Research On Key Technology Of Automatic Carrier Landing For Unmanned Helicopter

Unmanned helicopter is the best option of the carrier-based aircraft, it has the advantage of: vertical takeoff and landing, hover, perform tasks at low altitude/low-speed and so on.However, due to the technical limitations, only a minority of carrier-based unmanned helicopter is to be used. Paper studies the key technology in the process of landing, providies reference and a new control ideas for unmanned helicopter automatic landing.Paper takes unmanned helicopter as the controlled object, automatic landing as engineering problems, focuses on the modern control methods to solve the key technology.Studies the research status of carrier-based unmanned helicopter and the key technology;Proposes an automatic landing strategy and some mathematical models; Proposes an explicit model-following H_∞loop-shaping algorithms based on multi-objective optimization, and designs a posturing control law; According to highly segmented strategy, designs the reference trajectory of return admission, improves the basic ADRC to design a position control law; Studies the deck motion forecast and compensation technology, a real-time forecast algorithm is proposed; Studies a dynamic decoupling control to inhibiting aft flow;Finally, carries out the semi-physical simulation for the designed policy and algorithms.Main innovative points in this paper are listed below:1.In order to solve the problem of automatic landing difficult, the overall structure of autonomous landing system and a unmanned helicopter autonomous landing strategy is proposed.The strategy include three stages that Return approach,Hover, Quick landing.2.In order to solve the strong coupling problem and robustness requirements, an explicit model-following H_∞loop-shaping algorithms based on improved multi-objective optimization is proposed. Based on explicit model-following control, H_∞loop shaping algorithm is introduced. An improved multi-objective genetic algorithm is presented to determine parameters of the weighting function, simulated annealing algorithm and an improved niche selection technology is introduced to improve the local search ability and enhance the diversity of population. The results show: The proposed algorithm improves the efficiency of the optimization algorithm, effectively suppress the coupling of the channels, enhances the robustness of the system3. In order to solve the problem of high-precision trajectory tracking, an active disturbance rejection control(ADRC) based on improved Vague is proposed. Observes the first disturbed state quantity rather than the control quantity, removes the integration part toimprove the dynamic response. While definiting the parameters of Non-linear combination in ADRC, an improved Vague similarity metric theory is proposed, reasoning rules are designed on the basis of dual domains and similarity calculation function is improved. The results show:The improved algorithm has high tracking accuracy and dynamic response.4. Aiming at the safety of trajectory, a basic trajectory design method based on height segmented strategy is proposed, thus the UH can enter into glide path and not falling into Radar blind area.5. In order to solve the problem that the landing opportunity is difficult to accurately determined, a kind of improved LSM-AIC-AR(n) based on the limited memory method is proposed. The concept of “break period” and the constraints of landing is proposed; When capturing " break period ", combines time series method and limited memory method to achieve real-time recursive prediction. The results show: The deck motion prediction algorithm can accurately projecties 5s.