Detailed Description

template<typename T>
class drake::multibody::CurvilinearJoint< T >

A Joint that allows a body to move along a piecewise constant curvature path contained in a plane.

The path is specified as a PiecewiseConstantCurvatureTrajectory, refer to that class documentation for further details on parameterization, conventions and notation used.

This joint grants a single degree of freedom q that corresponds to the length s (in meters) along the path. The generalized velocity v = q̇ corresponds to the magnitude of the tangential velocity. We denote with F a frame on a "parent" body and with M a frame on a "child" body. For a given trajectory, this joint prescribes X_FM(q) = PiecewiseConstantCurvatureTrajectory::CalcPose(q).

Frame M is defined according to the convention documented in PiecewiseConstantCurvatureTrajectory. That is, axis Mx is the tangent to the trajectory, Mz equals the (constant) normal p̂ to the plane, and My = Mz x Mx. It is not required that M coincides with F at distance q = 0.

If the specified trajectory is periodic, the joint prescribes a trajectory of cycle length L that satisfies X_FP(s) = X_FP(s + k⋅L) ∀ k ∈ ℤ.

By default, the joint position limits are the endpoints for aperiodic paths, and (-∞, ∞) for periodic paths.

Template Parameters

T	The scalar type, which must be one of the default scalars.

#include <drake/multibody/tree/curvilinear_joint.h>

Public Types
template<typename Scalar >
using	Context = systems::Context< Scalar >

Public Member Functions
	CurvilinearJoint (const std::string &name, const Frame< T > &frame_on_parent, const Frame< T > &frame_on_child, const trajectories::PiecewiseConstantCurvatureTrajectory< double > &curvilinear_path, double damping=0)
	Constructor to create a curvilinear joint between two bodies so that frame F attached to the parent body P and frame M attached to the child body B, move relatively to one another along a planar curvilinear path. More...

	CurvilinearJoint (const std::string &name, const Frame< T > &frame_on_parent, const Frame< T > &frame_on_child, const trajectories::PiecewiseConstantCurvatureTrajectory< double > curvilinear_path, double pos_lower_limit, double pos_upper_limit, double damping=0)
	Constructor to create a curvilinear joint between two bodies so that frame F attached to the parent body P and frame M attached to the child body B, move relatively to one another along a planar curvilinear path. More...

	~CurvilinearJoint () override

const std::string &	type_name () const override
	Returns a string identifying the type of `this` joint, such as "revolute" or "prismatic". More...

double	default_damping () const
	Returns `this` joint's default damping constant in N⋅s/m. More...

void	set_default_damping (double damping)
	Sets the default value of viscous damping for this joint, in N⋅s/m. More...

double	position_lower_limit () const
	Returns the position lower limit for `this` joint in m. More...

double	position_upper_limit () const
	Returns the position upper limit for `this` joint in m. More...

double	velocity_lower_limit () const
	Returns the velocity lower limit for `this` joint in m/s. More...

double	velocity_upper_limit () const
	Returns the velocity upper limit for `this` joint in m/s. More...

double	acceleration_lower_limit () const
	Returns the acceleration lower limit for `this` joint in m/s². More...

double	acceleration_upper_limit () const
	Returns the acceleration upper limit for `this` joint in m/s². More...

const T &	get_distance (const systems::Context< T > &context) const
	Gets the travel distance of the joint from the provided context. More...

const CurvilinearJoint< T > &	set_distance (systems::Context< T > *context, const T &distance) const
	Sets the travel distance of the joint from the provided context. More...

void	set_random_distance_distribution (const symbolic::Expression &distance)
	Sets the random distribution for the distance along the path. More...

const T &	get_tangential_velocity (const systems::Context< T > &context) const
	Gets the tangential velocity in meters per second, i.e. More...

const CurvilinearJoint< T > &	set_tangential_velocity (systems::Context< T > *context, const T &tangential_velocity) const
	Sets the tangential velocity of the joint from the provided context. More...

const T &	GetDamping (const systems::Context< T > &context) const
	Returns the Context dependent damping coefficient stored as a parameter in `context`. More...

void	SetDamping (systems::Context< T > *context, const T &damping) const
	Sets the value of the viscous damping coefficient for this joint, stored as a parameter in `context`. More...

double	get_default_distance () const
	Gets the default travel distance along the path. More...

void	set_default_distance (double distance)
	Sets the default travel distance of this joint. More...

void	AddInForce (const systems::Context< T > &context, const T &force, MultibodyForces< T > *forces) const
	Adds into a MultibodyForces a generalized force on this joint. More...

