Dynamic modeling and robust control of an L-shaped microrobot based on fast trilayer polypyrrole-bending actuators

In this article, analytical dynamic model derivation and robust position control of a microrobot based on fast trilayer polypyrrole-bending actuators employing quantitative feedback theory is presented. The conjugated polymer actuators based on polypyrrole can be employed to achieve microscale precision positioning, having a wide range of application including biomimetic robots and biomedical devices. There has been extensive research on modeling the electrochemical dynamics of polypyrrole bending actuators. However, the mechanical dynamics modeling of actuator remains to be unexplored. In this article, we first develop a proper mechanical dynamics model for the fast-conducting polymer actuators that matches well with the existing experimental results and then extend it to a microrobot. In the controlling part, the robust control quantitative feedback theory will be used to control the microrobot with variable tip loading. The numerical simulation results show that the quantitative feedback theory controller has consistent and robust-tracking performance.