A class for driving Mecanum drive platforms. More...

#include <frc/drive/MecanumDrive.h>

Inheritance diagram for frc::MecanumDrive:

Classes
struct	WheelSpeeds
	Wheel speeds for a mecanum drive. More...

Public Member Functions
	MecanumDrive (MotorController &frontLeftMotor, MotorController &rearLeftMotor, MotorController &frontRightMotor, MotorController &rearRightMotor)
	Construct a MecanumDrive. More...

	~MecanumDrive () override=default

	MecanumDrive (MecanumDrive &&)=default

MecanumDrive &	operator= (MecanumDrive &&)=default

void	DriveCartesian (double xSpeed, double ySpeed, double zRotation, Rotation2d gyroAngle=0_rad)
	Drive method for Mecanum platform. More...

void	DrivePolar (double magnitude, Rotation2d angle, double zRotation)
	Drive method for Mecanum platform. More...

void	StopMotor () override

std::string	GetDescription () const override
	The return value from this method is printed out when an error occurs. More...

void	InitSendable (wpi::SendableBuilder &builder) override
	Initializes this Sendable object. More...

Public Member Functions inherited from frc::RobotDriveBase
	RobotDriveBase ()

	~RobotDriveBase () override=default

	RobotDriveBase (RobotDriveBase &&)=default

RobotDriveBase &	operator= (RobotDriveBase &&)=default

void	SetDeadband (double deadband)
	Sets the deadband applied to the drive inputs (e.g., joystick values). More...

void	SetMaxOutput (double maxOutput)
	Configure the scaling factor for using RobotDrive with motor controllers in a mode other than PercentVbus or to limit the maximum output. More...

void	FeedWatchdog ()
	Feed the motor safety object. More...

void	StopMotor () override=0

std::string	GetDescription () const override=0
	The return value from this method is printed out when an error occurs. More...

Public Member Functions inherited from frc::MotorSafety
	MotorSafety ()

virtual	~MotorSafety ()

	MotorSafety (MotorSafety &&rhs)

MotorSafety &	operator= (MotorSafety &&rhs)

void	Feed ()
	Feed the motor safety object. More...

void	SetExpiration (units::second_t expirationTime)
	Set the expiration time for the corresponding motor safety object. More...

units::second_t	GetExpiration () const
	Retrieve the timeout value for the corresponding motor safety object. More...

bool	IsAlive () const
	Determine if the motor is still operating or has timed out. More...

void	SetSafetyEnabled (bool enabled)
	Enable/disable motor safety for this device. More...

bool	IsSafetyEnabled () const
	Return the state of the motor safety enabled flag. More...

void	Check ()
	Check if this motor has exceeded its timeout. More...

virtual void	StopMotor ()=0

virtual std::string	GetDescription () const =0
	The return value from this method is printed out when an error occurs. More...

Public Member Functions inherited from wpi::Sendable
virtual	~Sendable ()=default

virtual void	InitSendable (SendableBuilder &builder)=0
	Initializes this Sendable object. More...

Public Member Functions inherited from wpi::SendableHelper< MecanumDrive >
	SendableHelper (const SendableHelper &rhs)=default

	SendableHelper (SendableHelper &&rhs)

SendableHelper &	operator= (const SendableHelper &rhs)=default

SendableHelper &	operator= (SendableHelper &&rhs)

Static Public Member Functions
static WheelSpeeds	DriveCartesianIK (double xSpeed, double ySpeed, double zRotation, Rotation2d gyroAngle=0_rad)
	Cartesian inverse kinematics for Mecanum platform. More...

Static Public Member Functions inherited from frc::MotorSafety
static void	CheckMotors ()
	Check the motors to see if any have timed out. More...

Additional Inherited Members
Public Types inherited from frc::RobotDriveBase
enum	MotorType { kFrontLeft = 0 , kFrontRight = 1 , kRearLeft = 2 , kRearRight = 3 , kLeft = 0 , kRight = 1 , kBack = 2 }
	The location of a motor on the robot for the purpose of driving. More...

Protected Member Functions inherited from wpi::SendableHelper< MecanumDrive >
	SendableHelper ()=default

	~SendableHelper ()

Static Protected Member Functions inherited from frc::RobotDriveBase
static void	Desaturate (std::span< double > wheelSpeeds)
	Renormalize all wheel speeds if the magnitude of any wheel is greater than 1.0. More...

Protected Attributes inherited from frc::RobotDriveBase
double	m_deadband = 0.02

double	m_maxOutput = 1.0

Detailed Description

A class for driving Mecanum drive platforms.

Mecanum drives are rectangular with one wheel on each corner. Each wheel has rollers toed in 45 degrees toward the front or back. When looking at the wheels from the top, the roller axles should form an X across the robot.