Does not allow copy, move, or assignment
	CurvilinearJoint (const CurvilinearJoint &)=delete

CurvilinearJoint &	operator= (const CurvilinearJoint &)=delete

	CurvilinearJoint (CurvilinearJoint &&)=delete

CurvilinearJoint &	operator= (CurvilinearJoint &&)=delete

Public Member Functions inherited from Joint< T >
	Joint (const std::string &name, const Frame< T > &frame_on_parent, const Frame< T > &frame_on_child, VectorX< double > damping, const VectorX< double > &pos_lower_limits, const VectorX< double > &pos_upper_limits, const VectorX< double > &vel_lower_limits, const VectorX< double > &vel_upper_limits, const VectorX< double > &acc_lower_limits, const VectorX< double > &acc_upper_limits)
	Creates a joint between two Frame objects which imposes a given kinematic relation between frame F attached on the parent body P and frame M attached on the child body B. More...

	Joint (const std::string &name, const Frame< T > &frame_on_parent, const Frame< T > &frame_on_child, const VectorX< double > &pos_lower_limits, const VectorX< double > &pos_upper_limits, const VectorX< double > &vel_lower_limits, const VectorX< double > &vel_upper_limits, const VectorX< double > &acc_lower_limits, const VectorX< double > &acc_upper_limits)
	Additional constructor overload for joints with zero damping. More...

virtual	~Joint ()

JointIndex	index () const
	Returns this element's unique index. More...

int	ordinal () const
	Returns this element's unique ordinal. More...

const std::string &	name () const
	Returns the name of this joint. More...

const RigidBody< T > &	parent_body () const
	Returns a const reference to the parent body P. More...

const RigidBody< T > &	child_body () const
	Returns a const reference to the child body B. More...

const Frame< T > &	frame_on_parent () const
	Returns a const reference to the frame F attached on the parent body P. More...

const Frame< T > &	frame_on_child () const
	Returns a const reference to the frame M attached on the child body B. More...

int	velocity_start () const
	Returns the index to the first generalized velocity for this joint within the vector v of generalized velocities for the full multibody system. More...

int	num_velocities () const
	Returns the number of generalized velocities describing this joint. More...

int	position_start () const
	Returns the index to the first generalized position for this joint within the vector q of generalized positions for the full multibody system. More...

int	num_positions () const
	Returns the number of generalized positions describing this joint. More...

bool	can_rotate () const
	Returns true if this joint's mobility allows relative rotation of the two frames associated with this joint. More...

bool	can_translate () const
	Returns true if this joint's mobility allows relative translation of the two frames associated with this joint. More...

std::string	position_suffix (int position_index_in_joint) const
	Returns a string suffix (e.g. More...

std::string	velocity_suffix (int velocity_index_in_joint) const
	Returns a string suffix (e.g. More...

const T &	GetOnePosition (const systems::Context< T > &context) const
	Returns the position coordinate for joints with a single degree of freedom. More...

const T &	GetOneVelocity (const systems::Context< T > &context) const
	Returns the velocity coordinate for joints with a single degree of freedom. More...

void	AddInOneForce (const systems::Context< T > &context, int joint_dof, const T &joint_tau, MultibodyForces< T > *forces) const
	Adds into `forces` a force along the one of the joint's degrees of freedom indicated by index `joint_dof`. More...

void	AddInDamping (const systems::Context< T > &context, MultibodyForces< T > *forces) const
	Adds into `forces` the force due to damping within `this` joint. More...

void	Lock (systems::Context< T > *context) const
	Lock the joint. More...

void	Unlock (systems::Context< T > *context) const
	Unlock the joint. More...

