The CarModel class simulates kinematic behavoir of a car like mobile platform, by using the ForwardKinematics library. More...

#include "pses_simulation/CarModel.h"

Public Member Functions
	CarModel (const double dAxis, const ros::Time &time, std::vector< double > initialPose=std::vector< double >(3, 0), const double vMax=2.0, const double angleMax=22.5, const double speedMax=20, const double steeringMax=50)
	CarModel constructor. More...

const double	getAngularVelocity () const
	Get current angular velocity of the mobile plattform. More...

const double	getAx () const
	Get current acceleration in x direction of the mobile plattform relative to the robot coordinate system. More...

const double	getAy () const
	Get current acceleration in y direction of the mobile plattform relative to the robot coordinate system. More...

const double	getDistance () const
	Get total travelled distance of the mobile plattform. More...

const int	getSteering () const
	Get current steering level of the mobile plattform. More...

const double	getSteeringAngle () const
	Get current steering angle of the mobile plattform. More...

const double	getTimeStep () const
	Get current time step. More...

const pose_ptr	getUpdate (const int newSteering, const int newSpeed, const ros::Time &time)
	Update the simulation with current control settings and time. More...

const pose_ptr	getUpdateTwist (const twist_msg cmd_vel, const ros::Time &time)
	Update the simulation with current motion parameters and time. More...

const double	getVelocity () const
	Get current velocity of the mobile plattform. More...

const double	getVx () const
	Get current velocity in x direction of the mobile plattform relative to the global coordinate system. More...

const double	getVy () const
	Get current velocity in y direction of the mobile plattform relative to the global coordinate system. More...

Private Member Functions
void	angleToSteering (const double alpha)
	Conversion from given steering angle to current steering level based on a lookup table. More...

void	setAccelerationComponents (const double prevV)
	Calculate and set current acceleration components in x and y direction. More...

void	setAngularVelocity (const double oldYaw)
	Calculate and set angular velocity by providing the orientation of the previous time step. More...

void	setSteering (const int steering)
	Set current steering level. More...

void	setVelocity (const double newVel)
	Set current velocity. More...

void	setVelocityComponents ()
	Calculate and set current velocity components in x and y direction. More...

void	speedToVelocity (const int speed)
	Conversion from given motor level to current velocity based on a lookup table. More...

void	steeringToAngle ()
	Conversion from current steering level to steering angle based on a lookup table. More...

Private Attributes
double	a_x

double	a_y

double	angleMax

double	angularVelocity

double	distance

ForwardKinematics	fwdKin

ros::Time	lastUpdate

std::vector< double >	pose

double	speedMax

int	steering

double	steeringAngle

double	steeringMax

double	timeStep

double	v_x

double	v_y

double	velocity

double	vMax

Detailed Description

The CarModel class simulates kinematic behavoir of a car like mobile platform, by using the ForwardKinematics library.

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 39 of file CarModel.h.

Constructor & Destructor Documentation

CarModel::CarModel	(	const double	dAxis,
		const ros::Time &	time,
		std::vector< double >	initialPose = `std::vector<double>(3, 0)`,
		const double	vMax = `2.0`,
		const double	angleMax = `22.5`,
		const double	speedMax = `20`,
		const double	steeringMax = `50`
	)

CarModel constructor.

Parameters

[in]	dAxis	wheel base of the mobile robot in meters.
[in]	time	current Ros::Time.
[in]	initialPose	initial pose of the robot. (0: - y-coordinate, 1: x-coordinate, 2: yaw in radiants).
[in]	vMax	maximum speed of the mobile robot in meters/second.
[in]	angleMax	maximum steering angle of the mobile robot in degrees.
[in]	speedMax	maximum motor level of the mobile robot.
[in]	steeringMax	maximum steering level of the mobile robot.

Definition at line 9 of file CarModel.cpp.

Member Function Documentation

void CarModel::angleToSteering ( const double alpha )

private

Conversion from given steering angle to current steering level based on a lookup table.

Parameters

[in] alpha steering angle in degrees

Definition at line 80 of file CarModel.cpp.

const double CarModel::getAngularVelocity ( ) const

Get current angular velocity of the mobile plattform.

Returns: current angular velocity

Definition at line 73 of file CarModel.cpp.

const double CarModel::getAx ( ) const

Get current acceleration in x direction of the mobile plattform relative to the robot coordinate system.

Returns: current acceleration in x direction

Definition at line 77 of file CarModel.cpp.

const double CarModel::getAy ( ) const

Get current acceleration in y direction of the mobile plattform relative to the robot coordinate system.

Returns: current acceleration in y direction

Definition at line 78 of file CarModel.cpp.

const double CarModel::getDistance ( ) const

Get total travelled distance of the mobile plattform.

Returns: total travelled distance

Definition at line 66 of file CarModel.cpp.

const int CarModel::getSteering ( ) const

Get current steering level of the mobile plattform.

Returns: current steering level

Definition at line 70 of file CarModel.cpp.

const double CarModel::getSteeringAngle ( ) const

Get current steering angle of the mobile plattform.

