Design of a robust active fuzzy PDC anti-vibration controller for the gloved-hand system

Abstract

The prolonged use of the vibrating hand-held tools can cause discomfort, muscle fatigue and ergonomic injuries to the users which are known as hand-arm vibration syndrome (HAVS). The undesired vibration decreases the tool performance and the user productivity. Therefore it is very important to design a vibration suppression tool that can isolate or suppress the vibration transmission to the worker’s hand to protect them from HAVS. This work is carried out to design a vibration control approach that can be applied to the anti-vibration gloves to reduce the vibration transmission from the vibrating tool to the users so that it can keep the vibration level within the healthy caution zone which is less than 2:5 m=s2 for 8 hours exposure time. While the anti-vibration glove which includes viscoelastic materials is used as the passive vibration control approach, for the active vibration control we need to produce an actuation signal to cancel the vibration by using active elements along with the sensors and controller. Therefore, in this work first, an active model of the glove-hand system is considered and then by obtaining the mathematical model of the system, a fuzzy parallel distributed compensation (PDC) controller is designed in a way that it can perform well for different users with different hand masses. The capability and reliability of the proposed controller are evaluated through simulations and then the results are compared with the other active vibration control techniques including proportional integral derivative (PID) controller and active force controller (AFC). The simulation results show the excellent performance of the designed controller over the other types of controllers and its significant capability in reducing the transmitted vibration to the user’s hand.