Add feedforward components (#2045)

Add helper classes for computing feedforwards with parameters supplied by the characterization tool.
This commit is contained in:
Oblarg
2019-11-09 23:16:42 -05:00
committed by Peter Johnson
parent 5f33d6af12
commit 7dc7c71b58
13 changed files with 457 additions and 63 deletions

View File

@@ -14,6 +14,7 @@ import java.util.function.Supplier;
import edu.wpi.first.wpilibj.Timer;
import edu.wpi.first.wpilibj.controller.PIDController;
import edu.wpi.first.wpilibj.controller.RamseteController;
import edu.wpi.first.wpilibj.controller.SimpleMotorFeedforward;
import edu.wpi.first.wpilibj.geometry.Pose2d;
import edu.wpi.first.wpilibj.kinematics.ChassisSpeeds;
import edu.wpi.first.wpilibj.kinematics.DifferentialDriveKinematics;
@@ -45,9 +46,7 @@ public class RamseteCommand extends CommandBase {
private final Trajectory m_trajectory;
private final Supplier<Pose2d> m_pose;
private final RamseteController m_follower;
private final double m_ks;
private final double m_kv;
private final double m_ka;
private final SimpleMotorFeedforward m_feedforward;
private final DifferentialDriveKinematics m_kinematics;
private final DoubleSupplier m_leftSpeed;
private final DoubleSupplier m_rightSpeed;
@@ -67,12 +66,8 @@ public class RamseteCommand extends CommandBase {
* @param trajectory The trajectory to follow.
* @param pose A function that supplies the robot pose - use one of
* the odometry classes to provide this.
* @param controller The RAMSETE controller used to follow the trajectory.
* @param ksVolts Constant feedforward term for the robot drive.
* @param kvVoltSecondsPerMeter Velocity-proportional feedforward term for the robot
* drive.
* @param kaVoltSecondsSquaredPerMeter Acceleration-proportional feedforward term for the robot
* drive.
* @param controller The RAMSETE controller used to follow the trajectory.
* @param feedforward The feedforward to use for the drive.
* @param kinematics The kinematics for the robot drivetrain.
* @param leftWheelSpeedMetersPerSecond A function that supplies the speed of the left side of
* the robot drive.
@@ -88,9 +83,7 @@ public class RamseteCommand extends CommandBase {
public RamseteCommand(Trajectory trajectory,
Supplier<Pose2d> pose,
RamseteController controller,
double ksVolts,
double kvVoltSecondsPerMeter,
double kaVoltSecondsSquaredPerMeter,
SimpleMotorFeedforward feedforward,
DifferentialDriveKinematics kinematics,
DoubleSupplier leftWheelSpeedMetersPerSecond,
DoubleSupplier rightWheelSpeedMetersPerSecond,
@@ -101,9 +94,7 @@ public class RamseteCommand extends CommandBase {
m_trajectory = requireNonNullParam(trajectory, "trajectory", "RamseteCommand");
m_pose = requireNonNullParam(pose, "pose", "RamseteCommand");
m_follower = requireNonNullParam(controller, "controller", "RamseteCommand");
m_ks = ksVolts;
m_kv = kvVoltSecondsPerMeter;
m_ka = kaVoltSecondsSquaredPerMeter;
m_feedforward = feedforward;
m_kinematics = requireNonNullParam(kinematics, "kinematics", "RamseteCommand");
m_leftSpeed = requireNonNullParam(leftWheelSpeedMetersPerSecond,
"leftWheelSpeedMetersPerSecond",
@@ -146,9 +137,7 @@ public class RamseteCommand extends CommandBase {
m_kinematics = requireNonNullParam(kinematics, "kinematics", "RamseteCommand");
m_output = requireNonNullParam(outputMetersPerSecond, "output", "RamseteCommand");
m_ks = 0;
m_kv = 0;
m_ka = 0;
m_feedforward = null;
m_leftSpeed = null;
m_rightSpeed = null;
m_leftController = null;
@@ -192,14 +181,12 @@ public class RamseteCommand extends CommandBase {
if (m_usePID) {
double leftFeedforward =
m_ks * Math.signum(leftSpeedSetpoint)
+ m_kv * leftSpeedSetpoint
+ m_ka * (leftSpeedSetpoint - m_prevSpeeds.leftMetersPerSecond) / dt;
m_feedforward.calculate(leftSpeedSetpoint,
(leftSpeedSetpoint - m_prevSpeeds.leftMetersPerSecond) / dt);
double rightFeedforward =
m_ks * Math.signum(rightSpeedSetpoint)
+ m_kv * rightSpeedSetpoint
+ m_ka * (rightSpeedSetpoint - m_prevSpeeds.rightMetersPerSecond) / dt;
m_feedforward.calculate(rightSpeedSetpoint,
(rightSpeedSetpoint - m_prevSpeeds.rightMetersPerSecond) / dt);
leftOutput = leftFeedforward
+ m_leftController.calculate(m_leftSpeed.getAsDouble(),