Returns: current steering angle

Definition at line 71 of file CarModel.cpp.

const double CarModel::getTimeStep ( ) const

Get current time step.

Returns: current time step

Definition at line 64 of file CarModel.cpp.

const pose_ptr CarModel::getUpdate	(	const int	newSteering,
		const int	newSpeed,
		const ros::Time &	time
	)

Update the simulation with current control settings and time.

Given a current time, the simulation will calculate changes in position orientation as well as speed and rotation of the robot during the time interval from this to the previous update.

Parameters

[in]	newSteering	current steering level of the mobile robot.
[in]	newSpeed	current motor level of the mobile robot.
[in]	time	current Ros::Time

Returns: current position/speed/orientation/rotation of this mobile robot

Definition at line 28 of file CarModel.cpp.

const pose_ptr CarModel::getUpdateTwist	(	const twist_msg	cmd_vel,
		const ros::Time &	time
	)

Update the simulation with current motion parameters and time.

Given a current time, the simulation will calculate changes in position orientation as well as speed and rotation of the robot during the time interval from this to the previous update.

Parameters

[in]	cmd_vel	current speed and steering angle of the robot.
[in]	time	current Ros::Time

Returns: current position/speed/orientation/rotation of this mobile robot

Definition at line 46 of file CarModel.cpp.

const double CarModel::getVelocity ( ) const

Get current velocity of the mobile plattform.

Returns: current velocity

Definition at line 68 of file CarModel.cpp.

const double CarModel::getVx ( ) const

Get current velocity in x direction of the mobile plattform relative to the global coordinate system.

Returns: current velocity in x direction

Definition at line 75 of file CarModel.cpp.

const double CarModel::getVy ( ) const

Get current velocity in y direction of the mobile plattform relative to the global coordinate system.

Returns: current velocity in y direction

Definition at line 76 of file CarModel.cpp.

void CarModel::setAccelerationComponents ( const double prevV )

private

Calculate and set current acceleration components in x and y direction.

Parameters

[in] prevV previous velocity

Definition at line 155 of file CarModel.cpp.

void CarModel::setAngularVelocity ( const double oldYaw )

private

Calculate and set angular velocity by providing the orientation of the previous time step.

Parameters

[in] oldYaw previous orientation

Definition at line 115 of file CarModel.cpp.

void CarModel::setSteering ( const int steering )

private

Set current steering level.

Parameters

[in] steering current steering level

Definition at line 128 of file CarModel.cpp.

void CarModel::setVelocity ( const double newVel )

private

Set current velocity.

Parameters

[in] newVel current velocity

Definition at line 95 of file CarModel.cpp.

void CarModel::setVelocityComponents ( )

private

Calculate and set current velocity components in x and y direction.

Definition at line 150 of file CarModel.cpp.

void CarModel::speedToVelocity ( const int speed )

private

Conversion from given motor level to current velocity based on a lookup table.

Parameters

[in] speed motor level

Definition at line 111 of file CarModel.cpp.

void CarModel::steeringToAngle ( )

private

Conversion from current steering level to steering angle based on a lookup table.

Definition at line 146 of file CarModel.cpp.

Member Data Documentation

double CarModel::a_x

private

Current acceleration in x direction relative to the robot coordinate system.

Definition at line 158 of file CarModel.h.

double CarModel::a_y

private

Current acceleration in y direction relative to the robot coordinate system.

Definition at line 160 of file CarModel.h.

double CarModel::angleMax

private

Maximum steering angle in degrees

Definition at line 143 of file CarModel.h.

double CarModel::angularVelocity

private

Current angular velocity in rad/s

Definition at line 153 of file CarModel.h.

double CarModel::distance

private

Total driven distance

Definition at line 150 of file CarModel.h.

ForwardKinematics CarModel::fwdKin

private

Simulation of ackerman kinematics

Definition at line 140 of file CarModel.h.

ros::Time CarModel::lastUpdate

private

Ros time of last update

Definition at line 141 of file CarModel.h.

std::vector<double> CarModel::pose

private

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

Definition at line 151 of file CarModel.h.

double CarModel::speedMax

private

Maximum motor level

Definition at line 144 of file CarModel.h.

int CarModel::steering

private

Current steering level

Definition at line 146 of file CarModel.h.

double CarModel::steeringAngle

private

Current steering angle

Definition at line 147 of file CarModel.h.

double CarModel::steeringMax

private

Maximum steering level

Definition at line 145 of file CarModel.h.

double CarModel::timeStep

private

Current time step

Definition at line 148 of file CarModel.h.

double CarModel::v_x

private

Current velocity in x direction relative to the global coordinate system.

Definition at line 154 of file CarModel.h.

double CarModel::v_y

private

Current velocity in y direction relative to the global coordinate system.

Definition at line 156 of file CarModel.h.

double CarModel::velocity

private

Current velocity

Definition at line 149 of file CarModel.h.

double CarModel::vMax

private

Maximum velocity in m/s

Definition at line 142 of file CarModel.h.

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

Public Member Functions

Private Member Functions

Private Attributes

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation