Optimum design and comparison of four soft reinforced actuators by Taguchi experimental design method

In this paper, four soft reinforced actuators are studied and their performance is compared. The soft actuators, because of their ability to match their shape with unknown environment, could be utilized in medical instruments such as rehabilitation devices, grippers, manipulators and bio-mimic hand. Here, the considered actuators are included a single elastomer channel wrapped with fiber reinforcements and an inextensible layer. Four actuators with half-circular and rectangular geometry are discussed. Two actuators have constant cross section and others have variable cross section. To study their performance they are modeled in Abaqus software. Also, a prototype of the soft actuator is manufactured and the numerical results are validated by the experiment results. Moreover, for studying the effect of each parameter and their interactions and finding the optimum design of the actuators the Taguchi method is used with a set of experiments. To this end, L27 array experiments are designed and each experiment is performed by finite element analysis in Abaqus. Then, the performance of each actuator is discussed and compared with each other and the optimum values of the parameters are determined. Results show the rectangular actuator has a more range of motion in comparison to half-circular one.