Research And Design Of Hybrid Wing UAV System In Polar Sea Ice Monitoring

Since the 21st century,the Arctic environment is warming more conspicuously.Both the distribution range and the total amount of sea ice have decreased significantly.This undoubtedly affects the ice mass balance in the Arctic region,thereby destroying the normal ocean circulation pattern and affecting the global environment.Sea ice research has gradually become the focus of polar scientific research.In recent years,Chinese scientists have gradually deployed ice-based buoys on the Arctic sea ice to obtain fixed-point sea ice environmental data,but these traditional devices are unable to monitor sea ice parameters on a large scale.With the application and development of Unmanned Aerial Vehicle(UAV)technology in various industries,it is gradually becoming possible to use UAVs for environmental monitoring in polar expeditions.This subject is funded by the key research and development program of the Ministry of Science and Technology of the Ministry of Science and Technology of the"Polar Observation and Exploration Equipment Research and Development—Arctic Sea Ice Unmanned Ice Station"(grant number 2016YFC1400302)and the Shanxi Provincial Department of Science and Technology"Marine Small Aircraft Buoy Device Development"(grant number201803D121007).Design and develop a hybrid-wing UAV that can be equipped with temperature,humidity,atmospheric pressure,light intensity and image vision sensors to carry out real-time monitoring of polar sea ice and upper atmospheric environment.There are two types of hybrid-wing UAVs.Motors can be under tilt control or not.In this project,tilt-rotor UAVs are selected as the design object in order to achieve the tilting function of hybrid-wing UAVs and the ability of sea ice environmental monitoring.The mission profile of the hybrid-wing UAV is analyzed.The mission is divided into two important modes and a transition link.The two important modes refer to the quad-rotor flight mode and the fixed-wing flight mode.In this paper,the force analysis and dynamics modeling of the transition process of these two modes are carried out.The overall flight layout of the hybrid-wing UAV and the control scheme in the tilting mode are studied.This article selects and configures power modules such as motors,ESCs,and steering gears according to the power requirements of each part of the hybrid-wing UAV.At the same time,the identification and measurement experiments of the related unknown parameters in the dynamic model were carried out for the selected power configuration,including the measurement experiment of the rotor tension coefficient,the measurement experiment of the response characteristic of the motor and the steering gear.According to the requirements of the polar sea ice environment monitoring capability,this article selects the main control chip and various sensors and uses the Altium Designer hardware PCB design tool to design the circuits,mainly including the circuit of various sensors communication interface(SPI,I~2C,USART and etc.)connected with the main control chip and the peripheral circuit of each sensor chip.In addition,to facilitate the wiring and connection of the internal power supply compartment of the hybrid-wing UAV,this article separately designed a power adapter circuit board.At the same time,the MIC5332 power distribution circuit is designed inside the main controller,and the 3.3V power supply is divided into 4 functional areas to ensure that the power supply of each part of the main controller is not disturbed.The open-source flight control APM software is studied in this article,and the transplantation of the APM software on the designed hardware is completed which is by writing and modifying the hardware abstraction layer in the APM code.For the special flight mode of the hybrid-wing UAV,the relevant program is combined with the control scheme of this article.Due to the requirements of polar sea ice environmental monitoring,GY-39environmental observation module that integrates temperature,humidity,atmospheric pressure,and light intensity sensors and image transmission camera driver are added in the driver library of the APM code.The ice environment monitoring program of the application layer is programmed.Based on the design and completion of the software and hardware,the reliability test of the program and the hardware is carried out.First of all,the compiled results of the program are simulated through the APM SITL simulation function in the setting environment.The simulation results verify the reliable operation of the polar sea ice environment monitoring software.The flight log data recorded in the simulation is analyzed,the attitude angle changes within the range of fluctuation requirements of the designed hybrid-wing UAV Finally,the hybrid-wing UAV prototype was gradually tested from basic functions and fixed-point hovering functions,and completed the flight of the UAV finally.This verifies the reliability of software and hardware.The design of this subject still has some shortcomings in fully automated monitoring.This kind of Hybrid-wing UAVs requires operators to fly remotely.During the research period of this subject,an automated UAV take-off and landing buoy platform were also designed for small quadrotor UAVs.It relies on traditional ice-based buoy technology to provide an automated storage platform for UAVs.In the future,hybrid-wing UAVs can be designed and compatible with such buoy platforms to realize fully automated large-scale sea ice monitoring.