A work station interlocking control method of an automobile part feeding and discharging manipulator

Abstract

The application discloses a work station interlocking control method of an automobile part feeding and discharging manipulator, and particularly relates to the technical field of manipulator feeding and discharging control, and is used for solving the problem that in the existing multi-station feeding and discharging process of automobile parts, the manipulator only relies on the machine tool to complete signal, clamp opening and closing signal and workpiece in-place signal for sequential interlocking, and it is difficult to accurately confirm the current taking and placing boundary of the target work station. By establishing the work station state version of the target work station, locking the current work station state snapshot before the manipulator enters, judging the interlocking state according to the workpiece in-place state, clamp feedback, machine tool completion feedback, manipulator clamping feedback and last period execution record, and then generating the interlocking action strategy of the binding state version number, action type, expected feedback and prohibited repeated issuing mark, the taking and placing boundary of the target work station can be accurately confirmed, repeated issuing, empty position taking, unclamped starting and roughcast and finished product string position circulation can be avoided.

Description

Technical Field

[0001] This invention relates to the field of robotic arm loading and unloading control technology, specifically a workstation interlock control method for a robotic arm for loading and unloading automotive parts. Background Technology

[0002] In automotive parts manufacturing lines, components such as steering knuckles, brackets, housings, and connecting seats typically undergo continuous processes including blank loading, machine tool clamping, machining, finished product removal, buffer transfer, inspection transfer, and unloading. To improve production cycle time, existing production lines usually employ robotic arms in conjunction with machine tool controllers, fixture actuators, and workpiece arrival detection elements to complete loading and unloading operations. Upon receiving signals from the machine tool indicating machining completion, fixture release, and workpiece arrival, the robotic arm moves to the target station to retrieve the finished product. If it detects that the target station is empty, the fixture is in a released state, and the robotic arm is holding a blank, it places the blank into the target station. After the fixture is clamped in place, the machine tool continues its machining cycle. This method meets the requirements of conventional sequential loading and unloading and is a common interlocking control method in automated automotive parts manufacturing lines.

[0003] However, in actual production, the status of the target workstation is not always consistent with the signal of a single device. For example, after manual temporary material replenishment, the workpiece arrival detection element may show that a part is present, but the robot arm has not completed the corresponding unloading action in the previous cycle; after abnormal pause or emergency stop reset, the machine tool completion signal, fixture status, and workpiece arrival signal may still remain in the state before the reset; when there is a delay in the feedback of fixture release or clamping, the robot arm may have already reached the waiting position, but the fixture status of the target workstation has not yet stabilized; when the robot arm's gripper pressure, vacuum holding, or the record of the previous pick-and-place action changes, whether the robot arm is currently holding a blank, a finished product, or an empty clamp may also be inconsistent with the workpiece arrival status of the target workstation. All of the above situations can cause multiple source signals to conflict or have unclear relationships within the same work cycle at the target workstation.

[0004] The problem is particularly pronounced when the robotic arm needs to perform the exchange action of picking up finished products and placing blanks within the same target workstation. The exchange action requires the robotic arm to determine whether a finished product exists at the target workstation, whether it holds the blank to be placed, whether the fixture has been released, whether the machine tool has completed processing, and whether the results of the previous cycle can carry over to the current state. If interlocking is still based solely on single signals from the machine tool completion signal, fixture opening / closing signal, or workpiece arrival signal, it is difficult to accurately distinguish whether the target workstation is currently in a state of waiting to pick up finished products, placing blanks, allowing exchange, prohibiting entry, or requiring verification.

[0005] Therefore, the main problem in the existing interlock control of automotive parts robotic arms for loading and unloading is the lack of unified attribution and consistency confirmation of the multi-source field status of the same target workstation under the same operating state. When the target workstation status, machine tool processing status, fixture status, robotic arm clamping status, and the execution result of the previous cycle cannot be uniformly correlated, it can easily lead to problems such as repeated issuance of robotic arm actions, material retrieval from empty positions, starting processing before the blank is clamped, and misplacement of finished products and blanks, affecting the stability of continuous loading and unloading operations and the traceability of the field status. Summary of the Invention

[0006] To address the shortcomings of existing technologies, this invention provides a workstation interlock control method for an automotive parts loading and unloading robot, thereby solving the problems mentioned in the background section.

[0007] To achieve the above objectives, the present invention provides the following technical solution:

[0008] A method for interlocking control of workstations in a robotic arm for loading and unloading automotive parts includes:

[0009] S1. Establish a workstation status version with a status version number for the target workstation, and record the workstation number, component type, workstation occupancy status, fixture opening / closing status, machine tool processing status, robot gripping status, and abnormal reset flag.

[0010] S2. Before the robot enters the target station, read the workpiece's position status, fixture feedback, machine tool completion feedback, robot gripping feedback, and the previous cycle execution record, and lock the current station status snapshot.

[0011] S3. Determine the interlock status based on the current workstation status snapshot. The interlock status includes allowing finished product to be picked up, allowing blank to be placed, prohibiting entry, and pending verification. When registering the finished product temporary storage clamping position and blank clamping position in the equipment layout table, it also includes allowing exchange.

[0012] S4. Generate interlock action strategy based on interlock status, and bind workstation number, status version number, action type, clamping expectation, arrival expectation, fixture expectation, and prohibit repeated issuance mark;

[0013] S5. Execute the corresponding action according to the interlock action strategy. The action exchange is based on the finished product temporary storage clamping position and blank clamping position registered in the equipment layout table. Collect robot arm positioning feedback, clamping feedback, workpiece positioning feedback, fixture clamping feedback, and robot arm exit feedback.

[0014] S6. Based on the collected feedback, write back the workstation status version. If the feedback meets expectations, form the workstation allowable status for the next cycle. If the feedback does not meet expectations, retain the original status version number, write the pending review status, and lock the prohibition of repeated issuance flag corresponding to the status version number. Under the locked status, it is not allowed to submit the same action again based on the original interlock action strategy. When the field content changes, generate a new workstation status version, retain the old version, and re-form the current workstation status snapshot, interlock status record, and interlock action strategy based on the new workstation status version before unlocking.

[0015] Furthermore, S1 includes:

[0016] The production line controller will record the status version of the same target workstation as an incremental record, which is generated by submitting the file once.

[0017] Generate a status version number using workstation number, submission time, and incrementing sequence number;

[0018] Organize the filing fields in the following order: source reading, time alignment, switch quantity debouncing, field comparison, missing data completion, and version submission;

[0019] Workstation number, component type, and abnormal reset mark are not automatically filled in;

[0020] When a field source is missing, the entry is moved to "pending supplementation"; when a field source conflicts, the entry is moved to "pending verification".

