A machining center FANUC coordinate system protection method

Abstract

The application discloses a machining center FANUC coordinate system protection method, comprising the following steps: step S1: dividing the coordinate system parameters according to the importance degree to divide the protection level, switching the parameter write protection control right to the PMC signal through the system parameter setting, and writing the permission judgment logic in the PMC ladder diagram; step S2: constructing the background parameter monitoring mechanism based on the macro program interruption function and the PMC window function, periodically reading the current value of each level parameter and comparing with the reference value; step S3: triggering the differential early warning and processing mechanism according to the safety level of the modified parameter, and automatically executing the parameter backup after the authorized modification confirmation; step S4: establishing the log buffer area in the PMC, and real-time recording the coordinate system related operation behavior and storing in the non-volatile area. The application can cover more than 90% of the FANUC system machining center on the market, and can be used for self-owned factory equipment batch upgrading, and can also carry out technical service, technical consultation and technology transfer.

Description

Technical Field

[0001] This invention relates to the field of CNC machining technology, and in particular to a method for protecting the FANUC coordinate system of a machining center. Background Technology

[0002] FANUC CNC systems are currently the most widely used machining center control systems in the global machining industry. In CNC machining, the accuracy of coordinate system parameters directly determines the machining precision and safety of parts. The workpiece coordinate system (G54~G59) stores the offset between the workpiece zero point and the machine tool reference point. Tool length compensation parameters (shape compensation and wear compensation) determine the actual cutting position of the tool, and machine tool origin setting parameters (such as the APZ position in parameter 1815) are directly related to the absolute position reference of the machine tool. If these core parameters are mistakenly modified, it can lead to parts being scrapped due to out-of-tolerance conditions, or even collisions between the tool and the workpiece or worktable, causing permanent damage to core components such as the spindle and guideways.

[0003] Currently, the industry's protection against misoperation of FANUC coordinate system parameters mainly suffers from the following technical deficiencies: (1) Protection measures rely on external hardware, resulting in high modification costs and long deployment cycles. In existing technologies, some solutions use mechanical error-proofing devices, such as coordinate system calibration through mechanical components like calibration rods, adjustment brackets, bases, and fixing plates. This requires additional mechanical hardware devices, leading to high modification costs per unit and long installation and commissioning cycles, making it unsuitable for widespread adoption by small and medium-sized machining enterprises. Other solutions achieve protection through external control boxes, access locks, etc., which also require modification of the machine tool's electrical wiring, resulting in a significant workload for modifying existing equipment.

[0004] (2) Incomplete protection coverage and security vulnerabilities exist. The tool offset misoperation prevention function built into the FANUC system (set in the misoperation prevention interface of the SETTING screen) can limit the input range of tool offset (for example, setting the tool length wear range of T17~T20 to -1.0~0.8, and prompting an alarm when the input data exceeds the range), but this function only covers tool offset parameters and depends on the operator to set it manually. Most existing solutions only provide basic protection for the G54~G59 workpiece coordinate system, ignoring the protection of core reference parameters such as machine origin setting parameters (parameter 1815), machine coordinate system offset parameters (parameters 1240~1243), and reference point limit parameters (parameters 1320~1325). Once these parameters are mistakenly changed, they will also cause serious machining accidents.

[0005] (3) The access control mechanism is crude and cannot achieve precise hierarchical control. The key switch lock panel or PWE parameter write protection switch mode commonly used in the industry has too coarse control granularity. When PWE (parameter write enable, corresponding to parameter 8900#0) is set to 1, all parameters can be modified, and when it is set to 0, none can be modified, which cannot achieve fine hierarchical management. Key switches generally have problems such as key sharing, not removing the key after temporary authorization, and password leakage, which cannot fundamentally prevent unauthorized modification behavior. Although the parameter protection control can be switched to signal G46.0 (KEYP signal) through parameter 3299#0 (PKY bit) to achieve write protection control through PMC signal, the existing technology lacks a complete solution to systematically bind this underlying mechanism with user identity and operation permissions.

