rttgdemo.m

Robotics TOOLBOX The Toolbox provides many functions that are useful in robotics including such thi

% Copyright (C) 1993-2002, by Peter I. Corke
% $Log: rttgdemo.m,v $
% Revision 1.3  2002/04/02 12:26:49  pic
% Handle figures better, control echo at end of each script.
% Fix bug in calling ctraj.
%
% Revision 1.2  2002/04/01 11:47:18  pic
% General cleanup of code: help comments, see also, copyright, remnant dh/dyn
% references, clarification of functions.
%
% $Revision: 1.3 $
%*****************************trajectory****************************************
figure(2)
echo on
% The path will move the robot from its zero angle pose to the upright (or 
% READY) pose.
%
% First create a time vector, completing the motion in 2 seconds with a
% sample interval of 56ms.
    t = [0:.056:2];
pause % hit any key to continue
%
% A polynomial trajectory between the 2 poses is computed using jtraj()
%
    q = jtraj(qz, qr, t);
pause % hit any key to continue

%
% For this particular trajectory most of the motion is done by joints 2 and 3,
% and this can be conveniently plotted using standard MATLAB operations
    subplot(2,1,1)
    plot(t,q(:,2))
    title('Theta')
    xlabel('Time (s)');
    ylabel('Joint 2 (rad)')
    subplot(2,1,2)
    plot(t,q(:,3))
    xlabel('Time (s)');
    ylabel('Joint 3 (rad)')


    pause % hit any key to continue
%
% We can also look at the velocity and acceleration profiles.  We could 
% differentiate the angle trajectory using diff(), but more accurate results 
% can be obtained by requesting that jtraj() return angular velocity and 
% acceleration as follows
    [q,qd,qdd] = jtraj(qz, qr, t);
%
%  which can then be plotted as before

    subplot(2,1,1)
    plot(t,qd(:,2))
    title('Velocity')
    xlabel('Time (s)');
    ylabel('Joint 2 vel (rad/s)')
    subplot(2,1,2)
    plot(t,qd(:,3))
    xlabel('Time (s)');
    ylabel('Joint 3 vel (rad/s)')
pause(2)
% and the joint acceleration profiles
    subplot(2,1,1)
    plot(t,qdd(:,2))
    title('Acceleration')
    xlabel('Time (s)');
    ylabel('Joint 2 accel (rad/s2)')
    subplot(2,1,2)
    plot(t,qdd(:,3))
    xlabel('Time (s)');
    ylabel('Joint 3 accel (rad/s2)')
pause % any key to continue
echo off