Recursive newton euler inverse dynamics solver. More...

#include <chainidsolver_recursive_newton_euler.hpp>

Inheritance diagram for KDL::ChainIdSolver_RNE:

Public Member Functions
int	CartToJnt (const JntArray &q, const JntArray &q_dot, const JntArray &q_dotdot, const Wrenches &f_ext, JntArray &torques)
	ChainIdSolver_RNE (const Chain &chain, Vector grav)
virtual void	updateInternalDataStructures ()
	~ChainIdSolver_RNE ()
Private Attributes
std::vector< Twist >	a
Twist	ag
const Chain &	chain
std::vector< Wrench >	f
unsigned int	nj
unsigned int	ns
std::vector< Twist >	S
std::vector< Twist >	v
std::vector< Frame >	X

Detailed Description

Recursive newton euler inverse dynamics solver.

The algorithm implementation is based on the book "Rigid Body Dynamics Algorithms" of Roy Featherstone, 2008 (ISBN:978-0-387-74314-1) See page 96 for the pseudo-code.

It calculates the torques for the joints, given the motion of the joints (q,qdot,qdotdot), external forces on the segments (expressed in the segments reference frame) and the dynamical parameters of the segments.

Definition at line 40 of file chainidsolver_recursive_newton_euler.hpp.

Constructor & Destructor Documentation

KDL::ChainIdSolver_RNE::ChainIdSolver_RNE	(	const Chain &	chain,
		Vector	grav
	)

Constructor for the solver, it will allocate all the necessary memory

Parameters:

chain	The kinematic chain to calculate the inverse dynamics for, an internal copy will be made.
grav	The gravity vector to use during the calculation.

Definition at line 27 of file chainidsolver_recursive_newton_euler.cpp.

KDL::ChainIdSolver_RNE::~ChainIdSolver_RNE ( ) [inline]

Definition at line 48 of file chainidsolver_recursive_newton_euler.hpp.

Member Function Documentation

int KDL::ChainIdSolver_RNE::CartToJnt	(	const JntArray &	q,
		const JntArray &	q_dot,
		const JntArray &	q_dotdot,
		const Wrenches &	f_ext,
		JntArray &	torques
	)		`[virtual]`

Function to calculate from Cartesian forces to joint torques. Input parameters;

Parameters:

q	The current joint positions
q_dot	The current joint velocities
q_dotdot	The current joint accelerations
f_ext	The external forces (no gravity) on the segments Output parameters:
torques	the resulting torques for the joints

Implements KDL::ChainIdSolver.

Definition at line 44 of file chainidsolver_recursive_newton_euler.cpp.

void KDL::ChainIdSolver_RNE::updateInternalDataStructures ( ) [virtual]

Update the internal data structures. This is required if the number of segments or number of joints of a chain/tree have changed. This provides a single point of contact for solver memory allocations.

Implements KDL::SolverI.

Definition at line 34 of file chainidsolver_recursive_newton_euler.cpp.