[0021] Furthermore, S2 includes:

[0022] The production line controller uses the time period from the moment the robot controller generates the pre-entry read request to the moment the current workstation status snapshot is written as the confirmation period.

[0023] Read in the following order: workpiece arrival status, fixture feedback, machine tool completion feedback, robot gripping feedback, and previous cycle execution record;

[0024] The read results will be assigned to the same target workstation and the same status version number.

[0025] The workpiece's arrival status is not updated based on the previous cycle's execution record;

[0026] If the status version number cannot be inherited, stop locking the current workstation status snapshot and write the reason to be verified.

[0027] Furthermore, S3 includes:

[0028] The production line controller determines the interlock status based on a snapshot of the current workstation status.

[0029] First check the conditions to be reviewed, then check the conditions prohibiting entry, and then check the conditions for allowing exchange, allowing the removal of finished products, and allowing the placement of blanks.

[0030] Only one interlock state is written under the same target workstation and the same state version number.

[0031] Furthermore, S3 also includes:

[0032] The current workstation status snapshot references a workstation status version that can be traced back to the previous cycle execution record, and there are no unclosed pick-and-place records for the same target workstation between the two;

[0033] The previous cycle execution record points to the same target workstation. The workpiece is in position, the fixture feedback is released and in position, the machine tool completion feedback is completed, and the robot gripping feedback is holding the blank. When the equipment layout table registers the finished product temporary storage clamping position and the blank gripping position, the production line controller writes the interlock status to allow exchange.

[0034] Furthermore, S4 includes:

[0035] After the production line controller verifies that the interlock status record, the current workstation status snapshot, and the status version number in the workstation status version are all consistent, it forms an interlock action strategy when the interlock status is allowed to pick up finished products, allowed to put in blanks, or allowed to exchange.

[0036] When the interlock status is "Entry Prohibited" or "Pending Review", the interlock action strategy is not generated.

[0037] The tag that prohibits duplicate issuance is generated by the workstation number, status version number, and action type.

[0038] Furthermore, S5 includes:

[0039] The production line controller uses the time from when it submits the interlock action strategy to the robot controller to when the robot exits and the feedback is written to the workstation status database as the execution confirmation period.

[0040] Before submission, the system searches the workstation status database for the same "Do Not Duplicate Issuance" flag. If there are actions that have not yet been written into the execution feedback record, the system will not submit again.

[0041] The robot arm is controlled to perform the corresponding action according to the action type in the interlock action strategy, and the robot arm positioning feedback, clamping feedback, workpiece positioning feedback, fixture clamping feedback, and robot arm exit feedback are written into the execution feedback record.

[0042] Furthermore, S6 includes:

[0043] The production line controller verifies that the workstation number, status version number, and prohibition of repeated issuance mark in the execution feedback record and interlock action strategy are consistent, and that the clamping feedback meets the clamping expectation, the workpiece arrival feedback meets the arrival expectation, the fixture clamping feedback meets the fixture expectation, the robot arrival feedback is in place, and the robot exit feedback is exited. When these conditions are met, a new workstation status version is formed and written into the workstation allowable status for the next cycle.

[0044] Furthermore, S6 also includes:

[0045] If the clamping feedback does not meet the clamping expectation, the workpiece positioning feedback does not meet the positioning expectation, the fixture clamping feedback does not meet the fixture expectation, the robot positioning feedback is not in position, the robot exit feedback is not exited, or the execution feedback record is missing, any of the following situations are met: robot positioning feedback, clamping feedback, workpiece positioning feedback, fixture clamping feedback, or robot exit feedback.

[0046] The production line controller writes a pending review status under the same workstation number and the same status version number, and keeps the "Do Not Repeatedly Issue" flag corresponding to the same workstation number, the same status version number, and the same action type locked.

[0047] Compared with the prior art, the present invention has the following beneficial effects:

[0048] 1. By establishing a station status version for the target station, a snapshot of the current station status is locked before the robot enters the target station. Based on the workpiece arrival status, fixture feedback, machine tool completion feedback, robot gripping feedback, and the previous cycle execution record, the interlock status is determined to allow picking up finished products, placing blanks, exchanging, prohibiting entry, or pending verification. Then, an interlock action strategy is generated that binds the station number, status version number, action type, gripping expectation, arrival expectation, fixture expectation, and prohibits repeated issuance. This achieves the goal of confirming the actual picking and placing boundaries of the target station under the same station status version, avoiding problems such as repeated issuance, empty picking, unclamped start, and blank and finished product misplacement after manual material replenishment, abnormal pause and reset, fixture feedback delay, or changes in robot gripping status.

[0049] 2. By collecting feedback on robot arm positioning, clamping, workpiece positioning, fixture clamping, and robot arm exit after the robot arm performs actions such as picking up finished products, placing blanks, and exchanging, and writing back the station status version based on the correspondence between the collected feedback and the clamping, positioning, and fixture expectations, the station status is set up for the next cycle when the feedback is satisfied. If the feedback is not satisfied, the station status is set to pending review and the same status version is prohibited from being issued repeatedly. This achieves a traceable closed loop between the robot arm loading and unloading actions, the target station status, and the status for the next cycle, reducing the risk of continuous operation caused by short-term signal conflicts, inconsistent status after reset, or incomplete execution results. Attached Figure Description

[0050] Figure 1 A schematic diagram of the overall process from workstation status version to write-back closed loop;

[0051] Figure 2 A diagram illustrating the creation and field organization of workstation status versions;

[0052] Figure 3This is a diagram illustrating the pre-entry reading and current workstation status snapshot locking.

[0053] Figure 4 This is a schematic diagram illustrating the interlock state determination and unique write operation.

[0054] Figure 5 A diagram illustrating the allowed exchange conditions;

[0055] Figure 6 A schematic diagram illustrating the generation of interlock action strategies and the prevention of duplicate issuance of markers;

[0056] Figure 7 This is a schematic diagram illustrating the execution and feedback collection of interlocking actions.

[0057] Figure 8 This is a closed-loop diagram illustrating the feedback comparison and workstation status version write-back. Detailed Implementation

[0058] 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. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0059] Example: Combined with Appendix Figures 1-8 This embodiment provides a workstation interlock control method for an automotive parts loading and unloading robot, including:

[0060] S1. Establish a workstation status version for the target workstation, recording the workstation number, part type, workstation occupancy status, fixture opening / closing status, machine tool processing status, robot gripping status, and abnormal reset flag. The specific implementation is as follows:

[0061] The production line controller generates a workstation status version during the preparation stage for loading and unloading operations at the target workstation. The target workstation is a fixed location on the automotive parts processing line where robotic arms are allowed to perform pick-and-place actions and where there is a registered relationship with the machine tool's processing status. This location must include at least a machine tool fixture position. Buffer positions, inspection transfer positions, and unloading positions are included in this method after their corresponding machine tool fixture positions and status relationships are registered in the equipment layout table. The workstation status version is an incremental record generated in a single filing submission for the same target workstation, determined by the workstation number, submission time, and incrementing sequence number. The status version number is a unique identifier for the workstation status version, and old records are not overwritten by new records.

