| The rapid development of science and technology has brought a huge impact on the traditional agricultural industry.In recent years,with the development of drone technology,farms have generally begun to use agricultural plant protection machines for agricultural crops.However,many farms have large areas and heavy workloads.The use of multi-rotor drones is not efficient in many operations due to the load.The fixed-wing flight speed is fast,and it is not suitable for plant protection aircraft.So experts and scholars gradually began to study the autogyro plant protection aircraft,because the autogyro aircraft has simple structure,low cost,high safety,and is a low-altitude,low-speed aircraft,which has natural advantages in agricultural plant protection aircraft.This paper conducts research work under this demand.The research content includes the modification of the autogyro,the establishment of a complete mathematical model,steady-state analysis,vertical and horizontal manipulation analysis,modification-based control strategy design,and two-degree-of-freedom PID based on improved PSO algorithm Controller design,finally designed a complete flight control software and ground station system,set up semi-physical simulation experiments in Matlab and Flight Gear.This article first introduces the sub-structure of a civil autogyro.The three-dimensional structure diagram is obtained by using a three-dimensional scanner.The control structure is modified on the basis of manual driving.According to the control structure,it is divided into rotor control modification,throttle opening control modification,and vertical Tail control modification,brake system modification,and the design of the fixed frame for installing the steering gear,the steering gear installation position,the throttle gate valve and the brake motor device,lay the foundation for the subsequent modification control.Subsequently,this paper established the various moment coordinate systems required for modeling,analyzed the rotation characteristics of the unpowered rotor based on aerodynamics,established corresponding models according to its structural composition and flight dynamics of each structure,and unified the moments through the coordinate system Converted to the body coordinate system,the kinematics equation of the rotorcraft is obtained.On the basis of mathematical modeling,the longitudinal and longitudinal stability of the autogyro is studied,and combined with the modification plan of the autogyro,the longitudinal and longitudinal control characteristics of the autogyro are comprehensively analyzed,and finally a control scheme corresponding to the control structure is designed.Due to the complexity of the control,the main lift rotor cannot directly control the speed,response lag and other characteristics.This paper uses a two-degree-of-freedom PID controller and a multi-PID control structure to adjust the response speed and robustness separately.In parameter tuning,the improved PSO algorithm can be used to quickly tune the optimal three PID control parameters and speed up the system response.The simulation results show that the two-degree-of-freedom PID controller based on the improved PSO algorithm has a good control effect.Finally,the development of the rotorcraft flight control system and the construction of the semi-physical simulation are introduced.The software and hardware components of the flight control system,the design of the ground station,etc.are introduced in detail.Then,in order to verify its effectiveness,the semi-physical simulation is built using MATLAB and Flight Gear software.The physical simulation platform verifies the level flight,climb and circular motion of the rotorcraft,and monitors the throttle opening change,pitch angle change,airspeed change,roll angle change,and height change of the rotorcraft.The unmanned autorotor is verified based on the simulation results.The effectiveness and feasibility of aircraft flight control. |
