Improved performance in temperature and speed of TCP artificial Muscles for Soft Wearables Robots by length modification

Abstract Artificial muscles provide a unique solution for wearable rehabilitation robots (WRRs) because they are compliant, compact, and lightweight. Twisted coiled polymer actuators (TCPs) artificial from thermally activated fibres. They present high power density, linearity, stress strain compared to other muscles. Nevertheless, as TCPs require heat start, their main barrier widespread use in WRRs slow reaction times the temperatures reach. Previous studies have analysed different parameters, like fibre material, diameter, various cooling systems, improve TCP frequency response working temperature. length of actuator has not been explored possible parameter enhance actuation performance this regard.

 This work focuses on studying behaviour with lengths how temperature can be improved using primary parameter, critical robots. First, characterisation was performed. Then, method response, based offsets long implemented validated chirp signal. The experimental results show that mechanical characteristics similar regardless actuator’s length. reached 10 % 0.16 W/cm. However, electrothermal properties changed needed increase higher when enlarged. Therefore, an improvement required found, able reduce same response. Regarding technique speed actuator, it by 0.0006 Hz each mm applied offset. Hence, displacement increased linearly elongated.