joint_limits Namespace Reference

Classes
struct	JointControlInterfacesData
struct	JointInterfacesCommandLimiterData
class	JointLimiterInterface
struct	JointLimits
class	JointSaturationLimiter
class	JointSoftLimiter
struct	SoftJointLimits

Functions
	DEFINE_LIMIT_STRUCT (PositionLimits)
	DEFINE_LIMIT_STRUCT (VelocityLimits)
	DEFINE_LIMIT_STRUCT (EffortLimits)
	DEFINE_LIMIT_STRUCT (AccelerationLimits)
bool	is_limited (double value, double min, double max)
	Checks if a value is limited by the given limits.
PositionLimits	compute_position_limits (const joint_limits::JointLimits &limits, const std::optional< double > &act_vel, const std::optional< double > &act_pos, const std::optional< double > &prev_command_pos, double dt)
	Computes the position limits based on the velocity and acceleration limits.
VelocityLimits	compute_velocity_limits (const std::string &joint_name, const joint_limits::JointLimits &limits, const double &desired_vel, const std::optional< double > &act_pos, const std::optional< double > &prev_command_vel, double dt)
	Computes the velocity limits based on the position and acceleration limits.
EffortLimits	compute_effort_limits (const joint_limits::JointLimits &limits, const std::optional< double > &act_pos, const std::optional< double > &act_vel, double)
	Computes the effort limits based on the position and velocity limits.
AccelerationLimits	compute_acceleration_limits (const JointLimits &limits, double desired_acceleration, std::optional< double > actual_velocity)
	Computes the acceleration limits based on the change in velocity and acceleration and deceleration limits.
bool	declare_parameters (const std::string &joint_name, const rclcpp::node_interfaces::NodeParametersInterface::SharedPtr &param_itf, const rclcpp::node_interfaces::NodeLoggingInterface::SharedPtr &logging_itf)
bool	declare_parameters (const std::string &joint_name, const rclcpp::Node::SharedPtr &node)
bool	declare_parameters (const std::string &joint_name, const rclcpp_lifecycle::LifecycleNode::SharedPtr &lifecycle_node)
bool	get_joint_limits (const std::string &joint_name, const rclcpp::node_interfaces::NodeParametersInterface::SharedPtr &param_itf, const rclcpp::node_interfaces::NodeLoggingInterface::SharedPtr &logging_itf, JointLimits &limits)
	Populate a JointLimits instance from the node parameters.
bool	get_joint_limits (const std::string &joint_name, const rclcpp::Node::SharedPtr &node, JointLimits &limits)
bool	get_joint_limits (const std::string &joint_name, const rclcpp_lifecycle::LifecycleNode::SharedPtr &lifecycle_node, JointLimits &limits)
bool	check_for_limits_update (const std::string &joint_name, const std::vector< rclcpp::Parameter > &parameters, const rclcpp::node_interfaces::NodeLoggingInterface::SharedPtr &logging_itf, JointLimits &updated_limits)
bool	get_joint_limits (const std::string &joint_name, const rclcpp::node_interfaces::NodeParametersInterface::SharedPtr &param_itf, const rclcpp::node_interfaces::NodeLoggingInterface::SharedPtr &logging_itf, SoftJointLimits &soft_limits)
	Populate a SoftJointLimits instance from the ROS parameter server.
bool	get_joint_limits (const std::string &joint_name, const rclcpp::Node::SharedPtr &node, SoftJointLimits &soft_limits)
bool	get_joint_limits (const std::string &joint_name, const rclcpp_lifecycle::LifecycleNode::SharedPtr &lifecycle_node, SoftJointLimits &soft_limits)
bool	check_for_limits_update (const std::string &joint_name, const std::vector< rclcpp::Parameter > &parameters, const rclcpp::node_interfaces::NodeLoggingInterface::SharedPtr &logging_itf, SoftJointLimits &updated_limits)
bool	getJointLimits (urdf::JointConstSharedPtr urdf_joint, JointLimits &limits)
	Populate a JointLimits instance from URDF joint data.
bool	getSoftJointLimits (urdf::JointConstSharedPtr urdf_joint, SoftJointLimits &soft_limits)
	Populate a SoftJointLimits instance from URDF joint data.

