Inertial Class Reference

A class for inertial information about a link. More...

#include <physics/physics.hh>

Public Member Functions
	Inertial ()
	Default Constructor. More...
	Inertial (double _mass)
	Constructor. More...
	Inertial (const Inertial &_inertial)
	Copy constructor. More...
virtual	~Inertial ()
	Destructor. More...
const math::Vector3 &	GetCoG () const
	Get the center of gravity. More...
Inertial	GetInertial (const math::Pose &_frameOffset) const
	Get equivalent Inertia values with the Link frame offset, while holding the Pose of CoG constant in the world frame. More...
double	GetIXX () const
	Get IXX. More...
double	GetIXY () const
	Get IXY. More...
double	GetIXZ () const
	Get IXZ. More...
double	GetIYY () const
	Get IYY. More...
double	GetIYZ () const
	Get IXZ. More...
double	GetIZZ () const
	Get IZZ. More...
double	GetMass () const
	Get the mass. More...
math::Matrix3	GetMOI (const math::Pose &_pose) const
	Get the equivalent inertia from a point in local Link frame If you specify GetMOI(this->GetPose()), you should get back the Moment of Inertia (MOI) exactly as specified in the SDF. More...
math::Matrix3	GetMOI () const
	returns Moments of Inertia as a Matrix3 More...
const math::Pose	GetPose () const
	Get the pose about which the mass and inertia matrix is specified in the Link frame. More...
math::Vector3	GetPrincipalMoments () const
	Get the principal moments of inertia (Ixx, Iyy, Izz). More...
math::Vector3	GetProductsofInertia () const
	Get the products of inertia (Ixy, Ixz, Iyz). More...
void	Load (sdf::ElementPtr _sdf)
	Load from SDF values. More...
Inertial	operator+ (const Inertial &_inertial) const
	Addition operator. More...
const Inertial &	operator+= (const Inertial &_inertial)
	Addition equal operator. More...
Inertial &	operator= (const Inertial &_inertial)
	Equal operator. More...
void	ProcessMsg (const msgs::Inertial &_msg)
	Update parameters from a message. More...
void	Reset ()
	Reset all the mass properties. More...
void	Rotate (const math::Quaternion &_rot)
	Rotate this mass. More...
void	SetCoG (double _cx, double _cy, double _cz)
	Set the center of gravity. More...
void	SetCoG (const math::Vector3 &_center)
	Set the center of gravity. More...
void	SetCoG (double _cx, double _cy, double _cz, double _rx, double _ry, double _rz)
	Set the center of gravity and rotation offset of inertial coordinate frame relative to Link frame. More...
void	SetCoG (const math::Pose &_c)
	Set the center of gravity. More...
void	SetInertiaMatrix (double _ixx, double _iyy, double _izz, double _ixy, double _ixz, double iyz)
	Set the mass matrix. More...
void	SetIXX (double _v)
	Set IXX. More...
void	SetIXY (double _v)
	Set IXY. More...
void	SetIXZ (double _v)
	Set IXZ. More...
void	SetIYY (double _v)
	Set IYY. More...
void	SetIYZ (double _v)
	Set IYZ. More...
void	SetIZZ (double _v)
	Set IZZ. More...
void	SetMass (double m)
	Set the mass. More...
void	SetMOI (const math::Matrix3 &_moi)
	Sets Moments of Inertia (MOI) from a Matrix3. More...
void	UpdateParameters (sdf::ElementPtr _sdf)
	update the parameters using new sdf values. More...

Friends
std::ostream &	operator<< (std::ostream &_out, const gazebo::physics::Inertial &_inertial)
	Output operator. More...

Detailed Description

A class for inertial information about a link.

Constructor & Destructor Documentation

Inertial

(

)

Default Constructor.

Inertial ( double  _mass )

explicit

Constructor.

Parameters

[in]

_mass

Mass value in kg if using metric.

Inertial

(

const Inertial &

_inertial

)

Copy constructor.

Parameters

[in]

_inertial

Inertial element to copy

virtual ~Inertial ( )

virtual

Destructor.

Member Function Documentation

const math::Vector3& GetCoG ( ) const

inline

Get the center of gravity.

Returns

The center of gravity.

References Pose::pos.

Inertial GetInertial

(

const math::Pose &

_frameOffset

)

const

Get equivalent Inertia values with the Link frame offset, while holding the Pose of CoG constant in the world frame.

Parameters

[in]

_frameOffset

amount to offset the Link frame by, this is a transform defined in the Link frame.

Returns

Inertial parameters with the shifted frame.

double GetIXX

(

)

const

Get IXX.

Returns

IXX value

double GetIXY

(

)

const

Get IXY.

Returns

IXY value

double GetIXZ

(

)

const

Get IXZ.

Returns

IXZ value

double GetIYY

(

)

const

Get IYY.

Returns

IYY value

double GetIYZ

(

)

const

Get IXZ.

Returns

IYZ value

double GetIZZ

(

)

const

Get IZZ.