[0062] The production line controller reads the filing fields from the equipment layout sheet, production task sheet, material tray scanning record, fixture configuration record, machine tool controller, fixture detection element, robot controller, and manual reset record area, and organizes them in the following order: source reading, time alignment, switch quantity debouncing, field comparison, missing data completion, and version submission. Time alignment is based on the current filing submission time of the same target workstation. Fields within the range of the most recent valid record before the submission time are not included in this filing. Switch quantity debouncing is confirmed only after continuous validity. Missing data completion is only allowed to complete the workstation occupancy status, fixture opening / closing status, machine tool processing status, and robot gripping status that have not changed in the previous workstation status version and whose source equipment is not offline. Workstation number, part type, and abnormal reset mark are not allowed to be automatically completed.

[0063] In this implementation, the empty clamp boundary, clamping pressure boundary range, insufficient air pressure boundary, insufficient hydraulic pressure boundary, detection element de-jittering holding time, fixture holding time, and robot arm clamping holding time are all read from the equipment parameter table. The equipment parameter table is bound and saved with the workstation number, component type, fixture type, and robot arm end effector type. When the production line controller generates workstation status versions, current workstation status snapshots, interlock status records, interlock action strategies, execution feedback records, and write-back records, it also records the version of the equipment parameter table used. If the equipment parameter table is missing, the equipment parameter table version does not match the target workstation, or the boundary values ​​in the equipment parameter table are empty, default values ​​are not used to fill in the missing values, and the corresponding target workstation is transferred to pending verification.

[0064] The workstation number is a fixed identifier for the target workstation in the production line layout. It is obtained by organizing the machine tool address, fixture address, and buffer address in the equipment layout table. When creating a file, the device address pointed to by the current task is read first, and then compared with the equipment layout table. If the address is uniquely matched, the workstation number is written. If the address is missing, duplicated, or not registered in the equipment layout table, no workstation status version is generated, and the file is transferred to pending supplementation.

[0065] The part type is the name of the automotive part process object undertaken by the current target workstation, which is jointly confirmed by the production task sheet, the material tray scanning record, and the fixture configuration record. When creating the file, first read the part name in the production task sheet, then read the material name in the material tray scanning record, and then check the part names that are allowed to be undertaken in the fixture configuration record. If the three are consistent, write the part type. If the material tray is not scanned, it is transferred to the pending entry. If the three are inconsistent in name or the fixture is mismatched, it is transferred to the pending verification. No single record can replace the other records.

[0066] The workstation occupancy status is the current status of the workpiece being carried at the target workstation. The values ​​are limited to "workpiece present", "workpiece absent", and "status unknown". It is obtained by combining the workpiece arrival detection element, the fixture support surface detection element, and the previous manual confirmation record. When both detection elements indicate the presence of a workpiece after debouncing, "workpiece present" is written. When both indicate the absence of a workpiece, "workpiece absent" is written. When the two detection elements conflict, or when the manual confirmation record is later than the change in the detection elements and does not explain the source of the pick-up or placement, "status unknown" is written.

[0067] The clamp opening / closing state refers to the constraint position of the clamp on the workpiece at the target station. The values ​​are limited to "loose", "clamped", "intermediate", and "unknown". The state is obtained by recording the clamp release position detection element, clamp clamp position detection element, and clamp drive valve. "Loose" is written when only "loose" is valid, "clamped" is written when only "clamped" is valid, "intermediate" is written when both "loose" and "clamped" are invalid and the drive valve is in the action holding state, and "unknown" is written when both "loose" and "clamped" are valid, the detection line is disconnected, the air pressure is insufficient, the hydraulic pressure is insufficient, or the drive valve record is missing.

[0068] The machine tool processing status is the process stage of the current part on the machine tool corresponding to the target workstation. The values ​​are limited to pending processing, processing, processing completed, interrupted and reset, and status unknown. It is obtained by organizing the machine tool cycle status, processing completed position, paused position, and reset position. When the cycle status is not started and no reset record appears, it is written as pending processing. When the cycle status is running, it is written as processing. When the processing completed position is valid and no reset record appears later than the processing completed position, it is written as processing completed. When the emergency stop release, pause resumption, or manual reset record is later than the previous workstation status version, it is written as interrupted and reset. When the machine tool is offline or the cycle status conflicts with the processing completed position, it is written as status unknown.

[0069] The gripping state of the robot arm refers to the current state of the workpiece held by the end effector of the robot arm. The values ​​are limited to empty grip, holding blank, holding finished product, and gripping unknown. It is obtained by compiling the current program segment of the robot arm controller, gripper opening and closing detection, gripping pressure record, vacuum holding record, and the record of the last pick-and-place action. When the gripper is in the open confirmation state and the gripping pressure is lower than the empty gripping boundary, it is written as empty gripping. When the gripping signal is stable and the record of the last pick-and-place action points to the source of blank, it is written as holding blank. When the gripping signal is stable and the record of the last pick-and-place action points to the source of finished product, it is written as holding finished product. When the gripping pressure is in the boundary range, the vacuum holding is insufficient, or the record of the last pick-and-place action is missing, it is written as gripping unknown.

[0070] The abnormal reset flag indicates whether the target workstation experienced a pause, emergency stop, manual release, or recovery record after manual intervention before this filing. The value is limited to "yes" or "no". It is compiled from emergency stop circuit records, machine tool pause records, robot alarm reset records, and operator confirmation records. If there is a recovery record that is later than the previous workstation status version and points to the same target workstation, "yes" is written. If no such recovery record is found, "no" is written. If there is only a whole line recovery record and it does not point to a specific target workstation, it will not be automatically assigned to a target workstation, and the corresponding target workstation will be transferred to pending verification.

[0071] After the above fields are confirmed, the production line controller will use the workstation number as the attribution key and write the part type, workstation occupancy status, fixture opening and closing status, machine tool processing status, robot gripping status, abnormal reset flag, source address, and recording time into the workstation status database. When the same workstation submits the same field content repeatedly within the same submission time, a new version will not be generated, but only the duplicate submission trace will be added. When the field content changes, a new workstation status version will be generated, and the old version will be retained.

[0072] "Pending supplementation" indicates that the source of the field is missing, making it impossible to create a file; "Pending verification" indicates that the source of the field exists but they conflict with each other, making it impossible to confirm. Neither "Pending supplementation" nor "Pending verification" will trigger the robot to enter the target workstation.

