Attitude Calculation And Control Of Agricultural Multi-axis UAV

The flight altitude of agricultural multi-axis(UAV)is lower,and the flight attitude will be easily disturbed by the surface air flow,so the time allowed for adjusting attitude is very short.Thus the real-time and accuracy of attitude data is extremely important for agricultural UAV.In this paper,in order to enhance the real-time and accuracy of attitude calculation results,the problem of attitude calculation became the main issue.The attitude calculation system of a four-axis UAV with X structure was set in this project.The dynamic model of a small four-axis UAV was esTab.lished.For the convenience of the study,the air resistance was so small that it was ignored,so that the solving process would be simplified.For suppressing the Motion angle of UAV,a Multi DOF experimental bench was designed.Then the four-axis UAV was fixed on the experimental bench,and the data of the attitude sensor was acquired.According to the collected data,the characteristics of the signals ware analyzed.Comparing complementary filter and Kalman filter,a new method for attitude Calculating based on the pre-Kalman filter was presented.Finally,compared with the PID control algorithm and the fuzzy PID control algorithm,the control system based on PID combined with FUZZY-PID ware designed.The experimental results show that the update time was about 1ms in advance compared with the improved complementary filtering fusion algorithm.Comparing with Kalman filtering fusion algorithm,the operation cycle was reduced by 0.246 ms.The error was reduced by 2°.Compared with other algorithms,the proposed algorithm has a better real-time performance,which can provide more accurate attitude feedback for flight control system.The simulation results show that the time of regulation is less than 0.2S,and the overshoot is less than 7%.It shows that the PID combined with FUZZY-PID control system is better.