Evaluation of Ground Slipperiness During Collision Using MEMS Local Slip Sensor

In this paper, we propose a method to evaluate slipperiness of a place where a foot of a legged robot collides. This method will enable the robot to prevent a slip even if the slipperiness is unexpected, whereas conventional robots have no choice but to presume the slipperiness. We show a MEMS local slip sensor is applicable to not only static situations but also dynamic situations like collision. We tested the sensor by dropping it vertically against three types of surfaces which varied in slipperiness. The results show the three surfaces can be distinguished during the collision by monitoring the sensor response.