Drive base diagram:

\_______/
\ |   | /
  |   |
/_|___|_\
/       \

Each Drive() function provides different inverse kinematic relations for a Mecanum drive robot.

This library uses the NWU axes convention (North-West-Up as external reference in the world frame). The positive X axis points ahead, the positive Y axis points to the left, and the positive Z axis points up. Rotations follow the right-hand rule, so counterclockwise rotation around the Z axis is positive.

Note: the axis conventions used in this class differ from DifferentialDrive. This may change in a future year's WPILib release.

Inputs smaller then 0.02 will be set to 0, and larger values will be scaled so that the full range is still used. This deadband value can be changed with SetDeadband().

MotorSafety is enabled by default. The DriveCartesian or DrivePolar methods should be called periodically to avoid Motor Safety timeouts.

Constructor & Destructor Documentation

◆ MecanumDrive() [1/2]

frc::MecanumDrive::MecanumDrive	(	MotorController &	frontLeftMotor,
		MotorController &	rearLeftMotor,
		MotorController &	frontRightMotor,
		MotorController &	rearRightMotor
	)

Construct a MecanumDrive.

If a motor needs to be inverted, do so before passing it in.

◆ ~MecanumDrive()

frc::MecanumDrive::~MecanumDrive ( )

overridedefault

◆ MecanumDrive() [2/2]

frc::MecanumDrive::MecanumDrive ( MecanumDrive && )

default

Member Function Documentation

◆ DriveCartesian()

void frc::MecanumDrive::DriveCartesian	(	double	xSpeed,
		double	ySpeed,
		double	zRotation,
		Rotation2d	gyroAngle = `0_rad`
	)

Drive method for Mecanum platform.

Angles are measured counterclockwise from the positive X axis. The robot's speed is independent from its angle or rotation rate.

Parameters

xSpeed	The robot's speed along the X axis [-1.0..1.0]. Forward is positive.
ySpeed	The robot's speed along the Y axis [-1.0..1.0]. Left is positive.
zRotation	The robot's rotation rate around the Z axis [-1.0..1.0]. Counterclockwise is positive.
gyroAngle	The gyro heading around the Z axis. Use this to implement field-oriented controls.

◆ DriveCartesianIK()

static WheelSpeeds frc::MecanumDrive::DriveCartesianIK	(	double	xSpeed,
		double	ySpeed,
		double	zRotation,
		Rotation2d	gyroAngle = `0_rad`
	)

static

Cartesian inverse kinematics for Mecanum platform.

Angles are measured counterclockwise from the positive X axis. The robot's speed is independent from its angle or rotation rate.

Parameters

xSpeed	The robot's speed along the X axis [-1.0..1.0]. Forward is positive.
ySpeed	The robot's speed along the Y axis [-1.0..1.0]. Left is positive.
zRotation	The robot's rotation rate around the Z axis [-1.0..1.0]. Counterclockwise is positive.
gyroAngle	The gyro heading around the Z axis. Use this to implement field-oriented controls.

Returns: Wheel speeds [-1.0..1.0].

◆ DrivePolar()

void frc::MecanumDrive::DrivePolar	(	double	magnitude,
		Rotation2d	angle,
		double	zRotation
	)

Drive method for Mecanum platform.

Angles are measured counterclockwise from the positive X axis. The robot's speed is independent from its angle or rotation rate.

Parameters

magnitude	The robot's speed at a given angle [-1.0..1.0]. Forward is positive.
angle	The angle around the Z axis at which the robot drives.
zRotation	The robot's rotation rate around the Z axis [-1.0..1.0]. Counterclockwise is positive.

◆ GetDescription()

std::string frc::MecanumDrive::GetDescription ( ) const

overridevirtual

The return value from this method is printed out when an error occurs.

This method must not throw!

Implements frc::RobotDriveBase.

◆ InitSendable()

void frc::MecanumDrive::InitSendable ( wpi::SendableBuilder & builder )

overridevirtual

Initializes this Sendable object.

Parameters

builder sendable builder

Implements wpi::Sendable.

◆ operator=()

MecanumDrive & frc::MecanumDrive::operator= ( MecanumDrive && )

default

◆ StopMotor()

void frc::MecanumDrive::StopMotor ( )

overridevirtual

Implements frc::RobotDriveBase.

The documentation for this class was generated from the following file:

frc/drive/MecanumDrive.h

Classes

Public Member Functions

Static Public Member Functions

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ MecanumDrive() [1/2]

◆ ~MecanumDrive()

◆ MecanumDrive() [2/2]

Member Function Documentation

◆ DriveCartesian()

◆ DriveCartesianIK()

◆ DrivePolar()

◆ GetDescription()

◆ InitSendable()

◆ operator=()

◆ StopMotor()