Design, characterisation and control of TCN artificial muscles

Thumbnail Image
Publication date
Defense date
Journal Title
Journal ISSN
Volume Title
Google Scholar
Research Projects
Organizational Units
Journal Issue
Today there are several muscle weaknesses that hinder individuals from fully using their mobility. In attempts to solve these problems, several artificial muscles, so called actuators, have been invented to complement skeletal muscles. Yet, there is not a single actuator that covers all the characteristics of such muscles. In recent years, a new way of manufacturing actuators has made its way into the field. The actuators are manufactured by twisting and coiling silver coated nylon yarn and activated by sending a voltage through them. This thesis covers research on the design, characterisation and control of Twisted and Coiled Nylon (TCN) actuators. It explains the manufacturing process, including the yarn to use, the number of twists to perform for the thread to coil and how to handle the coiled thread. It also describes how to manufacture a longer actuator. The characterisation and control are studied through testing the actuators with a control program written in MATLAB and comparing their behaviour due to several PID parameters together with a bilinear compensation and displacement reference. The project also includes an introduction to a rigidifiable material where the actuators are applied to change the rigidity of a flexible material. In conclusion, the result of the study of the design, characterisation and control shows that the material used, Shieldex® 235/36 dtex 2-ply HCB, does not reach new heights in the research on TCN actuators due to its force-to-strain ratio being lower than the ratio of previously obtained actuators. The actuators can still be used in the rigidifiable material, which gives them a future chance.
Artificial muscles, TCN, Twists, Coils, Actuator, Displacement, Contraction, Relaxation, PID
Bibliographic citation