Robot motion evaluation of a musculoskeletal robot by simulation in terms of energy flow in the kinetic chain

摘要

Recently, many partner robots which coexist with humans in the human environment have been developed and actively investigated all over the world. For such robots, safety as well as motion ability similar to humans is important in order not to damage humans and the surrounding environment. It is essential for safety of a robot whose actuator power is low. A musculoskeletal robot with a humanlike muscle-skeleton structure gives one possibility for safety. The musculoskeletal robot comprises redundant and relatively low-power actuators (i.e., artificial muscle actuators). Accordingly, only a single actuator cannot produce dangerous power. An important issue in such a robot is how to effectively produce kinetic energy required to perform a desired motion by using the coordination of multiple actuators. Robot motion is caused by energy flow between each body of the robot through the kinetic chain. Therefore, in order to achieve the high motion performance of a robot with low-power actuators, it is important that mechanical energy generated by actuators is appropriately distributed to each body of the robot according to a desired motion. In this paper, we evaluated robot motion using simulation in terms of energy flow in the kinetic chain. The results indicate that the high motion performance of a robot with low-power actuators can be achieved by planning proper motion trajectories.