Modelling and Control of a Worm-Like Micro Robot with Active Force Control Capability

Abstract

In this paper, a pneumatic worm-like micro robot with active force control (AFC) capability is modelled and simulated in a constrained environment (pipe). A mathematical model that represents the dynamic characteristics of the worm-like micro robot is first presented. Then, the dynamic response of the robot system subjected to different input excitations is investigated. A proportional-integral-derivative (PID) controller is applied to the micro robot system to follow the desired trajectory while an AFC controller is utilized to reject the unwanted disturbances which may be created due to frictional forces or fluid viscosity in the pipe. The control system is tuned so that an accurate trajectory tracking is possible. The performance of the control system under different types of disturbances is evaluated through a rigorous simulation study. The obtained results clearly demonstrate an effective trajectory tracking capability of the worm-like micro robot in spite of the negative effects of the external disturbances.