Design of Friction Compensation Filter in Frequency Domain by Spectral Envelope for Sensor-less Force Control

This paper proposes a friction compensation method in the frequency domain using a spectrum envelope. Friction compensation in mechanism is essential to improve the operability for haptics, the nonlinearity makes it difficult to realize high accuracy. This paper introduces the Cepstral analysis, and proposes a model-less compensation method using spectral envelopes. By using the Cepstral analysis, the feature of the system friction force can be treated as the gain characteristics of bode diagram. The proposed filter design using a spectral envelope is applied to the reaction force observer. The effectiveness of the proposal was confirmed by experiments using a linear motor.