Departmental Papers (MEAM)

Document Type

Conference Paper

Subject Area


Date of this Version

May 2001


Copyright 2001 IEEE. Reprinted from Proceedings of the 2001 IEEE International Conference on Robotics and Automation (ICRA 2001) Volume 1, pages 157-162.
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We describe a framework for controlling a group of nonholonomic mobile robots equipped with range sensors. The vehicles are required to follow a prescribed trajectory while maintaining a desired formation. By using the leader-following approach, we formulate the formation control problem as a hybrid (mode switching) control system. We then develop a decision module that allows the robots to automatically switch between continuous-state control laws to achieve a desired formation shape. The stability properties of the closed-loop hybrid system are studied using Lyapunov theory. We do not use explicit communication between robots; instead we integrate optimal estimation techniques with nonlinear controllers. Simulation and experimental results verify the validity of our approach.



Date Posted: 19 November 2004

This document has been peer reviewed.