Friction hysteresis compensation using phase correction of periodic trajectories

This paper presents a heuristic, signal-based approach to compensate time delay-like effects caused by friction hysteresis in a novel kind of valve actuator. It works by exploiting a-priori knowledge about (and the periodicity of) the desired trajectory, under the premise that an existing feedforward control already tracks the desired trajectory, apart from the mentioned time delay effect. However, the emphasis of this contribution is put on experimental results obtained with a test stand in order to substantiate the effectiveness of the simplistic compensating technique that was already described in earlier works. The hysteresis loop is modelled and simulated to match the measurements, though no model is needed by the compensation algorithm.