bool	is_locked (const systems::Context< T > &context) const

const VectorX< double > &	default_damping_vector () const
	Returns all default damping coefficients for joints that model viscous damping, of size num_velocities(). More...

const VectorX< T > &	GetDampingVector (const systems::Context< T > &context) const
	Returns the Context dependent damping coefficients stored as parameters in `context`. More...

void	set_default_damping_vector (const VectorX< double > &damping)
	Sets the default value of the viscous damping coefficients for this joint. More...

void	SetDampingVector (systems::Context< T > *context, const VectorX< T > &damping) const
	Sets the value of the viscous damping coefficients for this joint, stored as parameters in `context`. More...

	Joint (const Joint &)=delete

Joint &	operator= (const Joint &)=delete

	Joint (Joint &&)=delete

Joint &	operator= (Joint &&)=delete

const VectorX< double > &	position_lower_limits () const
	Returns the position lower limits. More...

const VectorX< double > &	position_upper_limits () const
	Returns the position upper limits. More...

const VectorX< double > &	velocity_lower_limits () const
	Returns the velocity lower limits. More...

const VectorX< double > &	velocity_upper_limits () const
	Returns the velocity upper limits. More...

const VectorX< double > &	acceleration_lower_limits () const
	Returns the acceleration lower limits. More...

const VectorX< double > &	acceleration_upper_limits () const
	Returns the acceleration upper limits. More...

void	set_position_limits (const VectorX< double > &lower_limits, const VectorX< double > &upper_limits)
	Sets the position limits to `lower_limits` and `upper_limits`. More...

void	set_velocity_limits (const VectorX< double > &lower_limits, const VectorX< double > &upper_limits)
	Sets the velocity limits to `lower_limits` and `upper_limits`. More...

void	set_acceleration_limits (const VectorX< double > &lower_limits, const VectorX< double > &upper_limits)
	Sets the acceleration limits to `lower_limits` and `upper_limits`. More...

void	set_default_positions (const VectorX< double > &default_positions)
	Sets the default generalized position coordinates q₀ to `default_positions`. More...

const VectorX< double > &	default_positions () const
	Returns the default generalized position coordinates q₀. More...

void	SetPositions (systems::Context< T > *context, const Eigen::Ref< const VectorX< T >> &positions) const
	Sets in the given `context` the generalized position coordinates q for this joint to `positions`. More...

Eigen::Ref< const VectorX< T > >	GetPositions (const systems::Context< T > &context) const
	Returns the current value in the given `context` of the generalized coordinates q for this joint. More...

void	SetVelocities (systems::Context< T > *context, const Eigen::Ref< const VectorX< T >> &velocities) const
	Sets in the given `context` the generalized velocity coordinates v for this joint to `velocities`. More...

Eigen::Ref< const VectorX< T > >	GetVelocities (const systems::Context< T > &context) const
	Returns the current value in the given `context` of the generalized velocities v for this joint. More...

void	SetDefaultPose (const math::RigidTransform< double > &X_FM)
	Sets this joint's default generalized positions q₀ such that the pose of the child frame M in the parent frame F best matches the given pose. More...

math::RigidTransform< double >	GetDefaultPose () const
	Returns this joint's default pose as a RigidTransform X_FM. More...

void	SetPose (systems::Context< T > *context, const math::RigidTransform< T > &X_FM) const
	Sets in the given `context` this joint's generalized positions q such that the pose of the child frame M in the parent frame F best matches the given pose. More...

math::RigidTransform< T >	GetPose (const systems::Context< T > &context) const
	Returns this joint's current pose using its position coordinates q taken from the given `context` and converting that to a RigidTransform X_FM(q). More...

void	SetSpatialVelocity (systems::Context< T > *context, const SpatialVelocity< T > &V_FM) const
	Sets in the given `context` this joint's generalized velocities v such that the spatial velocity of the child frame M in the parent frame F best matches the given spatial velocity. More...

