Open AccessHybrid Pneumatic-Hydraulic Actuator with Adaptable Stiffness
Author(s) -
Ajike Emmanuel O.,
Blerjana Bino,
M. Surbil,
M. Badrieh,
S. Khasawneh
Publication year - 2020
Publication title -
international journal of recent technology and engineering
Language(s) - English
Resource type - Journals
ISSN - 2277-3878
DOI - 10.35940/ijrte.f7241.038620
Subject(s) - actuator , stiffness , pneumatic actuator , control theory (sociology) , hydraulic cylinder , hydraulic machinery , electro hydraulic actuator , robot , work (physics) , pid controller , hydraulic motor , artificial muscle , engineering , computer science , control engineering , mechanical engineering , control (management) , structural engineering , artificial intelligence , temperature control
This work presents a method to control the stiffness of a hybrid actuator. The resulting stiffness is required to meet the conditions of real life applications, such as human prosthetics, human-robot interaction, and delicate robot interaction. The hybrid actuator is basically a pneumatic-hydraulic muscle, which can operate simultaneously in both pneumatic and hydraulic modes. The main challenge in this work is to manage the switching between pneumatic and hydraulic modes. In pneumatic mode when a load is applied to the actuator, air in the tank is allowed to compress resulting in muscle extension. While in hydraulic mode, the fluid is pressurized and the resultant system stiffness is higher. In both cases, the McKibben muscle is full with hydraulic fluid. It has been shown that the performance of the actuator is mostly the same in terms of response and bandwidth in both modes of operation. The use of different types of controllers to improve the system performance is investigated. It is found that the parallel configuration combined with PID controller is the best solution for achieving the required muscle performance.