Modeling, position and viscosity control of intelligent pneumatic actuator

Abstract

Intelligent pneumatic actuator (IPA) is a new developed actuator which integrates actuator, and others new features such as microcontroller and various micro sensors. This type of actuator has the capability to communicate with computer to give better control, higher position and force accuracy. In prior to that, several experimental setup for the stiffness and viscosity control had been done using conventional PI controller. The previous experimental results showed that these control algorithms were feasible for the real IPA system. In this project, the work focuses more on the reverse engineering method, which is from existing real IPA system which had been developed by Dr. Ahmad ‘Athif Mohd Faudzi, to simulation analysis for the validation of other controllers. The objectives of this project are to develop a simulation model to represent the real IPA system, and design other controllers to be applied in this developed simulation model. For the simulation model, nonlinear mathematical modeling based on fundamental physical derivation is presented. Open-loop and closed-loop simulation works are done to confirm this model based on this derivation. Closed-loop IPA system is divided into two main control algorithms, which are position control for position tracking control and viscosity control for force tracking control. Several controllers which are related to the fuzzy logic are designed and applied to these control algorithms. The simulation results from these controllers are then validated and compared with result of using conventional PI controller. The comparison is made by analyzing their performances based on control theory. Lastly, due to the nonlinearities problem exist in nonlinear mathematical model, linearization method is proposed to obtain a new linear model to ease the controller design and analysis. For the future research, it is recommended to implement all the proposed controllers to the real-time IPA system.