Description

Closed-loop path-follower driver model.

A driver model that uses a path steering controller and a speed controller. The steering controller adjusts the steering input to follow the prescribed path. The output from the speed controller is used to adjust throttle and braking inputs in order to maintain the prescribed constant vehicle speed.

See also: ChPathSteeringController; ChAdaptiveSpeedController

#include <ChPathFollowerACCDriver.h>

Inheritance diagram for chrono::vehicle::ChPathFollowerACCDriver:

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Collaboration diagram for chrono::vehicle::ChPathFollowerACCDriver:

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Public Member Functions
	ChPathFollowerACCDriver (ChVehicle &vehicle, std::shared_ptr< ChBezierCurve > path, const std::string &path_name, double target_speed, double target_following_time, double target_min_distance, double current_distance, bool isClosedPath=false)
	Construct using the specified Bezier curve. More...

	ChPathFollowerACCDriver (ChVehicle &vehicle, const std::string &steering_filename, const std::string &speed_filename, std::shared_ptr< ChBezierCurve > path, const std::string &path_name, double target_speed, double target_following_time, double target_min_distance, double current_distance, bool isClosedPath=false)
	Construct using JSON specification files. More...

void	SetDesiredSpeed (double val)
	Set the desired vehicle speed.

void	SetDesiredFollowingTime (double val)
	Set the desired number of seconds of following distance.

void	SetDesiredFollowingMinDistance (double val)
	Set the desired min distance to the vehicle in front This comes into play especially at low to zero speeds.

void	SetCurrentDistance (double val)
	Set the distance to the vehicle in front that the control will track Typically this will be called at each time step.

void	SetThreshholdThrottle (double val)
	Specify the throttle value below which braking is enabled. More...

ChPathSteeringController &	GetSteeringController ()
	Get the underlying steering controller object.

ChAdaptiveSpeedController &	GetSpeedController ()
	Get the underlying speed controller object.

void	Reset ()
	Reset the underlying controllers.

virtual void	Advance (double step) override
	Advance the state of this driver system by the specified duration.

void	ExportPathPovray (const std::string &out_dir)
	Export the Bezier curve for POV-Ray postprocessing.

Public Member Functions inherited from chrono::vehicle::ChDriver
	ChDriver (ChVehicle &vehicle)

double	GetThrottle () const
	Get the driver throttle input (in the range [0,1])

double	GetSteering () const
	Get the driver steering input (in the range [-1,+1])

double	GetBraking () const
	Get the driver braking input (in the range [0,1])

Inputs	GetInputs () const
	Get all current inputs at once.

virtual void	Initialize ()
	Initialize this driver system.

virtual void	Synchronize (double time)
	Update the state of this driver system at the current time.

bool	LogInit (const std::string &filename)
	Initialize output file for recording driver inputs.

bool	Log (double time)
	Record the current driver inputs to the log file.

void	SetSteering (double val, double min_val=-1, double max_val=1)
	Overwrite the value for the driver steering input.

void	SetThrottle (double val, double min_val=0, double max_val=1)
	Overwrite the value for the driver throttle input.

void	SetBraking (double val, double min_val=0, double max_val=1)
	Overwrite the value for the driver braking input.

Additional Inherited Members
Protected Attributes inherited from chrono::vehicle::ChDriver
ChVehicle &	m_vehicle
	reference to associated vehicle

double	m_throttle
	current value of throttle input

double	m_steering
	current value of steering input

double	m_braking
	current value of braking input

Constructor & Destructor Documentation

◆ ChPathFollowerACCDriver() [1/2]

chrono::vehicle::ChPathFollowerACCDriver::ChPathFollowerACCDriver	(	ChVehicle &	vehicle,
		std::shared_ptr< ChBezierCurve >	path,
		const std::string &	path_name,
		double	target_speed,
		double	target_following_time,
		double	target_min_distance,
		double	current_distance,
		bool	isClosedPath = `false`
	)

Construct using the specified Bezier curve.

Parameters

vehicle	associated vehicle
path	Bezier curve with target path
path_name	name of the path curve
target_speed	constant target speed
target_following_time	seconds of following time
target_min_distance	min following distance
current_distance	current distance to the vehicle in front
isClosedPath	Treat the path as a closed loop

◆ ChPathFollowerACCDriver() [2/2]

chrono::vehicle::ChPathFollowerACCDriver::ChPathFollowerACCDriver	(	ChVehicle &	vehicle,
		const std::string &	steering_filename,
		const std::string &	speed_filename,
		std::shared_ptr< ChBezierCurve >	path,
		const std::string &	path_name,
		double	target_speed,
		double	target_following_time,
		double	target_min_distance,
		double	current_distance,
		bool	isClosedPath = `false`
	)

Construct using JSON specification files.

The two files must contain specification for the path-follower steering controller and the constant-speed controller, respectively.

Parameters

vehicle	associated vehicle
steering_filename	JSON file with steering controller specification
speed_filename	JSON file with speed controller specification
path	Bezier curve with target path
path_name	name of the path curve
target_speed	constant target speed
target_following_time	seconds of following time
target_min_distance	min following distance
current_distance	current distance to the vehicle in front
isClosedPath	Treat the path as a closed loop

Member Function Documentation

◆ SetThreshholdThrottle()

void chrono::vehicle::ChPathFollowerACCDriver::SetThreshholdThrottle ( double val )

inline

Specify the throttle value below which braking is enabled.

If the vehicle is moving faster than the set speed, the controller attempts to reduce speed either by reducing the throttle input (if the current throttle input is above the threshold value) or by applying brakes (otherwise).

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

/builds/uwsbel/chrono/src/chrono_vehicle/driver/ChPathFollowerACCDriver.h
/builds/uwsbel/chrono/src/chrono_vehicle/driver/ChPathFollowerACCDriver.cpp