[0073] The workstation status database provides the next stage with workstation number, component type, workstation occupancy status, fixture opening / closing status, machine tool processing status, robot gripping status, abnormal reset flag, status version number, and recording time, and returns a successful entry flag, a pending entry flag, and a pending verification reason.

[0074] This step only reads and records on-site records related to the robot arm, machine tool, fixture, tray, and manual reset. It does not change the machine tool's operating status, trigger robot arm actions, or bypass emergency stop circuits and protective door interlocks. When implementing this, any traceable record area in the production line controller register area, edge controller status table, or industrial database can be used. The workpiece arrival detection element can be a proximity switch, photoelectric switch, or vision arrival detection. As long as the above-mentioned field closed set can be formed and the workstation status version is kept updated, it is considered an equivalent implementation.

[0075] Preferably, a steering knuckle processing line includes two machine tool fixture positions, one buffer position, and one 6-axis robot. The station number uses a letter followed by two digits. The workpiece arrival detection de-jitter time is set to 200 milliseconds, the fixture opening / closing status confirmation and holding time is set to 300 milliseconds, the upper limit of the machine tool processing status reading delay is set to 500 milliseconds, the robot gripping status confirmation and holding time is set to 300 milliseconds, the single target station file creation and submission time is set to 1 second, the repeated submission interval for the same station is set to 100 milliseconds, the number of consecutive retries is set to 2, and the retry interval is set to 200 milliseconds. For example, the production task order for station A01 records... Record the left steering knuckle blank, scan the barcode on the material tray to record the left steering knuckle blank, configure the fixture to accept the left steering knuckle blank, detect the workpiece arrival as "no part", confirm the fixture release is effective, the machine tool status is "waiting to process", the robot gripping signal is stable and the previous pick-up and put-out action record points to the source of the blank, and the emergency stop circuit does not generate a recovery record later than the previous station status version. Then, a station status version is formed with station number A01, part type "left steering knuckle blank", station occupancy status "no part", fixture opening / closing status "released", machine tool processing status "waiting to process", robot gripping status "holding blank", and no abnormal reset mark. This is written to the station status library for the next stage to read.

[0076] S2. Before the robot arm enters the target station, read the workpiece arrival status, fixture feedback, machine tool completion feedback, robot arm gripping feedback, and the previous cycle execution record of the target station, and lock the current station status snapshot. The specific implementation is as follows:

[0077] When the robot arm is in a waiting position outside the target workstation, the production line controller initiates a pre-entry read and locks the read result as a snapshot of the current workstation status. This action inherits the workstation status version formed in the previous step and occurs before the robot arm enters the target workstation. The execution entity is the production line controller, and the field sources include the workpiece arrival detection element, fixture detection element, machine tool controller, robot arm controller, and the previous cycle execution record in the workstation status database. The confirmation period starts from the moment the robot arm controller generates the pre-entry read request and ends at the moment the current workstation status snapshot is written to the workstation status database. Field change records earlier than the confirmation period and field change records later than the snapshot writing time are not included in this current workstation status snapshot.

[0078] The workpiece arrival status is the on-site result of whether there are any parts on the bearing surface of the target station. The value is limited to "present", "absent", or "unknown". It comes from the workpiece arrival detection element and the fixture support surface detection element. The production line controller first reads the holding signal of the workpiece arrival detection element, then reads the holding signal of the fixture support surface detection element, and then merges the two holding signals into the same confirmation period. When both holding signals indicate the presence of a part, it is recorded as "present". When both holding signals indicate the absence of a part, it is recorded as "absent". If the two holding signals conflict, either holding signal repeatedly changes within the confirmation period, or either detection element is disconnected, it is recorded as "unknown". The workpiece arrival status is not supplemented based on the previous cycle execution record.

[0079] The fixture feedback is the result of the fixture holding position before the robot enters the target workstation. The value is limited to loosened position, clamped position, intermediate holding, and unknown status. It comes from the fixture loosened position detection element, the fixture clamped position detection element, and the fixture drive valve holding record. The production line controller first reads the fixture loosened position detection element, then reads the fixture clamped position detection element, and then reads the fixture drive valve holding record. When only the loosened position detection element is effective, it is recorded as loosened position. When only the clamped position detection element is effective, it is recorded as clamped position. When both position detection elements are ineffective and the fixture drive valve is in the action holding state, it is recorded as intermediate holding. When both position detection elements are effective at the same time, the fixture drive valve holding record is missing, or the air pressure or hydraulic pressure is insufficient, it is recorded as unknown status.

[0080] The machine tool completion feedback is the completion and holding result of the machine tool corresponding to the target station in the current part processing cycle. The value is limited to completed, incomplete, reset after completion, and unknown status. It comes from the machining completion bit, cycle status bit, pause bit, and reset bit of the machine tool controller. The production line controller first reads the machining completion bit, then reads the cycle status bit, and then reads the most recently held record of the pause bit and reset bit. When the machining completion bit is valid and the cycle status bit shows stop, it is recorded as completed. When the machining completion bit is invalid and the cycle status bit shows running or waiting to start, it is recorded as incomplete. When a reset bit or pause recovery record appears after the machining completion bit is valid, it is recorded as reset after completion. When the machine tool is offline or the machining completion bit and cycle status bit conflict, it is recorded as unknown status.

[0081] The gripper gripping feedback is the result of the robot's end effector holding the parts before entering the target workstation. The values ​​are limited to empty grip, holding blank, holding finished product, and gripping unknown. It is derived from the current program segment of the robot controller, gripper opening and closing detection, gripping pressure record, vacuum holding record, and the previous pick-and-place action record. The production line controller first reads the current program segment of the robot controller, then reads the gripper opening and closing detection and gripping pressure record, and then reads the vacuum holding record and the previous pick-and-place action record. When the gripper is confirmed to be open and the gripping pressure is lower than the empty gripping boundary, it is recorded as empty gripping. When the gripping is effective and the previous pick-and-place action record points to the source of the blank, it is recorded as holding blank. When the gripping is effective and the previous pick-and-place action record points to the source of the finished product, it is recorded as holding finished product. When the gripping pressure is in the boundary range, the vacuum holding is insufficient, or the previous pick-and-place action record is missing, it is recorded as gripping unknown.

