A safety service manipulator system: the reduction of harmful force by a controllable torque limiter

Robots working in human environment for personal service should have both safety and dexterity function. Since these two functions have characteristics that influence each other on an implementation process, it is necessary to treat them together in a system. In this paper, we propose a safety serve manipulator system (SSM) which has the potential to realize both the safety and dexterity simultaneously, and discuss on the effectiveness of slip motion that is one of the safety functions of the SSM in reduction of contact force. The SSM slip motion is realized by torque limiters located on the base. We confirm the effectiveness of the torque limiters in reduction of harmful force at various limit torque and improve the reduction efficiency by controlling the limit torque. These are confirmed through simulations and experiments.