Package com.pathplanner.lib.controllers

Class PPLTVController

java.lang.Object

edu.wpi.first.math.controller.LTVUnicycleController

com.pathplanner.lib.controllers.PPLTVController

All Implemented Interfaces:

PathFollowingController

public class PPLTVController
extends LTVUnicycleController
implements PathFollowingController

LTV following controller

Constructor Summary

Constructors

Constructor	Description
PPLTVController(double dt)	Constructs a linear time-varying unicycle controller with default maximum desired error tolerances of (0.0625 m, 0.125 m, 2 rad) and default maximum desired control effort of (1 m/s, 2 rad/s).
PPLTVController(double dt, double maxVelocity)	Constructs a linear time-varying unicycle controller with default maximum desired error tolerances of (0.0625 m, 0.125 m, 2 rad) and default maximum desired control effort of (1 m/s, 2 rad/s).
PPLTVController(Vector<N3> qelems, Vector<N2> relems, double dt)	Constructs a linear time-varying unicycle controller.
PPLTVController(Vector<N3> qelems, Vector<N2> relems, double dt, double maxVelocity)	Constructs a linear time-varying unicycle controller.

Method Summary

Modifier and Type	Method	Description
ChassisSpeeds	calculateRobotRelativeSpeeds(Pose2d currentPose, PathPlannerTrajectoryState targetState)	Calculates the next output of the path following controller
boolean	isHolonomic()	Is this controller for holonomic drivetrains? Used to handle some differences in functionality in the path following command.
void	reset(Pose2d currentPose, ChassisSpeeds currentSpeeds)	Resets the controller based on the current state of the robot

Methods inherited from class edu.wpi.first.math.controller.LTVUnicycleController

atReference, calculate, calculate, setEnabled, setTolerance

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

PPLTVController

public PPLTVController(double dt)

Constructs a linear time-varying unicycle controller with default maximum desired error tolerances of (0.0625 m, 0.125 m, 2 rad) and default maximum desired control effort of (1 m/s, 2 rad/s).

Parameters:

dt - Discretization timestep in seconds.

PPLTVController

public PPLTVController(double dt,
 double maxVelocity)

Constructs a linear time-varying unicycle controller with default maximum desired error tolerances of (0.0625 m, 0.125 m, 2 rad) and default maximum desired control effort of (1 m/s, 2 rad/s).

Parameters:

dt - Discretization timestep in seconds.

maxVelocity - The maximum velocity in meters per second for the controller gain lookup table. The default is 9 m/s.

Throws:

IllegalArgumentException - if maxVelocity <= 0.

PPLTVController

public PPLTVController(Vector<N3> qelems,
 Vector<N2> relems,
 double dt)

Constructs a linear time-varying unicycle controller.

See https://docs.wpilib.org/en/stable/docs/software/advanced-controls/state-space/state-space-intro.html#lqr-tuning for how to select the tolerances.

Parameters:

qelems - The maximum desired error tolerance for each state.

relems - The maximum desired control effort for each input.

dt - Discretization timestep in seconds.

PPLTVController

public PPLTVController(Vector<N3> qelems,
 Vector<N2> relems,
 double dt,
 double maxVelocity)

Constructs a linear time-varying unicycle controller.

See https://docs.wpilib.org/en/stable/docs/software/advanced-controls/state-space/state-space-intro.html#lqr-tuning for how to select the tolerances.

Parameters:

qelems - The maximum desired error tolerance for each state.

relems - The maximum desired control effort for each input.

dt - Discretization timestep in seconds.

maxVelocity - The maximum velocity in meters per second for the controller gain lookup table. The default is 9 m/s.

Throws:

IllegalArgumentException - if maxVelocity <= 0 m/s or >= 15 m/s.

Method Details

calculateRobotRelativeSpeeds

public ChassisSpeeds calculateRobotRelativeSpeeds(Pose2d currentPose,
 PathPlannerTrajectoryState targetState)

Calculates the next output of the path following controller

Specified by:

calculateRobotRelativeSpeeds in interface PathFollowingController

Parameters:

currentPose - The current robot pose

targetState - The desired trajectory state

Returns:

The next robot relative output of the path following controller

reset

public void reset(Pose2d currentPose,
 ChassisSpeeds currentSpeeds)

Resets the controller based on the current state of the robot

Specified by:

reset in interface PathFollowingController

Parameters:

currentPose - Current robot pose

currentSpeeds - Current robot relative chassis speeds

isHolonomic

public boolean isHolonomic()

Is this controller for holonomic drivetrains? Used to handle some differences in functionality in the path following command.

Specified by:

isHolonomic in interface PathFollowingController

Returns:

True if this controller is for a holonomic drive train