Attitude stabilization of quadruped walking robot

This paper deals with estimating the attitude of a walking quadruped robot in the presence of engine noise. Contrary to wheeled robots, legged robots are inherently supposed to work in uneven environment. Therefore estimating the attitude of walking legged robot becomes the utmost important factor in designing such machines in order to control them. We have used IMU as the prime sensor for stabilized attitude estimation. In fact accelerometer is used for roll/pitch observations in stationary/quasi-stationary state. But this data is not suitable unless pre-processing. This involves the pre-filtering and error factor determination for raw IMU data. Engine vibration effects are removed by low-pass filter and error-factor are calculated by least square fit to raw IMU data. Finally results of applying these simple techniques show the stability of attitude estimation on quadruped walking robot in real experiment.