Recursive newton euler inverse dynamics solver. More...

#include <treeidsolver_recursive_newton_euler.hpp>

Inheritance diagram for KDL::TreeIdSolver_RNE:

Classes
struct	Entry
struct	JntEntry
Public Member Functions
int	CartToJnt (const JntArray &q, const JntArray &q_dot, const JntArray &q_dotdot, const Wrenches &f_ext, JntArray &torques)
int	CartToJnt (const std::vector< double > &q, const std::vector< double > &q_dot, const std::vector< double > &q_dotdot, const Wrenches &f_ext, JntArray &torques)
	TreeIdSolver_RNE (const Tree &tree, Vector grav)
	~TreeIdSolver_RNE ()
Private Attributes
Twist	ag
	indexed by joint name
std::map< std::string, Entry >	db
std::map< std::string, JntEntry >	jntdb
	indexed by segment name
std::string	root_name
Tree	tree

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 39 of file treeidsolver_recursive_newton_euler.hpp.

Constructor & Destructor Documentation

KDL::TreeIdSolver_RNE::TreeIdSolver_RNE	(	const Tree &	tree,
		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 36 of file treeidsolver_recursive_newton_euler.cpp.

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

Definition at line 47 of file treeidsolver_recursive_newton_euler.hpp.

Member Function Documentation

int KDL::TreeIdSolver_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

these are not RT safe... maps are dangerous because might create element inadvertently

Implements KDL::TreeIdSolver.

Definition at line 187 of file treeidsolver_recursive_newton_euler.cpp.

int KDL::TreeIdSolver_RNE::CartToJnt	(	const std::vector< double > &	q,
		const std::vector< double > &	q_dot,
		const std::vector< double > &	q_dotdot,
		const Wrenches &	f_ext,
		JntArray &	torques
	)		`[virtual]`