Abstract
This paper considers a systematic approach for motion planning and feedforward controldesign for a flexible cantilever actuated by piezoelectric macro-fiber composite (MFC)patches. For accurate feedforward tracking control, special attention has to be paid to theinherent nonlinear hysteresis and creep behavior of these actuators. In order to account forthese effects an appropriate compensator is applied which allows us to perform the trackingcontroller design on the basis of a linear infinite-dimensional model. A detailed analysisof the nonlinear actuator behavior as well as the compensator design and theoverall experimental validation is presented in the companion paper (Schröck et al 2011 Smart Mater. Struct. 20 015016). The governing equations of motion ofthe hysteresis and creep compensated cantilever are determined by means of theextended Hamilton’s principle. This allows us to consider the influence of thebonded patch actuators on the mechanical properties of the underlying beamstructure in a straightforward manner and results in a model with spatially varyingsystem parameters. For the solution of the motion planning and feedforwardcontrol problem a flatness-based methodology is proposed. In a first step, theinfinite-dimensional system of the MFC-actuated flexible cantilever is approximated by afinite-dimensional model, where all system variables, i.e. the states, input and output, canbe parameterized in terms of a so-called flat output. In a second step, it is shownby numerical simulations that these parameterizations converge with increasingsystem order of the finite-dimensional model such that the feedforward controlinput can be directly calculated in order to realize prescribed output trajectories.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call