Research on control strategy of high-performance CNC system based on open structure

Research on the control strategy of high-performance CNC system based on open structure Wang Junping, Fan Wen, Wang An, Jing Zhongliang 3 710072, 1 Xi’an: T: College, Xi’an 710032, Hai Jiaotong University, Shanghai backbone open architecture, will “I. Parts and CNC System warts as a unified whole consider how to improve the degree of detail. Cha arr7 open structure high-performance CNC system control strategy: open architecture, high-performance control f CNC system 1 control strategy in the classification number, TP273 text , A for S and U Ping (19H -), male (Han S>.KH Heyang County. Xizhi Gongzhengsheng from the previous digital machine tool and its numerical control system are moving towards speed. Huafalian. The main challenge of surface piles is to monitor the speed of processing and design the valve service controller. However, a new type of transmitter, advanced servo control algorithm a process control strategy si And the application division is under the control of the traditional failure control system architecture, so many scholars are committed to creating a new architecture, that is, the open architecture. This article is based on the open architecture. The workpiece and the CNC system are considered as a unity. The machining accuracy is improved by the open structure of the high-performance numerical control system calibration strategy i open a type control system architecture brief description of the CNC system is a special juice computer system, it is used for industrial field control, and There are many differences from general-purpose computers. For a long time, the development of the digital s system has become a system of its own. The establishment of its own software structure, the implementation of technical secrecy and technical sealing makes it difficult for machine tool manufacturers and end users to carry out secondary development and manufacture of machine tools. And the ability of the numerical control system, when the teaching and control machine tool enters the distributed control and flexible column manufacturing system environment, and even requires communication with the common network information system such as CAD/CAPP/CAM, some cnc installations that target stand-alone positions Too much is not enough, the new ring filling requirements. “”The device further transforms the open CNC system.

The open architecture adopts a hierarchical structure of blocks and connects to a unified application program through various forms, which is portable.

The characteristics of scalability, interoperability and scalability, that is, the internal openness of the system composition and the openness between the components of the system, and the system is based on the open structure. The control strategy of the performance numerical control system is composed of three parts: servo controller, multi-transmitting device detection and integration, and digital value processor. As shown in Kl 1, the processing system of Chen generation is supported by the servo system. . The parts of the servo system can play a crucial role in the degree of the workpiece, most of the industrial centers are equipped with a servo system. These servo M systems all use the traditional home counter library controllers with increasing accuracy requirements. Standard speed is no longer possible by relying on anti-friction control alone. This high-performance robust motion control is extremely important, and its purpose is to achieve a nominal health error close to the fi resolution string. To realize the full choice of EU, like a work boat, there are still many battles. The main point of ft is to design the A-speed high-speed servo controller in the presence of dynamic resistance and nonlinear discrimination uncertainty. When a servo controller with limited bandwidth is used, the Europium-linked delay becomes the main cause of position error. The reason is that it will affect the geometry of the workpiece slightly. The flSF system should have the cesium fixed rod and performance stinging. When the parameters of the dynamic system change, the performance is extremely playful. When designing high-performance rod motion controllers, these H kneadings should be based on the zinc composite feed friction compensation proposed by Lm and Totnimfca when designing high-performance rod motion controllers. The overall control structure of the disturbance detector, the position control potentiometer and the distilling device is an integrated control structure. Uncertainty makes the system more robust to the collation uncertainty. The feedforward ffi controller can adopt S-optimized measurement control. Zero phase error tracking control W. Repeated control ramping words to lift away the precision, position feedback control PID control is usually used. For nonlinear friction compensation, commonly used methods are: online compensation based on exponential nonlinear functions, inverted controller compensation based on neural network, robust repetitive control and variable structure control. But When the system parameters change greatly or the motion trajectory has discontinuous acceleration, DOB is not very appropriate. Yao and Tamizuka proposed a new motion control method, namely adaptive robust control, a performance servo based on adaptive robust control The system has good tracking performance.

Multi-sensor detection and information fusion In the processing of singular performance, the commonly used methods for improving the processing accuracy of the sculpture include error avoidance technology based on the accuracy of the machine tool and error compensation technology based on eliminating the error itself. The ultimate goal of these two methods is to reduce the machining error of the parts. This article considers how to improve the machining accuracy of the workpiece and the numerical control system as a unified whole, and connects the workpiece and the numerical control system through multi-sensor detection. Compared with a single sensor system, a multi-sensor information fusion system has the advantages of large amount of information, good fault tolerance, and ability to obtain characteristic information that cannot be obtained by a single sensor. The machining process is an extremely complex and changeable process, and changes in position, speed, temperature, and cutting force affect each other. Only by strengthening the collection and identification of these information, and obtaining reliable data can correct control be carried out. The corresponding signals are measured by a variety of sensors, and then the processing state information is sensed by multi-sensor information fusion technology, so as to provide the controller with true and reliable comprehensive information and improve the control accuracy.

With the increasing requirements for system information processing speed and real-time performance, with the development of large-scale integrated circuits, various chips dedicated to real-time digital signal processing have appeared. Compared with general-purpose microprocessors, their main There are two characteristics: DSP chips mostly use the Harvard structure, that is, the storage space of program instructions and data is separated, and each has its own address and data bus, which allows processing instructions and data at the same time, which greatly improves the processing efficiency; When a microprocessor executes an instruction, it takes several instruction cycles to complete, while the DSP chip adopts pipeline technology. Although the execution time of each instruction is still several instruction cycles, due to the pipeline operation of the instructions, it can be seen that each The final execution time of each instruction is completed in a single instruction cycle.

In the numerical control system, the digital signal processor completes the functions of data acquisition, trajectory generation, control strategy selection, and real-time control.

3 Conclusion This paper starts from the requirements of precision machining, uses multi-sensor information fusion technology to integrate the workpiece and the CNC system as a whole to consider how to improve the precision of the machining, and proposes a control strategy of the CNC system based on the open structure of the performance of the CNC system. This strategy is also valuable for the control of other sports bodies.

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