Model Aircraft Use The Codec With Electronic Speed Governor

As aeromodelling technology developing and wide used in more and more fields, the aeromodelling system design have great engineering and market value.This paper focused on two part of aeromodelling: the one is PCM coder and decoder based on FPGA and the other is electronic speed controller based MCU, which is author's major work during working in a Xi'an model design house.First, this paper introduced the PCM coding and PPM coding, and analyzed the difference between of them in aeromodelling. Based on the analyzing of the original PPM coding, import the PCM coding which compatible with original machine. Through the PCM coding will improve the transmitter and receiver's veracity. During the code design, we add some especial code to the code stream, to solve the interference in the same frequency. At last we give the debug result use the coding module and decode moduleSecond, study the electronic speed controller of power system. Aim at the senseless brushless DC motor have great merits, such as low noise, high precision and low cost, this paper analyze the common methods of sensorless control ,back-EMF method is used in this paper, PWM modulate mode, and start method, expatiate the key technology of this controller involved. Last base on AVR MCU design the hardware, use assemble language design the control software.Finally, author makes demo board for the PCM coding and decoding and electronic speed controller, and use it do the real experimentation. The experiment suggests that system can work properly. At the end of this paper analyze the deficiency of the system, and point out the target of the further work.