[0006] (4) Lack of a sound emergency recovery and traceability mechanism. Existing solutions generally only achieve basic access control and lack automatic parameter backup and one-click recovery functions. Once an accidental modification occurs, it is necessary to re-set the tool and find the origin, which can cause downtime of up to several hours, seriously affecting the production continuity of batch parts. At the same time, the lack of an immutable operation log recording function makes it impossible to trace the modification history of coordinate system parameters and the person responsible for the operation, which does not meet the traceability requirements of the ISO9001 quality management system in the machining industry. Summary of the Invention

[0007] To address the aforementioned technical problems, this invention provides a method for protecting the FANUC coordinate system of a machining center.

[0008] This invention is achieved using the following technical solution: a method for protecting the FANUC coordinate system of a machining center, comprising the following steps: Step S1: Divide the coordinate system parameters into protection levels according to their importance, switch the parameter write protection control to the PMC signal through system parameter settings, write the permission judgment logic in the PMC ladder diagram, map the three physical positions of the key switch to three user identity levels: operator, programmer and administrator, and combine password verification to dual control the write permissions of parameters at each level. Step S2: Based on the macro program interrupt function and PMC window function, a background parameter monitoring mechanism is constructed. The current value of each level parameter is periodically read and compared with the reference value. When unauthorized modification is detected, a three-level interception action is executed in sequence: locking the parameter writing channel, cutting off the feed axis enable, pausing the machining program and triggering an alarm. Step S3: Trigger a differentiated warning and processing mechanism based on the security level of the modified parameters, and automatically perform parameter backup after authorization modification confirmation, and write back the backup data in batches through the one-click recovery interface; Step S4: Establish a log buffer in PMC to record coordinate system-related operations in real time and store them in a non-volatile area. The recorded data must not be deleted or modified.

[0009] Furthermore, the protection level in step S1 specifically includes: Core-level parameters can only be unlocked and modified if both conditions are met simultaneously: the key switch is in the administrator-only position and the administrator password is entered. If no modification is performed within 10 minutes after unlocking, the privilege will be automatically revoked. Important parameters can only be unlocked and modified if both conditions are met: the key switch is in the authorized position and the corresponding user password is entered. After unlocking, the device will automatically lock if there is no operation for 15 minutes. Normal-level parameters are only temporarily accessible and are automatically cleared after program execution.

[0010] Furthermore, the macro program interrupt function in step S2 specifically configures a background resident interrupt macro program through system variables, and sets the interrupt scan period to 50~200ms. The core function of the interrupt macro program is to periodically read the current values ​​of core-level parameters and important-level parameters and compare them with the preset reference values ​​in the system ROM.

[0011] Furthermore, the PMC window function in step S2 includes: reading core-level parameters by reading parameter function code number, reading workpiece coordinate system variables by reading workpiece origin offset function code number, and reading tool compensation system variables by reading tool offset function code number.

[0012] Furthermore, the three-level interception action in step S2 specifically includes: Level 1: Disable parameter writing enable from the bottom layer via the G46.0 signal, and prevent access to the coordinate system modification screen by locking the SYSTEM function key; Level 2: By sending the G8.4=0 signal, the CNC is put into emergency stop state, and the feed enable signals of each servo axis are cut off; Level 3: Pause the execution of all current processing programs and display custom alarm information on the system screen via the Information Display Function (DISP) command.

[0013] Furthermore, the differentiated early warning and processing mechanism in step S3 specifically includes: For abnormal modifications to ordinary parameters, only a prompt message box will pop up on the system panel, without triggering a lockout or alarm; For any abnormal modification of critical parameters, the three-level interception mechanism in step S2 is immediately triggered. The system alarms and locks the feed axis. Only users with programmer or administrator privileges can unlock it after entering the correct password. For abnormal modifications to core parameters, the machine tool will be immediately locked and shut down, the spindle and all servo axes will be disabled, and the highest level alarm will be triggered. The machine can only be unlocked and restored after the highest administrator completes password verification and operation confirmation. Manual verification of the modified core parameters is also required.

[0014] Furthermore, the automatic backup process in step S3 specifically includes: The complete values ​​of all core-level parameters, important-level parameters, and ordinary-level parameters can be read sequentially using the function code numbers for reading parameters, reading workpiece origin offset, and reading tool offset in the PMC window. The read data is packaged in a structured format that includes a backup file header, core parameter blocks, important parameter blocks, and a backup file footer; The generated encrypted backup file is stored in the hidden partition of the system's built-in CF card or in the non-volatile storage area of ​​the system's FROM / SRAM; A circular storage strategy is used to automatically retain at least 20 recent historical backup versions.

