MassProperties Class Reference

This class contains the mass, center of mass, and inertia of a rigid body B. More...

#include <MassProperties.h>

List of all members.

Public Member Functions
	MassProperties ()
	MassProperties (const Real &m, const Vec3 &com, const Inertia &inertia)
MassProperties &	setMassProperties (const Real &m, const Vec3 &com, const Inertia &inertia)
	Set mass, center of mass, and inertia.
const Real &	getMass () const
const Vec3 &	getMassCenter () const
const Inertia &	getInertia () const
Inertia	calcCentralInertia () const
Inertia	calcShiftedInertia (const Vec3 &newOriginB) const
Inertia	calcTransformedInertia (const Transform &X_BC) const
MassProperties	calcShiftedMassProps (const Vec3 &newOriginB) const
MassProperties	calcTransformedMassProps (const Transform &X_BC) const
MassProperties	reexpress (const Rotation &R_BC) const
bool	isExactlyMassless () const
bool	isNearlyMassless (const Real &tol=SignificantReal) const
bool	isExactlyCentral () const
bool	isNearlyCentral (const Real &tol=SignificantReal) const
SpatialMat	toSpatialMat () const
Mat66	toMat66 () const
	Caution: this does not have the same layout in memory as a SpatialMat, although it has the same logical layout.

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Detailed Description

This class contains the mass, center of mass, and inertia of a rigid body B.

The center of mass is a vector from B's origin, expressed in the B frame. The inertia is taken about the B origin, and expressed in B.

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Constructor & Destructor Documentation

MassProperties

(

)

[inline]

References MassProperties::setMassProperties().

Referenced by MassProperties::calcShiftedMassProps(), MassProperties::calcTransformedMassProps(), and MassProperties::reexpress().

MassProperties	(	const Real &	m,
		const Vec3 &	com,
		const Inertia &	inertia
	)			[inline]

References MassProperties::setMassProperties().

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Member Function Documentation

Inertia calcCentralInertia

(

)

const [inline]

Referenced by MobilizedBody::calcBodyMomentumAboutBodyMassCenterInGround(), and MassProperties::calcShiftedInertia().

Inertia calcShiftedInertia

(

const Vec3 &

newOriginB

)

const [inline]

References MassProperties::calcCentralInertia().

Referenced by MobilizedBody::calcBodyInertiaAboutAnotherBodyStation(), MassProperties::calcShiftedMassProps(), and MassProperties::calcTransformedInertia().

MassProperties calcShiftedMassProps

(

const Vec3 &

newOriginB

)

const [inline]

References MassProperties::calcShiftedInertia(), and MassProperties::MassProperties().

Inertia calcTransformedInertia

(

const Transform &

X_BC

)

const [inline]

References MassProperties::calcShiftedInertia(), Transform::p(), Transform::R(), and MassProperties::reexpress().

Referenced by MassProperties::calcTransformedMassProps().

MassProperties calcTransformedMassProps

(

const Transform &

X_BC

)

const [inline]

References MassProperties::calcTransformedInertia(), and MassProperties::MassProperties().

const Inertia& getInertia

(

)

const [inline]

const Real& getMass

(

)

const [inline]

Referenced by MobilizedBody::calcBodyMomentumAboutBodyMassCenterInGround().

const Vec3& getMassCenter

(

)

const [inline]

Referenced by MobilizedBody::calcBodyMomentumAboutBodyMassCenterInGround().

bool isExactlyCentral

(

)

const [inline]

bool isExactlyMassless

(

)

const [inline]

bool isNearlyCentral

(

const Real &

tol = SignificantReal

)

const [inline]

References Vec< M, ELT, STRIDE >::normSqr().

bool isNearlyMassless

(

const Real &

tol = SignificantReal

)

const [inline]

MassProperties reexpress

(

const Rotation &

R_BC

)

const [inline]

References MassProperties::MassProperties(), and Inertia::reexpress().

Referenced by MobilizedBody::calcBodySpatialInertiaMatrixInGround(), MassProperties::calcTransformedInertia(), MobilizedBody::expressMassPropertiesInAnotherBodyFrame(), and MobilizedBody::expressMassPropertiesInGroundFrame().

MassProperties& setMassProperties	(	const Real &	m,
		const Vec3 &	com,
		const Inertia &	inertia
	)			[inline]

Set mass, center of mass, and inertia.

Behaves like an assignment in that a reference to the modified MassProperties object is returned.

Referenced by MassProperties::MassProperties().

Mat66 toMat66

(

)

const [inline]

Caution: this does not have the same layout in memory as a SpatialMat, although it has the same logical layout.

References SimTK::crossMat(), Mat< M, N, ELT, CS, RS >::getSubMat(), Inertia::toMat33(), and Mat< M, N, ELT, CS, RS >::updSubMat().

SpatialMat toSpatialMat

(

)

const [inline]

References SimTK::crossMat(), and Inertia::toMat33().

Referenced by MobilizedBody::calcBodyMomentumAboutBodyOriginInGround(), and MobilizedBody::calcBodySpatialInertiaMatrixInGround().

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

• MassProperties.h