CN114594731A - CNC control method and system based on bus control - Google Patents

Abstract

The invention relates to the technical field of intelligent numerical control, in particular to a CNC control method and a system based on bus control; the invention adopts an open numerical control system mode and a high-integration embedding mode, thereby having high integration level and a simple and concise operation interface which is easy for personnel with numerous control technologies to operate; and data transmission is carried out based on a high-speed reliable bus, the anti-interference capability is stronger, the system is safer and more reliable, the customizability and expandability of the numerical control system are improved, the hardware structure that the traditional PLC and the controller are mutually independent is gradually replaced, the cost of the control system is greatly saved on the premise of stability and reliability, the system has a fully-modular software system structure and a real-time configuration system, and can be compatible with various software and hardware platforms, so that the software structure of the special numerical control system is broken through, and the system is not dependent on the condition of a hardware PLC controller.

Description

CNC control method and system based on bus control

Technical Field

The invention relates to the technical field of intelligent numerical control, in particular to a CNC control method and a system based on bus control.

Background

Industrial software is a product of fusion of industrial technology and information technology, so that the development of industrial software is difficult and expensive, and a mode of customizing products or developing dedicated application software is not an optimal choice.

Numerical control is short for digital control, and the numerical control technology is a method for controlling mechanical motion and a machining process by utilizing digital information. The numerical control module (NC) is an important subunit of an industrial software platform and is essential to the development of a CNC control system. According to the prediction report of the development prospect of the Chinese numerical control machine tool industry, at present, in the aspect of high-end numerical control machine tools, domestic products only account for 2 percent, while in popular numerical control machine tools, although the domestic production rate reaches about 70 percent, about 80 percent of domestic numerical control machine tools use foreign numerical control systems; the domestic numerical control system has obvious gaps in the aspects of high speed, high precision, five-axis machining, intellectualization and the like.

At present, a CNC control system mainly depends on a foreign numerical control system, world famous numerical control system manufacturers such as Japan, Semen of Germany, Heidenhain of Germany, Mitsubishi of Japan and the like occupy the numerical control system products with huge specific gravity, the domestic numerical control machine tool excessively depends on the foreign numerical control system, and the high-precision multi-axis numerical control system is also technically closed to China.

Most systems (represented by FUNAC, SIEMENS and the like) used in the current production adopt a special closed system structure, namely, hardware modules and software structures forming the system are designed by numerical control system manufacturers, are special and incompatible with each other, the interaction modes and communication mechanisms of the modules of the system are also different from each other, and although the numerical control system with the special closed structure has the advantages of simple structure, mature technology, large product batch and low production cost, the inherent defects of the system are more and more exposed as the market competition is intensified along with the progress of the technology, the interconnection capacity among the systems is poorer, the protocols are not matched, and the use and maintenance cost is increased; the system is limited in aspects such as secondary development, expansion of special technologies of users and integration of process experience in the system due to the sealing property of the system, formation of product characteristics of the system and the like; the special hard and software structure limits the continuous development of the system, so that the development investment of the system is large, the period is long, the risk is high, the updating is slow, and the technical progress of numerical control products is not facilitated.

Disclosure of Invention

The invention mainly solves the technical problem of providing a CNC control method based on bus control, which adopts an open numerical control system mode and a high-integration embedding mode, so that a simple and concise operation interface with high integration level is easy for personnel with numerous control technologies to operate; data transmission is carried out based on a high-speed reliable bus, the anti-interference capability is stronger, the system is safer and more reliable, and the customizability and expandability of the numerical control system are improved; a CNC control system based on bus control is also provided.

In order to solve the technical problems, the invention adopts a technical scheme that: the CNC control method based on bus control is provided, and comprises the following steps:

s1, embedding the integrated CNC controller into a control system of the numerical control machine tool, wherein the CNC controller is connected with a control panel of the machine tool through a control bus;

step S2, connecting the upper computer and the CNC controller through a control bus and performing data interaction;

s3, the development design module transmits the edited control program and library file to the CNC controller, and transmits the control program in the CNC controller to the numerical control execution platform through a signal command by operating the upper computer;

and step S4, setting parameters by operating the machine tool control panel, and controlling the numerical control execution platform to work according to the signal command of the control program in the CNC controller.

As an improvement of the present invention, in step S3, the data storage module may store the control program of the development design module and the setting parameters of the control system of the numerical control machine tool.

