ackermann::Limits Class Reference

Class used to apply known limits to a given desired control signal. More...

#include <Limits.hpp>

Public Member Functions
	Limits (const std::shared_ptr< const Params > &params)
	Constructor. More...
void	limit (const double current_speed, const double current_steering, const double current_steering_vel, double &desired_throttle, double &desired_steering, double &desired_steering_vel, double dt) const
	Apply known limits to the given controller command. More...
double	throttleToSpeed (double throttle) const
	Use Parameters structure to convert throttle to speed as a function of maximum allowable speed. More...
double	speedToThrottle (double speed) const
	Use Parameters structure to convert speed to throttle as a function of maximum allowable speed. More...
double	shortestArcToTurn (double current_heading, double desired_heading) const
	Calculate the direction to minimize turning angle (eg, don't turn 270deg right if you can turn 90deg left. More...
double	boundHeading (const double heading) const
	Bound heading to [-pi,pi) range; prevents odd behavior. More...

Detailed Description

Class used to apply known limits to a given desired control signal.

Constructor & Destructor Documentation

Limits()

ackermann::Limits::Limits ( const std::shared_ptr< const Params > &  params )

explicit

Constructor.

Parameters

params

Shared pointer detailing rover characteristic parameters

Member Function Documentation

boundHeading()

double ackermann::Limits::boundHeading

(

const double

heading

)

const

Bound heading to [-pi,pi) range; prevents odd behavior.

Parameters

current_heading	Current heading in radians
desired_heading	Desired heading in radians

Returns

Bound heading in radians

limit()

void ackermann::Limits::limit	(	const double	current_speed,
		const double	current_steering,
		const double	current_steering_vel,
		double &	desired_throttle,
		double &	desired_steering,
		double &	desired_steering_vel,
		double	dt
	)		const

Apply known limits to the given controller command.

Apply known kinematic constraints (velocity, acceleration, angular velocity, angular acceleration) to the given potential commands, and return the limited version. (Return paramaters noted)

Parameters

current_speed	Current speed in (m/s).
current_steering	Current commanded steering angle (rad).
desired_thottle	(Return Parameter) Desired throttle (generally [0,1]).
desired_steering	(Return Parameter) Desired steering angle (rad).
desired_steering_vel	(Return parameter) Desired steering velocity (rad/s).
dt	Fixed time step between commands (s).

Here is the call graph for this function:

shortestArcToTurn()

double ackermann::Limits::shortestArcToTurn	(	double	current_heading,
		double	desired_heading
	)		const

Calculate the direction to minimize turning angle (eg, don't turn 270deg right if you can turn 90deg left.

Parameters

current_heading	Current heading in radians
desired_heading	Desired heading in radians

Returns

Angle and direction (+/-) to turn (rad)

speedToThrottle()

double ackermann::Limits::speedToThrottle

(

double

speed

)

const

Use Parameters structure to convert speed to throttle as a function of maximum allowable speed.

Parameters

speed

Speed in range of [0,max_speed]

Returns

Throttle position estimate from speed (linear relationship) [0,1]

Here is the caller graph for this function:

throttleToSpeed()

double ackermann::Limits::throttleToSpeed

(

double

throttle

)

const

Use Parameters structure to convert throttle to speed as a function of maximum allowable speed.

Parameters

throttle

Throttle setting in range of generally [0,1]

Returns

Speed based on throttle input (linear relationship) (m/s)

Here is the caller graph for this function:

---

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

• include/Limits.hpp
• app/Limits.cpp