Semantics of tasks and motions of robots -multi-mode control as a bridge between tasks and motions-

The purpose of our research is to establish a method to facilitate programming of robot's tasks in uncertain environments. First, philosophical consideration is given on 'tasks' and 'motions.' They are terms referring to the same things from different viewpoints. Tasks are related to human's intentions or values while motions are to physics. Motions are the realization of the tasks depending on the given environments. To link tasks and motions, the concept of multiple sensorimotor modes is proposed. A mode is defined as a specified relation between the sensory information and the robot motion, with a terminal condition. The modes are used to describe the tasks as well as to command the robot. We implemented some modes for a robot with a force sensor as functions in the C language and made programs for tasks of clearing tableware and extracting pegs using the modes. The experiments successfully demonstrated the applicability of multi-mode control to tasks in uncertain environments.