SimbodyPhysics Class Reference

Simbody physics engine. More...

#include <SimbodyPhysics.hh>

Inherits PhysicsEngine.

Public Member Functions
	SimbodyPhysics (WorldPtr _world)
	Constructor. More...
virtual	~SimbodyPhysics ()
	Destructor. More...
virtual CollisionPtr	CreateCollision (const std::string &_type, LinkPtr _body)
	Create a collision. More...
CollisionPtr	CreateCollision (const std::string &_shapeType, const std::string &_linkName)
	Create a collision. More...
virtual JointPtr	CreateJoint (const std::string &_type, ModelPtr _parent)
	Create a new joint. More...
virtual LinkPtr	CreateLink (ModelPtr _parent)
	Create a new body. More...
virtual ModelPtr	CreateModel (BasePtr _parent)
	Create a new model. More...
virtual ShapePtr	CreateShape (const std::string &_shapeType, CollisionPtr _collision)
	Create a physics::Shape object. More...
virtual void	DebugPrint () const
	Debug print out of the physic engine state. More...
virtual void	Fini ()
	Finilize the physics engine. More...
virtual bool	GetAutoDisableFlag ()
	: Remove this function, and replace it with a more generic property map More...
ContactManager *	GetContactManager () const
	Get a pointer to the contact manger. More...
SimTK::MultibodySystem *	GetDynamicsWorld () const
	Register a joint with the dynamics world. More...
double	GetMaxStepSize () const
	Get max step size. More...
virtual boost::any	GetParam (const std::string &_key) const
	Get an parameter of the physics engine. More...
virtual bool	GetParam (const std::string &_key, boost::any &_value) const
	Get a parameter from the physics engine with a boolean to indicate success or failure. More...
boost::recursive_mutex *	GetPhysicsUpdateMutex () const
	returns a pointer to the PhysicsEngine::physicsUpdateMutex. More...
double	GetRealTimeUpdateRate () const
	Get real time update rate. More...
sdf::ElementPtr	GetSDF () const
	Get a pointer to the SDF element for this physics engine. More...
double	GetTargetRealTimeFactor () const
	Get target real time factor. More...
virtual std::string	GetType () const
	Return the physics engine type (ode|bullet|dart|simbody). More...
double	GetUpdatePeriod ()
	Get the simulation update period. More...
virtual void	Init ()
	Initialize the physics engine. More...
virtual void	InitForThread ()
	Init the engine for threads. More...
void	InitModel (const physics::ModelPtr _model)
	Add a Model to the Simbody system. More...
virtual void	Load (sdf::ElementPtr _sdf)
	Load the physics engine. More...
virtual void	Reset ()
	Rest the physics engine. More...
virtual void	SetAutoDisableFlag (bool _autoDisable)
	: Remove this function, and replace it with a more generic property map More...
virtual void	SetGravity (const ignition::math::Vector3d &_gravity)
	Set the gravity vector. More...
virtual void	SetMaxContacts (unsigned int _maxContacts)
	: Remove this function, and replace it with a more generic property map More...
void	SetMaxStepSize (double _stepSize)
	Set max step size. More...
virtual bool	SetParam (const std::string &_key, const boost::any &_value)
	Set a parameter of the physics engine. More...
void	SetRealTimeUpdateRate (double _rate)
	Set real time update rate. More...
virtual void	SetSeed (uint32_t _seed)
	Set the random number seed for the physics engine. More...
void	SetTargetRealTimeFactor (double _factor)
	Set target real time factor. More...
virtual void	UpdateCollision ()
	Update the physics engine collision. More...
virtual void	UpdatePhysics ()
	Update the physics engine. More...
WorldPtr	World () const
	Get a pointer to the world. More...