Detailed Description

Author

Denis Stogl

Adolfo Rodriguez Tsouroukdissian

Adrià Roig Moreno

Dr. Denis Stogl

Sai Kishor Kothakota

Function Documentation

check_for_limits_update() [1/2]

bool joint_limits::check_for_limits_update ( const std::string &  joint_name, const std::vector< rclcpp::Parameter > &  parameters, const rclcpp::node_interfaces::NodeLoggingInterface::SharedPtr &  logging_itf, JointLimits &  updated_limits  )

inline

Check if any of updated parameters are related to JointLimits.

This method is intended to be used in the parameters update callback. It is recommended that it's result is temporarily stored and synchronized with the JointLimits structure in the main loop.

Parameters

[in]	joint_name	Name of the joint whose limits should be checked.
[in]	parameters	List of the parameters that should be checked if they belong to this structure and that are used for updating the internal values.
[in]	logging_itf	node logging interface to provide log errors.
[out]	updated_limits	structure with updated JointLimits. It is recommended that the currently used limits are stored into this structure before calling this method.

check_for_limits_update() [2/2]

bool joint_limits::check_for_limits_update ( const std::string &  joint_name, const std::vector< rclcpp::Parameter > &  parameters, const rclcpp::node_interfaces::NodeLoggingInterface::SharedPtr &  logging_itf, SoftJointLimits &  updated_limits  )

inline

Check if any of updated parameters are related to SoftJointLimits.

This method is intended to be used in the parameters update callback. It is recommended that it's result is temporarily stored and synchronized with the SoftJointLimits structure in the main loop.

Parameters

[in]	joint_name	Name of the joint whose limits should be checked.
[in]	parameters	List of the parameters that should be checked if they belong to this structure and that are used for updating the internal values.
[in]	logging_itf	node logging interface to provide log errors.
[out]	updated_limits	structure with updated SoftJointLimits. It is recommended that the currently used limits are stored into this structure before calling this method.

compute_acceleration_limits()

AccelerationLimits joint_limits::compute_acceleration_limits	(	const JointLimits &	limits,
		double	desired_acceleration,
		std::optional< double >	actual_velocity
	)

Computes the acceleration limits based on the change in velocity and acceleration and deceleration limits.

Parameters

limits	The joint limits.
desired_acceleration	The desired acceleration.
actual_velocity	The actual velocity of the joint.

Returns

The acceleration limits, first is the lower limit and second is the upper limit.

compute_effort_limits()

EffortLimits joint_limits::compute_effort_limits	(	const joint_limits::JointLimits &	limits,
		const std::optional< double > &	act_pos,
		const std::optional< double > &	act_vel,
		double
	)

Computes the effort limits based on the position and velocity limits.

Parameters

limits	The joint limits.
act_pos	The actual position of the joint.
act_vel	The actual velocity of the joint.
dt	The time step.

Returns

The effort limits, first is the lower limit and second is the upper limit.

compute_position_limits()

PositionLimits joint_limits::compute_position_limits	(	const joint_limits::JointLimits &	limits,
		const std::optional< double > &	act_vel,
		const std::optional< double > &	act_pos,
		const std::optional< double > &	prev_command_pos,
		double	dt
	)

Computes the position limits based on the velocity and acceleration limits.

Parameters

limits	The joint limits.
act_vel	The actual velocity of the joint.
prev_command_pos	The previous commanded position of the joint.
dt	The time step.

Returns

The position limits, first is the lower limit and second is the upper limit.

compute_velocity_limits()

VelocityLimits joint_limits::compute_velocity_limits	(	const std::string &	joint_name,
		const joint_limits::JointLimits &	limits,
		const double &	desired_vel,
		const std::optional< double > &	act_pos,
		const std::optional< double > &	prev_command_vel,
		double	dt
	)

Computes the velocity limits based on the position and acceleration limits.

Parameters

joint_name	The name of the joint.
limits	The joint limits.
act_pos	The actual position of the joint.
prev_command_vel	The previous commanded velocity of the joint.
dt	The time step.

Returns

The velocity limits, first is the lower limit and second is the upper limit.

declare_parameters() [1/3]

bool joint_limits::declare_parameters ( const std::string &  joint_name, const rclcpp::Node::SharedPtr &  node  )

inline

Declare JointLimits and SoftJointLimits parameters for joint with joint_name for the node object. This is a convenience function. For parameters structure see the underlying declare_parameters function.

Parameters

[in]	joint_name	name of the joint for which parameters will be declared.
[in]	node	node for parameters should be declared.

