Twisted and coiled polymer muscles (TCPMs) show promise to function as artificial muscles, because of their lightweight, low cost, large contraction, and respectively low hysteresis. A TCPM contracts when it is heated and extends when it is cooled. Different modeling and controll
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Twisted and coiled polymer muscles (TCPMs) show promise to function as artificial muscles, because of their lightweight, low cost, large contraction, and respectively low hysteresis. A TCPM contracts when it is heated and extends when it is cooled. Different modeling and controlling techniques have been implemented. \cite{VanDerWeijde_2019} implemented a self-sensing model that does not need large apparatus for measurements of force and deflection. The goal of this thesis is to design a force controller that works with this model. Parameter estimation of the self-sensing model is done. The fit of the model is not high enough for control. A first order black-box model is estimated and used instead. A P and PI controller is simulated and tested on the setup. The force oscillates around the reference value. This is because the actual model is of order 2. A D-action needs to be added to dampen the oscillations. The integral action reduces the max to min and vice versa input behavior. The model parameter differs for each TCPM. The controller parameters have to be adjusted for each TCPM. This is impractical in large-scale applications. Further research can be done into using model-free controllers.