[0015] Furthermore, the one-click recovery specifically refers to: entering the coordinate system one-click recovery interface through the custom soft key on the system panel. This interface displays all historical backup files in a list format, with each list item including the backup time, operator number, and backup trigger reason.

[0016] Furthermore, the operation behaviors include: parameter viewing operation, parameter modification operation, permission verification operation, backup operation, recovery operation, and alarm cancellation operation. Each operation type corresponds to a unique operation code. Log data is written to the system's non-volatile storage area through the PMC's MOVW word transfer instruction. This area is written-protected by the system hardware, and only the highest administrator can read the log content through a dedicated data viewing interface.

[0017] Furthermore, the log buffer supports log retrieval and filtering based on multiple dimensions such as time range, operator, and operation type, and supports exporting log reports.

[0018] The beneficial effects of this invention are as follows: This invention is entirely based on the native PMC programming, macro program interrupt, system variable read / write, and parameter configuration functions of the FANUC system. It requires no external hardware installation or modification of the machine tool's electrical wiring, and the configuration cycle for a single device does not exceed 2 hours. It is compatible with the entire FANUC 0i / 16i / 18i / 21i / 30i / 31i series systems, covering over 90% of FANUC system machining centers on the market. It can be used for batch upgrades of equipment in one's own factory, and can also be used to provide technical services, technical consultation, and technology transfer to external parties.

[0019] This invention covers all core positioning parameters, including machine tool origin parameters (parameter 1815), reference point offset parameters (parameters 1240-1243), soft limit parameters (parameters 1320-1325), workpiece coordinate system (G54-G59), and tool length and radius compensation parameters. Its protection scope far exceeds the single tool offset misoperation prevention function built into the FANUC system. The three-level protection system, through hierarchical access control and a three-level real-time interception mechanism, completely solves management loopholes such as key sharing and unauthorized operations, constructing a complete protection chain from three levels: parameter writing prohibition, axis motion interruption, and program execution suspension.

[0020] This invention does not alter the original basic operating procedures and habits of the machine tool. The protection function runs silently in the background, triggering interception and alarm only when an anomaly occurs. Frontline operators require no additional training; only simple permission configuration training is needed for administrators and programmers to use it normally, without requiring adjustments to the existing production process. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0022] Figure 1 This is a flowchart of the present invention. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0024] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0025] The following detailed description of some embodiments of the present invention is provided in conjunction with the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0026] See Figure 1A method for protecting the coordinate system of a FANUC machining center is disclosed. This method is entirely based on the native PMC (Programmable Machine Controller) programming function, macro program interrupt function, system variable read / write function, and system parameter configuration function of the FANUC system. No modifications to the mechanical structure or electrical wiring of the machining center are required. Specifically, the method includes the following steps: Step S1: Configure the hierarchy and permission mapping of core coordinate system parameters; Step S2: Real-time monitoring and write interception of full-cycle coordinate system parameters; Step S3: Abnormal state graded early warning and one-click recovery mechanism; Step S4: Full recording and traceability management of coordinate system operation behavior.

[0027] In this embodiment, step S1 specifically includes: First, all coordinate system parameters and system variables related to machining positioning accuracy in the FANUC CNC system are systematically classified according to their importance and safety level, forming three protection levels.

[0028] Core-level parameters (highest protection level) include: machine origin setting parameters (the 4th digit APC and the 5th digit APZ of parameter 1815), machine coordinate system offset parameters (parameter 1240 is the coordinate value of the first reference point in the machine coordinate system, and parameters 1241-1243 are the coordinate values ​​of the second, third, and fourth reference points, respectively), positive direction soft limit parameters (parameter 1320), and negative direction soft limit parameters (parameter 1321). These parameters directly determine the absolute position reference of the machine tool and the safe travel range of each axis. Incorrect modification may lead to the machine tool failing to return to zero normally, overtravel and loss of control of each axis, or mechanical collisions, with the most serious consequences. Therefore, core-level parameters are only accessible to the highest-level administrator. Unlocking and modification requires both the key switch being in the administrator-only position and a 6-digit administrator password being entered. If no modification is performed within 10 minutes of unlocking, the system will automatically revoke the access and lock the parameter writing channel.