Returns

IZZ value

double GetMass

(

)

const

Get the mass.

math::Matrix3 GetMOI

(

const math::Pose &

_pose

)

const

Get the equivalent inertia from a point in local Link frame If you specify GetMOI(this->GetPose()), you should get back the Moment of Inertia (MOI) exactly as specified in the SDF.

If _pose is different from pose of the Inertial block, then the MOI is rotated accordingly, and contributions from changes in MOI location location due to point mass is added to the final MOI.

Parameters

[in]

_pose

location in Link local frame

Returns

equivalent inertia at _pose

math::Matrix3 GetMOI

(

)

const

returns Moments of Inertia as a Matrix3

Returns

Moments of Inertia as a Matrix3

const math::Pose GetPose ( ) const

inline

Get the pose about which the mass and inertia matrix is specified in the Link frame.

Returns

The inertial pose.

math::Vector3 GetPrincipalMoments

(

)

const

Get the principal moments of inertia (Ixx, Iyy, Izz).

Returns

The principal moments.

math::Vector3 GetProductsofInertia

(

)

const

Get the products of inertia (Ixy, Ixz, Iyz).

Returns

The products of inertia.

void Load

(

sdf::ElementPtr

_sdf

)

Load from SDF values.

Parameters

[in]

_sdf

SDF value to load from.

Inertial operator+

(

const Inertial &

_inertial

)

const

Addition operator.

Assuming both CG and Moment of Inertia (MOI) are defined in the same reference Link frame. New CG is computed from masses and perspective offsets, and both MOI contributions relocated to the new cog.

Parameters

[in]

_inertial

Inertial to add.

Returns

The result of the addition.

const Inertial& operator+=

(

const Inertial &

_inertial

)

Addition equal operator.

Parameters

[in]

_inertial

Inertial to add.

Returns

Reference to this object.

Inertial& operator=

(

const Inertial &

_inertial

)

Equal operator.

Parameters

[in]

_inertial

Inertial to copy.

Returns

Reference to this object.

void ProcessMsg

(

const msgs::Inertial &

_msg

)

Update parameters from a message.

Parameters

[in]

_msg

Message to read

void Reset

(

)

Reset all the mass properties.

void Rotate

(

const math::Quaternion &

_rot

)

Rotate this mass.

Parameters

[in]

_rot

Rotation amount.

void SetCoG	(	double	_cx,
		double	_cy,
		double	_cz
	)

Set the center of gravity.

Parameters

[in]	_cx	X position.
[in]	_cy	Y position.
[in]	_cz	Z position.

void SetCoG

(

const math::Vector3 &

_center

)

Set the center of gravity.

Parameters

[in]

_center

Center of the gravity.

void SetCoG	(	double	_cx,
		double	_cy,
		double	_cz,
		double	_rx,
		double	_ry,
		double	_rz
	)

Set the center of gravity and rotation offset of inertial coordinate frame relative to Link frame.

Parameters

[in]	_cx	Center offset in x-direction in Link frame
[in]	_cy	Center offset in y-direction in Link frame
[in]	_cz	Center offset in z-direction in Link frame
[in]	_rx	Roll angle offset of inertial coordinate frame.
[in]	_ry	Pitch angle offset of inertial coordinate frame.
[in]	_rz	Yaw angle offset of inertial coordinate frame.

void SetCoG

(

const math::Pose &

_c

)

Set the center of gravity.

Parameters

[in]

_c

Transform to center of gravity.

void SetInertiaMatrix	(	double	_ixx,
		double	_iyy,
		double	_izz,
		double	_ixy,
		double	_ixz,
		double	iyz
	)

Set the mass matrix.

Parameters

[in]	_ixx	X second moment of inertia (MOI) about x axis.
[in]	_iyy	Y second moment of inertia about y axis.
[in]	_izz	Z second moment of inertia about z axis.
[in]	_ixy	XY inertia.
[in]	_ixz	XZ inertia.
[in]	_iyz	YZ inertia.

void SetIXX

(

double

_v

)

Set IXX.

Parameters

[in]

_v

IXX value

void SetIXY

(

double

_v

)

Set IXY.

Parameters

[in]

_v

IXY value

void SetIXZ

(

double

_v

)

Set IXZ.

Parameters

[in]

_v

IXZ value

void SetIYY

(

double

_v

)

Set IYY.

Parameters

[in]

_v

IYY value

void SetIYZ

(

double

_v

)

Set IYZ.

Parameters

[in]

_v

IXX value

void SetIZZ

(

double

_v

)

Set IZZ.

Parameters

[in]

_v

IZZ value

void SetMass

(

double

m

)

Set the mass.

void SetMOI

(

const math::Matrix3 &

_moi

)

Sets Moments of Inertia (MOI) from a Matrix3.

Parameters

[in]

Moments

of Inertia as a Matrix3

void UpdateParameters

(

sdf::ElementPtr

_sdf

)

update the parameters using new sdf values.

Parameters

[in]

_sdf

Update values from.

Friends And Related Function Documentation

std::ostream& operator<< ( std::ostream &  _out, const gazebo::physics::Inertial &  _inertial  )

friend

Output operator.

Parameters

[in]	_out	Output stream.
[in]	_inertial	Inertial object to output.

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

• Inertial.hh