Performance of live muscle tissue as an in-vitro mechanical actuator

Developing creative solutions in mechanical actuation is an essential need for the rapidly progressing technological applications. Studies in the field are becoming more challenging due to increasing demands of lighter and smaller actuators with higher efficiency. This thesis introduces a new approach for the problem by considering live muscle tissue as an actuator for macro mechanical systems, thus investigates the in-vitro performance of muscles in a mechanical perspective. Muscle tissue is a kind of smart material and a perfect mechanical actuator with its compact architecture that integrates force and position sensors, power generating units and energy reserves within a single organ. Unlike most conventional mechanical or electromechanical actuators muscle tissue is able to adapt to changes in power needs, has adjustable mechanical impedance and uses a renewable energy source. Most of the research on the subject focuses on developing bio-actuators for micro pumps while few of them investigate macro scale bio-actuators. Former studies point to the significance of developing a robust control strategy in order to have an effective actuator. For this study performance parameters are chosen as controllability, service life and feasibility. A muscle testing apparatus is designed and manufactured for muscle characterization and control purposes. Mechanical response and fatigue behaviour of gastrocnemius muscle of Rana esculenta frog is characterized and various models are prepared accordingly. Models are used to test and improve control algorithms. As a result the effect of stimulation parameters on muscle mechanical output is determined similar to the studies presented in the literature. Control trials are carried out with a certain accuracy and muscle specimens remained functioning up to 36 hours. These outcomes reveal a general perspective of advantages and challenges in using muscle tissue as a bio-actuator and show that the muscle is a possible actuator in mechanical systems. The interdisciplinary approach yields a promising solution to certain mechanical actuation problems and opens up remarkable new possibilities in bio-mechatronics especially for medical field such as developing bio-mechatronic prostheses and robots.