Research On Indoor Navigation And Control Of Quadrotor Based On Motion Capture System

In recent years,with the development of the new materials,MEMS technology and flight control technology,the small multi-rotor unmanned aerial vehicles(UAV)have been developed rapidly.Multi-rotor unmanned aerial vehicles have many advantages,such as simple structure,flexible control and vertical take-off and landing.Meanwhile,with its good maneuverability,excellent hover and low-speed flight performance,UAV has been paid more and more attentions,both in the military and civil field.In this paper,quadrotor is taken as the research object to study its modeling and control methods.Aming at the GPS information in the indoor environment cannot be abtained,and conventional airborne sensors have low accuracy and are susceptible to external interference,in order to improve the accuracy of the quadrotor control algorithm,the paper introduces the motion capture system,designs the navigation control system and built the test platform of quadrotor.Firstly,the navigation system of multi-rotor UAV is designed.The operation mechanism of the motion capture system is analyzed and researched,and the acquisition algorithm of the attitude information of multi-rotor UAV in the motion capture system is designed.The integrated navigation algorithm of the motion capture system and the inertial navigation system is studied.The experimental results show the feasibility of the proposed attitude algorithm and the correctness of the integrated navigation algorithm.Based on the VS 2008 development tool,the multi-rotor UAV ground station software system was designed,and the information was sent to the multi-rotor unmanned aerial vehicle(UAV)in real time via the serial port to complete the multi-rotor unmanned aerial vehicle test platform.Secondly,the quadrotor is chosen as the research object in the paper,and the fundamental principles of quadrotor are analyzed according to the structure of the quadrotor.The force and torque are analyzed according to Newton-Euler method,and the nonlinear dynamic model of the quadrotor are completed,and then the model is simplified based on reasonable assumptions.Thirdly,the simplified nonlinear dynamic model is linearized,and the LQR control is used for the linearized model,and the integral backstepping method is used for the simplified nonlinear model.Using the algorithms above,the attitude loop and position loop controller of the quadrotor is designed.The experiments of fixed-point hover,trajectory tracking and waypoint tracking are verified by Matlab / Simulink simulation.The simulation results show the effectiveness of the algorithms.Finally,combining the software of the flight control system and the hardware of the quadrotor,through the hover and waypoint flight experiments,the experimental results show that the designed controller can control the quadrotor in the target state well,and has good stability and tracking.