Static Public Member Functions
static SimTK::Transform	GetPose (sdf::ElementPtr _element)
	If the given element contains a <pose> element, return it as a Transform. More...
static std::string	GetTypeString (unsigned int _type)
	Convert Base::GetType() to string, this is needed by the MultibodyGraphMaker. More...
static std::string	GetTypeString (physics::Base::EntityType _type)
	Convert Base::GetType() to string, this is needed by the MultibodyGraphMaker. More...
static SimTK::Transform	Pose2Transform (const ignition::math::Pose3d &_pose)
	Convert the given pose in x,y,z,thetax,thetay,thetaz format to a Simbody Transform. More...
static SimTK::Quaternion	QuadToQuad (const ignition::math::Quaterniond &_q)
	Convert ignition::math::Quaterniond to SimTK::Quaternion. More...
static ignition::math::Quaterniond	QuadToQuadIgn (const SimTK::Quaternion &_q)
	Convert SimTK::Quaternion to ignition::math::Quaterniond. More...
static ignition::math::Pose3d	Transform2PoseIgn (const SimTK::Transform &_xAB)
	Convert a Simbody transform to a pose in x,y,z, thetax,thetay,thetaz format. More...
static ignition::math::Vector3d	Vec3ToVector3Ign (const SimTK::Vec3 &_v)
	Convert SimTK::Vec3 to ignition::math::Vector3d. More...
static SimTK::Vec3	Vector3ToVec3 (const ignition::math::Vector3d &_v)
	Convert ignition::math::Vector3d to SimTK::Vec3. More...

Public Attributes
SimTK::CompliantContactSubsystem	contact
SimTK::Force::DiscreteForces	discreteForces
SimTK::GeneralForceSubsystem	forces
SimTK::Force::Gravity	gravity
SimTK::Integrator *	integ
SimTK::SimbodyMatterSubsystem	matter
bool	simbodyPhysicsInitialized
	true if initialized More...
bool	simbodyPhysicsStepped
SimTK::MultibodySystem	system
SimTK::ContactTrackerSubsystem	tracker

Protected Member Functions
virtual void	OnPhysicsMsg (ConstPhysicsPtr &_msg)
	virtual callback for gztopic "~/physics". More...
virtual void	OnRequest (ConstRequestPtr &_msg)
	virtual callback for gztopic "~/request". More...

Protected Attributes
ContactManager *	contactManager
	Class that handles all contacts generated by the physics engine. More...
double	maxStepSize
	Real time update rate. More...
transport::NodePtr	node
	Node for communication. More...
ignition::transport::Node	nodeIgn
	Ignition node for communication. More...
transport::SubscriberPtr	physicsSub
	Subscribe to the physics topic. More...
boost::recursive_mutex *	physicsUpdateMutex
	Mutex to protect the update cycle. More...
double	realTimeUpdateRate
	Real time update rate. More...
transport::SubscriberPtr	requestSub
	Subscribe to the request topic. More...
transport::PublisherPtr	responsePub
	Response publisher. More...
ignition::transport::Node::Publisher	responsePubIgn
	Response publisher. More...
sdf::ElementPtr	sdf
	Our SDF values. More...
double	targetRealTimeFactor
	Target real time factor. More...
WorldPtr	world
	Pointer to the world. More...

Detailed Description

Simbody physics engine.

Constructor & Destructor Documentation

SimbodyPhysics ( WorldPtr  _world )

explicit

Constructor.

virtual ~SimbodyPhysics ( )

virtual

Destructor.

Member Function Documentation

virtual CollisionPtr CreateCollision ( const std::string &  _shapeType, LinkPtr  _link  )

virtual

Create a collision.

Parameters

[in]	_shapeType	Type of collision to create.
[in]	_link	Parent link.

Implements PhysicsEngine.

CollisionPtr CreateCollision ( const std::string &  _shapeType, const std::string &  _linkName  )

inherited

Create a collision.

Parameters

[in]	_shapeType	Type of collision to create.
[in]	_linkName	Name of the parent link.

virtual JointPtr CreateJoint ( const std::string &  _type, ModelPtr  _parent  )

virtual

Create a new joint.

Parameters

[in]	_type	Type of joint to create.
[in]	_parent	Model parent.

Implements PhysicsEngine.

virtual LinkPtr CreateLink ( ModelPtr  _parent )

virtual

Create a new body.

Parameters

[in]

_parent

Parent model for the link.

Implements PhysicsEngine.

virtual ModelPtr CreateModel ( BasePtr  _base )

virtual

Create a new model.

Parameters

[in]

_base

Boost shared pointer to a new model.

