Polarity Reversal Method for Shape Control

Introduction

This chapter proposes a foundation to control shape of deformable machines consisting of actively deformable materials. If the problem is stated in inverse kinematics form, the required method is to control joint angles, in this case, curvatures, of arbitrary points to fulfill some condition. It is difficult to control every part of the body directly since the numbers of input is smaller than degrees of freedom of the machines.

Part III challenges control problem of gel robots. The problem was arranged into shape control problem and motion control problem and discuss each of them in chapter 7 and chapter 8 respectively.

In this chapter, a method to evolve simple shape of the gels into complex shape is studied. The experimental system goes back to the original one before part II temporally, to make the problem simple and to focus on deformation process itself. I apply spatially uniform electric fields to the beam-shaped gel. Only the polarity of the electric fields is altered.

This chapter was adapted from in part, by permission, M. Otake, Y. Kagami, Y. Kuniyoshi, M. Inaba, and H. Inoue, “Inverse Kinematics of Gel Robots made of Electro- Active Polymer Gel”, Proceedings of IEEE International Conference on Robotics and Automation, pp.3224–3229, 2002; M. Otake, Y. Nakamura, and H. Inoue, “Pattern Formation Theory for Electroactive Polymer Gel Robots”, Proceedings of IEEE International Conference on Robotics and Automation, pp.2782–2787, 2004; M. Otake, Y. Nakamura, M. Inaba, and H. Inoue. Wave-shape Pattern Control of Electroactive Polymer Gel Robots. Proceedings of the 9th International Symposium on Experimental Robotics, ID178, 2004.