Twist Controlling Study Of Cantilever Beam Based On Piezoelectric Fiber Composites

At present, civil and military fields have put forward higher requests on aircrafts, which ask for good performance in various environments (height and Mach number, etc.) or a variety of missions (take-off and landing, hover, maneuvering, attack, etc.). Therefore, morphing aircraft technology is needed. Using the intelligent material or driver, aircraft can change its shape according to the varying flight environment and different flight missions, so the aircraft can always keep the optimal flight condition. Torsional deformation of the wings is the main deformational way of morphing aircraft, while the control of the wing’s torsional deformation is one of the difficulties that must be solved. Based on this background, a shrinkage ratio model of the wing-cantilever beam is chosen as the study object in this paper. The torsional control problem of the beam is studied based on the piezoelectric fiber composite MFC as the driverIn this paper, the main body of the object-flexible cantilever beam consists of resin-based glass fiber rib and skin, and the driver of torsional deformation is 45° polarized piezoelectric fiber composites MFC. The piezoelectric cantilever beam system has hysteresis nonlinearity and nonlinear creep properties, at the same time exists residual oscillation problem and model unknown problem due to electromechanical coupling and multi-body modeling. These factors above increase the difficulty of modeling and control of piezoelectric cantilever beam.According to the characteristics of piezoelectric cantilever beam system, The modeling and torsional control strategy is proposed in this paper. First, aiming at the hysteresis nonlinear property,improved PI model is established, and the system is linearized through the way of static inverse compensation; To avoid the problem of mechanism modeling, Prony algorithm is adopt to identify the transfer function of the system based on the step test; By directly using Prony identification parameter, the multimodal input shaper is designed to restrain vibration caused by command signal; In addition, aiming at the creep property and the influence of external interference, closed loop controller is designed. By combining the inverse compensation controller based on improved PI model, the multimodal input shaper, PID controller and Fuzzy controller, Fuzzy-PID-IS controller is designed for piezoelectric cantilever beam torsional positioning control.Based on the identified transfer function, numerical simulation experiment is carried out in Matlab/Simulink platform. Multimodal input shaper, PID controller, PID-IS controller and Fuzzy-PID-IS controller are simulated respectively. In addition, controlling performance is analyzed in detail. Experimental system is designed for piezoelectric cantilever beam’s twist control based on the software development platform of LabVIEW, and the control algorithm Proposed is applied in the hardware system. Experimental results show that through the inverse compensation control, static sine tracking error can be controlled under 14%, and the multimodal input shaper can effectively inhibit the vibration excited by command signal. Furthermore, Fuzzy-PID-IS controller can improve the control performance effectively on many aspects, including response speed, steady-state error, suppress interference, and so on.