jacob0.m

Robot tool box - provides many functions that are useful in robotics including such things as kinem

%JACOB0 Compute manipulator Jacobian in world coordinates
%
%	J0 = JACOB0(ROBOT, Q)
%
% Returns a Jacobian matrix for the robot ROBOT in pose Q.
%
% The manipulator Jacobian matrix maps differential changes in joint space
% to differential Cartesian motion (world coord frame) of the end-effector.
% 		dX = J dQ
%
% For an n-axis manipulator the Jacobian is a 6 x n matrix.
%
% See also: JACOBN, DIFF2TR, TR2DIFF.


% Copyright (C) 1999-2008, by Peter I. Corke
%
% This file is part of The Robotics Toolbox for Matlab (RTB).
% 
% RTB is free software: you can redistribute it and/or modify
% it under the terms of the GNU Lesser General Public License as published by
% the Free Software Foundation, either version 3 of the License, or
% (at your option) any later version.
% 
% RTB 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 Lesser General Public License for more details.
% 
% You should have received a copy of the GNU Leser General Public License
% along with RTB.  If not, see <http://www.gnu.org/licenses/>.

function J0 = jacob0(robot, q)
	%
	%   dX_tn = Jn dq
	%
	Jn = jacobn(robot, q);	% Jacobian from joint to wrist space

	%
	%  convert to Jacobian in base coordinates
	%
	Tn = fkine(robot, q);	% end-effector transformation
	R = t2r(Tn);
	J0 = [R zeros(3,3); zeros(3,3) R] * Jn;