Motion feedforward tuning for hysteretic piezo actuators

Piezo stepper actuators are used in many nanopositioning systems because of their high resolution, high stiffness and fast response, and their ability to position a mover over an infinite stroke by means of a motion reminiscent of walking. A major drawback of employing piezoelectric actuators is their hysteretic behaviour. The history dependence of hysteresis prevents the application of a trivial compensating feedforward controller for existing hysteresis models. The method presented in this Mikroniek article exploits a new hysteresis modelling approach that allows for a straightforward feedforward controller that can be manually tuned, reminiscent of industry-standard tuning approaches for mechanical feedforward components.