[0029] Important parameters (medium protection level) include: system variables corresponding to workpiece coordinate systems G54~G59 (#5221~#5283, where a digit ending in 1 represents the X-axis value, a digit ending in 2 represents the Y-axis value, and a digit ending in 3 represents the Z-axis value); system variables corresponding to the additional workpiece coordinate systems G54.1 P1~P48 (#7001~#7943); system variables corresponding to tool length compensation parameters (#2001~#2400, where #2001~#2200 are shape compensation values, and #2201~#2400 are wear compensation values); and system variables corresponding to tool radius compensation parameters (#2401~#2800, also divided into shape compensation and wear compensation). These parameters directly determine the relative positional relationship between the tool and the workpiece during part machining and are core variables affecting machining accuracy. They are accessible to programmers and administrators. Unlocking and modification require the key switch to be in the authorized position and the corresponding user password to be entered. After unlocking, the system will automatically lock after 15 minutes of inactivity.

[0030] Standard parameters (basic protection level) include: local coordinate system variables (#5201~#5203, which are the common coordinate offset values ​​of the X, Y, and Z axes, respectively) and system variables corresponding to the temporary coordinate system G52. These parameters are temporary single-program call parameters, which are only temporarily accessible to operators. They are automatically cleared after the program execution ends to prevent residual temporary parameters from causing subsequent processing accidents.

[0031] The permission configuration for the three protection levels mentioned above is implemented as follows: First, the system parameter 3299#0 (PKY bit) is set to 1, switching the control of parameter write protection from PWE (parameter 8900#0) to PMC signal G46.0 (KEYP signal). Then, permission judgment logic is written in the PMC ladder diagram, mapping the three physical positions of the key switch on the machine tool operation panel to three user identity levels: operator (Level 1 protection), programmer (Level 2 protection), and administrator (Level 3 protection), with each identity level having an independent 6-digit numeric password. In the PMC program, when both the key position signal and the corresponding password verification pass, the PMC outputs the G46.0 signal to the CNC side, granting write permission for the corresponding level of parameters. Simultaneously, timeout monitoring logic is written in the PMC ladder diagram, utilizing the PMC's internal timer (TMR instruction). If no parameter write operation occurs within a preset time (10 minutes for core level, 15 minutes for important level) after unlocking, the permission signal is automatically reset, locking the parameter write channel.

[0032] In this embodiment, step S2 mainly utilizes the native macro program interrupt function and PMC window function of the FANUC system to construct a background-resident coordinate system parameter monitoring mechanism. At the macro program level, using system variables #3901 (setting the macro program interrupt function) and #3902 (specifying the macro program number to be called by the interrupt), a background-resident interrupt macro program (such as O9001) is configured, and the interrupt scan cycle is set to 50~200ms. The core function of this interrupt macro program is to periodically read the current values ​​of the core-level parameters and important-level parameters divided in step S1, and compare them with the preset reference values ​​in the system ROM in real time.

[0033] In practical implementation, when reading core-level parameters, the current values ​​of parameters 1815, 1240~1243, and 1320~1321 are read using the parameter read function code (function code number 17) in the PMC window. When reading important-level parameters, the system variables (#5221~#5283) corresponding to G54~G59 are read using the workpiece origin offset read function code (function code number 15), and the tool compensation system variables (#2001~#2800) are read using the tool offset read function code (function code number 13). The read command for the PMC window is WINDR (SUB51), and the write command is WINDW (SUB52). When executing window read and write commands, it is important to note that: the function code controlling the storage of the data's starting address determines the task to be completed by the window read / write; all data is stored internally in binary form within the PMC and must be used in conjunction with the NUMEB (SUB40, defining binary constants) function command.

[0034] When a change in parameter value is detected and there is no valid authorization record for the corresponding level in the current system, the interrupt macro program immediately sends an intercept trigger signal to the PMC. Upon receiving this signal, the PMC program executes the following three levels of interception actions in sequence: Level 1: Lock the system parameter write channel – disable parameter write enable from the bottom layer by resetting the G46.0 signal (KEYP signal). For methods that write directly through system variables (such as the assignment statement #5221=** in a macro program), lock the [SYSTEM] function key using parameter 3208#0 to prevent access to the coordinate system modification screen.