[0082] The previous cycle execution record is the record written to the workstation status database after the most recent robot arm pick-up and place-down action for the same target workstation. The content includes the status version number, target workstation, executed action, execution end time, workpiece arrival result, fixture holding result, and robot arm gripping result. When the production line controller reads the previous cycle execution record, it first checks whether the target workstation is consistent, then checks whether the status version number inherits the workstation status version formed in the previous step, and then checks whether the execution end time is earlier than the start of the current confirmation period. If the target workstation is inconsistent, the status version number is broken, or the execution end time is later than the start of the current confirmation period, the previous cycle execution record will not be included in the current workstation status snapshot, and the record will be written as discontinuous in the current record reading. When the target workstation is put into continuous loading and unloading operation for the first time, the workstation status version formed in the previous step is used as the basis for inheriting the previous cycle execution record, and the first inheritance record is written to the workstation status database. The first inheritance record does not record that the robot arm has completed the pick-up and place-down action.

[0083] When locking the current workstation status snapshot, the production line controller reads the data in the following order: workpiece arrival status, fixture feedback, machine tool completion feedback, robot gripping feedback, and the previous cycle execution record. It assigns each record to the same target workstation and the same status version number, and writes the target workstation, status version number, workpiece arrival status, fixture feedback, machine tool completion feedback, robot gripping feedback, previous cycle execution record reference number, and locking time. If any of the workpiece arrival status, fixture feedback, machine tool completion feedback, or robot gripping feedback is in an unclear state, the current workstation status snapshot remains locked with its original value for the next stage to read. If the target workstation cannot be confirmed, the status version number cannot be inherited, or the previous cycle execution record is discontinuous and lacks a first-time inheritance record, the current workstation status snapshot locking is stopped, a reason to be investigated is written, and the robot is not triggered to enter the target workstation.

[0084] When the same target workstation is read repeatedly under the same status version number and the field content is consistent, the first lock record is retained and the repeated read trace is added; when the field content changes, the locked snapshot is not overwritten, a new current workstation status snapshot is formed and the source of the change is retained.

[0085] This step only completes the reading before the robot enters and locks the current workstation status snapshot. It does not change the machine tool's operating status, the fixture position, issue robot pick-up and put-down actions, or release the emergency stop circuit and protective door interlock. When implemented, the workpiece's position status can be formed by proximity switch, photoelectric switch, or vision positioning detection. Fixture feedback can be formed by pneumatic fixture, hydraulic fixture, or servo fixture positioning detection. Robot gripping feedback can be formed by one of the following on-site quantities: gripper pressure, vacuum holding, or servo torque. As long as the current workstation status snapshot can be locked according to the above value set and the record is kept, it is considered an equivalent implementation.

[0086] Preferably, for a certain steering knuckle processing line, the target station A01 has a 500-millisecond confirmation period before the robot enters, the workpiece arrival detection is confirmed after 200 milliseconds, the fixture feedback is confirmed after 300 milliseconds, the upper limit of the machine tool completion feedback reading delay is 500 milliseconds, the robot gripping feedback is confirmed after 300 milliseconds, the current station status snapshot writing time does not exceed 1 second, the repeated reading interval under the same status version number is set to 100 milliseconds, the number of consecutive retries is set to 2, and the retry interval is set to 200 milliseconds; for example, if the workpiece arrival status of A01 is "no part", the fixture feedback is "released and in place", the machine tool completion feedback is "not completed", and the robot gripping feedback is "holding blank", and the target station of the previous cycle execution record is A01 and the status version number is consecutive, then the current station status snapshot containing the above fields is locked and written to the station status database for the next stage to read.

[0087] S3. Determine the interlock status based on the current workstation status snapshot. Interlock status includes: allowed to retrieve finished products, allowed to place blanks, prohibited from entering, pending verification. When registering the finished product temporary storage clamping position and blank clamping position in the equipment layout table, it includes allowing exchange. The specific implementation is as follows:

[0088] After the production line controller writes the current workstation status snapshot into the workstation status database, it determines the interlock status of the target workstation based on the current workstation status snapshot. This determination occurs during the waiting phase before the robot arm enters the target workstation. The determination criteria are limited to the target workstation, status version number, workpiece arrival status, fixture feedback, machine tool completion feedback, robot arm gripping feedback, and previous cycle execution record in the current workstation status snapshot. It does not read on-site change records outside the confirmation period and does not replace the fields in the current workstation status snapshot with machine tool process cycle time or human experience records.

[0089] A continuous status version number indicates that the status version of the current workstation referenced by the current workstation status snapshot can be traced back to the previous cycle execution record in the workstation status database. Both point to the same target workstation, the execution end time of the previous cycle execution record is earlier than the locking time of the current workstation status snapshot, and there are no unclosed pick-and-place records for the same target workstation between them. If any of the above conditions are not met, it is recorded as a discontinuous status version number.

[0090] The interlock state is the unique state boundary of the target workstation before the robot enters under the current state version number. The values ​​are limited to: allowed to pick up finished products, allowed to place blanks, allowed to exchange, prohibited from entering, and pending verification. When the production line controller forms an interlock state, it first checks the pending verification condition, then checks the prohibited from entering condition, and then checks the conditions for allowing exchange, allowed to pick up finished products, and allowed to place blanks. Only one interlock state is written for the same target workstation under the same state version number. If the previous condition has been met, it will not be modified for subsequent conditions.

[0091] The production line controller allows the target station to retrieve finished products if there are completed parts but the robot arm is not holding any parts. When the workpiece is in position (part present), the fixture feedback is "released and in position," the machine tool completion feedback is "complete," the robot arm gripping feedback is "empty grip," the previous cycle execution record points to the same target station with consecutive status version numbers, and the previous cycle execution record indicates that the target station has completed the processing after accepting the blank, the production line controller will determine that the target station is allowed to retrieve finished products. If the robot arm gripping feedback is not "empty grip," the fixture feedback is not "released and in position," the machine tool completion feedback is not "complete," or the previous cycle execution record does not indicate that any of the processing acceptance relationships are met, the "retrieve finished products" status will not be entered.

[0092] The production line controller determines that the target station is allowed to place a blank if the workpiece is empty and the robot arm is holding the blank. When the workpiece is in position (no workpiece), the fixture feedback is "released and in position," the machine tool completion feedback is "not completed," the robot arm gripping feedback is "holding blank," the previous cycle execution record points to the same target station, and the status version number is continuous, the production line controller will determine that the target station is allowed to place a blank. If any of the following conditions are met: the workpiece is in position (workpiece present), the fixture feedback is not "released and in position," the robot arm gripping feedback is not "holding blank," or the status version number is not continuous, the "allow to place a blank" status will not be written.

