SimTK::Constraint::Rod Class Reference

This constraint consists of one constraint equation that enforces a constant distance between a point on one body and a point on another body. More...

#include <Constraint.h>

Inheritance diagram for SimTK::Constraint::Rod:

List of all members.

Public Member Functions
	Rod (MobilizedBody &body1, MobilizedBody &body2, Real defaultLength=1)
	Rod (MobilizedBody &body1, const Vec3 &defaultPoint1, MobilizedBody &body2, const Vec3 &defaultPoint2, Real defaultLength=1)
Rod &	setDefaultPointOnBody1 (const Vec3 &)
Rod &	setDefaultPointOnBody2 (const Vec3 &)
Rod &	setDefaultRodLength (Real)
MobilizedBodyIndex	getBody1MobilizedBodyIndex () const
MobilizedBodyIndex	getBody2MobilizedBodyIndex () const
const Vec3 &	getDefaultPointOnBody1 () const
const Vec3 &	getDefaultPointOnBody2 () const
Real	getDefaultRodLength () const
const Vec3 &	getPointOnBody1 (const State &) const
const Vec3 &	getPointOnBody2 (const State &) const
Real	getRodLength (const State &) const
Real	getPositionError (const State &) const
Real	getVelocityError (const State &) const
Real	getAccelerationError (const State &) const
Real	getMultiplier (const State &) const
Real	getRodTension (const State &) const
	SimTK_INSERT_DERIVED_HANDLE_DECLARATIONS (Rod, RodImpl, Constraint)

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Detailed Description

This constraint consists of one constraint equation that enforces a constant distance between a point on one body and a point on another body.

This is like connecting them by a rigid, massless rod with ball joints at either end. The constraint is enforced by a force acting along the rod with opposite signs at either end. When positive, this represents tension in the rod pulling the points together; when negative it represents compression keeping the points separated.

Warning:

You can't use this to enforce a distance of zero between two points. That takes three constraints because there is no restriction on the force direction. For a distance of zero (i.e., you want the points to be coincident) use a Ball constraint, a.k.a. CoincidentPoints constraint.

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Constructor & Destructor Documentation

SimTK::Constraint::Rod::Rod	(	MobilizedBody &	body1,
		MobilizedBody &	body2,
		Real	defaultLength = 1
	)

SimTK::Constraint::Rod::Rod	(	MobilizedBody &	body1,
		const Vec3 &	defaultPoint1,
		MobilizedBody &	body2,
		const Vec3 &	defaultPoint2,
		Real	defaultLength = 1
	)

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Member Function Documentation

Rod& SimTK::Constraint::Rod::setDefaultPointOnBody1

(

const Vec3 &

)

Rod& SimTK::Constraint::Rod::setDefaultPointOnBody2

(

const Vec3 &

)

Rod& SimTK::Constraint::Rod::setDefaultRodLength

(

Real

)

MobilizedBodyIndex SimTK::Constraint::Rod::getBody1MobilizedBodyIndex

(

)

const

MobilizedBodyIndex SimTK::Constraint::Rod::getBody2MobilizedBodyIndex

(

)

const

const Vec3& SimTK::Constraint::Rod::getDefaultPointOnBody1

(

)

const

const Vec3& SimTK::Constraint::Rod::getDefaultPointOnBody2

(

)

const

Real SimTK::Constraint::Rod::getDefaultRodLength

(

)

const

const Vec3& SimTK::Constraint::Rod::getPointOnBody1

(

const State &

)

const

const Vec3& SimTK::Constraint::Rod::getPointOnBody2

(

const State &

)

const

Real SimTK::Constraint::Rod::getRodLength

(

const State &

)

const

Real SimTK::Constraint::Rod::getPositionError

(

const State &

)

const

Real SimTK::Constraint::Rod::getVelocityError

(

const State &

)

const

Real SimTK::Constraint::Rod::getAccelerationError

(

const State &

)

const

Real SimTK::Constraint::Rod::getMultiplier

(

const State &

)

const

Real SimTK::Constraint::Rod::getRodTension

(

const State &

)

const

SimTK::Constraint::Rod::SimTK_INSERT_DERIVED_HANDLE_DECLARATIONS	(	Rod	,
		RodImpl	,
		Constraint
	)

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

• Constraint.h