[0035] Level 2: Cut off the enable signals of each feed axis—send the G8.4=0 signal (emergency stop output signal) to the CNC side through the PMC program, so that the CNC immediately enters the emergency stop state and prohibits the movement of all axes. At the same time, cut off the feed enable signals of each servo axis (G130.0~G130.7 correspond to the feed enable of axes 1 to 8).

[0036] Level 3: Suspend the execution of all current machining programs and trigger a system-defined alarm. In the PMC ladder diagram, use the information display function command DISP (SUB41) to display the customized alarm message ALM-1001 "Unauthorized modification of coordinate system, operation blocked" on the system screen, informing the operator of the reason for the blocking.

[0037] Through the above three-level interception mechanism, a complete protection chain is built from three levels: parameter writing prohibition, axis motion cut-off, and program execution suspension. This fundamentally prevents unauthorized modifications of coordinate system parameters from taking effect, ensuring the safety of machine tools and workpieces.

[0038] In this embodiment, step S3 mainly includes two aspects: 1. graded early warning and machine locking mechanism; 2. automatic backup and one-click recovery mechanism.

[0039] Among them, the tiered early warning and device locking mechanism triggers differentiated early warning and handling mechanisms based on the security level of the modified parameters: For abnormal modifications to ordinary parameters (such as unauthorized modifications to local coordinate system variables #5201~#5203), since the impact of such parameters is limited, a prompt message box will only pop up on the system panel (using the DISP command to display the prompt: local coordinate system parameters have been changed), without triggering machine lockout or alarms, and without affecting the normal operation of the program.

[0040] For any abnormal modification of critical parameters (such as unauthorized modification of workpiece coordinate system variables G54~G59 or tool compensation parameters), the three-level interception mechanism in step S2 above will be immediately triggered. The system will alarm and lock the feed axis, preventing the machining program from starting. Only users with programmer or administrator privileges can unlock the program after entering the correct password.

[0041] For abnormal modifications to core parameters (such as unauthorized modifications to machine origin setting parameters 1815#4 / #5 or reference point limit parameters 1320~1321), the machine tool will be immediately locked in an emergency stop (G8.4=0), the spindle enable and all servo axis enable will be cut off, and the highest level alarm will be triggered. Only the highest-level administrator can unlock and restore the machine after completing password verification and operation confirmation. At the same time, the system will require manual verification of the modified core parameters (such as performing a reference point return operation to verify the correctness of the parameters) before normal machining can be started.

[0042] The automatic backup and one-click restore mechanism ensures that the system automatically performs the following backup process each time an authorized user modifies coordinate system parameters or tool compensation parameters and presses the confirmation and save button: First, by using the parameter reading function code (17), workpiece origin offset reading function code (15), and tool offset reading function code (13) in the PMC window, the complete values ​​of all current core-level parameters, important-level parameters, and ordinary-level parameters are read in sequence.

[0043] Secondly, the read data is packaged in the following structured format: backup file header (including backup identifier, timestamp, operator number, and backup trigger reason), core parameter block (including complete values ​​of parameters such as 1815, 1240~1243, and 1320~1321), important parameter block (including complete values ​​of G54~G59 corresponding to #5221~#5283 and tool compensation #2001~#2800), and backup file tail (including data checksum).

[0044] Then, the packaged data is used to generate an encrypted backup file, named in the format YYYYMMDD_HHMMSS_Operator Number Backup Sequence Number.BCK. This backup file is stored in a hidden partition of the FANUC system's built-in CF card (Compact Flash card), or in the non-volatile storage area of ​​the system's FROM / SRAM. The system uses a circular storage strategy, automatically retaining no fewer than 20 recent historical backup versions. When the number of backup files exceeds a preset limit, the oldest backup file is automatically overwritten.

[0045] When parameter errors occur or system alarms require restoration, the administrator can access the coordinate system one-click restoration interface via a custom soft key on the system panel. This interface displays all historical backup files in a list format, with each item including the backup time, operator number, and backup trigger reason. After selecting the target backup file, the administrator clicks the confirm restore button. The system then uses the write parameter function code (18), write workpiece origin offset function code (16), and write tool offset function code (14) in the PMC window to sequentially write the data from the backup file into the corresponding parameter registers and system variables in batches. The restoration process is fully automated, requiring no manual input. Upon completion, an automatic pop-up window indicates that restoration is complete, and the machine tool can be used normally without restarting. This reduces abnormal downtime from several hours (requiring tool resetting and origin relocation) to less than one minute.

