Research On Consistency Control Of Quadrotor Aircraft

With the development of society,the application of UAV is becoming more and more extensive.Q uadrotor is a kind of the most common UAVs,and it has the advantages of simple structure,no runway,and vertical takeoff.Although a single quadrotor has many advantages,there are still problems,such as limited load,small scope of work and so on.The emergence of these problems limits the application of the quadrotor.So we study of multiple quadrotors to improve work efficiency and solve the task which the single quadrotor can't accomplish.Firstly,Flight principle and dynamics model of quadrotor were studied.Secondly,we controlled attitude,height,hovering,autonomous take-off and landing and designed ground station for a single quadrotor.Finally,the problem of synchronization and formation consistency of multiple quadrotors were studied,and the specific contents are listed as follows.(1)When studying the dynamic model of quadrotor,the three-dimensional motion in space was decomposed into translational and rotational motion.According to the force and motion,a simplified quadrotor dynamic model was established under ignoring air resistance.The simulation control system was built in MATLAB/simulink to simulate the movement mode of the quadrotor,and the simulation results show the validity of the model.(2)In the research of single quadrotor,we first designed the indoor positioning system,and the target recognition algorithm based on color features.External image processing equipment was used to identify and calculate the position of quadrotor.In addition,the image processing equipment and the communication system between the quadrotors were built to transmit the position coordinates information.Then,we designed the attitude fusion algorithm based on quaternion,and double loop PID attitude algorithm were proposed to control attitude.We use ultrasonic to get height information,and the height of double closed-loop control algorithm was proposed to control fixed height hover and variable height hover.Besides,combined with the image recognition and positioning system,the compensation function of the PID control algorithm was proposed to realize the hover and switching hover.O n the basis of attitude control and height control,quadrotor autonomous takeoff and landing control strategy was proposed too.Finally,the proposed algorithms were verified one by one.(3)The problem of two quadrotors synchronous control was studied.Synchronous control model was built,and the synchronous control algorithm was designed.Moreover,we structure the Leader-Follower control system with two quadrotors,and use the actual flight test to verify the effectiveness of the algorithm.(4)The problem of multiple quadrotors formation consistency was studied.At a specified distance error and fixed topology,combining the multi-agent consensus algorithm,the quadrotor formation consistency control algorithm was proposed.We use MATLAB software to simulate a consistency system of the quadrotors with one leader and four followers.The simulation results show the effectiveness of the consensus algorithm.