Returns

True if parameters are successfully declared, false otherwise.

declare_parameters() [2/3]

bool joint_limits::declare_parameters ( const std::string &  joint_name, const rclcpp::node_interfaces::NodeParametersInterface::SharedPtr &  param_itf, const rclcpp::node_interfaces::NodeLoggingInterface::SharedPtr &  logging_itf  )

inline

Declare JointLimits and SoftJointLimits parameters for joint with joint_name using node parameters interface param_itf.

The following parameter structure is declared with base name joint_limits.joint_name:

has_position_limits: bool
min_position: double
max_position: double
has_velocity_limits: bool
max_velocity: double
has_acceleration_limits: bool
max_acceleration: double
has_deceleration_limits: bool
max_deceleration: double
has_jerk_limits: bool
max_jerk: double
has_effort_limits: bool
max_effort: double
angle_wraparound: bool
has_soft_limits: bool
k_position: double
k_velocity: double
soft_lower_limit: double
soft_upper_limit: double

Parameters

[in]	joint_name	name of the joint for which parameters will be declared.
[in]	param_itf	node parameters interface object to access parameters.
[in]	logging_itf	node logging interface to log if error happens.

Returns

True if parameters are successfully declared, false otherwise.

declare_parameters() [3/3]

bool joint_limits::declare_parameters ( const std::string &  joint_name, const rclcpp_lifecycle::LifecycleNode::SharedPtr &  lifecycle_node  )

inline

Declare JointLimits and SoftJointLimits parameters for joint with joint_name for the lifecycle_node object. This is a convenience function. For parameters structure see the underlying declare_parameters function.

Parameters

[in]	joint_name	name of the joint for which parameters will be declared.
[in]	lifecycle_node	lifecycle node for parameters should be declared.

Returns

True if parameters are successfully declared, false otherwise.

get_joint_limits() [1/6]

bool joint_limits::get_joint_limits ( const std::string &  joint_name, const rclcpp::Node::SharedPtr &  node, JointLimits &  limits  )

inline

Populate a JointLimits instance from the node parameters. This is a convenience function. For parameters structure see the underlying get_joint_limits function.

Parameters

[in]	joint_name	Name of joint whose limits are to be fetched.
[in]	node	Node object for which parameters should be fetched.
[out]	limits	Where joint limit data gets written into. Limits specified in the parameter server will overwrite existing values. Values in limits not specified in the parameter server remain unchanged.

Returns

True if a limits specification is found, false otherwise.

get_joint_limits() [2/6]

bool joint_limits::get_joint_limits ( const std::string &  joint_name, const rclcpp::Node::SharedPtr &  node, SoftJointLimits &  soft_limits  )

inline

Populate a JointLimits instance from the node parameters. This is a convenience function. For parameters structure see the underlying get_joint_limits function.

Parameters

[in]	joint_name	Name of joint whose limits are to be fetched.
[in]	node	Node object for which parameters should be fetched.
[out]	soft_limits	Where soft joint limit data gets written into. Limits specified in the parameter server will overwrite existing values.

Returns

True if a soft limits specification is found, false otherwise.

get_joint_limits() [3/6]

bool joint_limits::get_joint_limits ( const std::string &  joint_name, const rclcpp::node_interfaces::NodeParametersInterface::SharedPtr &  param_itf, const rclcpp::node_interfaces::NodeLoggingInterface::SharedPtr &  logging_itf, JointLimits &  limits  )

inline

Populate a JointLimits instance from the node parameters.

It is assumed that parameter structure is the following:

has_position_limits: bool
min_position: double
max_position: double
has_velocity_limits: bool
max_velocity: double
has_acceleration_limits: bool
max_acceleration: double
has_deceleration_limits: bool
max_deceleration: double
has_jerk_limits: bool
max_jerk: double
has_effort_limits: bool
max_effort: double
angle_wraparound: bool  # will be ignored if there are position limits

Unspecified parameters are not added to the joint limits specification. A specification in a yaml would look like this:

<node_name>
  ros__parameters:
    joint_limits:
      foo_joint:
        has_position_limits: true
        min_position: 0.0
        max_position: 1.0
        has_velocity_limits: true
        max_velocity: 2.0
        has_acceleration_limits: true
        max_acceleration: 5.0
        has_deceleration_limits: true
        max_deceleration: 7.5
        has_jerk_limits: true
        max_jerk: 100.0
        has_effort_limits: true
        max_effort: 20.0
      bar_joint:
        has_position_limits: false   # Continuous joint
        angle_wraparound: true       # available only for continuous joints
        has_velocity_limits: true
        max_velocity: 4.0

Parameters

[in]	joint_name	Name of joint whose limits are to be fetched, e.g., "foo_joint".
[in]	param_itf	node parameters interface of the node where parameters are specified.
[in]	logging_itf	node logging interface to provide log errors.
[out]	limits	Where joint limit data gets written into. Limits specified in the parameter server will overwrite existing values. Values in limits not specified in the parameter server remain unchanged.