SpatialVelocity< T >	GetSpatialVelocity (const systems::Context< T > &context) const
	Given the generalized positions q and generalized velocities v for this joint in the given `context`, returns the cross-joint spatial velocity V_FM. More...

void	SetDefaultPosePair (const Quaternion< double > &q_FM, const Vector3< double > &p_FM)
	(Advanced) This is the same as SetDefaultPose() except it takes the pose as a (quaternion, translation vector) pair. More...

std::pair< Eigen::Quaternion< double >, Vector3< double > >	GetDefaultPosePair () const
	(Advanced) This is the same as GetDefaultPose() except it returns this joint's default pose as a (quaternion, translation vector) pair. More...

void	SetPosePair (systems::Context< T > *context, const Quaternion< T > &q_FM, const Vector3< T > &p_FM) const
	(Advanced) This is the same as SetPose() except it takes the pose as a (quaternion, translation vector) pair. More...

std::pair< Eigen::Quaternion< T >, Vector3< T > >	GetPosePair (const systems::Context< T > &context) const
	(Advanced) This is the same as GetPose() except it returns this joint's pose in the given `context` as a (quaternion, translation vector) pair. More...

Public Member Functions inherited from MultibodyElement< T >
virtual	~MultibodyElement ()

ModelInstanceIndex	model_instance () const
	Returns the ModelInstanceIndex of the model instance to which this element belongs. More...

template<typename = void>
const MultibodyPlant< T > &	GetParentPlant () const
	Returns the MultibodyPlant that owns this MultibodyElement. More...

void	DeclareParameters (internal::MultibodyTreeSystem< T > *tree_system)
	Declares MultibodyTreeSystem Parameters at MultibodyTreeSystem::Finalize() time. More...

void	SetDefaultParameters (systems::Parameters< T > *parameters) const
	Sets default values of parameters belonging to each MultibodyElement in `parameters` at a call to MultibodyTreeSystem::SetDefaultParameters(). More...

	MultibodyElement (const MultibodyElement &)=delete

MultibodyElement &	operator= (const MultibodyElement &)=delete

	MultibodyElement (MultibodyElement &&)=delete

MultibodyElement &	operator= (MultibodyElement &&)=delete

Static Public Attributes
static const char	kTypeName [] = "curvilinear"

Protected Member Functions
void	DoAddInOneForce (const systems::Context< T > &, int joint_dof, const T &joint_tau, MultibodyForces< T > *forces) const override
	Joint<T> override called through public NVI, Joint::AddInForce(). More...

void	DoAddInDamping (const systems::Context< T > &context, MultibodyForces< T > *forces) const override
	Joint<T> override called through public NVI, Joint::AddInDamping(). More...

Protected Member Functions inherited from Joint< T >
virtual void	DoSetDefaultPosePair (const Quaternion< double > &q_FM, const Vector3< double > &p_FM)
	Implementation of the NVI SetDefaultPose(). More...

virtual std::pair< Eigen::Quaternion< double >, Vector3< double > >	DoGetDefaultPosePair () const
	Implementation of the NVI GetDefaultPose(). More...

void	DoSetTopology (const internal::MultibodyTreeTopology &) override
	Implementation of the NVI SetTopology(). More...

const JointImplementation &	get_implementation () const
	Returns a const reference to the internal implementation of `this` joint. More...

bool	has_implementation () const
	Returns whether `this` joint owns a particular implementation. More...

std::pair< const Frame< T > , const Frame< T > >	tree_frames (bool use_reversed_mobilizer) const
	Utility for concrete joint implementations to use to select the inboard/outboard frames for a tree in the spanning forest, given whether they should be reversed from the parent/child frames that are members of this Joint object. More...

template<template< typename > class ConcreteMobilizer>
const ConcreteMobilizer< T > &	get_mobilizer_downcast () const
	(Internal use only) Returns the mobilizer implementing this joint, downcast to its specific type. More...

template<template< typename > class ConcreteMobilizer>
ConcreteMobilizer< T > &	get_mutable_mobilizer_downcast ()
	(Internal use only) Mutable flavor of get_mobilizer_downcast(). More...

Protected Member Functions inherited from MultibodyElement< T >
	MultibodyElement ()
	Default constructor made protected so that sub-classes can still declare their default constructors if they need to. More...

