ABSTRACT
The investigations according to this topic belong to a joint project between the TU Ilmenau, Piezo system Jena, and the Fraunhofer Gesellschaft IOF Jena. The work ran over a period of one year. The problem is represented as follows. Piezo stacks are characterised by great strengths and short re action times. If the actuators are accessed with step signals they produce a strong overshoot after the end of the intended movement. The shape of the overshoot depends on the overall system. This overshoot is very disturbing in the case of refining positioning tasks because the short acting times of the piezo actuators are more than compensated for waiting at fading away of the oscillation. How can the overshoot time or the overshoot itself be reduced without losing the favourable qualities of piezo stacks? Pure passive damping leads to
large time constants since it does not only per form against the overshoot but also against ta r get movement. An interesting idea is to apply the damping only after term ination of the movement task. Electrorheological and magnetorheological fluids are novel materials of special interest becau se they can modify their rheological qualities by an excitation.
