Immediate Generation of Jump-and-Hit Motions by a Pneumatic Humanoid Robot Using a Lookup Table of Learned Dynamics

Abstract

This letter focuses on the jump-and-hit motion of a humanoid robot, wherein a robot instantaneously jumps forward and hits a flying ball in the air, similar to how human players behave in volleyball games. We propose a Immediate Motion generation using a Lookup table of learned dynamics (IMoLo) for generating the motions of a pneumatic humanoid robot. To test this method, we developed a humanoid robot called “Liberobot” with eight joints applying structure-integrated pneumatic cable cylinders. Using simulations, the prediction errors of the robot hand positions during the jump-and-hit motions measured via nonlinear interpolation when using IMoLo was smaller than without it in cases having a small number of training trials. In the experiments, the robot jumped and hit the flying ball 16 times out of 20 trials using the proposed motion generation method. The results indicate that a pneumatic humanoid robot using IMoLo can instantaneously perform dynamic whole-body motions, such as jump-and-hit motions, with a changing target within a specified time. Our humanoid robot is the first pneumatic humanoid robot capable of executing such dynamic motions.