	MultibodyElement (ModelInstanceIndex model_instance)
	Constructor which allows specifying a model instance. More...

	MultibodyElement (ModelInstanceIndex model_instance, int64_t index)
	Both the model instance and element index are specified. More...

template<typename ElementIndexType >
ElementIndexType	index_impl () const
	Returns this element's unique index. More...

int	ordinal_impl () const
	Returns this element's unique ordinal. More...

const internal::MultibodyTree< T > &	get_parent_tree () const
	Returns a constant reference to the parent MultibodyTree that owns this element. More...

const internal::MultibodyTreeSystem< T > &	GetParentTreeSystem () const
	Returns a constant reference to the parent MultibodyTreeSystem that owns the parent MultibodyTree that owns this element. More...

void	SetTopology (const internal::MultibodyTreeTopology &tree)
	Gives MultibodyElement-derived objects the opportunity to retrieve their topology after MultibodyTree::Finalize() is invoked. More...

systems::NumericParameterIndex	DeclareNumericParameter (internal::MultibodyTreeSystem< T > *tree_system, const systems::BasicVector< T > &model_vector)
	To be used by MultibodyElement-derived objects when declaring parameters in their implementation of DoDeclareParameters(). More...

systems::AbstractParameterIndex	DeclareAbstractParameter (internal::MultibodyTreeSystem< T > *tree_system, const AbstractValue &model_value)
	To be used by MultibodyElement-derived objects when declaring parameters in their implementation of DoDeclareParameters(). More...

Friends
template<typename >
class	CurvilinearJoint

Member Typedef Documentation

◆ Context

using Context = systems::Context<Scalar>

Constructor & Destructor Documentation

◆ CurvilinearJoint() [1/4]

CurvilinearJoint ( const CurvilinearJoint< T > & )

delete

◆ CurvilinearJoint() [2/4]

CurvilinearJoint ( CurvilinearJoint< T > && )

delete

◆ CurvilinearJoint() [3/4]

CurvilinearJoint	(	const std::string &	name,
		const Frame< T > &	frame_on_parent,
		const Frame< T > &	frame_on_child,
		const trajectories::PiecewiseConstantCurvatureTrajectory< double > &	curvilinear_path,
		double	damping = `0`
	)

Constructor to create a curvilinear joint between two bodies so that frame F attached to the parent body P and frame M attached to the child body B, move relatively to one another along a planar curvilinear path.

See this class's documentation for further details on the definition of these frames and the curvilinear path.

This constructor signature creates a joint where the joint velocity and acceleration limits are (-∞, ∞). Position limits are (0, L) with L the length of the trajectory. If the trajectory is periodic, position limits are (-∞, ∞).

The first three arguments to this constructor are those of the Joint class constructor. See the Joint class's documentation for details. The additional parameters are:

Parameters

[in]	curvilinear_path	The curvilinear path for this joint, along which the child frame M moves relative to the parent frame F.
[in]	damping	Viscous damping coefficient, in N⋅s/m, used to model losses within the joint. The damping force (in N) is modeled as `f = -damping⋅v` along the tangent to the curve, i.e. opposing motion, with v the tangential velocity for `this` joint (see get_tangential_velocity()).

Exceptions

std::exception if damping is negative

◆ CurvilinearJoint() [4/4]

CurvilinearJoint	(	const std::string &	name,
		const Frame< T > &	frame_on_parent,
		const Frame< T > &	frame_on_child,
		const trajectories::PiecewiseConstantCurvatureTrajectory< double >	curvilinear_path,
		double	pos_lower_limit,
		double	pos_upper_limit,
		double	damping = `0`
	)

Constructor to create a curvilinear joint between two bodies so that frame F attached to the parent body P and frame M attached to the child body B, move relatively to one another along a planar curvilinear path.

See this class's documentation for further details on the definition of these frames and the path.