Reimplemented from PhysicsEngine.

virtual ShapePtr CreateShape ( const std::string &  _shapeType, CollisionPtr  _collision  )

virtual

Create a physics::Shape object.

Parameters

[in]	_shapeType	Type of shape to create.
[in]	_collision	Collision parent.

Implements PhysicsEngine.

virtual void DebugPrint ( ) const

virtual

Debug print out of the physic engine state.

Implements PhysicsEngine.

virtual void Fini ( )

virtual

Finilize the physics engine.

Reimplemented from PhysicsEngine.

virtual bool GetAutoDisableFlag ( )

inlinevirtualinherited

: Remove this function, and replace it with a more generic property map

access functions to set ODE parameters..

Returns

Auto disable flag.

ContactManager* GetContactManager ( ) const

inherited

Get a pointer to the contact manger.

Returns

Pointer to the contact manager.

SimTK::MultibodySystem* GetDynamicsWorld

(

)

const

Register a joint with the dynamics world.

double GetMaxStepSize ( ) const

inherited

Get max step size.

Returns

Max step size.

virtual boost::any GetParam ( const std::string &  _key ) const

virtual

Get an parameter of the physics engine.

Parameters

[in]

_attr

String key

See Also

SetParam

Returns

The value of the parameter

Reimplemented from PhysicsEngine.

virtual bool GetParam ( const std::string &  _key, boost::any &  _value  ) const

virtual

Get a parameter from the physics engine with a boolean to indicate success or failure.

Parameters

[in]	_key	Key of the accessed param
[out]	_value	Value of the accessed param

Returns

True if the parameter was successfully retrieved

Reimplemented from PhysicsEngine.

boost::recursive_mutex* GetPhysicsUpdateMutex ( ) const

inlineinherited

returns a pointer to the PhysicsEngine::physicsUpdateMutex.

Returns

Pointer to the physics mutex.

References PhysicsEngine::physicsUpdateMutex.

static SimTK::Transform GetPose ( sdf::ElementPtr  _element )

static

If the given element contains a <pose> element, return it as a Transform.

Otherwise return the identity Transform. If there is more than one <pose> element, only the first one is processed.

double GetRealTimeUpdateRate ( ) const

inherited

Get real time update rate.

Returns

Update rate

sdf::ElementPtr GetSDF ( ) const

inherited

Get a pointer to the SDF element for this physics engine.

Returns

Pointer to the physics SDF element.

double GetTargetRealTimeFactor ( ) const

inherited

Get target real time factor.

Returns

Target real time factor

virtual std::string GetType ( ) const

virtual

Return the physics engine type (ode|bullet|dart|simbody).

Returns

Type of the physics engine.

Implements PhysicsEngine.

static std::string GetTypeString ( unsigned int  _type )

static

Convert Base::GetType() to string, this is needed by the MultibodyGraphMaker.

Parameters

[in]

_type

Joint type returned by Joint::GetType().

Returns

a hard-coded string needed by the MultibodyGraphMaker.

static std::string GetTypeString ( physics::Base::EntityType  _type )

static

Convert Base::GetType() to string, this is needed by the MultibodyGraphMaker.

Parameters

[in]

_type

Joint type returned by Joint::GetType().

Returns

a hard-coded string needed by the MultibodyGraphMaker.

double GetUpdatePeriod ( )

inherited

Get the simulation update period.

Returns

Simulation update period.

virtual void Init ( )

virtual

Initialize the physics engine.

Implements PhysicsEngine.

virtual void InitForThread ( )

virtual

Init the engine for threads.

Implements PhysicsEngine.

void InitModel

(

const physics::ModelPtr

_model

)

Add a Model to the Simbody system.

Parameters

[in]

_model

Pointer to the model to add into Simbody.

virtual void Load ( sdf::ElementPtr  _sdf )

virtual

Load the physics engine.

Parameters

[in]

_sdf

Pointer to the SDF parameters.

Reimplemented from PhysicsEngine.

virtual void OnPhysicsMsg ( ConstPhysicsPtr &  _msg )

protectedvirtual

virtual callback for gztopic "~/physics".

Parameters

[in]

_msg

Physics message.

