Design and development of a humanoid with Soft 3D-deformable sensor flesh and automatic recoverable mechanical overload protection mechanism

In order for robots to be able to assist humans at a very close distance, robots should allow contacts occurred at many places and deal with them. For realizing such functions, robots should have whole-body soft sensor exterior for preparing contacts against almost every body parts since it is difficult to limit where to be touched from humans. Although several groups have developed humanoid type robots which have soft tactile sensors, most of them detects distributed 1-axis forces and that is not sufficient when the robot and a human have contacts very closely. In addition to that, there is no consideration in the previous studies about humans´ movement during close contact with the robots. In order to solve these problems, we have newly developed a humanoid with soft 3D-deformable sensor flesh and automatic recoverable mechanical overload protection mechanism. Soft 3D-deformable sensors are implemented by molding the infrared light receiving devices into the urethane cube and by detecting the changes of the output voltage of the devices during the deformation. On the other hand, automatic recoverable mechanical overload protection mechanism is implemented by small mechanical torque limiters and monitoring system for embedded potentiometers in the torque limiters. Also detail implementation of the embedded electric system and the overall software structure is described in this paper.