The first three arguments to this constructor are those of the Joint class constructor. See the Joint class's documentation for details. The additional parameters are:

Parameters

[in]	curvilinear_path	The curvilinear path for this joint, along which the child frame M moves relative to the parent frame F.
[in]	pos_lower_limit	Lower position limit, in meters, for the distance coordinate (see get_distance()).
[in]	pos_upper_limit	Upper position limit, in meters, for the distance coordinate (see get_distance()).
[in]	damping	Viscous damping coefficient, in N⋅s/m, used to model losses within the joint. The damping force (in N) is modeled as `f = -damping⋅v` along the tangent to the curve, i.e. opposing motion, with v the tangential velocity for `this` joint (see get_tangential_velocity()).

Exceptions

std::exception	if damping is negative.
std::exception	if pos_lower_limit > pos_upper_limit.

◆ ~CurvilinearJoint()

~CurvilinearJoint ( )

override

Member Function Documentation

◆ acceleration_lower_limit()

double acceleration_lower_limit ( ) const

Returns the acceleration lower limit for this joint in m/s².

◆ acceleration_upper_limit()

double acceleration_upper_limit ( ) const

Returns the acceleration upper limit for this joint in m/s².

◆ AddInForce()

void AddInForce	(	const systems::Context< T > &	context,
		const T &	force,
		MultibodyForces< T > *	forces
	)		const

Adds into a MultibodyForces a generalized force on this joint.

A generalized force for a curvilinear joint is equivalent to a force in Newtons applied along the path tangent direction (x-axis of frame M).

Parameters

[in]	context	The context of the model this joint belongs to.
[in]	force	The force to be applied, in Newtons.
[out]	forces	The MultibodyForces object to which the generalized force is added.

◆ default_damping()

double default_damping ( ) const

Returns this joint's default damping constant in N⋅s/m.

◆ DoAddInDamping()

void DoAddInDamping	(	const systems::Context< T > &	context,
		MultibodyForces< T > *	forces
	)		const

overrideprotectedvirtual

Joint<T> override called through public NVI, Joint::AddInDamping().

Arguments already checked to be valid by Joint::AddInDamping().

Adds a dissipative force according to the viscous law f = -d⋅v, where d is the damping coefficient (see default_damping()) and v the tangential velocity along the path.

Parameters

[in]	context	The context of the model this joint belongs to.
[out]	forces	The MultibodyForces object to which the damping force is added.

Reimplemented from Joint< T >.

◆ DoAddInOneForce()

void DoAddInOneForce	(	const systems::Context< T > &	,
		int	joint_dof,
		const T &	joint_tau,
		MultibodyForces< T > *	forces
	)		const

overrideprotectedvirtual

Joint<T> override called through public NVI, Joint::AddInForce().

Arguments already checked to be valid by Joint::AddInForce().

Parameters

[in]	joint_dof	The joint degree of freedom index, on which the force is added, which must be 0.
[in]	joint_tau	The force along the path's tangential axis to be added, in Newtons, applied to the child body.
[out]	forces	The MultibodyForces object to which the force is added.

See also: The public NVI AddInOneForce() for details.

Implements Joint< T >.

◆ get_default_distance()

double get_default_distance ( ) const

Gets the default travel distance along the path.

◆ get_distance()

const T& get_distance ( const systems::Context< T > & context ) const

Gets the travel distance of the joint from the provided context.

Parameters

[in] context The context of the model this joint belongs to.

Returns: The distance coordinate of the joint stored in the context.

◆ get_tangential_velocity()

const T& get_tangential_velocity ( const systems::Context< T > & context ) const

Gets the tangential velocity in meters per second, i.e.

the rate of change of this joint's travel distance (see get_distance()) from the provided context.

Parameters

[in] context The context of the model this joint belongs to.

Returns: The tangential velocity as stored in the provided context.

◆ GetDamping()

const T& GetDamping ( const systems::Context< T > & context ) const

Returns the Context dependent damping coefficient stored as a parameter in context.

Refer to default_damping() for details.

Parameters

[in] context The context of the model this joint belongs to.

Returns: The damping coefficient stored in the context, in N⋅s/m.

