Cards

Robotics Toolbox for Matlab
ans = 0 0.6000 -0.5000 0 -0.6000 0 0.4000 0 0.5000 -0.4000 0 0 m = 0 0.6000 -0.5000 0 -0.6000 0 0.4000 0 0.5000 -0.4000 0 0

0.1000 0.2000 0.3000 1.0000

0.1000 0.2000 0.3000 1.0000

m = 0 0.7000 -0.6000 0 -0.7000 0 0.5000 0 0.6000 -0.5000 0 0 0.1000 0.2000 0.3000 0

ans = 0.1000 0.2000 0.3000 0.5000 0.6000 0.7000

ans = 0.1

ans = 0.99875

(Release 8)Peter I. Corke
Peter.I.Corke@gmail.com http://www.petercorke.com

December 2008

c 2008 by Peter I. Corke.

3

1
Preface
1 Introduction
This, the eighth release of the Toolbox, represents nearly a decade of tinkering and a substantial level of maturity. This release is largely a maintenance one, tracking changes in Matlab/Simulink and the way Matlab now handles help and demos.There is also a change in licence, the toolbox is now released under LGPL. The Toolbox provides many functions that are useful in robotics including such things as kinematics, dynamics, and trajectory generation. The Toolbox is useful for simulation as well as analyzing results from experiments with real robots. The Toolbox is based on a very general method of representing the kinematics anddynamics of serial-link manipulators. These parameters are encapsulated in Matlab objects. Robot objects can be created by the user for any serial-link manipulator and a number of examples are provided for well know robots such as the Puma 560 and the Stanford arm. The Toolbox also provides functions for manipulating and converting between datatypes such as vectors, homogeneous transformations andunit-quaternions which are necessary to represent 3-dimensional position and orientation. The routines are written in a straightforward manner which allows for easy understanding, perhaps at the expense of computational efficiency. My guide in all of this work has been the book of Paul[1], now out of print, but which I grew up with. If you feel strongly about computational efficiency then you can alwaysrewrite the function to be more efficient, compile the M-file using the Matlab compiler, or create a MEX version.

1.1 What’s new
This release is primarily fixing issues caused by changes in Matlab and Simulink R2008a. • Simulink blockset and demos 1–6 all work with R2008a • Some additional robot models were contributed by Wynand Swart of Mega Robots CC: Fanuc AM120iB/10L, Motoman HP and S4 ABB2.8. • The toolbox is now released under the LGPL licence. • Some functions have disappeared: dyn, dh • Some functions have been redefined, beware: – The toolbox used to use roll/pitch/yaw angles as per the book by Paul[1] in which the rotations were: roll about Z, pitch about Y and yaw about X. This is different to the more common robot conventions today, and as used in the vehicular and aerospaceindustry in which roll is about X, pitch about Y and yaw about Z. The functions tr2rpy and rpy2tr have been changed accordingly.

1 INTRODUCTION

4

– The functions rotx, roty and rotz all used to return a 4 × 4 transform matrix. They now return a 3 × 3 rotation matrix. Use the functions trotx, troty and trotz instead if you want a 4 × 4 transform matrix. • Some functions have been added: –r2t, t2r, isvec, isrot. • HTML format documentation is provided in the directory htmldoc which was generated using the package m2html. This help is accessible through MATLAB’s inbuilt
help browser, but you can also point your browser at htmldoc/index.html.

All code is now under SVN control which should eliminate many of the versioning problems I had previously due to developing the code acrossmultiple computers. A first cut at a test suite has been developed to aid in pre-release testing.

1.2 Other toolboxes
Also of interest might be: • A python implementation of the toolbox. All core functionality is present including kinematics, dynamics, Jacobians, quaternions etc. It is based on the python numpy class. The main current limitation is the lack of good 3D graphics support but...