Research On Control Technology Of Industrial Multi-rotor UAV

Compared with consumer-grade drones,industrial-grade multi-rotor UAVs have the characteristics of heavy weight,large windward area and high cost.Therefore,there are more stringent requirements for its flight control technology.This paper focued on the three aspects of flight control stability,anti-interference and intelligence.It used classical PID,ADRC,Smith predictor and visual feedback to optimize the flight control system of existing industrial-grade multi-rotor.Firstly,the multi-rotor object was modeled and analyzed.The Newton-Eulerian equation was used to derive the mathematical equation of the multi-rotor rigid body model.The motor response module was used to identify the power unit module,and the SimMechanics-based multi-rotor physical model was built for the subsequent controller design.The setting of parameters,system identification laid the foundation of the platform.Summarized the application and defects of Euler angle in flight control system,and used quaternion instead of Euler angle to describe multi-rotor flight attitude.Aiming at the multi-rotor motion characteristics,the attitude of tilt and torsion separation was used to plan the attitude error,optimize the rotation path,and realized the decoupling control of the attitude channel.Then the linear model of multi-rotor attitude channel was linearized,the attitude controller based on cascade PID was designed,the multi-rotor pitch channel transfer function was identified,and the classical PID theory was used to analyze the tuning significance of cascade PID)parameters.The ADRC technology was used to make up for the shortage of the classic PID.The tracking differentiator was used to perform the angle loop command planning and the angular velocity loop feedforward control.The extended state observer was used to observe the total disturbance of the system to realize the dynamic compensation of the disturbance.The Smith predictor was used to solve the disturbance compensation lag problem,and finally the attitude controller was optimized.The attitude test proved that the attitude controller has excellent stability and anti-interference performance.Finally,the position controller based on visual feedback was designed to realize the image preprocessing,target recognition and tracking,pose estimation and other functions of the visual feedback module.The cascade PID controller of multi-rotor horizontal position and altitude was designed.And the reliability of the vision algorithm and the position controller was verified by the fixed-point landing experiment,which made the flight control system more intelligent.