpr auto kMaxAcceleration = 10_rad / (1_s * 1_s);
+
+constexpr int kEncoderPorts[]{4, 5};
+constexpr int kEncoderPPR = 256;
+constexpr auto kEncoderDistancePerPulse = 2.0_rad * wpi::math::pi / kEncoderPPR;
+
+// The offset of the arm from the horizontal in its neutral position,
+// measured from the horizontal
+constexpr auto kArmOffset = 0.5_rad;
+}  // namespace ArmConstants
+
+namespace AutoConstants {
+constexpr auto kAutoTimeoutSeconds = 12_s;
+constexpr auto kAutoShootTimeSeconds = 7_s;
+}  // namespace AutoConstants
+
+namespace OIConstants {
+constexpr int kDriverControllerPort = 1;
+}  // namespace OIConstants