Implementation Of UAV Control System Based On The Architecture Of DSP/FPGA

UAV has a great value in aspects of military and civilian. In recent years, the rapid development of semiconductor industry provides a good embedded solution for the flight control system, the core of UAV. DSP has good features of high-speed and high-precision in computing, and FPGA is easy to implement logic resources and peripheral expansion. The flight control system designed based on them has broad application prospects.This paper develops a flight control platform which is designed based on DSP and FPGA architecture. DSP is used to run data processing, algorithm implementation and management of peripheral. FPGA is used to provide serial peripherals expansion for DSP. Besides, it also details to describe the design of auxiliary circuit of FPGA and DSP Control CARD interface with its applications. PICOBLAZE IP core, SPI and 15 UART modules are implemented in FPGA chip, which realize a stable and high-speed communication between external devices and the DSP.As the direct executive body of UAV system, precision and flexibility of the servo controller determines the flight control system's performance. This system is mainly designed for 70LCX Series Servo, the control object. A full-bridge PWM motor driver chip DRV8402 adapts the PWM signal generated from DSP to matching power, then it is directly used to drive servo operation. To constitute a feedback control, servo parameters are also needed to be sampled by the A/D module in DSP chip. The data is collected after the standard voltage signal conditioning and read by process run in DSP to participate in the process of control algorithm operation.The end of the paper describes the theory of helicopter's mechanism model and PID controller, and driver programs are implemented in the DSP, including PWM signal generation, A/D data acquisition and data exchange between FPGA expansion and DSP. It completes the software and hardware experiment that digital closed-loop control system required. Discussions listed above lays a good foundation for the follow-up testing and further work.