As a further improvement of the present invention, in step S3, the data acquisition module may call the data stored in the data storage module.

As a further improvement of the present invention, in step S3, the data acquisition module transmits the called data to the CNC controller.

As a further improvement of the present invention, the development design module may modify data stored in the data storage module.

As a further improvement of the invention, the data storage module stores data in the form of a database.

As a further improvement of the invention, the upper computer, the development and design module, the data storage module and the data acquisition module are all integrated on the CNC controller.

A CNC control system based on bus control, comprising:

the CNC controller is used for being connected with a machine tool control panel;

the upper computer is used for being connected with the CNC controller through a control bus and carrying out data interaction;

and the development design module is used for transmitting the edited control program and the library file to the CNC controller.

As an improvement of the present invention, the present invention further comprises:

and the data storage module is used for storing the control program of the development and design module and the setting parameters of the control system of the numerical control machine.

As a further improvement of the invention, the method also comprises the following steps:

and the data acquisition module is used for calling the data stored in the data storage module.

The invention has the beneficial effects that: compared with the prior art, the invention adopts an open numerical control system mode and a high-integration embedding mode, thereby having high integration level and a concise and concise operation interface which is easy for personnel with numerous control technologies to operate; and data transmission is carried out based on a high-speed reliable bus, the anti-interference capability is stronger, the system is safer and more reliable, the customizability and expandability of the numerical control system are improved, the hardware structure that the traditional PLC and the controller are mutually independent is gradually replaced, the cost of the control system is greatly saved on the premise of stability and reliability, the system has a fully-modular software system structure and a real-time configuration system, and can be compatible with various software and hardware platforms, so that the software structure of the special numerical control system is broken through, and the system is not dependent on the condition of a hardware PLC controller.

Drawings

FIG. 1 is a block diagram of the steps of a CNC control method based on bus control of the present invention;

FIG. 2 is a block diagram of a CNC control system based on bus control of the present invention;

FIG. 3 is an interaction diagram of a CNC controller with a host computer, design development module, according to an embodiment of the present invention;

FIG. 4 is a functional schematic of the operation of one embodiment of the present invention;

fig. 5 is a flow chart illustrating the preparation of a T-command cutterhead supporting a T-function according to an embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

Referring to fig. 1 to 5, a CNC control method based on bus control of the present invention includes the following steps:

s1, embedding the integrated CNC controller into a control system of the numerical control machine tool, wherein the CNC controller is connected with a control panel of the machine tool through a control bus;

step S2, connecting the upper computer and the CNC controller through a control bus and performing data interaction;

s3, the development design module transmits the edited control program and library file to the CNC controller, and transmits the control program in the CNC controller to the numerical control execution platform through a signal command by operating the upper computer;

and step S4, setting parameters by operating the control panel of the machine tool, and controlling the numerical control execution platform to work according to the signal command of the control program in the CNC controller.

In the invention, an open numerical control system mode is adopted, and a high-integration embedding mode is adopted, so that the high-integration-level, simple and concise operation interface is easy for a person with numerous control technologies to operate; and data transmission is carried out based on a high-speed reliable bus, the anti-interference capability is stronger, the system is safer and more reliable, the customizability and expandability of the numerical control system are improved, the hardware structure that the traditional PLC and the controller are mutually independent is gradually replaced, the cost of the control system is greatly saved on the premise of stability and reliability, and the system has a full-modular software system structure and a real-time configuration system and can be compatible with various software and hardware platforms.

At present, most numerical control systems in the market adopt a special closed system structure, depend on hardware modules of various manufacturers in large quantity, have strong specificity and are incompatible with each other, cause the dependence of users in the middle of a numerical control system integrator system on system suppliers, are difficult to integrate own special techniques and process experiences into a control system and form own product characteristics, are not beneficial to improving the competitiveness of host products, and the special hardware and software structures limit the continuous development of the system, so that the development investment of the system is huge, the development cycle time is long, the risk is overhigh, the updating and updating speed is slow, and the product application of the numerical control technology is not beneficial.

The invention breaks through the software structure of a special NC control system, does not depend on a hardware PLC controller, has a full-modular software system structure and a real-time configuration system, and can be compatible with various software and hardware platforms.

In the present invention, in step S3, the data storage module may store the control program of the development design module and the setting parameters of the control system of the numerical control machine tool; further, the data storage module stores data in the form of a database.