[0046] In this embodiment, step S4 mainly includes: writing log recording logic in the PMC ladder diagram, establishing a log data buffer using the PMC's R address area (extended relay address area) or D address area (data table address area), and recording all coordinate system-related operations in real time. The log recording operation types include: parameter viewing operations, parameter modification operations, permission verification operations (recording both success and failure), backup operations, recovery operations, and alarm clearing operations. Each operation type corresponds to a unique operation code. Specifically, each log record contains the following complete fields (see Table 1): Table 1 Log Records .

[0047] After each operation, log data is written to the system's non-volatile memory area (a designated reserved area of ​​FROM or SRAM) via the PMC's MOVW (word transfer) instruction. This area is write-protected by system hardware, and only the highest-level administrator can read the log content through a dedicated data viewing interface. No user (including the administrator) can delete or modify the recorded log data.

[0048] On the data viewing interface, administrators can search and filter logs by multiple dimensions such as time range, operator, and operation type, and export log reports to meet the requirements of the ISO9001 quality management system for production process traceability in the mechanical processing industry, which facilitates the division of responsibilities and problem review after an accident.

[0049] This invention is entirely based on the native PMC programming, macro program interrupt, system variable read / write, and parameter configuration functions of the FANUC system. It requires no external hardware installation or modification of the machine tool's electrical wiring, and the configuration cycle for a single device does not exceed 2 hours. It is compatible with the entire FANUC 0i / 16i / 18i / 21i / 30i / 31i series systems, covering over 90% of FANUC system machining centers on the market. It can be used for batch upgrades of equipment in one's own factory, and can also be used to provide technical services, technical consultation, and technology transfer to external parties.

[0050] This invention utilizes macro program interrupt functionality to achieve real-time parameter monitoring with a cycle of 50-200ms, enabling the detection and immediate interception of anomalies during operator modifications of coordinate coefficient values. Simultaneously, a triple verification mechanism—including variation amplitude verification, numerical range verification, and adjacent coordinate system comparison verification—precisely intercepts or forces secondary confirmation of abnormal value inputs, fundamentally preventing workpiece scrapping and equipment collisions caused by misoperation. Furthermore, this invention employs an automatic backup + one-click recovery mechanism, completely resolving the pain point of needing to re-set tools and find the origin after parameter mismodification. After each authorized modification, the system automatically generates an encrypted backup file with a timestamp and operator number, retaining at least 20 historical versions. In abnormal situations, full parameter recovery can be completed within one minute, reducing downtime from hours in traditional solutions to minutes, ensuring the continuity and production efficiency of batch parts processing.

[0051] For the foregoing embodiments, in order to simplify the description, they are all described as a series of actions. However, those skilled in the art should understand that this application is not limited to the described order of actions, because according to this application, some steps can be performed in other orders or simultaneously. Furthermore, those skilled in the art should also understand that the embodiments described in the specification are preferred embodiments, and the actions involved are not necessarily essential to this application.

[0052] The above embodiments describe the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Modifications and variations made by those skilled in the art without departing from the spirit and scope of the invention should be within the protection scope of the appended claims.

Claims

1. A method for protecting the FANUC coordinate system of a machining center, characterized in that, Includes the following steps: Step S1: Divide the coordinate system parameters into protection levels according to their importance, switch the parameter write protection control to the PMC signal through system parameter settings, write the permission judgment logic in the PMC ladder diagram, map the three physical positions of the key switch to three user identity levels: operator, programmer and administrator, and combine password verification to dual control the write permissions of parameters at each level. Step S2: Based on the macro program interrupt function and PMC window function, a background parameter monitoring mechanism is constructed. The current value of each level parameter is periodically read and compared with the reference value. When unauthorized modification is detected, a three-level interception action is executed in sequence: locking the parameter writing channel, cutting off the feed axis enable, pausing the machining program and triggering an alarm. Step S3: Trigger a differentiated warning and processing mechanism based on the security level of the modified parameters, and automatically perform parameter backup after authorization modification confirmation, and write back the backup data in batches through the one-click recovery interface; Step S4: Establish a log buffer in PMC to record coordinate system-related operations in real time and store them in a non-volatile area. The recorded data must not be deleted or modified.