Reimplemented from PhysicsEngine.

virtual void OnRequest ( ConstRequestPtr &  _msg )

protectedvirtual

virtual callback for gztopic "~/request".

Parameters

[in]

_msg

Request message.

Reimplemented from PhysicsEngine.

static SimTK::Transform Pose2Transform ( const ignition::math::Pose3d &  _pose )

static

Convert the given pose in x,y,z,thetax,thetay,thetaz format to a Simbody Transform.

The rotation angles are interpreted as a body-fixed sequence, meaning we rotation about x, then about the new y, then about the now twice-rotated z.

Parameters

[in]

_pose

Ignition math Pose3d object

Returns

Simbody's SimTK::Transform object

static SimTK::Quaternion QuadToQuad ( const ignition::math::Quaterniond &  _q )

static

Convert ignition::math::Quaterniond to SimTK::Quaternion.

Parameters

[in]

_q

Ignition::math::Quaterniond object

Returns

Simbody's SimTK::Quaternion object

static ignition::math::Quaterniond QuadToQuadIgn ( const SimTK::Quaternion &  _q )

static

Convert SimTK::Quaternion to ignition::math::Quaterniond.

Parameters

[in]

_q

Simbody's SimTK::Quaternion object

Returns

Ignition::math::Quaterniond object

virtual void Reset ( )

virtual

Rest the physics engine.

Reimplemented from PhysicsEngine.

virtual void SetAutoDisableFlag ( bool  _autoDisable )

virtualinherited

: Remove this function, and replace it with a more generic property map

Access functions to set ODE parameters.

Parameters

[in]

_autoDisable

True to enable auto disabling of bodies.

virtual void SetGravity ( const ignition::math::Vector3d &  _gravity )

virtual

Set the gravity vector.

Parameters

[in]

_gravity

New gravity vector.

Implements PhysicsEngine.

virtual void SetMaxContacts ( unsigned int  _maxContacts )

virtualinherited

: Remove this function, and replace it with a more generic property map

access functions to set ODE parameters

Parameters

[in]

_maxContacts

Maximum number of contacts.

Reimplemented in ODEPhysics.

void SetMaxStepSize ( double  _stepSize )

inherited

Set max step size.

Parameters

[in]

_stepSize

Max step size.

virtual bool SetParam ( const std::string &  _key, const boost::any &  _value  )

virtual

Set a parameter of the physics engine.

See SetParam documentation for descriptions of duplicate parameters.

Parameters

[in]	_key	String key Below is a list of _key parameter definitions: "solver_type" (string) - returns solver used by engine, e.g. "sequential_impulse' for Bullet, "quick" for ODE "Featherstone and Lemkes" for DART and "Spatial Algebra and Elastic Foundation" for Simbody. -# "cfm" (double) - global CFM (ODE/Bullet) -# "erp" (double) - global ERP (ODE/Bullet) -# "precon_iters" (bool) - precondition iterations (experimental). (ODE) "iters" (int) - number of LCP PGS iterations. If sor_lcp_tolerance is negative, full iteration count is executed. Otherwise, PGS may stop iteration early if sor_lcp_tolerance is satisfied by the total RMS residual. "sor" (double) - relaxation parameter for Projected Gauss-Seidel (PGS) updates. (ODE/Bullet) "contact_max_correcting_vel" (double) - truncates correction impulses from ERP by this value. (ODE) "contact_surface_layer" (double) - ERP is 0 for interpenetration depths below this value. (ODE/Bullet) "max_contacts" (int) - max number of contact constraints between any pair of collision bodies. "min_step_size" (double) - minimum internal step size. (defined but not used in ode). "max_step_size" (double) - maximum physics step size when physics update step must return.
[in]	_value	The value to set to

Returns

true if SetParam is successful, false if operation fails.

Reimplemented from PhysicsEngine.

void SetRealTimeUpdateRate ( double  _rate )

inherited

Set real time update rate.

Parameters

[in]

_rate

Update rate

virtual void SetSeed ( uint32_t  _seed )

virtual

Set the random number seed for the physics engine.

Parameters

[in]

_seed

The random number seed.

Implements PhysicsEngine.

void SetTargetRealTimeFactor ( double  _factor )

inherited

Set target real time factor.

