Hiroaki Yamaguchi - 13 Sep 2010 - 12.00 @ Aula Magna
Speaker: Hiroaki Yamaguchi, Aoyama Gakuin University, Japan
Time and Location: Monday 13 September 2010, 12:00 (noon), Aula Magna
Title: Control of A New Type of Undulatory Robotic Locomotor: A Trident Steering Walker
Abstract. We would like to introduce and describe an entirely new type of undulatory robotic locomotor which is referred to as a "trident steering walker." The undulatory robotic locomotor is a nonholonomic mechanical system which consists of an equilateral triangular base, three joints, three links and four steering systems. The equilateral triangular base has a steering system at its center of mass. At each apex of the base is a joint which connects the base and a link. The link has a steering system at its midpoint. The undulatory robotic locomotor transforms driving of its three joints into its movement by operating its four steering systems. This means that the locomotor makes undulatory locomotion in which periodical changes in its own shape are transformed into its net displacement. It is well known that snakes move by undulatory locomotion. The trident steering walker is designed so that its kinematical equation can be converted into a chained form. Especially, virtu!
all mechanical elements are defined to make such conversion possible in a mathematical framework, differential geometry. We believe this is the very first attempt that a mechanism of an undulatory robotic locomotor is designed in such a manner as to satisfy conditions of the conversion of its kinematical equation into chained form. Based on chained form, we derive a path following feedback control law which causes the locomotor to follow any path whose curvature is two times differentiable. The validity of the mechanical design of the trident steering walker, the conversion of its kinematical equation into a chained form, and the path following feedback control law has been verified by simulation and experimental results. In particular, we demonstrate the effectiveness of the control method by showing videos of a garage entry operation of the trident steering walker.
Hiroaki Yamaguchi is Associate Professor at the Department of Integrated Information Technology, Aoyama Gakuin University