Returns

True if a limits specification is found (i.e., the joint_limits/joint_name parameter exists in node), false otherwise.

get_joint_limits() [4/6]

bool joint_limits::get_joint_limits ( const std::string &  joint_name, const rclcpp::node_interfaces::NodeParametersInterface::SharedPtr &  param_itf, const rclcpp::node_interfaces::NodeLoggingInterface::SharedPtr &  logging_itf, SoftJointLimits &  soft_limits  )

inline

Populate a SoftJointLimits instance from the ROS parameter server.

It is assumed that the parameter structure is the following:

has_soft_limits: bool
k_position: double
k_velocity: double
soft_lower_limit: double
soft_upper_limit: double

Only completely specified soft joint limits specifications will be considered valid. For example a valid yaml configuration would look like:

<node_name>
  ros__parameters:
    joint_limits:
      foo_joint:
        soft_lower_limit: 0.0
        soft_upper_limit: 1.0
        k_position: 10.0
        k_velocity: 10.0

Parameters

[in]	joint_name	Name of joint whose limits are to be fetched, e.g., "foo_joint".
[in]	param_itf	node parameters interface of the node where parameters are specified.
[in]	logging_itf	node logging interface to provide log errors.
[out]	soft_limits	Where soft joint limit data gets written into. Limits specified in the parameter server will overwrite existing values.

Returns

True if a complete soft limits specification is found (ie. if all k_position, k_velocity, soft_lower_limit and soft_upper_limit exist in joint_limits/joint_name namespace), false otherwise.

get_joint_limits() [5/6]

bool joint_limits::get_joint_limits ( const std::string &  joint_name, const rclcpp_lifecycle::LifecycleNode::SharedPtr &  lifecycle_node, JointLimits &  limits  )

inline

Populate a JointLimits instance from the node parameters. This is a convenience function. For parameters structure see the underlying get_joint_limits function.

Parameters

[in]	joint_name	Name of joint whose limits are to be fetched.
[in]	lifecycle_node	Lifecycle node object for which parameters should be fetched.
[out]	limits	Where joint limit data gets written into. Limits specified in the parameter server will overwrite existing values. Values in limits not specified in the parameter server remain unchanged.

Returns

True if a limits specification is found, false otherwise.

get_joint_limits() [6/6]

bool joint_limits::get_joint_limits ( const std::string &  joint_name, const rclcpp_lifecycle::LifecycleNode::SharedPtr &  lifecycle_node, SoftJointLimits &  soft_limits  )

inline

Populate a JointLimits instance from the node parameters. This is a convenience function. For parameters structure see the underlying get_joint_limits function.

Parameters

[in]	joint_name	Name of joint whose limits are to be fetched.
[in]	lifecycle_node	Lifecycle node object for which parameters should be fetched.
[out]	soft_limits	Where soft joint limit data gets written into. Limits specified in the parameter server will overwrite existing values.

Returns

True if a soft limits specification is found, false otherwise.

getJointLimits()

bool joint_limits::getJointLimits ( urdf::JointConstSharedPtr  urdf_joint, JointLimits &  limits  )

inline

Populate a JointLimits instance from URDF joint data.

Parameters

[in]	urdf_joint	URDF joint.
[out]	limits	Where URDF joint limit data gets written into. Limits in urdf_joint will overwrite existing values. Values in limits not present in urdf_joint remain unchanged.

Returns

True if urdf_joint has a valid limits specification, false otherwise.

getSoftJointLimits()

bool joint_limits::getSoftJointLimits ( urdf::JointConstSharedPtr  urdf_joint, SoftJointLimits &  soft_limits  )

inline

Populate a SoftJointLimits instance from URDF joint data.

Parameters

[in]	urdf_joint	URDF joint.
[out]	soft_limits	Where URDF soft joint limit data gets written into.

Returns

True if urdf_joint has a valid soft limits specification, false otherwise.

is_limited()

bool joint_limits::is_limited	(	double	value,
		double	min,
		double	max
	)

Checks if a value is limited by the given limits.

Parameters

value	The value to check.
min	The minimum limit.
max	The maximum limit.

Returns

True if the value is limited, false otherwise.