wbc::types Namespace Reference

Classes
class	Contact
	Describes a rigid contact between a robot link and the environment. This can be either a point or surface contact. More...
class	JointCommand
class	JointLimits
class	JointState
	The JointState class describes either the state or the command for a set of joints, i.e., its actual or target position, velocity, acceleration and effort. More...
class	Limits
class	Pose
class	RigidBodyState
class	SpatialAcceleration
class	Twist
class	Wrench

Enumerations
enum	CommandMode {   UNSET = -1 , POSITION = 0 , VELOCITY = 1 , ACCELERATION = 2 ,   EFFORT = 3 }

Functions
SpatialAcceleration	operator* (const Pose &transform, const SpatialAcceleration &acc_in)
Twist	operator* (const Pose &transform, const Twist &twist_in)
types::Twist	operator- (const types::Pose &a, const types::Pose &b)
Wrench	operator* (const Pose &transform, const Wrench &wrench_in)

Enumeration Type Documentation

CommandMode

enum wbc::types::CommandMode

Enumerator
UNSET
POSITION
VELOCITY
ACCELERATION
EFFORT

Function Documentation

operator*() [1/3]

SpatialAcceleration wbc::types::operator*	(	const Pose &	transform,
		const SpatialAcceleration &	acc_in )

Transform of a spatial acceleration from a coordinate frame A to another coordinate frame B. The mapping is performed using the adjoint \( Adj(X) \in R^{6 \times 6} \) of the given input transform \(X = (R,p) \in SE(3)\) as follows:

\[ \left(\begin{array}{cc} \dot{\omega} \\ \dot{v} \end{array}\right)_B = \left(\begin{array}{cc} R & 0 \\ \left[p\right]R & R \end{array}\right) \left(\begin{array}{cc} \dot{\omega} \\ \dot{v} \end{array}\right)_A \]

with

\[ \left[p\right] = \left(\begin{array}{ccc}0 & -p_z & p_y \\ p_z & 0 &-p_x \\ -p_y & p_x & 0\end{array}\right) \]

and
\( \dot{\omega} \in R^3\) - Angular acceleration
\( \dot{v} \in R^3\) - Linear acceleration
\( R \in SO(3)\) - Rotation matrix
\( p \in R^3\) - Translation vector

*According to: Lynch, K.M. and Park, F.C. 2017. Modern Robotics: Mechanics, Planning, and Control. page 100. Cambridge University Press, USA

Parameters

transform	Input transform as position and orientation of frame A expressed in frame B (not vice versa!)
acc_in	Input spatial acceleration, expressed in coordinate frame A

Returns

Spatial Acceleration in new coordinate frame B

operator*() [2/3]

Twist wbc::types::operator*	(	const Pose &	transform,
		const Twist &	twist_in )

Transform of a twist \( V = (\omega,v)^T \) from a coordinate frame A to another coordinate frame B. The mapping is performed using the adjoint \( Adj(X) \in R^{6 \times 6} \) of the given input transform \(X = (R,p) \in SE(3)\) as follows*:

\[ \left(\begin{array}{cc} \omega \\ v \end{array}\right)_B = \left(\begin{array}{cc} R & 0 \\ \left[p\right]R & R \end{array}\right) \left(\begin{array}{cc} \omega \\ v \end{array}\right)_A \]

with

\[ \left[p\right] = \left(\begin{array}{ccc}0 & -p_z & p_y \\ p_z & 0 &-p_x \\ -p_y & p_x & 0\end{array}\right) \]

and
\( \omega \in R^3\) - Angular velocity
\( v \in R^3\) - Linear velocity
\( R \in SO(3)\) - Rotation matrix
\( p \in R^3\) - Translation vector

*According to: Lynch, K.M. and Park, F.C. 2017. Modern Robotics: Mechanics, Planning, and Control. page 100. Cambridge University Press, USA

Parameters

transform	Input transform as position and orientation of frame A expressed in frame B (not vice versa!)
twist_in	Input twist, expressed in coordinate frame A

Returns

Twist in new coordinate frame B

operator*() [3/3]

Wrench wbc::types::operator*	(	const Pose &	transform,
		const Wrench &	wrench_in )

Transform of a wrench \( F = (m,f)^T \) from a coordinate frame A to another coordinate frame B. The mapping is performed using the co-adjoint \( Adj(X)^{-T} \in R^{6 \times 6} \) of the given input transform \(X = (R,p) \in SE(3)\) as follows*:

\[ \left(\begin{array}{cc} m \\ f \end{array}\right)_B = \left(\begin{array}{cc} R & \left[p\right]R \\ 0 & R \end{array}\right) \left(\begin{array}{cc} m \\ f \end{array}\right)_A \]

with

\[ \left[p\right] = \left(\begin{array}{ccc}0 & -p_z & p_y \\ p_z & 0 &-p_x \\ -p_y & p_x & 0\end{array}\right) \]

and
\( m \in R^3\) - Torque/moment
\( f \in R^3\) - Linear force
\( R \in SO(3)\) - Rotation matrix
\( p \in R^3\) - Translation vector

*According to: Lynch, K.M. and Park, F.C. 2017. Modern Robotics: Mechanics, Planning, and Control. page 110. Cambridge University Press, USA

Parameters

transform	Input transform as position and orientation of frame A expressed in frame B (not vice versa!)
wrench_in	Input twist, expressed in coordinate frame A

Returns

wrench in new coordinate frame B

operator-()

types::Twist wbc::types::operator-	(	const types::Pose &	a,
		const types::Pose &	b )