In the invention, the data acquisition module can call the data stored in the data storage module, and the data acquisition module transmits the called data to the CNC controller; meanwhile, the development and design module can modify the data stored in the data storage module.

In the invention, the upper computer, the development and design module, the data storage module and the data acquisition module are all integrated on the CNC controller, thereby achieving high integration.

As shown in fig. 3 to 5, the present invention provides an embodiment, which provides a standard IDE development environment based on a CoDeSys kernel framework structure, supports a standard communication protocol, supports multiple high-level programming languages, has an attractive and compact HMI interaction interface, and uses a set of hardware platform to perform data interaction with NC, PLC, and MCP through an internal protocol mechanism, thereby implementing rich NC functions such as CNC axis motion control, magnification selection, single step execution, alarm log, tool measurement, coordinate system measurement, and the like.

The embodiment improves the customizability and expandability of the numerical control system, gradually replaces the traditional hardware structure that the PLC and the controller are mutually independent, and greatly saves the cost of the control system on the premise of stability and reliability.

As shown in fig. 2, the present invention provides a CNC control system based on bus control, which includes:

the CNC controller is used for being connected with a machine tool control panel;

the upper computer is used for being connected with the CNC controller through a control bus and carrying out data interaction:

the development design module is used for transmitting the edited control program and the library file to the CNC controller;

the data storage module is used for storing the control program of the development and design module and the setting parameters of the control system of the numerical control machine;

and the data acquisition module is used for calling the data stored in the data storage module.

The invention can be based on various bus forms, wherein an EtherCAT bus is taken as an example, and the EtherCAT achieves a new height on the network performance; the refresh period of 1000 distributed I/O data is only 30 mus, which includes terminal cycle time, up to 1486 bytes of process data can be exchanged through one Ethernet frame, which is almost equivalent to 12000 digital I/O, and the transmission of the data amount only uses 300 mus, and through the super-high speed control loop formed by the bus, great support can be provided for real-time data update of the numerical control system, and the control frequency can reach higher.

Specifically, in the embodiment, the development design module can be divided into IDE development environment program development (PLC, NC) and RTE component development based on the CoDeSys, the IDE and the controller are converted into binary codes through the CoDeSys and are issued to the CNC controller, the upper computer realizes a GUI interface interaction function, the GUI adopts a QT application development framework and is responsible for data interaction between an operator and the CNC controller through the interface, the upper computer and the CNC control system interact in a memory sharing manner, functions of configuration information, machine tool control, parameter setting and the like are issued to the CNC controller, and data of some important data in the control system, which need to be stored in a power failure mode, are stored and accessed through an SQLite open source database.

The CNC controller realizes the control and driving functions of machine tool equipment, needs to communicate with external machine tool equipment, external IO modules and the like, CoDeSys almost integrates all general industrial control buses such as EtherCAT and the like, meets different bus requirements in actual work, realizes bus control of a driving system, peripheral equipment and the like, HMI (human machine interface) in an upper computer provides a friendly editing interface and various programming environments, and is convenient for an operator to edit G codes and monitor data information in real time and the like on the interface, the HMI is a graphical display interface of the upper computer, the HMI and the CNC controller share one set of control hardware, the HMI program development adopts a QT application program development framework, is responsible for data interaction between the operator and the CNC controller through the interface, the HMI and the CNC controller adopt defined internal protocols for interaction, realize the issuing of some configuration information, machine tool control, parameter setting and other functions to the CNC controller, and receive current state information returned by the CNC controller and shaft information, and the control, Coordinate system, tool related information, etc.; and displaying state information such as the execution of the G code to the row, shaft position values, equiaxial motion data of the rotating directions of all shafts, commands such as NC program operation and stop, bus states and periods, alarm states and the like.

The CNC controller adopts a LINUX Ubuntu-based real-time operating system, hardware adopts an embedded controller, a development layer adopts a CoDesys development and compilation environment, a controller kernel adopts a real-time kernel system, an NC kernel is developed on the basis of a CoDesys software translation (CNC) module, and IEC codes are compiled into machine codes and downloaded to the runtime. As shown in fig. 4, executing a CNC control process mainly implements processing of a G code file issued by an HMI through an NC kernel, interpolating the G code file into an interpolation point of robot motion through a CoDeSys CNC interpolator, and issuing the G code file to a numerical control hardware platform through a main stream bus supported by the CoDeSys itself, implementing machine tool processing, implementing an interactive process with the HMI, implementing real-time display of a motion state and a position by building a component requiring implementation of a function module in a runtime kernel, and packaging the building of each component into an independent library function.

