Tracked vehicle controller which can be attached to a model with any number of left and right tracks. The system should be attached to a model. Each track has to have a TrackController system configured and running. More...

#include <TrackedVehicle.hh>

Public Member Functions
	TrackedVehicle ()
	Constructor.

	~TrackedVehicle () override
	Destructor.

void	Configure (const Entity &_entity, const std::shared_ptr< const sdf::Element > &_sdf, EntityComponentManager &_ecm, EventManager &_eventMgr) override
	Configure the system.

void	PostUpdate (const UpdateInfo &_info, const EntityComponentManager &_ecm) override

void	PreUpdate (const UpdateInfo &_info, EntityComponentManager &_ecm) override

Public Member Functions inherited from System
	System ()=default
	Constructor.

virtual	~System ()=default
	Destructor.

Additional Inherited Members
Public Types inherited from System
using	PriorityType = int32_t
	Signed integer type used for specifying priority of the execution order of PreUpdate and Update phases.

Static Public Attributes inherited from System
static constexpr PriorityType	kDefaultPriority = {0}
	Default priority value for execution order of the PreUpdate and Update phases.

static constexpr std::string_view	kPriorityElementName
	Name of the XML element from which the priority value will be parsed.

Detailed Description

Tracked vehicle controller which can be attached to a model with any number of left and right tracks. The system should be attached to a model. Each track has to have a TrackController system configured and running.

So far, this system only supports tracks that are parallel along a common axis (other designs are possible, but not implemented).

System Parameters

<left_track>: Configuration of a left track link. This element can appear multiple times, and must appear at least once.
<right_track>: Configuration of a right track link. This element can appear multiple times, and must appear at least once.
<left_track>, <right_track> subelements:
- <link>: The link representing the track. Required parameter.
- <velocity_topic>: The topic on which the track accepts velocity commands (defaults to /model/${model_name}/link/${link_name}/track_cmd_vel).
- <center_of_rotation_topic>: The topic on which the track accepts center of rotation commands (defaults to /model/${model_name}/link/${link_name}/track_cmd_center_of_rotation)
<tracks_separation>: Distance between tracks, in meters. Required parameter.
<track_height>: Height of the tracks, in meters (used for computing odometry). Required parameter.
<steering_efficiency>: Initial steering efficiency. Defaults to 0.5.
<debug>: If 1, the system will output debugging info and visualizations. Defaults to 0.
<linear_velocity>: Limiter of linear velocity of the vehicle. Please note that the tracks can each have their own speed limitations. If the element is not specified, the velocities etc. have no implicit limits.
- <min_velocity>/<max_velocity> Min/max velocity of the vehicle (m/s). If not specified, the velocity is not limited (however the physics will, in the end, have some implicit limit).
- <min_acceleration>/<max_acceleration> Min/max acceleration of the vehicle (m/s^2). If not specified, the acceleration is not limited (however the physics will, in the end, have some implicit limit).
- <min_jerk>/<max_jerk> Min/max jerk of the vehicle (m/s^3). If not specified, the acceleration is not limited (however the physics will, in the end, have some implicit limit).
<angular_velocity>: Limiter of angular velocity of the vehicle. Please note that the tracks can each have their own speed limitations. If the element is not specified, the velocities etc. have no implicit limits.
- <min_velocity>/<max_velocity> Min/max velocity of the vehicle (rad/s). If not specified, the velocity is not limited (however the physics will, in the end, have some implicit limit).
- <min_acceleration>/<max_acceleration> Min/max acceleration of the vehicle (rad/s^2). If not specified, the velocity is not limited (however the physics will, in the end, have some implicit limit).
- <min_jerk>/<max_jerk> Min/max jerk of the vehicle (rad/s^3). If not specified, the velocity is not limited (however the physics will, in the end, have some implicit limit).
<odom_publish_frequency>: Odometry publication frequency. This element is optional, and the default value is 50Hz.
<topic>: Custom topic that this system will subscribe to in order to receive command velocity messages. This element is optional, and the default value is /model/{model_name}/cmd_vel.
<steering_efficiency_topic>: Custom topic that this system will subscribe to in order to receive steering efficiency messages. This element is optional, and the default value is /model/{model_name}/steering_efficiency.
<odom_topic>: Custom topic on which this system will publish odometry messages. This element is optional, and the default value is /model/{model_name}/odometry.
<tf_topic>: Custom topic on which this system will publish the transform from frame_id to child_frame_id. This element is optional, and the default value is /model/{model_name}/tf.
<frame_id>: Custom frame_id field that this system will use as the origin of the odometry transform in both the <tf_topic> gz.msgs.Pose_V message and the <odom_topic> gz.msgs.Odometry message. This element if optional, and the default value is {model_name}/odom.
<child_frame_id>: Custom child_frame_id that this system will use as the target of the odometry trasnform in both the <tf_topic> gz.msgs.Pose_V message and the <odom_topic> gz.msgs.Odometry message. This element if optional, and the default value is {model_name}/{link_name}.

Examples

See example usage in world example/tracked_vehicle_simple.sdf.

Constructor & Destructor Documentation

◆ TrackedVehicle()

TrackedVehicle ( )

Constructor.

◆ ~TrackedVehicle()

~TrackedVehicle ( )

override

Destructor.

Member Function Documentation

◆ Configure()

void Configure	(	const Entity &	_entity,
		const std::shared_ptr< const sdf::Element > &	_sdf,
		EntityComponentManager &	_ecm,
		EventManager &	_eventMgr
	)

overridevirtual

Configure the system.

Parameters

[in]	_entity	The entity this plugin is attached to.
[in]	_sdf	The SDF Element associated with this system plugin.
[in]	_ecm	The EntityComponentManager of the given simulation instance.
[in]	_eventMgr	The EventManager of the given simulation instance.