Parameters

[in]

_factor

Target real time factor

static ignition::math::Pose3d Transform2PoseIgn ( const SimTK::Transform &  _xAB )

static

Convert a Simbody transform to a pose in x,y,z, thetax,thetay,thetaz format.

Parameters

[in]

_xAB

Simbody's SimTK::Transform object

Returns

ignition::math::Pose3d object

virtual void UpdateCollision ( )

virtual

Update the physics engine collision.

This function works in tandem with PhysicsEngine::UpdatePhysics() to update the world. This function will be called even if the physics is disabled (when World::PhysicsEnabled()) returns false). Which updates are done in which of the two functions PhysicsEngine::UpdateCollision() and PhysicsEngine::UpdatePhysics() is to some extent left to the implementing physics engine. The intention is that PhysicsEngine::UpdateCollision() will update the collision states of the world, including contact information, and PhysicsEngine::UpdatePhysics() will update the dynamics of the world, i.e. advance the world and react to the collision state. However for some physics engines, both is done in one step, or providing the contact information separately in UpdateCollision() would mean double work, as it can't be avoided to be done again in PhysicsEngine::UpdatePhysics() - in this case it is better that PhysicsEngine::UpdateCollision does not actually update collision and contact information, and instead leaves it to UpdatePhysics(). There should be one exception however when it still does make this update: If World::PhysicsEnabled() returns false, and therefore PhysicsEngine::UpdatePhysics() will not be called in the update step, then PhysicsEngine::UpdateCollision will need to ensure that collision and contact information will still be updated.

Implements PhysicsEngine.

virtual void UpdatePhysics ( )

virtual

Update the physics engine.

Will only be called if the physics are enabled, which is the case when World::PhysicsEnabled() returns true.

See Also

PhysicsEngine::UpdateCollision()

Reimplemented from PhysicsEngine.

static ignition::math::Vector3d Vec3ToVector3Ign ( const SimTK::Vec3 &  _v )

static

Convert SimTK::Vec3 to ignition::math::Vector3d.

Parameters

[in]

_v

Simbody's SimTK::Vec3 object

Returns

ignition::math::Vector3d object

static SimTK::Vec3 Vector3ToVec3 ( const ignition::math::Vector3d &  _v )

static

Convert ignition::math::Vector3d to SimTK::Vec3.

Parameters

[in]

_v

Ignition math Vector3d object

Returns

Simbody's SimTK::Vec3 object

WorldPtr World ( ) const

inherited

Get a pointer to the world.

Returns

Pointer to the world.

Member Data Documentation

SimTK::CompliantContactSubsystem contact

ContactManager* contactManager

protectedinherited

Class that handles all contacts generated by the physics engine.

SimTK::Force::DiscreteForces discreteForces

SimTK::GeneralForceSubsystem forces

SimTK::Force::Gravity gravity

SimTK:: Integrator* integ

SimTK::SimbodyMatterSubsystem matter

double maxStepSize

protectedinherited

Real time update rate.

transport::NodePtr node

protectedinherited

Node for communication.

ignition::transport::Node nodeIgn

protectedinherited

Ignition node for communication.

transport::SubscriberPtr physicsSub

protectedinherited

Subscribe to the physics topic.

boost::recursive_mutex* physicsUpdateMutex

protectedinherited

Mutex to protect the update cycle.

Referenced by PhysicsEngine::GetPhysicsUpdateMutex().

double realTimeUpdateRate

protectedinherited

Real time update rate.

transport::SubscriberPtr requestSub

protectedinherited

Subscribe to the request topic.

transport::PublisherPtr responsePub

protectedinherited

Response publisher.

ignition::transport::Node::Publisher responsePubIgn

protectedinherited

Response publisher.

sdf::ElementPtr sdf

protectedinherited

Our SDF values.

bool simbodyPhysicsInitialized

true if initialized

bool simbodyPhysicsStepped

SimTK::MultibodySystem system

double targetRealTimeFactor

protectedinherited

Target real time factor.

SimTK::ContactTrackerSubsystem tracker

WorldPtr world

protectedinherited

Pointer to the world.

---

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

• SimbodyPhysics.hh