[0093] Exchange is permitted when the target workstation contains a completed part and the robot arm is capable of placing a blank. This exchange only applies to production lines where the equipment layout table has registered that the robot arm end effector has both a finished product storage gripper and a blank holding gripper. The finished product storage gripper is a physical gripping position on the robot arm end effector that allows temporary storage and retrieval of the finished product before leaving the target workstation. The blank holding gripper is a physical gripping position on the robot arm end effector that allows holding the blank during the same entry into the target workstation. Both are confirmed by the robot arm controller's gripper address and the fixture opening / closing detection record. When the workpiece is in position (part present), the fixture feedback is "released," the machine tool completion feedback is "complete," the robot arm gripping feedback is "holding blank," the previous cycle execution record points to the same target workstation with consecutive status version numbers, and the equipment layout table registers both physical gripping positions, the production line controller determines that the target workstation is eligible for exchange. If the above physical gripping positions are not registered, even if the field fields meet the above conditions, exchange will not be permitted.

[0094] Entry is prohibited when the snapshot field of the current workstation status is clearly defined, but the robot arm is prohibited from entering the target workstation's on-site status. When the fixture feedback is "clamped in place", "held in the middle", "workpiece in place" and "machine tool completed" feedback is "not completed", "robot arm holding finished product" and "workpiece in place" status, or "robot arm holding blank" and "workpiece in place" status, and "machine tool completed" feedback is "not completed", entry is prohibited. When the conditions to be reviewed are not met and the conditions for picking up finished products, placing blanks, and exchanging are all not met, entry is also prohibited, so that the clearly defined status that does not meet the allowed conditions has a unique attribute.

[0095] If the snapshot of the current workstation status to be reviewed cannot support a unique on-site status for judgment; when the workpiece arrival status is unknown, the fixture feedback is unknown, the machine tool completion feedback is unknown, the robot gripping feedback is unknown, the machine tool completion feedback is reset after completion, the status version number is discontinuous, the previous cycle execution record is missing and there is no first acceptance record, the production line controller will determine the target workstation as pending review and record the field name, field value and current status version number that caused the pending review.

[0096] After completing the interlock status determination, the production line controller writes the target workstation, status version number, current workstation status snapshot reference number, interlock status, determination basis field, and determination time into the interlock status record area of ​​the workstation status library. When the same target workstation is repeatedly determined under the same status version number and the current workstation status snapshot has not changed, the first interlock status record is retained and the repeated determination trace is added. When a new current workstation status snapshot has been formed, an interlock status record is formed separately based on the new current workstation status snapshot, without overwriting the old record.

[0097] This step only determines the interlock status, does not form an interlock action strategy, does not trigger the robot to enter the target workstation, does not change the fixture position, does not change the machine tool's operating status, and does not release the emergency stop circuit and the protective door interlock. When the interlock status is pending verification or prohibited from entering, subsequent steps can only read the interlock status record and must not rewrite it to allow picking up finished products, allow placing blanks, or allow exchange under the same status version number.

[0098] In practice, the interlock status determination can be completed in any traceable record area of ​​the production line controller register area, the edge controller status table, or the industrial database. As long as the determination basis is limited to the current workstation status snapshot and the unique interlock status is written according to the above value set, it is considered an equivalent implementation.

[0099] Preferably, a steering knuckle processing line is equipped with two machine tool fixture positions, one buffer position, and one 6-axis robot with a dual-grip end effector. The interlock status determination time can be set to no more than 200 milliseconds, the repeated determination interval under the same status version number can be set to 100 milliseconds, the number of consecutive retries can be set to 2, and the retry interval can be set to 200 milliseconds. For example, if the current status snapshot of the target station A01 shows that the workpiece is in place, the fixture feedback is released and in place, the machine tool completion feedback is completed, and the robot gripping feedback is holding the blank, the previous cycle execution record points to A01 and the status version number is continuous, and the equipment layout table registers that the robot end effector has a finished product temporary storage clamping position and a blank gripping position, then the target station A01 is determined to be allowed to exchange, and the interlock status is written into the station status database for the next stage to read.

[0100] S4. Generate interlock action strategies based on interlock status. The interlock action strategies are bound to workstation number, status version number, action type, clamping expectation, arrival expectation, fixture expectation, and prohibition of duplicate issuance flag. The specific implementation is as follows:

[0101] After the interlock status record is written into the workstation status database, the production line controller generates an interlock action strategy based on the interlock status. This strategy is formed before the robot enters the target workstation. The formation basis is limited to the interlock status record under the same target workstation and the same status version number, the current workstation status snapshot reference number, and the interlock status judgment basis field. It does not read the real-time change records of the site that are not locked, and does not replace the interlock status record with manual remarks, machine tool cycle time, or the current position of the robot.

[0102] The interlock action strategy is an incremental strategy record that can be read by the next stage. The fields are limited to workstation number, status version number, action type, clamping expectation, arrival expectation, fixture expectation, and prohibition of repeated issuance. The interlock action strategy is formed when the interlock status allows the picking of finished products, allows the placement of blanks, or allows exchange. The interlock action strategy is not formed when the interlock status is prohibited from entering or pending review. The corresponding interlock status record is kept as the only status basis that can be read by the subsequent stage.

[0103] The workstation number follows the target workstation number in the interlock status record. The production line controller first checks whether the workstation number is consistent with the target workstation in the current workstation status snapshot reference number. If they are consistent, the interlock action strategy is written. If they are inconsistent, the strategy formation is stopped and the reason to be checked is written. The workstation number cannot be filled in by the robot waiting position, machine tool display name, or manual remarks name.

[0104] The status version number is inherited from the status version number referenced in the interlock status record. The production line controller checks that the status version number in the interlock status record, the current workstation status snapshot, and the workstation status version are consistent before writing the interlock action strategy. If any status version number is inconsistent, no interlock action strategy is formed. If an interlock action strategy with the same field content already exists under the same status version number, the first strategy record is retained and a duplicate record is added to form a trace. Only when the status version number changes is it allowed to form a new strategy record based on the new interlock status record. The old strategy record is not overwritten.

[0105] The action type is formed based on the interlock state, and the value is limited to retrieve finished product, place blank, and exchange. When the interlock state is allowed to retrieve finished product, the action type is written as retrieve finished product. When the interlock state is allowed to place blank, the action type is written as place blank. When the interlock state is allowed to exchange, the action type is written as exchange. When the interlock state is prohibited from entering or pending review, the action type is not written, and the interlock action strategy is not generated.

[0106] The clamping expectation is the clamping state that the robot end effector should reach after the interlocking action is completed. The production line controller forms this expectation based on the action type and the robot clamping feedback in the current workstation status snapshot. When the action type is to pick up the finished product, the clamping expectation is written as "holding the finished product". When the action type is to place the blank, the clamping expectation is written as "empty clamp". When the action type is to exchange, the clamping expectation is written as "holding the finished product in the temporary storage clamp position and empty clamp in the blank clamp position". This expectation is only formed when the finished product temporary storage clamp position and the blank clamp position are registered in the equipment layout table and the robot controller can read the clamping and holding records of the two clamp positions respectively. If the above physical clamping positions are not registered, the interlocking action strategy of the exchange type is not formed.