In this embodiment, the numerical control execution platform is configured to receive bus data issued by the CNC controller and implement the motion path motion planned by the G code, and different numerical control execution mechanisms need to perform configuration of related configuration files according to a given model, or may establish a corresponding model through forward and inverse kinematics, which may support secondary development of customers.

In this embodiment, the machine control panel MCP, via which actions can be released to the machine, for example: running a shaft or beginning to process a workpiece, etc.; the selectable MCP panel of CNC controller is full keyboard type, and is mutual through standard bus, and MCP panel function can be divided into PLC function button and NC function button, and PLC and NC function all carry out the function block development through the IDE development environment that CoDesys provided, realizes the control panel operation.

The CoDesys IDE in the development and design module is used for compiling CNC, PLC control function processes and related library files and sending programs and libraries to the CNC controller for execution, and the CoDesys IDE has functions of an editor, a configurator, a compiler, a debugger and the like, can realize G code compiling, PLC program compiling and NC program pre-reading module realizing NC file calling and G code processing, and the IDE supports six programming languages of IEC 61131-3 international standard and DIN66025 programming language (G code).

As shown in fig. 5, in order to implement a numerical control machining task, machine tool equipment, a tool magazine and system parameters need to be set, corresponding data interaction such as a tool table, alarm information and the like is performed with a CNC controller through an HMI, and a mode needs to be provided to complete data storage, data calling, system parameter power-down maintenance, alarm data, tool magazine state storage and the like; the data storage module adopts a database form to store related data, the occupied resource is very low, only hundreds of K of memories are enough in the embedded device, in the system, a complete database is stored in a single disk file, related data in the NC control collected by the data collection module is stored in a data table, and system parameters, CNC related data such as a tool table and other information are also stored in the database; the development design module can realize the functions of adding, deleting, modifying and searching a database, realize the data storage and calling of the CNC control system, and define related variables as global types for the calling of an NC program and a PLC program.

Because available G codes provided by CoDesys are limited, and the currently supported M function needs to be developed by self, T, D and other related functions are different from CNC systems of mainstream manufacturers, the T function is not supported, and the D function only can correspond to the radius value of a cutter and the like; in order to realize the functions of corresponding G codes, M functions, T functions and the like, a subprogram calling function provided by CoDesys IDE is needed; tasks that are frequently repeatedly performed (e.g. cavity milling, hole drilling and tool changing) can be exchanged for and called from the G-code subprogram, during which the parameters can be passed to the subprogram; to this end, the data types BOOL, LREAL and STRING are allowed, each sub-program being stored in a separate file that is saved in one or more subdirectories on the controller, which must have a file extension. Subroutine name "Drill" - > file name Drill.

The CNC control system can be expanded to a multi-channel system, can integrate a digital twin function, can provide a three-dimensional simulation platform for a user, provides a visual test environment for a generated G code program, has the functions of virtual debugging, offline programming and the like, and increases an intelligent control concept on the basis of the traditional numerical control system; the numerical control processing data of the system can be uploaded to an MES system through an industrial bus to carry out unified management on the product materials and the processing data, and a good foundation and a good technical prospect are laid for realizing industrial 4.0.

The invention is used as a product of the domestic numerical control system technology, is mainly used for specific numerical control processing equipment, realizes a domestic numerical control high-speed, high-precision and intelligent numerical control system, can be suitable for a common numerical control system and a special numerical control system, has a modular structural design, and fully exerts and embodies expandability and transportability among modules.

The invention also obtains corresponding improved functions in the design development of the process and machine tool model and the cutter compensation, can realize the switching of the machine tool and the corresponding tool and workpiece measurement functions by adding the subprogram function, provides a high-speed, high-precision and intelligent numerical control system platform for customers, integrates industrial software system data interaction interfaces such as MES and the like, can realize the industrial 4.0 customized development and provides a better numerical control solution for small-batch customers; the mode can rapidly absorb the latest achievement of the computer technology, has good flexibility and expandability, can conveniently adopt a new control method, and is easy to realize the updating and upgrading of physical equipment and an operating system; due to the moir effect of the advances in processor technology, motion controller components that appear in hardware can be implemented entirely in software within a predictable time. With the continuous progress of the processor performance and the operating system technology, the "hardware function software" will not cause any system performance loss, and the flexibility of software implementation and the independence of the hardware platform will be beneficial to the deeper openness of the system implementation and the rapid increase of the system performance, which is the basic idea of "software numerical control" and is the implementation basis of the complete openness of the numerical control system.

