SimTK::MobilizedBody::Ball Class Reference

Three mobilities -- unrestricted orientation modeled with a quaternion which is never singular. More...

#include <MobilizedBody_Ball.h>

Inheritance diagram for SimTK::MobilizedBody::Ball:

List of all members.

Public Member Functions
	Ball ()
	Default constructor provides an empty handle that can be assigned to reference any MobilizedBody::Ball.
	Ball (MobilizedBody &parent, const Transform &X_PF, const Body &bodyInfo, const Transform &X_BM, Direction=Forward)
	Create a Ball mobilizer between an existing parent (inboard) body P and a new child (outboard) body B created by copying the given bodyInfo into a privately-owned Body within the constructed MobilizedBody object.
	Ball (MobilizedBody &parent, const Body &bodyInfo, Direction=Forward)
	Abbreviated constructor you can use if the mobilizer frames are coincident with the parent and child body frames.
Ball &	addBodyDecoration (const Transform &X_BD, const DecorativeGeometry &g)
	Add decorative geometry specified relative to the new (outboard) body's reference frame B.
Ball &	addOutboardDecoration (const Transform &X_MD, const DecorativeGeometry &g)
	Add decorative geometry specified relative to the outboard mobilizer frame M attached to body B.
Ball &	addInboardDecoration (const Transform &X_FD, const DecorativeGeometry &g)
	Add decorative geometry specified relative to the inboard mobilizer frame F attached to the parent body P.
Ball &	setDefaultInboardFrame (const Transform &X_PF)
	Change this mobilizer's frame F on the parent body P.
Ball &	setDefaultOutboardFrame (const Transform &X_BM)
	Change this mobilizer's frame M fixed on this (the outboard) body B.
Ball &	setDefaultRotation (const Rotation &R_FM)
Rotation	getDefaultRotation () const
Ball &	setDefaultRadius (Real r)
Real	getDefaultRadius () const
const Quaternion &	getDefaultQ () const
Ball &	setDefaultQ (const Quaternion &q)
const Vec4 &	getQ (const State &) const
const Vec4 &	getQDot (const State &) const
const Vec4 &	getQDotDot (const State &) const
const Vec3 &	getU (const State &) const
const Vec3 &	getUDot (const State &) const
void	setQ (State &, const Vec4 &) const
void	setU (State &, const Vec3 &) const
const Vec4 &	getMyPartQ (const State &, const Vector &qlike) const
const Vec3 &	getMyPartU (const State &, const Vector &ulike) const
Vec4 &	updMyPartQ (const State &, Vector &qlike) const
Vec3 &	updMyPartU (const State &, Vector &ulike) const

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Detailed Description

Three mobilities -- unrestricted orientation modeled with a quaternion which is never singular.

A modeling option allows the joint to use a 1-2-3 Euler sequence (identical to a Gimbal) instead. The three generalized speeds u for this mobilizer are always the three measure numbers of the angular velocity vector w_FM, the relative angular velocity of the outboard M frame in the inboard F frame, expressed in the F frame. That is unchanged by setting the "use Euler angles" modeling option, so the generalized speeds differ from those of a Gimbal joint. Note that qdot != u for this mobilizer.

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Constructor & Destructor Documentation

SimTK::MobilizedBody::Ball::Ball

(

)

[inline]

Default constructor provides an empty handle that can be assigned to reference any MobilizedBody::Ball.

SimTK::MobilizedBody::Ball::Ball	(	MobilizedBody &	parent,
		const Transform &	X_PF,
		const Body &	bodyInfo,
		const Transform &	X_BM,
		Direction	= Forward
	)

Create a Ball mobilizer between an existing parent (inboard) body P and a new child (outboard) body B created by copying the given bodyInfo into a privately-owned Body within the constructed MobilizedBody object.

Specify the mobilizer frames F fixed to parent P and M fixed to child B.

See also:

MobilizedBody for a diagram and explanation of terminology.

SimTK::MobilizedBody::Ball::Ball	(	MobilizedBody &	parent,
		const Body &	bodyInfo,
		Direction	= Forward
	)

Abbreviated constructor you can use if the mobilizer frames are coincident with the parent and child body frames.

