Real-Time Optimization And Software Development Based On Embedded Linux Wire Cutting Cnc System

EDM wire cutting is widely used in precision mold manufacturing,automotive,medical and other products processing because of its non-cutting force,not limited to the hardness and rigidity of the material.The development of domestic wire cutting CNC is still stuck in the form of PC + control card,which can no longer meet the requirements of modern CNC systems.Embedded technology has the advantages of customizable functions,low cost,and small size.Combining embedded technology with traditional CNC technology is of great significance for the upgrade of wire cutting CNC systems.Linux system has become a popular choice in the embedded field due to its open source code,tailorable kernel and stable performance.Therefore,under the general environment of China's transition to a manufacturing power,combining the advantages of embedded technology and Linux system,it is of great practical significance to develop a CNC system that meets the hard real-time requirements of CNC wire cutting.This paper mainly aims at optimizing the real-time performance of Linux system and trying to develop wire cutting CNC software on an embedded platform.To this end,this article mainly did the following research:1.Research on real-time performance of wire cutting and Linux system.This paper analyzes and studies the running status of real-time tasks in the process of WEDM,and the unpredictability of its scheduling delay in the general system,and finally puts forward the real-time requirements of WEDM CNC machining.Explain the real-time defects and optimization schemes of the Linux system,analyze the key technologies and deficiencies of real-time patch implementation,and use real-time patches to partially reform the real-time nature of the Linux system.2.Propose a new scheduling strategy.The Linux kernel process scheduling architecture,scheduler implementation principle and two mature hard real-time scheduling algorithms are compared and analyzed.The EDF algorithm will produce a chain reaction under CPU overload and cause all real-time tasks to be unsatisfied.Because the EDF algorithm will produce a chain reaction under CPU overload and cause all real-time tasks to be unsatisfied,a SPD algorithm that combines the priority of Linux real-time tasks with its absolute deadline to jointly determine the importance of real-time tasks.3.Implement and test new scheduling strategies.By implementing the SPD scheduling class,the new algorithm is added to the Linux kernel,and the real-time performance test is performed on the improved system.It is verified that the Linux kernel with the newscheduling algorithm added can meet the real-time requirements of the CNC system under light load and overload.4.Build software development environment and operating environment.By configuring TFTP and NFS services,the improved Linux kernel,u-boot,the root file system produced,and Qt / E are transplanted into the development board to complete the environment.5.Development of CNC software for EDM.Designed and implemented the main functional interface of the software,completed the important modules of the software,including file reading,code interpreter,interpolator,etc.,and transplanted into the target development board and tested it on the machine.