Design And Control Of 3-degree-of-freedom Helicopter Experimental System

As one of the key creations of aviation technology in the 20 th century,helicopter is widely applied to many occasions with the development of human lives.And the global market has shown an increased demand for helicopters,which brings opportunities and challenges to the helicopter's research.The helicopter system is a high-order,strongly coupled,multiple-input multiple-output(MIMO)nonlinear system,hence many scholars are devoted to studying its control theory and method.During the study of control theory and control method of the helicopter system,we usually need to simulate the flight attitude and demonstrate the proposed control method.However,the actual helicopter is so expensive that we cannot verify our control algorithm on it,which may easily lead to the loss of financial and material resources.Therefore,we need to study control algorithm through an experimental platform which has the same structure of actual helicopter.The three-degree-of-freedom(3-DOF)helicopter is one of the experimental platforms,which is an abstraction from the actual helicopter system.In this paper,we first deeply study the system development and motion control of the 3-DOF helicopter.Then,the LQR control scheme and the control strategy based on the unknown input observer are applied to the 3-DOF helicopter,respectively.Finally,the efficacy of the proposed method for the 3-DOF is verified by applying it to the self-designed 3-DOF helicopter system in our laboratory.The main works of this paper are summarized as:(1)The 3-DOF helicopter experimental platform is designed and fabricated.The system electric circuit is designed,and the experiment research is carried out.(2)The modeling and control for the 3-DOF helicopter system are studied in this paper.The mathematical model of the 3-DOF helicopter is first established via Euler-Lagrange equation,and then we design LQR control strategy for the system.Furthermore,one control method based on unknown input observer for the 3-DOF helicopter is proposed,and its robustness is analyzed in comparison with LQR control scheme.(3)The software and hardware of the 3-DOF helicopter are developed.One high-performance TMS320F28377 D dual-core processor is used to set its input and output and then achieve the real-time control;Human-computer interface is designed by C# language in Visual Studio software.(4)The efficacy and robustness of the proposed control method for the 3-DOF helicopter system is verified by experiment on a self-designed 3-DOF helicopter system in our laboratory.