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Member Function Documentation

Ball& SimTK::MobilizedBody::Ball::addBodyDecoration	(	const Transform &	X_BD,
		const DecorativeGeometry &	geometry
	)		[inline]

Add decorative geometry specified relative to the new (outboard) body's reference frame B.

Note that the body itself may already have had some decorative geometry on it when it was first put into this MobilizedBody; this just adds more and the returned index is larger. Use the underlying Body object's accessors to find this decorative geometry again. The given geometry object is copied here; we do not keep a reference to the supplied object.

Reimplemented from SimTK::MobilizedBody.

Ball& SimTK::MobilizedBody::Ball::addOutboardDecoration	(	const Transform &	X_MD,
		const DecorativeGeometry &	geometry
	)		[inline]

Add decorative geometry specified relative to the outboard mobilizer frame M attached to body B.

If body B already has decorative geometry on it, this just adds some more, but kept in a separate list from the body decorations and inboard decorations. Returns a unique index that can be used to identify this outboard decoration later (numbered starting from zero for outboard decorations only).

Reimplemented from SimTK::MobilizedBody.

Ball& SimTK::MobilizedBody::Ball::addInboardDecoration	(	const Transform &	X_FD,
		const DecorativeGeometry &	geometry
	)		[inline]

Add decorative geometry specified relative to the inboard mobilizer frame F attached to the parent body P.

If body P already has decorative geometry on it, this just adds some more, but kept in a separate list from the body decorations and outboard decorations. Returns a unique index that can be used to identify this inboard decoration later (numbered starting from zero for inboard decorations only).

Reimplemented from SimTK::MobilizedBody.

Ball& SimTK::MobilizedBody::Ball::setDefaultInboardFrame

(

const Transform &

X_PF

)

[inline]

Change this mobilizer's frame F on the parent body P.

Calling this method invalidates the MobilizedBody's topology, so the containing matter subsystem's realizeTopology() method must be called again. A reference to this MobilizedBody is returned so that this can be chained like an assignment operator.

Reimplemented from SimTK::MobilizedBody.

Ball& SimTK::MobilizedBody::Ball::setDefaultOutboardFrame

(

const Transform &

X_BM

)

[inline]

Change this mobilizer's frame M fixed on this (the outboard) body B.

Calling this method invalidates the MobilizedBody's topology, so the containing matter subsystem's realizeTopology() method must be called again. A reference to this MobilizedBody is returned so that this can be chained like an assignment operator.

Reimplemented from SimTK::MobilizedBody.

Ball& SimTK::MobilizedBody::Ball::setDefaultRotation

(

const Rotation &

R_FM

)

[inline]

Rotation SimTK::MobilizedBody::Ball::getDefaultRotation

(

)

const [inline]

Ball& SimTK::MobilizedBody::Ball::setDefaultRadius

(

Real

r

)

Real SimTK::MobilizedBody::Ball::getDefaultRadius

(

)

const

const Quaternion& SimTK::MobilizedBody::Ball::getDefaultQ

(

)

const

Ball& SimTK::MobilizedBody::Ball::setDefaultQ

(

const Quaternion &

q

)

const Vec4& SimTK::MobilizedBody::Ball::getQ

(

const State &

)

const

const Vec4& SimTK::MobilizedBody::Ball::getQDot

(

const State &

)

const

const Vec4& SimTK::MobilizedBody::Ball::getQDotDot

(

const State &

)

const

const Vec3& SimTK::MobilizedBody::Ball::getU

(

const State &

)

const

const Vec3& SimTK::MobilizedBody::Ball::getUDot

(

const State &

)

const

void SimTK::MobilizedBody::Ball::setQ	(	State &	,
		const Vec4 &
	)		const

void SimTK::MobilizedBody::Ball::setU	(	State &	,
		const Vec3 &
	)		const

const Vec4& SimTK::MobilizedBody::Ball::getMyPartQ	(	const State &	,
		const Vector &	qlike
	)		const

const Vec3& SimTK::MobilizedBody::Ball::getMyPartU	(	const State &	,
		const Vector &	ulike
	)		const

Vec4& SimTK::MobilizedBody::Ball::updMyPartQ	(	const State &	,
		Vector &	qlike
	)		const

Vec3& SimTK::MobilizedBody::Ball::updMyPartU	(	const State &	,
		Vector &	ulike
	)		const

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

• MobilizedBody_Ball.h