Various functions of the numerical control system, such as compiling, explaining, interpolating, PLC functions, process aspects and the like, are realized by software modules. The invention can realize the opening of the system architecture through proper organization, division, specification definition and development of software by means of the prior operating system platform and under the support of application software CoDesys. The hardware cost under the control mode can be reduced to the minimum, and compared with the traditional numerical control system on the market at present, the system has the advantages of better integration level and better platform openness, and the development period of the specific numerical control system which is easy to carry out secondary development on users can be greatly shortened. In the aspect of numerical control function, the invention integrates the digital twin function, can effectively improve the efficiency and visual feeling of programmers, is easier to use and has richer functional interfaces. And the system does not depend on hardware, breaks the blockade and monopoly value of the traditional foreign numerical control system to the domestic market, and lays a good foundation for the development of the domestic numerical control technology.

The invention has the following beneficial effects:

1. the brand new CNC control system is developed, an open and modularized design structure is adopted, secondary development is carried out on the basis of CoDesys IDE, a reliable and efficient bus control mode is achieved, an execution mechanism model capable of being developed secondarily is enriched, monopoly of an international numerical control system is eliminated, the architecture of a multi-axis numerical control system can be supported, and a developable system platform is provided for traditional and special numerical control machining.

2. The method has the advantages that the high integration level of hardware is realized, the NC function, the PLC control function and the HMI are integrated in one embedded controller, the method is in clear contrast with the realization of multiple controllers such as the PLC, the controller and the HMI of the traditional numerical control system, the compatibility is optimized, and the hardware cost is greatly reduced.

3. The method has the advantages that a digital twin function module and an open industrial bus are built, processing data can be collected and perfectly linked with an MES system in a digital factory, customization and development of the system are supported, the universality of a development environment is stronger, and various operating systems (windows \ Linux \ VxWorks and the like or no operating system) can be supported.

4. The method has rich debugging and simulation environments, can realize the loop simulation function of the numerical control system, can simulate real testing and debugging conditions, including sequence and motion control, and enables a user to perform more intuitive simulation teaching operation on a program.

The above description is only an embodiment of the present invention, and not intended to limit the scope of the present invention, and all modifications of equivalent structures and equivalent processes performed by the present specification and drawings, or directly or indirectly applied to other related technical fields, are included in the scope of the present invention.

Claims (10)

1. A CNC control method based on bus control is characterized by comprising the following steps:

s1, embedding the integrated CNC controller into a control system of the numerical control machine tool, wherein the CNC controller is connected with a control panel of the machine tool through a control bus;

step S2, connecting the upper computer and the CNC controller through a control bus and carrying out data interaction;

s3, the development design module transmits the edited control program and library file to the CNC controller, and transmits the control program in the CNC controller to the numerical control execution platform through a signal command by operating the upper computer;

and step S4, setting parameters by operating the machine tool control panel, and controlling the numerical control execution platform to work according to the signal command of the control program in the CNC controller.

2. The method of claim 1, wherein the data storage module stores the control program of the development design module and the setting parameters of the control system of the CNC machine in step S3.

3. The CNC control method based on bus control as claimed in claim 2, wherein in step S3, the data acquisition module can call the data stored in the data storage module.

4. The CNC control method based on bus control of claim 3, wherein in step S3, the data acquisition module transmits the called data to the CNC controller.

5. The method of claim 4, wherein the development design module modifies data stored in the data storage module.

6. The CNC control method based on bus control as claimed in claim 2, wherein the data storage module stores data in the form of database.

7. The CNC control method based on bus control of claim 5, wherein the host computer, the development and design module, the data storage module and the data acquisition module are all integrated on a CNC controller.

8. A CNC control system based on bus control, characterized by comprising:

the CNC controller is used for being connected with a machine tool control panel;

the upper computer is used for being connected with the CNC controller through a control bus and carrying out data interaction;

and the development design module is used for transmitting the edited control program and the library file to the CNC controller.

9. The CNC control system based on bus control of claim 8, further comprising:

and the data storage module is used for storing the control program of the development and design module and the setting parameters of the control system of the numerical control machine.

10. The CNC control system based on bus control of claim 9, further comprising:

and the data acquisition module is used for calling the data stored in the data storage module.

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