| This paper mainly completes the design and implementation of an embedded software for electromechanical servo control on a certain type of rocket.The closed-loop control function and 1553 B bus communication function are realized to meet the needs of the servo system.This paper decomposes the requirement of servo system for embed ded software,and puts forward the functional requirements of closed-loop control,digital communication,CAN bus online upgrade program and CAN bus online binding parameters,which provide the technical input conditions for the preliminary design of software.The architecture of software is designed,the target environment and real-time requirements of software operation are analyzed,the development environment of software operation is selected,and the resources needed for software operation are allocated.In order to ensure the correctness of the closed-loop control function of position,speed and current and improve the control accuracy,a full-digital simulation model and control algorithm of servo system are built,and a pure digital simulation is carried out.Through simulation analysis and verification,the influence of adding back EMF compensation to current closed-loop control on the control accuracy of each loop is analyzed and verified.Finally,it is concluded that the back EMF compensation can greatly improve the control accuracy of the current closed-loop,as well as the accuracy of the position and speed closed-loop.The software is designed and coded in detail.The initialization function of servo control software is designed.The software solidifies the entrance address into BOOT.In the initialization process,the software determines the start mode by judging the external start state of the external pins,then initializes the global variables,allocates the space,and finally enters the main function to execute the user’s initialization process.In the main function,the following operations are performed to initialize the running kernel of the DSP and initialize the user’s initialization process.External device,initialization and start w atchdog,initialization of 1553 B bus controller,ensure that the software has the correct environment configuration needed for software operation after initialization is completed;design the timing of reading and writing Bu65170 of DSP,ensure the correct operation of the software to the off-chip programmable chip,provide guarantee for reliable 1553 B communication;design the way of receiving the total by combining command word stack and interrupt.Line message guarantees that the software does not lose messages.Closed-loop control strategy is designed according to the digital simulation results,and the control parameters are adjusted according to the actual debugging results to ensure the accuracy and stability margin of each closed-loop control.In order to verify the correctness of the software implementation,test cases are designed,and the software is verified on the target machine to ensure that the software implementation meets the functional and performance requirements of the servo system.The closed-loop control function,CAN bus program online download function,CAN bus parameter binding function,reliability and so on are mainly verified.The test results verify that the software is correct and can meet the requirements of the system. |
