Design And Implementation Of Control Platform Of Small Aircraft Based On Embedded System And Machine Vision

With the rapid development of control technology and control devices, moreand more research institutions and enterprises are gradually studied UAV. UAV incivilian areas have gradually have more applications. The project comes from"985" construction projects, while developing vision technology and embeddedtechnology, the ultimate form of automatic four-rotor flying platform can be usedfor teaching demonstration and flight control principle of verification.Although there are some domestic universities and research institutes in thestudy of four-rotor aircraft, but the vast majority of research is related to thecontrol method of the aircraft, or to build aircraft controllers. The final product isnot capable of automatic flight, need people to control. And in the field of flightcontrollers, the country has some of the companies can produce superior products.Therefore, the project avoided the research of aircraft controllers, directly use theexisting products, develop peripheral control of the aircraft. Namely the use ofsensors embedded in the feedback loop to build the platform, instead of humanmanipulation, enabling the aircraft automatic flight.The entire project consists of a camera, an ultrasonic sensor, a MEMSgyroscope, a PC, an ARM development board, a microcontroller developmentboard and a four-rotor aircraft constituted. Arranged in the ceiling camera willcapture the image of the area where the aircraft, after the image processing toidentify the aircraft in the plane of spatial position and orientation. The ultrasonicsensor is fixed on a plane to measure the vertical height of the aircraft, theinclined plane causes the ultrasonic sensor when tilted, the measured data is notthe vertical height of the plane. The MEMS gyroscope is used to detect the tiltangle of the aircraft. Vertical height can be calculated according to the data of thetilt angle and ultrasonic sensor.Each platform project a clear division of tasks. The PC is responsible forimage acquisition and processing, and the ultrasonic sensor and gyro datacollection is also included, then the PC calculates the position and attitude of theaircraft, i.e.,(x, y, z, θ). The PC send data to the ARM via WIFI, The ARMreferences control strategy and path planning to calculate the value of the control,which is passed to the microcontroller, The microcontroller output PWMwaveform to control aircraft in three-dimensional space in accordance with theautomatic flight path planning. The mechanical structure of the aircraft were modified. Completed theexperiment with the help of people. Finally, collected the aircraft’s flight data andanalyzed the flight data.