Design Of Real-Time Conctrol System For J1128H Die Casting Machine

The technical level and production capacity of die casting industry are important indicators about a country's industrial development level.However, there is still a certain gap on automation and control performance between domestic die-casting machine and advanced machine in the world.Therefore, it is imperative to develop roboticized and high-performance die casting machine based on the core of real-time control technology. A real time control system for J1128H-type die casting machine is designed in this paper.The main contents are as follows:In order to satisfy the requirement of real-time response performance, a distributed control system architecture is proposed, which is composed of management unit, control unit and execution unit.Different network bus technologies are adopted among these units. Specifically, the management unit communicates with the control unit through Ethernet.The control unit communicates with the execution unit through the CAN bus with the CANopen high-level protocol.And CAN bus is also adopted in the communication of all the execution subunits.The execution units, including data acquisition module, electro-hydraulic valve control module and switching value module, are designed based on Freescale MCU MC9S08DZ128 in which MSCAN is integrated. According to the principle of foreground and background programming in the software design of execution units, all CANopen slave stations are designed and both the information acquisition function and the corresponding control function are realized.All of the control functions in the control unit are realized based on the hardware platform of PC/104 bus industrial computer and the software platform of Linux/Xenomai dual-kernel real-time operating system. Multithread programming technology is adopted to schedule dual-kernel real-time system resources effectively. Besides, fuzzy adaptive PID control algorithm is used in the injection control system of die casting machine, which is nonlinear and large-time delay.AMESim and Simulink software are used to build the model of J1128H injection speed control system in which model of fuzzy adaptive PID control algorithm is embedded.The union simulation result indicates that fuzzy adaptive PID control has a good advantage on response speed, track performance and steady-state error in die casting machine injection control.Finnaly, modular test and comprehensive test are carried out to confirm the function of this control system.Test results show that both the function of all modules and the communication of Ethernet modules and CANopen stations are correct.