Application Design Of Four-rotor Aircraft In Marine Environment Monitoring

China is a big maritime country,and ocean transportation plays an important role in national production.Therefore,in the 13 th Five-Year Plan,the government has proposed to focus on developing marine strategies.This article takes this opportunity to develop an four-rotor aircraft applied in marine environmental monitoring.The innovation of the aircraft designed in this paper is to use the small flexibility of the aircraft to monitor the environment by using a variety of sensors for monitoring the marine environment.Lo Ra wireless transmission technology is used to communicate with the upper and lower machines.The FPV camera is used to collect information from the ship and marine sector to achieve long-distance monitoring of the marine environment.Because the marine environment is relatively bad and changeable,it is important for the aircraft to respond quickly to the changes of poor enviroment.This paper uses advanced fuzzy self-adaptive PID control theory to improve the stability of the aircraft and the quick response of the aircraft.Finally,the collected environmental data is displayed in the Lab VIEW PC software.The main research work of this paper mainly includes:(1)This thesis studies the structure and flight principle of the aircraft from the perspective of dynamics,establishes the dynamic equation,and analyze the conversion between the space coordinate system and the body coordinate system,and to solve the control system problems of the four inputs control numbers and the six state output numbers.Because the vibration of the four motors and the body of the aircraft will cause noise interference to the accelerometer of the attitude sensor MPU9250,in order to promote the integration of the accelerometer and the gyroscope,the Kalman filter algorithm is used to eliminate the cumulative error of the gyroscope and decrease the error of the attitude angle.(2)The hardware part selects STM32F405 as the main control chip.The author designs the flight control core board independently,and the brushless motor electronic speed control driver,and designs the PCBLayout circuit board with Altium Designer software.The PPM encoding analysis of the 2.4G encoded data packet of the remote controller.(3)For the bad weather of the sea surface,the balance control algorithm of the aircraft is very important.In this thesis,the PID control of the aircraft and the fuzzy adaptive PID are theoretically analyzed to verify the problems of the classical PID control,and the advantages of the fuzzy adaptive PID to quickly adjust the attitude of the aircraft.The attitude and position control of the aircraft is controlled by double closed loop,and the simulated data waveforms are compared and analyzed through the MATLAB/Simulink platform.(4)The study uses software to read data about the temperature,humidity,air quality(PM2.5,PM10),toxic gas,to analyze the working principles of the 5.8G video module and the way of communication.The paper uses software flowing chart to give detailed description,and send the collected data of marine environment back to the surface data station by wireless data transmitting system.The study design a host computer software to display the received sensor data in the dashboard.(5)For the data monitored by the marine environment of the aircraft,use Lab VIEW to design a PC software to display the received sensor data in the dashboard,which is convenient for users to monitor the changes of marine environment data more intuitively.