Position tracking control of mass spring damper system with time-varying coefficients

In robotics, to ensure safe physical interactions between robots and environment for protecting actuators from being damaged by abrupt dynamics changes, compliance strategies are often preferred to be used to make their dynamic process to be more soft by following some natural features observed from humans. Mass-spring-damper (MSD) system is frequently encountered in many compliant robotics systems as a basic architecture. The actuator(s) of robots can be designed based on the form of MSD in order to achieve desired compliant properties. The conventional MSD model is with constant/static coefficients and has appeared in most compliant robots. However, in numerous application scenarios, the coefficients associated with MSD are time variant, making the traditional control strategies (e.g., PID control) hard to deal with. This paper propose a novel control approach for tracking control of MSD model with time-varying coefficients. Simulation results illustrate efficiency of the proposed method.