Development and Evaluation of An Attitude Measuring System that uses Acceleration Information of Walking for Biped Robots

Abstract

Biped walking causes translational acceleration and vibration on the torso where an attitude sensor system is usually implemented. The accuracy of measurement tends to be low because of those bad influences. We propose a method of attitude estimation that takes translational acceleration into account. Planned translational acceleration is derived from generated walking pattern, and subtracted from the output of the accelerometers, so that the effect of acceleration caused by robot motion is cancelled when the direction of gravity acceleration is estimated. An attitude measuring system which consists of 3 fiber optic gyroscopic sensors and 3 servo accelerometers was developed. The system was attached on a full size humanoid HRP-2, and the proposed method was implemented. The performance of the proposed method was evaluated during normal walking of HRP-2.