2. The method for protecting the FANUC coordinate system of a machining center as described in claim 1, characterized in that, The protection level in step S1 specifically includes: Core-level parameters can only be unlocked and modified if both conditions are met simultaneously: the key switch is in the administrator-only position and the administrator password is entered. If no modification is performed within 10 minutes after unlocking, the privilege will be automatically revoked. Important parameters can only be unlocked and modified if both conditions are met: the key switch is in the authorized position and the corresponding user password is entered. After unlocking, the device will automatically lock if there is no operation for 15 minutes. Normal-level parameters are only temporarily accessible and are automatically cleared after program execution.

3. The method for protecting the FANUC coordinate system of a machining center as described in claim 1, characterized in that, The macro program interrupt function in step S2 is specifically configured by setting a background resident interrupt macro program through system variables, and setting the interrupt scan period to 50~200ms. The core function of the interrupt macro program is to periodically read the current values ​​of core-level parameters and important-level parameters and compare them with the preset reference values ​​in the system ROM.

4. The method for protecting the FANUC coordinate system of a machining center as described in claim 1, characterized in that, The PMC window functions in step S2 include: reading core-level parameters by reading parameter function code number, reading workpiece coordinate system variables by reading workpiece origin offset function code number, and reading tool compensation system variables by reading tool offset function code number.

5. The method for protecting the FANUC coordinate system of a machining center as described in claim 1, characterized in that, The three-level interception action in step S2 is specifically as follows: Level 1: Disable parameter writing enable from the bottom layer via the G46.0 signal, and prevent access to the coordinate system modification screen by locking the SYSTEM function key; Level 2: By sending the G8.4=0 signal, the CNC is put into emergency stop state, and the feed enable signals of each servo axis are cut off; Level 3: Pause the execution of all current processing programs and display custom alarm information on the system screen via the Information Display Function (DISP) command.

6. The method for protecting the FANUC coordinate system of a machining center as described in claim 1, characterized in that, The differentiated early warning and processing mechanism in step S3 specifically includes: For abnormal modifications to ordinary parameters, only a prompt message box will pop up on the system panel, without triggering a lockout or alarm; For any abnormal modification of critical parameters, the three-level interception mechanism in step S2 is immediately triggered. The system alarms and locks the feed axis. Only users with programmer or administrator privileges can unlock it after entering the correct password. For abnormal modifications to core parameters, the machine tool will be immediately locked and shut down, the spindle and all servo axes will be disabled, and the highest level alarm will be triggered. The machine can only be unlocked and restored after the highest administrator completes password verification and operation confirmation. Manual verification of the modified core parameters is also required.

7. The method for protecting the FANUC coordinate system of a machining center as described in claim 1, characterized in that, The automatic backup process in step S3 specifically includes: The complete values ​​of all core-level parameters, important-level parameters, and ordinary-level parameters can be read sequentially using the function code numbers for reading parameters, reading workpiece origin offset, and reading tool offset in the PMC window. The read data is packaged in a structured format that includes a backup file header, core parameter blocks, important parameter blocks, and a backup file footer; The generated encrypted backup file is stored in the hidden partition of the system's built-in CF card or in the non-volatile storage area of ​​the system's FROM / SRAM; A circular storage strategy is used to automatically retain at least 20 recent historical backup versions.

8. The method for protecting the FANUC coordinate system of a machining center as described in claim 1, characterized in that, The one-click recovery specifically refers to: entering the coordinate system one-click recovery interface through the custom soft key on the system panel. This interface displays all historical backup files in a list format, and the list items include the backup time, operator number, and backup trigger reason.

9. A method for protecting the FANUC coordinate system of a machining center as described in claim 1, characterized in that, The operations include: parameter viewing, parameter modification, permission verification, backup, recovery, and alarm cancellation. Each operation type corresponds to a unique operation code. Log data is written to the system's non-volatile storage area via the PMC's MOVW word transfer instruction. This area is write-protected by the system hardware, and only the highest-level administrator can read the log content through a dedicated data viewing interface.

10. A method for protecting the FANUC coordinate system of a machining center as described in claim 1, characterized in that, The log buffer supports log retrieval and filtering based on multiple dimensions such as time range, operator, and operation type, and also supports exporting log reports.

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