[0107] The expected arrival status is the value that the workpiece should reach at the target station after the interlock action is completed. The production line controller forms this value based on the action type and the workpiece arrival status in the current station status snapshot. When the action type is to pick up a finished product, the expected arrival status is written as "no part". When the action type is to place a blank, the expected arrival status is written as "part". When the action type is to exchange, the expected arrival status is written as "part", and the "part" corresponds to the blank placed at the target station. The retrieved finished product is not considered as the target station's arrival object.

[0108] The fixture is expected to reach the target station fixture after the interlock action is completed. The production line controller generates this state based on the action type and fixture feedback in the interlock status record. When the action type is to pick up the finished product, the fixture is expected to be written as "released in place". When the action type is to place the blank, the fixture is expected to be written as "clamped in place". When the action type is to exchange, the fixture is expected to be written as "clamped in place". If the fixture feedback in the interlock status record is not "released in place", the corresponding interlock action strategy for picking up the finished product, placing the blank, and exchanging will not be generated.

[0109] The "Do Not Repeatedly Issue" flag is formed by the workstation number, status version number, and action type. It uniquely corresponds to a type of robot action under the same target workstation and status version number. Before writing the interlock action strategy, the production line controller checks whether the same "Do Not Repeatedly Issue" flag already exists in the workstation status library. If the same flag exists and no new status version number has been formed, the same interlock action strategy will not be written again, but only a duplicate formation trace will be added. If the same flag does not exist, a new interlock action strategy will be written.

[0110] After the strategy is formed, the production line controller writes the workstation number, status version number, action type, clamping expectation, arrival expectation, fixture expectation, prohibition of repeated issuance mark, interlock status record reference number, current workstation status snapshot reference number, and formation time into the strategy record area of ​​the workstation status library for the next stage to read. This step only forms the interlock action strategy, does not change the machine tool running status, does not change the fixture position, does not trigger the robot to enter the target workstation, and does not release the emergency stop circuit and the protective door interlock.

[0111] When implemented, the interlock action strategy can be stored in the production line controller register area, the edge controller status table, or any traceable record area in the industrial database. As long as the strategy fields are limited to workstation number, status version number, action type, clamping expectation, arrival expectation, fixture expectation, and prohibition of repeated issuance flag, and are formed based on the interlock status record, it is considered an equivalent implementation.

[0112] Preferably, in a certain steering knuckle processing line, the interlock action strategy formation time can be set to no more than 200 milliseconds, the retrieval time for the same prohibition of repeated issuance of the same flag can be set to no more than 100 milliseconds, the repetition formation interval can be set to 100 milliseconds, the number of consecutive retries can be set to 2, and the retry interval can be set to 200 milliseconds. For example, if the interlock status of the target station A01 is "allowed to exchange" and the status version number is A01-20260630-008, and the equipment layout table registers that the robot end effector has a finished product temporary storage clamping position and a blank clamping position, then the production line controller forms an interlock action strategy with station number A01, status version number A01-20260630-008, action type exchange, clamping expectation is finished product temporary storage clamping position holding finished product, blank clamping position empty clamping, expected position is part present, clamp expected to be clamped in place, and prohibition of repeated issuance of the flag A01-20260630-008-exchange, and writes it into the station status library for the next stage to read.

[0113] S5. Execute the corresponding action according to the interlock action strategy. The action exchange is based on the finished product temporary storage clamping position and blank clamping position registered in the equipment layout table. Collect robot arm arrival feedback, clamping feedback, workpiece arrival feedback, fixture clamping feedback, and robot arm exit feedback. The specific implementation is as follows:

[0114] After the production line controller reads the interlock action strategy, it controls the robot to perform actions such as picking up finished products, placing blanks, and exchanging according to the interlock action strategy. During the execution confirmation period corresponding to the action, it collects robot positioning feedback, clamping feedback, workpiece positioning feedback, fixture clamping feedback, and robot exit feedback. The execution confirmation period starts from the moment when the production line controller submits the interlock action strategy to the robot controller and ends at the moment when the robot exit feedback is written into the workstation status database. The field objects are limited to the workstation number, status version number, and "do not reissue" mark bound to the interlock action strategy. The robot must not enter the target workstation based on temporary manual instructions, machine tool real-time cycle time, or unlocked field signals.

[0115] Before submitting an action, the production line controller reads the workstation number, status version number, action type, clamping expectation, arrival expectation, fixture expectation, and prohibition of duplicate issuance flag in the interlock action strategy, and checks whether there are actions with the same prohibition of duplicate issuance flag in the robot controller and workstation status database that have not yet been written into the execution feedback record. If such an action exists, the same action is not submitted again, and only the duplicate submission interception trace is recorded. If such an action does not exist and the emergency stop circuit, protective door interlock, and robot waiting position are all kept in an allowed state, the corresponding action is submitted to the robot controller.

[0116] When the action type is picking up a finished product, the robot arm moves from the waiting position to the target station bound by the interlocking action strategy, reaches the finished product gripping position after the fixture is released, the end effector closes and grips the finished product, and then moves the finished product away from the target station and exits the target station's safety zone. When the action type is placing a blank, the robot arm moves from the waiting position to the target station, reaches the blank placement position, the end effector releases the blank, causing the blank to fall onto the target station's bearing surface. After the robot arm leaves the fixture's closing interference range, the target station fixture moves according to the expected movement of the fixture in the interlocking action strategy. The robot enters the clamping and holding position, and then exits the target station safety zone. When the action type is exchange, after the robot enters the target station, it first uses the finished product temporary storage clamp to grab the finished product, and then puts the blank in the blank clamping position into the target station. After the robot leaves the clamping fixture's closed interference range, the target station fixture enters the clamping and holding position as expected in the interlocking action strategy. Then the robot exits the target station safety zone. The exchange action is only performed when the interlocking action strategy records the action type as exchange and the robot end effector registers the finished product temporary storage clamp and the blank clamping position.

[0117] The robot arm's position feedback is the confirmation result of the robot arm actually reaching the target workstation's position bound by the interlocking action strategy. The value is limited to "in position", "not in position", and "position unknown". It originates from the robot arm controller's position arrival signal, the joint servo holding signal, and the target workstation positioning confirmation signal. When the robot arm controller reaches the target workstation program point and the joint servo holds it stably, it is recorded as "in position". When it does not reach the target workstation program point, it is recorded as "not in position". When the position arrival signal conflicts with the target workstation positioning confirmation signal, it is recorded as "position unknown".

