Stable reflex-based walking of forelimbs of a bio-inspired quadruped robot-modeled cheetah

Abstract

In contrast to the high movement adaptability of quadruped animals in many environmental conditions, it is hard for conventional quadruped robots to operate in complex environment conditions. We investigate the adaptability of animals' musculo-skeletal systems, by building a bio-inspired quadruped robot named "Pneupard" which duplicates a feline musculo-skeletal system. In this study, we built Pneupard's forelimb which has 14 active muscles, 4 passive muscles and 8 degrees of freedom (DOF). We propose sole reflex-based control and verify its effectiveness by conducting walking experiments, in which the robot performed stable walking with a twodimensional restriction.

Realization of three-dimensional walking of a cheetah-modeled bio-inspired quadruped robot

“…It has 4 links and 9 muscles in each forelimb and 3 links and 7 muscles in each hindlimb. In our previous studies [7], [8], we focused on only hindlimbs or forelimbs and proposed a sole reflexbased control system. First, we built a Pneupard's hindlimbs and successfully made the robot walk on a treadmill [7].…”

“…First, we built a Pneupard's hindlimbs and successfully made the robot walk on a treadmill [7]. Next, we built Pneupard's forelimbs and succeeded to make the robot walk on a treadmill [8].…”

“…Through the rigid spine, the legs are interacting with each other, but we do not apply any extrinsic communication among legs: only physical interaction through the rigid spine. In our previous work [7], [8], the robot only had hindlimbs or forelimbs, therefore, the movement was almost in the sagittal plane. By combining the legs, the robot can now move in 3D, which makes its locomotion more challenging.…”

“…By combining the legs, the robot can now move in 3D, which makes its locomotion more challenging. We basically apply the same reflex-based control as [7] and [8], and show how it works through real experiments. Owaki et al [9] adopted similar control to successfully make a simple quadruped robot walk.…”