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

Research on control strategy of high performance CNC system based on open architecture Wang Junping, Fan Wen, Wang An, Jing Zhongliang 3 710072, 1 Xi'an: T: college, Xi'an 710032, Shanghai backbone open architecture of Haijiao Tong University, Take "I. parts and CNC system" as a unified whole and consider how to improve the s degree of fine work. Cha arr7 high-performance CNC system control strategy of open structure a: open architecture, high-performance control f CNC system 1, clear classification number in control strategy, tp273 document, a as s medium u level (19h ―), male (Han s >. KH, from Heyang County. He was born in the West. He was born in the West. The machine tool and its numerical control system are moving towards speed. A slightly more intelligent, intelligent and integrated development. The main challenge of the face pile is to realize the monitoring of the speed machining process and design the supporting valve service controller. However, the development Si and application of the new transmitter, advanced servo control algorithm and process control strategy have been influenced by the traditional control system system Therefore, many scholars are committed to establishing a new architecture, that is, open architecture. This paper focuses on open architecture. Taking the workpiece and numerical control system as a whole, considering how to improve the machining accuracy, and putting forward the calibration strategy of the off-performance numerical control system in the open structure. I. brief introduction of the architecture of the open A-type control system. The numerical control system is a special juice computer system, which is used for industrial field control, but it is different from the general computer. For a long time, the number s system has developed into its own system. Establish their own soft stem structure, implement technical confidentiality and technical sealing, so that it is difficult for machine tool manufacturers and end users to carry out secondary development, and develop the ability of machine tool and NC system. When the teaching and control machine tool enters the distributed control and flexible column manufacturing system environment, and even requires communication with common network systems such as CAD / CAPP / CAM, Some CNC equipment aimed at stand-alone jobs is not enough, and the new environmental filling requirements. "The device is further transformed into an open CNC system.

The open architecture Yi Trent adopts a block hierarchical junction HN and provides a unified application connection P through various forms, which is portable.

Scalability, interoperability and scalability, that is, the internal openness of the system composition and the openness between the components of the system. 2. According to the system policy, the basket performance CNC system control strategy based on the open structure is composed of three parts: servo controller, multi FFI detector and information combination, and digital value processor, as shown in KL 1, Chendai processing system is supported by tantalum system. Before the components of the servo system can play a crucial m role in the accuracy of the workpiece, most industrial centers are equipped with servo systems. These servo m systems use traditional home 0 anti library controllers, which are more and more popular with the requirements of fidelity. The control of classical speed such as work order is no longer available - s this high-performance robust motion control is very important. Its purpose is to realize that the nominal congruence error is close to fi resolution string. In order to realize the full choice of europium, such as engineering, there are still many peach wars. FT is the main reason, especially in the case of anti dynamic and nonlinear identification uncertainty m, the a-speed high degree servo controller is designed. When the limited bandwidth servo controller is used, the europium coupling delay becomes the main cause of position error, which will affect the geometric degree of the workpiece. The flsf system should have cesium fixing rod and performance sting rod. When the parameters of the dynamic system pit change, The performance is very good. These nets 1 will be more strict with the increase of feed speed during slamming. When designing high-performance rod motion controller, these h rubs should be based on the zinc feed friction compensation proposed by Colm and totnimfca. The overall control structure integrating the disturbance detector, the position anti library control charmer and the fractionator, that is, the high-performance buried system (DOB) based on the disturbance detector, Disturbance gauge The feedforward FFI controller can adopt s-optimal measurement control. Zero phase error tracking W. repetitive control skew to improve the range accuracy, and the position feedback control usually adopts PID control. For nonlinear friction force compensation, the commonly used methods are: online compensation method based on exponential nonlinear function, based on Neural network inverse controller compensation method, robust repetitive control and variable structure control. However, when the system parameters change greatly or there is discontinuous acceleration in the motion trajectory, DOB is not very appropriate. Yao and tamizuka proposed a new motion control method, namely adaptive robust control. The basket performance servo system based on adaptive robust control has good tracking performance.

Multi sensor detection and information fusion in basket performance processing, the common methods of basket processing accuracy include error avoidance technology based on the accuracy of basket machine tool and error compensation technology based on eliminating the error itself. The purpose of these two methods is to reduce the machining error of parts. This paper takes the workpiece and NC system as a unified whole, considers how to improve the basket machining accuracy, and connects the workpiece and NC system through Multi-sensor Detection. Compared with single sensor system, multi-sensor information fusion system has the advantages of large amount of information, good fault tolerance and obtaining characteristic information that can not be obtained by a single sensor. The machining process is an extremely complex and changeable process, and the changes of position, speed, temperature and cutting force affect each other. Only by strengthening the collection, identification and processing of these information and obtaining reliable data can it be controlled correctly. The corresponding signals are measured by a variety of sensors, and then the multi-sensor information fusion technology is used to sense the processing state information, so as to provide the controller with real and reliable comprehensive information and improve the control accuracy.

With the increasing demand for the speed and real-time of system information processing, and with the development of large-scale integrated circuits, there are various chips DSP dedicated to real-time digital signal processing Compared with general-purpose microprocessors, its main characteristics are two: most DSP chips adopt Harvard structure, that is, the storage space of program instructions and data is separated, and each has its own address and data bus, which makes the processing instructions and data can be carried out at the same time, which greatly improves the processing efficiency; When a general-purpose microprocessor executes an instruction, it needs several instruction cycles to complete it. The DSP chip adopts pipeline technology. Although the execution time of each instruction is still several instruction cycles, due to the flow of instructions, taken together, 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 starting from the requirements of basket precision machining, this paper takes the workpiece and NC system as a unified whole through multi-sensor information fusion technology, considers how to improve basket machining precision, and puts forward the control strategy of basket Performance NC system based on open structure. This strategy is also valuable for the control of other moving bodies.

Huang Jinqing et al. Development of high performance CNC system based on open structure. Manufacturing technology and machine tools, 1998 (8): 1416, Chen Meihua et al. Development and application of intelligent modeling and prediction technology of machining error. Journal of Yunnan University of technology, 1998, 14 (3): 69 Liao Degang. Research and development status of open CNC system.

Post time: Jan-16-2022