Trajectory Tracking Control Of Quad-rotor Under Interference Conditions

With the improvement of manufacturing level related to quad-rotor,the development of microprocessor technology,energy storage technology and the progress of inertial measurement unit,quad-rotor has been widely used and developed in civil and military fields by virtue of its advantages of miniaturization,intelligence,flexible flight and easy maintenance.At the same time,the working flight environment of quad-rotor is more and more complex,so how to improve the trajectory tracking control quality of quad-rotor under interference conditions is the key to achieve stable flight of quad-rotor under interference conditions.In the disturbance environment,adaptive adjustment of the controller to improve the disturbance estimation and suppression ability of the controller can improve the control quality of the quad-rotor trajectory tracking to a certain extent.Therefore,this paper will focus on the trajectory tracking control of quad-rotor under interference conditions,mainly including the following aspects:（1）The quad-rotor model and the quad-rotor dynamic model under interference conditions are established.Firstly,the hardware composition and flight principle of quad-rotor are described.After establishing the earth coordinate system and the body coordinate system,the transformation relationship between the two coordinate systems was found,and the basic hypothesis of the quad-rotor model was given,and the dynamics model of the quad-rotor was deduced.Secondly,the variable mass disturbance and wind disturbance in the working flight environment of the quad-rotor are analyzed and derived,and the corresponding disturbance formula is introduced into the dynamics model of the quad-rotor to obtain the dynamic model of the variable mass quad-rotor and the dynamics model of the quad-rotor under the conditions of wind disturbance.（2）Analyze the trajectory tracking control quality of the active disturbance rejection control system of quad-rotor with different parameters.Firstly,the tracking differentiator,extended state observer and linear error feedback control rate of active disturbance rejection controller are theoretically analyzed and deduced,and the general form of active disturbance rejection controller is obtained.Based on four rotor dynamic model of quad-rotor,the design of each channel（ADRC）,and set up quad-rotor since the immunity control system,each of the parameters in the system to estimate the disturbance rejection capability theory,the influence of the completed quad-rotor under different observer bandwidth expansion since the immunity control trajectory tracking control simulation experiment.Experiments verify that the tracking control quality of active disturbance rejection control system varies greatly under different extended observer bandwidths.Therefore,online tuning of extended observer bandwidths is needed to improve the tracking control quality of quad-rotor.（3）Aiming at the problem that variable mass disturbance will affect the trajectory tracking control of quad-rotor,fuzzy-ADRC controller is designed.Based on active disturbance rejection controller,fuzzy controller is used to adjust the bandwidth of the extended observer online.Fuzzy control rules are defined,a new extended observer formula is established,and the stability of fuzzy controller and active disturbance rejection controller is theoretically deduced and analyzed,and the convergence of the proposed algorithm is proved.Finally,the flight simulation experiment of fuzzy-ADRC trajectory tracking control system of variable mass quad-rotor is completed.Experimental results show that fuzzy-ADRC trajectory tracking control system has faster response speed and smaller maximum trajectory tracking error.（4）BP-ADRC controller is designed to solve the problem of trajectory tracking control of quad-rotor under wind disturbance.Based on the active disturbance rejection controller,BP neural network was designed to adjust the gain of the expanded observer,and the formula of the gain of the expanded observer was given.The BP-ADRC trajectory tracking control system of quad-rotor was designed and built,and the flight simulation experiment of trajectory tracking control was carried out under the condition of wind disturbance.The experimental results show that the BP-ADRC trajectory tracking control system has good control ability,and the trajectory tracking control time is shorter and the error is smaller.