38 Int. J. Mechatronics and Manufacturing Systems, Vol. 6, No. 1, 2013 Copyright © 2013 Inderscience Enterprises Ltd. A forming algorithm and its position estimation for triangle-based robot formation Tatsuya Kato*, Keigo Watanabe and Shoichi Maeyama Department of Intelligent Mechanical Systems, Division of Industrial Innovation Sciences, Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushima-naka, Kita-ku, Okayama 700-8530, Japan E-mail: t.kato@usm.sys.okayama-u.ac.jp E-mail: watanabe@sys.okayama-u.ac.jp E-mail: maeyama@sys.okayama-u.ac.jp *Corresponding author Maki K. Habib Mechanical Engineering Department, School of Sciences and Engineering, The American University in Cairo, AUC Avenue, P.O. Box 74, New Cairo 11835, Egypt E-mail: maki@aucegypt.edu Abstract: Robot formation is useful for multi-robot systems. However, when robots have different ability in function, their positions significantly affect the working efficiency. Therefore, it needs to assign the position of heterogeneous robots in formation. This paper describes an imaginary equilateral triangle (IET) algorithm that can allocate each robot on a desired position in a swarm without using global coordinate. The IET algorithm forms the swarm by making some equilateral triangles, one of which consists of one pair of two robots to be a reference base and one single robot to be an apex. Through some simulation experiments, the convergence of some formations based on the IET algorithm is confirmed and the convergence time is also evaluated. Furthermore, we test the translational and rotational movements in formation. Alternatively, the method needs a system that obtains the ID and relative position of the robots. This paper describes how to construct the measurement system using wireless communication and ultrasonic sound, and evaluate it through some simulation experiments. Keywords: multi robot system; robot formation; heterogeneous robots; swarm robot; ultrasonic sensor; wireless communication. Reference to this paper should be made as follows: Kato, T., Watanabe, K., Maeyama, S. and Habib, M.K. (2013) ‘A forming algorithm and its position estimation for triangle-based robot formation’, Int. J. Mechatronics and Manufacturing Systems, Vol. 6, No. 1, pp.38–56.