Actuator Arrangement and Motion Form of Vertebrate Leg

Abstract

We clarified the relationship between the arrangement and the motion of actuators (muscles), corresponding to the drive system for vertebrate legs, including those of the human, planning to apply our results to robot drive systems. To do so, we anatomically compared muscular arrangements of plantigrade animals, such as humans and gorillas, and unguligrade animals, such as horses and deers,and amphibious jumping vertebrates, such as frogs. We analytically clarified distinctive functional features at the link end constituted by the differences in muscular arrangement by a robotic engineering method with a 2-joint link model. We found that muscular arrangement features are greatly involved in output and stiffness at the link end and reflect features of motion in each group of animals. We studied feasible application of the drive system by verifying its effects in muscular arrangement to make the drive system practical.