Soft-amphibious robot using thin and soft McKibben actuator

摘要

This paper introduces a quadruped soft-amphibious robot using 4.0 mm diameter thin and soft McKibben actuator. The robot utilizes its leg and body bending mechanism to locomote. For each leg, three links of the actuators are arranged in parallel with fixed upper and bottom part. Then, four actuators are arranged in parallel and fixed with a thin plastic plate in between the actuators for the body motion. The elastic deformation of the plastic plate actuated by the actuators assist in the side-to-side motion of the robot mimicking the gait of the biological creature like lizard/salamander during walking motion. FEM simulation studies were performed in Marc Mentat <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">®</sup> to evaluate the bending behaviors and validated with an experimental test. Walking experiment was tested on a flat surface and on sand using two different gaits of trot and crawl gait. On the other hand, swimming experiment was tested inside water using only crawl gait. Different input pressure and frequency were varied to study the walking behavior. The robot successfully walks on a flat and 10° incline plane with a maximum speed of 0.056 m/s using trot gait and robust to move on sand and in water using the crawl gait at 0.041 m/s and 0.022 m/s, respectively.