To perform tasks such as hold an object with a constant force, the reliable control of an ionic electroactive polymer
actuator is essential. The composite under research is an IPMC actuator with electrodes composed of nanoporous carbon
and membrane made of ionic polymer. Compared to traditional platinum electrodes, these novel electrodes do not crack
in clusters and have highly controllable properties which preserve even when the actuator is deformed. So far, there are
no reports on the dynamic force response of this composite. We present the first attempts of testing the force dynamics
of an IPMC with nanoporous carbon electrodes under open- and closed-loop controls. As many attempts have been
focused on the sensorless force control of ionic electroactive polymers, we first investigate the uncompensated dynamics
of the actuator, then use the direct inverse model to obtain the desired tracking performance. We also aim to identify the
conditions, under which the actuator is suitable for sensorless control. Furthermore, we improve the tracking ability of
the actuator using a feedback controller where the force sensor data is available and incorporate a feedforward controller
into the feedback control system. Based on the experiments, the resulting effects on the tracking performance are
observed.
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