RANDOM EXPLORATION STRATEGY - A NEW PARADIGM IN ROBOTICS - A COMPARISON WITH DETERMINIST APPROACHES

This paper presents the latest results of a joint research project inv olving the Institute of Microengineering of the Swiss Federal Institut e of Technology (Switzerland) and the Industrial Automation Laboratory of the Lyon National Institute of Applied Sciences (France). This pro ject consists in the implementation of a robotic assembly method for c hamferless parts by using a very fast parallel robot called DELTA. The paper recalls the main features of the system in order to focus on th e experimental evaluation of different search strategies employed to a bsorb misalignment between pieces, paying particular attention to the comparison of the mean search time of random and deterministic traject ories (such as random, Lissajous' and spiral trajectories) as a functi on of the clearance of parts. The experimental results obtained in thi s work show a better performance of the random strategy and stress the benefits of adopting a stochastic approach to design and implement op en-loop control strategies for robotic assembly processes.