Candidate: Chris Fernandes
Advisor: B. Mishra

Nonholonomic Motion Planning : Algorithms and Software

1:30 p.m., Friday, July 23, 1993
12th floor conference room 719 Broadway


Robot motion planning with nonholonomic constraints has recently engaged the attention of roboticists, as its application in dexterous manipulation, mobile robots and space robotics has begun to be understood. Such constraints arise from two different sources - Rolling Constraints and Non-Integrable Conservation Laws. For instance, the kinematics of dexterous manipulation using hard fingers making contact on a hard object requires nonholonomic motion planning (NMP) in order to satisfy rolling constraint. On the other hand, the control of attitude of space platform-based manipulators using only the internal motion of their manipulator joints requires NMP, as a result of the law of conservation of angular momentum.

Recently some algorithms and their implementation in software have been created in order to understand, simulate and control nonholonomic systems. Currently most of the algorithms have been demonstrated in somewhat specialized applications. There is a great need for software that enables the researcher to quickly test algorithms on these simple systems and then experiment with potential generalizations.

In this thesis, we describe a software system that we have developed at NYU and the underlying principles and algorithms (the ``Basis algorithm''). The system runs on SGI Iris, is written in C with auxiliary tools from Unix, Mathematica, DASSL etc. We shall also describe how we have designed controllers for such example nonholonomic systems as unicyle, space station and space platform-mounted robot manipulator.

It is hoped that this thesis will be useful for the control engineers engaged in designing non-linear control systems, for roboticists studying dexterous manipulations, motion planning and space robotics and finally, for software engineers interested in building tools and applications for robotics.