The Odometry class handles odometry readings (2D pose and velocity with related timestamp) More...

#include <odometry.h>

Public Types
typedef boost::function< void(double, double)>	IntegrationFunction
	Integration function, used to integrate the odometry:
Public Member Functions
double	getAngular () const
	angular velocity getter
double	getHeading () const
	heading getter
double	getLinear () const
	linear velocity getter
double	getX () const
	x position getter
double	getY () const
	y position getter
void	init (const ros::Time &time)
	Initialize the odometry.
	Odometry (size_t velocity_rolling_window_size=10)
	Constructor Timestamp will get the current time value Value will be set to zero.
void	setVelocityRollingWindowSize (size_t velocity_rolling_window_size)
	Velocity rolling window size setter.
void	setWheelParams (double track, double front_wheel_radius, double rear_wheel_radius, double wheel_base)
	Sets the wheel parameters: radius and separation.
bool	update (double front_wheel_angular_pos, double front_wheel_angular_vel, double rear_wheel_angular_pos, double rear_wheel_angular_vel, double front_steering, const ros::Time &time)
	Updates the odometry class with latest wheels and steering position.
void	updateOpenLoop (double linear, double angular, const ros::Time &time)
	Updates the odometry class with latest velocity command.
Private Types
typedef bacc::accumulator_set < double, bacc::stats < bacc::tag::rolling_mean > >	RollingMeanAcc
	Rolling mean accumulator and window:
typedef bacc::tag::rolling_window	RollingWindow
Private Member Functions
void	integrateExact (double linear, double angular)
	Integrates the velocities (linear and angular) using exact method.
void	integrateRungeKutta2 (double linear, double angular)
	Integrates the velocities (linear and angular) using 2nd order Runge-Kutta.
void	resetAccumulators ()
	Reset linear and angular accumulators.
Private Attributes
double	angular_
RollingMeanAcc	angular_acc_
double	front_wheel_radius_
double	heading_
ros::Time	last_update_timestamp_
double	left_wheel_old_pos_
	Previou wheel position/state [rad]:
double	linear_
	Current velocity:
RollingMeanAcc	linear_acc_
double	rear_wheel_radius_
double	right_wheel_old_pos_
ros::Time	timestamp_
	Current timestamp:
double	track_
	Wheel kinematic parameters [m]:
size_t	velocity_rolling_window_size_
	Rolling mean accumulators for the linar and angular velocities:
double	wheel_base_
double	wheel_old_pos_
double	x_
	Current pose:
double	y_

Detailed Description

The Odometry class handles odometry readings (2D pose and velocity with related timestamp)

Definition at line 19 of file odometry.h.

Member Typedef Documentation

typedef boost::function<void(double, double)> ackermann_controller::Odometry::IntegrationFunction

Integration function, used to integrate the odometry:

Definition at line 24 of file odometry.h.

typedef bacc::accumulator_set<double, bacc::stats<bacc::tag::rolling_mean> > ackermann_controller::Odometry::RollingMeanAcc [private]

Rolling mean accumulator and window:

Definition at line 125 of file odometry.h.

typedef bacc::tag::rolling_window ackermann_controller::Odometry::RollingWindow [private]

Definition at line 126 of file odometry.h.

Constructor & Destructor Documentation

ackermann_controller::Odometry::Odometry ( size_t velocity_rolling_window_size = 10 )

Constructor Timestamp will get the current time value Value will be set to zero.

Parameters:

velocity_rolling_window_size Rolling window size used to compute the velocity mean

Definition at line 9 of file odometry.cpp.

Member Function Documentation

double ackermann_controller::Odometry::getAngular ( ) const [inline]

angular velocity getter

Returns:: angular velocity [rad/s]

Definition at line 102 of file odometry.h.

double ackermann_controller::Odometry::getHeading ( ) const [inline]

heading getter

Returns:: heading [rad]

Definition at line 66 of file odometry.h.

double ackermann_controller::Odometry::getLinear ( ) const [inline]

linear velocity getter

Returns:: linear velocity [m/s]

Definition at line 93 of file odometry.h.

double ackermann_controller::Odometry::getX ( ) const [inline]

x position getter

Returns:: x position [m]

Definition at line 75 of file odometry.h.

double ackermann_controller::Odometry::getY ( ) const [inline]

y position getter

Returns:: y position [m]

Definition at line 84 of file odometry.h.

void ackermann_controller::Odometry::init ( const ros::Time & time )

Initialize the odometry.

Parameters:

time	Current time

Definition at line 30 of file odometry.cpp.

void ackermann_controller::Odometry::integrateExact	(	double	linear,
		double	angular
	)		`[private]`

Integrates the velocities (linear and angular) using exact method.

Other possible integration method provided by the class.

Parameters:

linear	Linear velocity [m] (linear displacement, i.e. m/s * dt) computed by encoders
angular	Angular velocity [rad] (angular displacement, i.e. m/s * dt) computed by encoders
linear
angular

Exact integration (should solve problems when angular is zero):

Definition at line 107 of file odometry.cpp.

void ackermann_controller::Odometry::integrateRungeKutta2	(	double	linear,
		double	angular
	)		`[private]`

Integrates the velocities (linear and angular) using 2nd order Runge-Kutta.

Parameters:

linear	Linear velocity [m] (linear displacement, i.e. m/s * dt) computed by encoders
angular	Angular velocity [rad] (angular displacement, i.e. m/s * dt) computed by encoders

Runge-Kutta 2nd order integration:

Definition at line 92 of file odometry.cpp.

void ackermann_controller::Odometry::resetAccumulators ( ) [private]

Reset linear and angular accumulators.

Definition at line 124 of file odometry.cpp.

void ackermann_controller::Odometry::setVelocityRollingWindowSize ( size_t velocity_rolling_window_size )

Velocity rolling window size setter.

Parameters:

velocity_rolling_window_size Velocity rolling window size

Definition at line 85 of file odometry.cpp.

void ackermann_controller::Odometry::setWheelParams	(	double	track,
		double	front_wheel_radius,
		double	rear_wheel_radius,
		double	wheel_base
	)

Sets the wheel parameters: radius and separation.

Parameters:

track	Seperation between left and right wheels [m]
front_wheel_radius	Wheel radius [m]
rear_wheel_radius	Wheel radius [m]
wheel_base	Wheel base [m]

Definition at line 77 of file odometry.cpp.

bool ackermann_controller::Odometry::update	(	double	front_wheel_angular_pos,
		double	front_wheel_angular_vel,
		double	rear_wheel_angular_pos,
		double	rear_wheel_angular_vel,
		double	front_steering,
		const ros::Time &	time
	)

Updates the odometry class with latest wheels and steering position.

Parameters:

front_wheel_angular_pos	Front wheel position [rad]
front_wheel_angular_vel	Front wheel angular speed [rad/s]
rear_wheel_angular_pos	Rear wheel position [rad]
rear_wheel_angular_vel	Rear wheel angular speed [rad/s]
front_steering	position [rad]
time	ROS time