Research On Route Planning And Trajectory Control Of Attack Helicopter

Route planning and trajectory control system of the attack helicopter is studied in this dissertation. Divide the system into several sub-systems and study on the main techniques. The main contents are as follows:It discusses and simulates several problems of digital map technique in aviation: including random terrain, mountain simulation, fractal surface generation, by those we canget statistic data of the terrain. We can get the data not on the grid by fractal interpolationsurface. It discusses data storage format and the conception of threat model, which can addthe threat to digital map that can transform the threat avoidance to terrain avoidance.In the course of the design of trajectory optimization, we adopt the improved adaptive genetic algorithm. First, the route planning problem is converted into the restricted short-cut problem and Dijkstra algorithm is used to get the rough optimized trajectory which makes terrain avoidance and threat avoidance effectively. Then, the adaptive genetic algorithm is used to optimize the reference trajectory. The trajectory planning software is developed which runs credibly.This dissertation combines DYNAPATH algorithm with adapt-angle TF algorithm to create the three-dimension reference flight trajectory. This method can enhance attack aircraft survivability and increase strike effectiveness while reducing pilot workload.Because the model of helicopter is a highly coupled unstable nonlinear system, a group of nonlinear motion equations are established first, and then analyzed the infection of the couple of motion and the couple of control of the free helicopter. This work supplied the physics concept for the design the flight control system.In this dissertation the control loop of attitude angle and collective piston loop are separately. The controller is designed at two scales. And the simulation shows the uncoupling of three attitudes angle loop is achieved with dynamic inversion scheme. It also simulates and tests the robustness of dynamic inversion scheme.Adaptive neural network is discussed to compensate the inversion error resulted from inaccurate model of helicopter. By studying the BP network based on Lyapunov stability, we discuss the adaptive control law and design the neural network controller. The simulations show the controller could compensate inversion error effectively.Finally, the trajectory tracking controller based on CM AC and PID parallel control is designed, which is combined with attitude angle controller and complete whole flight controller system. To the reference flight trajectory, the controller has good tracking ability and satisfies precision request.