An extraction method of environmental surface profile using planar end-effectors

It is very important for robots working in unknown environment to recognize surface profile of the environment. This paper presents an extraction method of environmental surface profile based on environmental modes. Contact condition between a planar end-effector and the environment is also determined by using active motion which is named "groping motion" of the end-effector. The extraction method utilizes discrete Fourier transform (DFT) matrices as matrices transforming into environmental modes. The proposed method can be applied to a planar end-effector whose shape is an arbitrary polygon. Moreover, a compliance controller for attitude of a planar end-effector with 3 supporting points is proposed to realize stable contact motion with unknown environment. The validity of the proposed method is shown by the experimental results.