src/cdlbt/kinematics.c File Reference

#include <math.h>
#include <syslog.h>
#include <libconfig.h>
#include <gsl/gsl_blas.h>
#include <gsl/gsl_math.h>
#include <gsl/gsl_matrix.h>
#include <gsl/gsl_vector.h>
#include <barrett/cdlbt/kinematics.h>
#include <barrett/cdlbt/gsl.h>

Functions
int	bt_kinematics_create (struct bt_kinematics **kinptr, config_setting_t *kinconfig, int ndofs)
int	bt_kinematics_destroy (struct bt_kinematics *kin)
int	bt_kinematics_eval (struct bt_kinematics *kin, const gsl_vector *jposition, const gsl_vector *jvelocity)
int	bt_kinematics_eval_jacobian (struct bt_kinematics *kin, int jlimit, gsl_vector *point, gsl_matrix *jac)
Private functions
Copyright 2009-2014 Barrett Technology <support@barrett.com> This file is part of libbarrett. This version of libbarrett is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. This version of libbarrett is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this version of libbarrett. If not, see <http://www.gnu.org/licenses/>. Barrett Technology Inc. 73 Chapel Street Newton, MA 02458

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Detailed Description

Implementation of bt_kinematics, a simple forward kinematics library for single-chain revolute robots.

Author:

Christopher Dellin

Date:

2008-2009

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Function Documentation

int bt_kinematics_create	(	struct bt_kinematics **	kinptr,
		config_setting_t *	kinconfig,
		int	ndofs
	)

Create a bt_kinematics object from a given configuration.

This function creates a new kinematics object, reading the DH parameters and toolplate information from the configuration given by kinconfig. Currently, the number of moving links (ndofs) is also passed, and the creating fails if the number of moving links read from the configuration file does not match the expected number.

Parameters:

[out]	kinptr	The bt_kinematics object on success, or 0 on failure
[in]	kinconfig	Kinematics configuration, from libconfig
[in]	ndofs	Expected number of moving links

Return values:

0

Success

int bt_kinematics_destroy

(

struct bt_kinematics *

kin

)

Destroy a bt_kinematics object.

This function destroys a bt_kinematics object created by bt_kinematics_create().

Parameters:

[in]

kin

bt_kinematics object to destroy

Return values:

0

Success

int bt_kinematics_eval	(	struct bt_kinematics *	kin,
		const gsl_vector *	jposition,
		const gsl_vector *	jvelocity
	)

Evaluate all link transforms, including the toolplate jacobian.

This function is used in a control loop to update all link transform matrices (and associated matrix and vector views) given a vector of joint positions and velocities.

Parameters:

[in]	kin	bt_kinematics object
[in]	jposition	Joint position vector
[in]	jvelocity	Joint velocity vector

Return values:

0

Success

int bt_kinematics_eval_jacobian	(	struct bt_kinematics *	kin,
		int	jlimit,
		gsl_vector *	point,
		gsl_matrix *	jac
	)

Evalulate the Jacobian matrix at a paticular point on a particular link.

This function evaluates the Jacobian matrix for a given point on a given moving link.

Parameters:

[in]	kin	bt_kinematics object
[in]	jlimit	The number of the moving link on which the point lies, (ndofs for the toolplate)
[in]	point	The point at which the Jacobian should be calculate, in world coordinates
[out]	jac	The Jacobian matrix into which to calculate; it should be an alread-allocated 6-N matrix.

Return values:

0

Success