Package xbot.common.subsystems.drive

Class PurePursuitCommand

java.lang.Object

edu.wpi.first.wpilibj2.command.Command

xbot.common.command.BaseCommand

xbot.common.subsystems.drive.PurePursuitCommand

All Implemented Interfaces:

Sendable, IPropertySupport

Direct Known Subclasses:

ConfigurablePurePursuitCommand

public abstract class PurePursuitCommand
extends BaseCommand

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static enum	PurePursuitCommand.PointLoadingMode
class	PurePursuitCommand.RabbitChaseInfo

Nested classes/interfaces inherited from class edu.wpi.first.wpilibj2.command.Command

Command.InterruptionBehavior

Field Summary

Fields

Modifier and Type	Field	Description
protected PurePursuitCommand.RabbitChaseInfo	chaseData
protected final BaseDriveSubsystem	drive
protected HeadingModule	headingModule
protected final DoubleProperty	perpindicularRatioProp
protected int	pointIndex
protected final BasePoseSubsystem	poseSystem
protected PIDManager	positionalPid
protected final DoubleProperty	rabbitLookAhead

Fields inherited from class xbot.common.command.BaseCommand

aKitLog, log, monitor, runningAlert

Constructor Summary

Constructors

Constructor	Description
PurePursuitCommand(HeadingModule.HeadingModuleFactory headingModuleFactory, BasePoseSubsystem pose, BaseDriveSubsystem drive, PropertyFactory propMan)	An implementation of Pure Pursuit for FRC.

Method Summary

Modifier and Type	Method	Description
void	end(boolean interrupted)
PurePursuitCommand.RabbitChaseInfo	evaluateCurrentPoint()	This is the core method that looks at the point list, figures out which point to be heading towards, and doing the math on how to get there.
PurePursuitCommand.RabbitChaseInfo	evaluateCurrentPoint(FieldPose robotPose)
void	execute()
double	getMotionBudget()
protected abstract List<RabbitPoint>	getOriginalPoints()
List<RabbitPoint>	getPlannedPointsToVisit()	If you want to see where this command is heading in the future (for visualization purposes, perhaps) you can get that information here.
protected abstract PurePursuitCommand.PointLoadingMode	getPursuitMode()
void	initialize()
boolean	isFinished()
void	setDotProductDrivingEnabled(boolean enabled)
void	setPIDs(HeadingModule headingModule, PIDManager positionalPid)	By default, the PurePursuitCommand uses the HeadingModule and PositionalPid from the DriveSubsystem.
void	setPIDsToDefault()

Methods inherited from class xbot.common.command.BaseCommand

getPrefix, includeOnSmartDashboard, includeOnSmartDashboard, requires, runsWhenDisabled, setRunsWhenDisabled

Methods inherited from class edu.wpi.first.wpilibj2.command.Command

addRequirements, addRequirements, alongWith, andThen, andThen, asProxy, beforeStarting, beforeStarting, cancel, deadlineFor, deadlineWith, finallyDo, finallyDo, getInterruptionBehavior, getName, getRequirements, getSubsystem, handleInterrupt, hasRequirement, ignoringDisable, initSendable, isScheduled, onlyIf, onlyWhile, raceWith, repeatedly, schedule, setName, setSubsystem, unless, until, withDeadline, withInterruptBehavior, withName, withTimeout, withTimeout

Methods inherited from class java.lang.Object

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

Field Details

poseSystem

protected final BasePoseSubsystem poseSystem

drive

protected final BaseDriveSubsystem drive

rabbitLookAhead

protected final DoubleProperty rabbitLookAhead

perpindicularRatioProp

protected final DoubleProperty perpindicularRatioProp

headingModule

protected HeadingModule headingModule

positionalPid

protected PIDManager positionalPid

pointIndex

protected int pointIndex

chaseData

protected PurePursuitCommand.RabbitChaseInfo chaseData

Constructor Details

PurePursuitCommand

public PurePursuitCommand(HeadingModule.HeadingModuleFactory headingModuleFactory,
 BasePoseSubsystem pose,
 BaseDriveSubsystem drive,
 PropertyFactory propMan)

An implementation of Pure Pursuit for FRC. We got the basic idea from here: http://www8.cs.umu.se/kurser/TDBD17/VT06/utdelat/Assignment%20Papers/Path%20Tracking%20for%20a%20Miniature%20Robot.pdf Fundamentally, you can add field points to this command (x,y, and rotation) and the robot will attempt to reach all those points with a smooth path. This works for any drive base, but presumably, holonomic robots can solve this problem more effectively. You will see references to rabbits, or "chasing the rabbit". This is alluding to how greyhoud races use mechanical rabbits, which is designed to always stay ahead of them, regardless of their speed. This is similiar to how, as the robot uses pure pursuit, it is always chasing a point it can never reach.

Parameters:

headingModuleFactory - HeadingModuleFactory

pose - BasePoseSubsystem

drive - BaseDriveSubsystem

propMan - PropertyManager

Method Details

setPIDs

public void setPIDs(HeadingModule headingModule,
 PIDManager positionalPid)

By default, the PurePursuitCommand uses the HeadingModule and PositionalPid from the DriveSubsystem. However, if you want to change the PIDs used on the fly, you can here.

Parameters:

headingModule - Used for rotation

positionalPid - Used for translation

setPIDsToDefault

public void setPIDsToDefault()

setDotProductDrivingEnabled

public void setDotProductDrivingEnabled(boolean enabled)

getOriginalPoints

protected abstract List<RabbitPoint> getOriginalPoints()

getPursuitMode

protected abstract PurePursuitCommand.PointLoadingMode getPursuitMode()

getPlannedPointsToVisit

public List<RabbitPoint> getPlannedPointsToVisit()

If you want to see where this command is heading in the future (for visualization purposes, perhaps) you can get that information here.

Returns:

List of points to visit

initialize

public void initialize()

Overrides:

initialize in class BaseCommand

execute

public void execute()

Overrides:

execute in class Command

evaluateCurrentPoint

public PurePursuitCommand.RabbitChaseInfo evaluateCurrentPoint(FieldPose robotPose)

evaluateCurrentPoint

public PurePursuitCommand.RabbitChaseInfo evaluateCurrentPoint()

This is the core method that looks at the point list, figures out which point to be heading towards, and doing the math on how to get there.

Returns:

Information about what the robot would like to do in order to reach its points.

end

public void end(boolean interrupted)

Overrides:

end in class BaseCommand

isFinished

public boolean isFinished()

Overrides:

isFinished in class Command

getMotionBudget

public double getMotionBudget()