kinematics::SwerveDriveKinematics Class Reference

Calculates forward and inverse drivebase kinematics for a 4-wheel swerve drivebase with specifiable width and length. More...

#include <SwerveDriveKinematics.h>

Public Member Functions
	SwerveDriveKinematics (double baseWidth, double baseLength)
	Create a new SwerveDriveKinematics with the given wheel base width and length from rear of robot.
swervewheelvel_t	robotVelToWheelVel (double xVel, double yVel, double thetaVel) const
	Given the robot's translational and angular velocity in the robot's reference frame, find the speeds and angles of the robot's wheels in the robot's reference frame.
navtypes::pose_t	wheelVelToRobotVel (swervewheelvel_t wheelVel) const
	Given the speeds and angles of the robot's wheels in the robot's reference frame, find the robot's translational velocity and angular velocity in the robot's reference frame.
navtypes::pose_t	getLocalPoseUpdate (const swervewheelvel_t &wheelVel, double dt) const
	Calculate the pose update in the local reference frame given the velocities of the robot's wheels and the time step.
navtypes::pose_t	getPoseUpdate (const swervewheelvel_t &wheelVel, double heading, double dt) const
	Calculate the pose update in the global reference frame given the velocities of the robot's wheels and the time step.
navtypes::pose_t	getNextPose (const swervewheelvel_t &wheelVel, const navtypes::pose_t &pose, double dt) const
	Calculate the next pose of the robot in the global reference frame.

Detailed Description

Calculates forward and inverse drivebase kinematics for a 4-wheel swerve drivebase with specifiable width and length.

Constructor & Destructor Documentation

SwerveDriveKinematics()

kinematics::SwerveDriveKinematics::SwerveDriveKinematics ( double baseWidth, double baseLength )

explicit

Create a new SwerveDriveKinematics with the given wheel base width and length from rear of robot.

Parameters

baseWidth	The width of the wheelbase. The units themselves don't matter, as long as you're consistent.
baseLength	The length of the wheelbase. The units themselves don't matter, as long as you're consistent.

Member Function Documentation

getLocalPoseUpdate()

pose_t kinematics::SwerveDriveKinematics::getLocalPoseUpdate	(	const swervewheelvel_t &	wheelVel,
		double	dt ) const

Calculate the pose update in the local reference frame given the velocities of the robot's wheels and the time step.

Parameters

wheelVel	The velocities of the wheels.
dt	The elapsed time in seconds for which the update is calculated. The robot has been moving at the specified velocity for this much time.

Returns

The pose update in the robot's local reference frame.

getNextPose()

pose_t kinematics::SwerveDriveKinematics::getNextPose	(	const swervewheelvel_t &	wheelVel,
		const navtypes::pose_t &	pose,
		double	dt ) const

Calculate the next pose of the robot in the global reference frame.

(map space)

Parameters

wheelVel	The velocities of the wheels.
pose	The current pose of the robot, in the global reference frame.
dt	The elapsed time in seconds for which the update is calculated. The robot has been moving at the specified velocity for this much time.

Returns

The next pose of the robot in the global reference frame after having moved at the specified velocity for the specified time.

getPoseUpdate()

pose_t kinematics::SwerveDriveKinematics::getPoseUpdate	(	const swervewheelvel_t &	wheelVel,
		double	heading,
		double	dt ) const

Calculate the pose update in the global reference frame given the velocities of the robot's wheels and the time step.

Parameters

wheelVel	The velocities of the wheels.
heading	The heading of the robot, in radians.
dt	The elapsed time in seconds for which the update is calculated. The robot has been moving at the specified velocity for this much time.

Returns

The pose update in the global reference frame.

robotVelToWheelVel()

swervewheelvel_t kinematics::SwerveDriveKinematics::robotVelToWheelVel	(	double	xVel,
		double	yVel,
		double	thetaVel ) const

Given the robot's translational and angular velocity in the robot's reference frame, find the speeds and angles of the robot's wheels in the robot's reference frame.

Parameters

xVel	the forward velocity component of the robot, in the robot's reference frame. (positive = front)
yVel	the left/right velocity component of the robot, in the robot's reference frame. (positive = left)
thetaVel	the angular velocity of the robot in the robot's reference frame, in rad/sec. (positive = CCW)

Returns

the speeds and angles of the robot's wheels in the robot's reference frame.

wheelVelToRobotVel()

pose_t kinematics::SwerveDriveKinematics::wheelVelToRobotVel

(

swervewheelvel_t

wheelVel

)

const

Given the speeds and angles of the robot's wheels in the robot's reference frame, find the robot's translational velocity and angular velocity in the robot's reference frame.

Parameters

wheelVel

the struct containing the speeds and angles of the robot's wheels in the robot's reference frame.

Returns

the robot's translational and angular velocity in the robot's reference frame.

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

• src/kinematics/SwerveDriveKinematics.h
• src/kinematics/SwerveDriveKinematics.cpp