◆ operator=() [1/2]

CurvilinearJoint& operator= ( CurvilinearJoint< T > && )

delete

◆ operator=() [2/2]

CurvilinearJoint& operator= ( const CurvilinearJoint< T > & )

delete

◆ position_lower_limit()

double position_lower_limit ( ) const

Returns the position lower limit for this joint in m.

◆ position_upper_limit()

double position_upper_limit ( ) const

Returns the position upper limit for this joint in m.

◆ set_default_damping()

void set_default_damping ( double damping )

Sets the default value of viscous damping for this joint, in N⋅s/m.

Exceptions

std::exception if damping is negative.

Precondition: the MultibodyPlant must not be finalized.

◆ set_default_distance()

void set_default_distance ( double distance )

Sets the default travel distance of this joint.

Parameters

[in] distance The desired default distance of the joint in meters.

◆ set_distance()

const CurvilinearJoint<T>& set_distance	(	systems::Context< T > *	context,
		const T &	distance
	)		const

Sets the travel distance of the joint from the provided context.

Parameters

[in]	context	The context of the model this joint belongs to.
[in]	distance	The travel distance to be set in the context.

Returns: const reference to this joint.

◆ set_random_distance_distribution()

void set_random_distance_distribution ( const symbolic::Expression & distance )

Sets the random distribution for the distance along the path.

Parameters

[in] distance Expression defining the random distance distribution.

◆ set_tangential_velocity()

const CurvilinearJoint<T>& set_tangential_velocity	(	systems::Context< T > *	context,
		const T &	tangential_velocity
	)		const

Sets the tangential velocity of the joint from the provided context.

Parameters

[in]	context	The context of the model this joint belongs to.
[in]	tangential_velocity	The tangential velocity to be set in the context.

Returns: const reference to this joint.

◆ SetDamping()

void SetDamping	(	systems::Context< T > *	context,
		const T &	damping
	)		const

Sets the value of the viscous damping coefficient for this joint, stored as a parameter in context.

Refer to default_damping() for details.

Parameters

[out]	context	The context of the model this joint belongs to.
[in]	damping	The damping coefficient to be set in N⋅s/m.

Exceptions

std::exception if damping is negative.

◆ type_name()

const std::string& type_name ( ) const

overridevirtual

Returns a string identifying the type of this joint, such as "revolute" or "prismatic".

Implements Joint< T >.

◆ velocity_lower_limit()

double velocity_lower_limit ( ) const

Returns the velocity lower limit for this joint in m/s.

◆ velocity_upper_limit()

double velocity_upper_limit ( ) const

Returns the velocity upper limit for this joint in m/s.

Friends And Related Function Documentation

◆ CurvilinearJoint

friend class CurvilinearJoint

friend

Member Data Documentation

◆ kTypeName

const char kTypeName = "curvilinear"

static

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

drake/multibody/tree/curvilinear_joint.h

Detailed Description

template<typename T> class drake::multibody::CurvilinearJoint< T >

Public Types

Public Member Functions

Static Public Attributes

Protected Member Functions

Friends

Member Typedef Documentation

◆ Context

Constructor & Destructor Documentation

◆ CurvilinearJoint() [1/4]

◆ CurvilinearJoint() [2/4]

◆ CurvilinearJoint() [3/4]

◆ CurvilinearJoint() [4/4]

◆ ~CurvilinearJoint()

Member Function Documentation

◆ acceleration_lower_limit()

◆ acceleration_upper_limit()

◆ AddInForce()

◆ default_damping()

◆ DoAddInDamping()

◆ DoAddInOneForce()

◆ get_default_distance()

◆ get_distance()

◆ get_tangential_velocity()

◆ GetDamping()

◆ operator=() [1/2]

◆ operator=() [2/2]

◆ position_lower_limit()

◆ position_upper_limit()

◆ set_default_damping()

◆ set_default_distance()

◆ set_distance()

◆ set_random_distance_distribution()

◆ set_tangential_velocity()

◆ SetDamping()

◆ type_name()

◆ velocity_lower_limit()

◆ velocity_upper_limit()

Friends And Related Function Documentation

◆ CurvilinearJoint

Member Data Documentation

◆ kTypeName

template<typename T>
class drake::multibody::CurvilinearJoint< T >