Development of a velocity and contact force-based mechanical safety device for service robots

Safety is one of the most important issues in service robots. We have proposed a velocity-based mechanical safety device for service robots. The safety device is attached to each drive-shaft of service robots. If the device detects an unexpected high angular velocity of the drive-shaft, the device stops the robot. In this paper, in order to further improve human safety, we propose a velocity and contact force-based mechanical safety device for service robots. The safety device is also attached to each drive-shaft of service robots. The new device stops the robot, if the device detects an unexpected high angular velocity of the drive-shaft or an unexpected large contact force between the robot and the environments (e.g. humans). The device can work even if the robot´s controller does not work, because the device consists of only passive mechanical components without actuators, controllers, or batteries. Firstly, we describe the characteristics of the new safety device. Secondly, we explain the structure and mechanism of the new safety device. Thirdly, we show a wheeled robot equipped with the new safety device which we developed. Finally, we verify the effectiveness of the new safety device by experiments.