The ForwardKinematics class simulates kinematic behavoir of a car like mobile platform given its current control parameters (e.g. steering, speed etc.) More...

#include <ForwardKinematics.h>

Public Member Functions
std::pair< double, double >	calcICC (double alpha)
	Calculates the current instantaneous center of curvature given a steering angle. More...

double	calcRadius (std::pair< double, double > ICC)
	Calculate the radius of the current robot tracjectory around the instantaneous center of curvature (ICC). More...

Eigen::Matrix4d *	calcRot (double theta, double alpha)
	Calculate the current rotation matrix. More...

double	calcTheta (double distance, double radius)
	Calculate the current orientation of the robot with respect to the coordinate system of the previous update. More...

Eigen::Matrix4d *	calcTrans (double radius, double distance, double alpha, std::pair< double, double > ICC)
	Calculate the current translation matrix. More...

double	degToRad (double angle)
	Conversion from degrees to radiants. More...

double	flattenZeros (double value)
	Rounds values close to zero to exactly zero. More...

	ForwardKinematics ()
	ForwardKinematics default constructor. More...

	ForwardKinematics (const ForwardKinematics &other)
	ForwardKinematics default copy constructor. More...

	ForwardKinematics (double k, std::vector< double > initialPose=std::vector< double >(3, 0))
	ForwardKinematics constructor. More...

const double	getRadius () const
	Get the radius of the current robot tracjectory around the instantaneous center of curvature (ICC). More...

std::vector< double > &	getUpdate (double alpha, double distance)
	Get the current position and orientation. More...

double	radToDeg (double angle)
	Conversion from radiants to degrees. More...

Public Attributes
double	PI

Private Member Functions
void	init ()
	Initialize simulation. More...

Private Attributes
std::vector< double >	currentPosition

Eigen::Matrix4d	initT

double	k

Eigen::Matrix4d	prevT

double	radius

std::vector< Eigen::Matrix4d >	T

Detailed Description

The ForwardKinematics class simulates kinematic behavoir of a car like mobile platform given its current control parameters (e.g. steering, speed etc.)

This is not physically accurate simulation of forces, torque and accelerations. Its mainly used to demonstrate kinematic behaviour of car like robot in an ideal environment, i.e. infinite acceleration, zero steering lag and perfect tire grip.

Definition at line 28 of file ForwardKinematics.h.

Constructor & Destructor Documentation

ForwardKinematics::ForwardKinematics ( )

ForwardKinematics default constructor.

Definition at line 9 of file ForwardKinematics.cpp.

ForwardKinematics::ForwardKinematics ( const ForwardKinematics & other )

ForwardKinematics default copy constructor.

Definition at line 10 of file ForwardKinematics.cpp.

ForwardKinematics::ForwardKinematics	(	double	k,
		std::vector< double >	initialPose = `std::vector<double>(3, 0)`
	)

ForwardKinematics constructor.

Parameters

[in]	k	wheel base of the mobile robot in meters.
[in]	initialPose	initial pose of the robot. (0: - y-coordinate, 1: x-coordinate, 2: yaw in radiants)

Definition at line 21 of file ForwardKinematics.cpp.

Member Function Documentation

std::pair< double, double > ForwardKinematics::calcICC ( double alpha )

Calculates the current instantaneous center of curvature given a steering angle.

Parameters

[in] alpha current steering angle

Returns: pair of coordinates of the ICC (first: x, second: y)

Definition at line 52 of file ForwardKinematics.cpp.

double ForwardKinematics::calcRadius ( std::pair< double, double > ICC )

Calculate the radius of the current robot tracjectory around the instantaneous center of curvature (ICC).

Parameters

[in] ICC pair of coordinates of the ICC (first: x, second: y)

Returns: radius in meters

Definition at line 65 of file ForwardKinematics.cpp.

Eigen::Matrix4d * ForwardKinematics::calcRot	(	double	theta,
		double	alpha
	)

Calculate the current rotation matrix.

Parameters

[in]	theta	orientation of the previous update
[in]	alpha	current steering angle

Returns: current rotation matrix

Definition at line 74 of file ForwardKinematics.cpp.

double ForwardKinematics::calcTheta	(	double	distance,
		double	radius
	)

Calculate the current orientation of the robot with respect to the coordinate system of the previous update.

Parameters

[in]	distance	distance travelled between updates
[in]	radius	radius with respect to the ICC in meters

Returns: current orientation in radiants

Definition at line 70 of file ForwardKinematics.cpp.

Eigen::Matrix4d * ForwardKinematics::calcTrans	(	double	radius,
		double	distance,
		double	alpha,
		std::pair< double, double >	ICC
	)

Calculate the current translation matrix.

Parameters

[in]	alpha	current steering angle
[in]	distance	distance travelled between updates
[in]	radius	radius with respect to the ICC in meters
[in]	ICC	pair of coordinates of the ICC (first: x, second: y)

Returns: current translation matrix

Definition at line 96 of file ForwardKinematics.cpp.

double ForwardKinematics::degToRad ( double angle )

Conversion from degrees to radiants.

Parameters

[in] angle angle in degrees

Returns: angle in radiants

Definition at line 62 of file ForwardKinematics.cpp.

double ForwardKinematics::flattenZeros ( double value )

Rounds values close to zero to exactly zero.

Returns: 0 if value > epsilon, else value.

Definition at line 58 of file ForwardKinematics.cpp.

const double ForwardKinematics::getRadius ( ) const

Get the radius of the current robot tracjectory around the instantaneous center of curvature (ICC).

Returns: radius in meters

Definition at line 50 of file ForwardKinematics.cpp.

std::vector< double > & ForwardKinematics::getUpdate	(	double	alpha,
		double	distance
	)

Get the current position and orientation.

Parameters

[in]	alpha	current steering angle
[in]	distance	distance travelled between updates

Returns: current Current pose (0: - y-coordinate, 1: x-coordinate, 2: yaw in radiants)

Definition at line 135 of file ForwardKinematics.cpp.

void ForwardKinematics::init ( )

private

Initialize simulation.

Definition at line 23 of file ForwardKinematics.cpp.

double ForwardKinematics::radToDeg ( double angle )

Conversion from radiants to degrees.

Parameters

[in] angle angle in radiants

Returns: angle in degrees

Definition at line 63 of file ForwardKinematics.cpp.

Member Data Documentation

std::vector<double> ForwardKinematics::currentPosition

private

current Current pose (0: - y-coordinate, 1: x-coordinate, 2: yaw in radiants)

Definition at line 118 of file ForwardKinematics.h.

Eigen::Matrix4d ForwardKinematics::initT

private

Initial forward kinematic transformation matrix

Definition at line 115 of file ForwardKinematics.h.

double ForwardKinematics::k

private

Wheelbase in meters

Definition at line 113 of file ForwardKinematics.h.

double ForwardKinematics::PI

pi

Definition at line 110 of file ForwardKinematics.h.

Eigen::Matrix4d ForwardKinematics::prevT

private

Previous kinematic transformation matrix

Definition at line 117 of file ForwardKinematics.h.

double ForwardKinematics::radius

private

Radius of the current robot tracjectory around the instantaneous center of curvature (ICC)

Definition at line 114 of file ForwardKinematics.h.

std::vector<Eigen::Matrix4d> ForwardKinematics::T

private

History of kinematic transformation matrices

Definition at line 116 of file ForwardKinematics.h.

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

Public Member Functions

Public Attributes

Private Member Functions

Private Attributes

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation