The Design And Realization Of A Digital Servo Controller For Launch Vehicle Based On DSP

Digital servo controller for launch vehicle control system is an important component of the rocket, which is used to achieve an key terminal of data bus network and composes a position feedback control loop with hydraulic actuator. The main task is to receive real-time location instruction calculated by computer in rocket through data bus and drive electro-hydraulic servo valve move using the PID algorithm and power amplifier circuit to control actuator cylinder linear motion, which finally leads to vehicle engine in the designed location and achieve control of the rocket's posture and stability. This paper focuses on research and design of the digital servo controller, including servo control and the bus terminal.According to the requirement of the embedded servo controller as a remote intelligent terminal of 1553B bus, the module of TMS320F2812, a digital signal processor (DSP) chip from TI company, is selected as the core processor unit. The hardware design is based on functional power module, servo control and data bus communication module and analog/digital convert module. Using AD7862 and MUX switch chips extend a total of 22-channel analog acquisition. Servo motor of the valve is driven using the AD390 chip and current-parallel negative-feedback amplifier circuit. The 1553B data bus communication, receiving data and sending data, is completed by BU-65170 chip of Data Device Corporation (DDC).About software design, selecting the integrated development environment CCS2.0 of Texas Instrument Corporation and programming code of servo control and 1553B data bus communication using C language. The programming codes achieve servo control process in 1ms cycle and 1553B bus intelligent terminal functions. Controller may response 1553B mode code, including self-test, self-reset and time synchronization. In addition, this paper also discusses the design of build-in test about servo controller. Compared with analog circuit one, digital servo controller with 1553B bus function has good adaption and modular design, as well as the advantages of a certain intelligence, which is the direction of development for rocket's servo controller. The design method of electro-hydraulic servo controller in this paper provides a way for domestic rocket's servo system design in future.