[0118] Clamping feedback is the confirmation result of the clamping status of the robot end effector after the action is completed. The values ​​are limited to empty clamp, holding blank, holding finished product, and clamping unknown. It is derived from the jaw opening and closing detection, clamping pressure record, vacuum holding record, finished product temporary storage clamping position record, and blank clamping position record. When the clamping is effective after the finished product is picked up and the clamped object comes from the target station, it is recorded as holding finished product. When the jaw is released after the blank is released and the clamping pressure is lower than the empty clamping boundary, it is recorded as empty clamp. When the finished product is held in the temporary storage clamping position and the blank clamping position is released after the exchange action, it is recorded as holding finished product. When the clamping pressure is in the boundary range, the vacuum holding is insufficient, or the clamping position record is missing, it is recorded as clamping unknown.

[0119] The workpiece arrival feedback is the confirmation result of whether there are any parts on the bearing surface after the target station has completed the action. The value is limited to "part present", "part absent", and "status unknown", and it comes from the workpiece arrival detection element and the fixture bearing surface detection element. When both detection elements indicate that there are no parts after the finished product take-up action, it is recorded as "part absent". When both detection elements indicate that there are parts after the blank placement action, it is recorded as "part present". When both detection elements indicate that there are parts after the exchange action, it is recorded as "part present". When the two detection elements conflict, the detection elements jump, or the detection line is disconnected, it is recorded as "status unknown".

[0120] The clamping feedback is the confirmation result of the clamp at the target station relative to the expected holding position after the action is completed. The value is limited to clamping in place, releasing in place, not clamped, and clamping unknown. It comes from the clamping in place detection element, the clamping releasing in place detection element, the clamping drive valve holding record, and the pneumatic and hydraulic holding record. After the finished product is picked up, the clamping releasing in place detection element is effective and the clamping drive valve is kept in the releasing position, which is recorded as releasing in place. After the blank is placed and the exchange action, the clamping in place detection element is effective and the clamping drive valve is kept in the clamping position, which is recorded as clamping in place. After the blank is placed and the exchange action, the clamping in place detection element is not effective, which is recorded as not clamping. When the clamping in place detection element, the releasing in place detection element, and the clamping drive valve holding record conflict with each other or the pneumatic and hydraulic pressure is insufficient, it is recorded as clamping unknown.

[0121] The robot arm exit feedback is the confirmation result after the robot arm leaves the target workstation safety zone. The value is limited to exited, not exited, and exit unknown. It is derived from the robot arm controller exit program point and the target workstation safety zone detection signal. When the robot arm reaches the exit program point and the target workstation safety zone detection signal shows that the robot arm has left, it is recorded as exited. When the robot arm has not reached the exit program point, it is recorded as not exited. When the exit program point and the safety zone detection signal conflict, it is recorded as exit unknown.

[0122] If an emergency stop circuit disconnects, a protective door interlock fails, or a robotic arm alarms and stops during the execution confirmation period, the production line controller will stop submitting action segments, retain the feedback values ​​that have already been formed, and write the feedback values ​​that have not been formed into unknown categories according to the corresponding closed set, without automatically filling them in according to the expectations in the interlock action strategy.

[0123] After the above feedback collection is completed, the production line controller writes the workstation number, status version number, action type, prohibition of duplicate issuance mark, robot arm arrival feedback, clamping feedback, workpiece arrival feedback, fixture clamping feedback, robot arm exit feedback, and collection time into the execution feedback record area of ​​the workstation status library for the next stage to read. If an execution feedback record already exists under the same prohibition of duplicate issuance mark, the old record is not overwritten, but only duplicate collection traces are added. A new execution feedback record is formed only after the status version number changes.

[0124] This step only controls the robotic arm to perform corresponding actions according to the interlock action strategy and collects feedback. It does not generate the next cycle workstation permission status in this step, does not overwrite the interlock action strategy, and does not release the emergency stop circuit and the protective door interlock.

[0125] In practice, the robot arm's position feedback can be generated by the robot arm controller's position arrival signal; the gripping feedback can be generated by the gripper pressure, vacuum holding, and servo force; the workpiece's position feedback can be generated by proximity switches, photoelectric switches, and vision position detection; and the fixture clamping feedback can be generated by the clamping position detection and release position detection of pneumatic fixtures, hydraulic fixtures, and servo fixtures. As long as the execution feedback record can be formed according to the above value set, it is considered an equivalent implementation.

[0126] Preferably, in a certain steering knuckle processing line, the submission time for the robot arm to enter the target station can be set to no more than 100 milliseconds, the robot arm arrival feedback confirmation time can be set to 300 milliseconds, the clamping feedback confirmation time can be set to 300 milliseconds, the workpiece arrival feedback confirmation time can be set to 200 milliseconds, the fixture clamping feedback confirmation time can be set to 500 milliseconds, the robot arm exit feedback confirmation time can be set to 300 milliseconds, and the execution feedback record writing time can be set to no more than 1 second. For example, the interlock action strategy of the target station A01 records the action type as "exchange". After the robot arm enters A01, the finished product temporary storage clamping position clamps the finished product, the blank clamping position releases the blank, the workpiece arrival feedback is "workpiece present", the fixture clamping feedback is "clamped in place", and the robot arm exit feedback is "exited". Then the production line controller writes the above feedback, along with the station number A01, the status version number A01-20260630-008, and the prohibition of repeated issuance mark A01-20260630-008-exchange, into the station status database for the next stage to read.

[0127] S6. Based on the collected feedback, write back the workstation status version. If the feedback meets expectations, form the workstation's allowed status for the next cycle. If the feedback does not meet expectations, retain the original status version number, write the pending review status, and lock the "prohibit duplicate issuance" flag corresponding to that status version number. Under the locked status, it is not allowed to submit the same action again based on the original interlock action strategy. When the field content changes, generate a new workstation status version, retain the old version, and then release the lock after re-forming the current workstation status snapshot, interlock status record, and interlock action strategy based on the new workstation status version. The specific implementation is as follows:

[0128] After the production line controller writes the execution feedback record into the workstation status database, it writes back the workstation status version based on the collected feedback. This write-back action occurs after the robot performs the actions of picking up finished products, placing blanks, and exchanging them and forms an execution feedback record. The execution subject is the production line controller. It is based on the interlock action strategy and execution feedback record that is limited to the same workstation number, the same status version number, and the same prohibition of repeated issuance mark. It does not read unrecorded real-time changes on site, and does not replace the collected feedback with manual notes, machine tool cycle time, or the robot's current position.

[0129] The production line controller first reads the workstation number, status version number, action type, prohibition of duplicate issuance flag, robot arm arrival feedback, clamping feedback, workpiece arrival feedback, fixture clamping feedback, and robot arm exit feedback from the execution feedback record. Then, it reads the clamping expectation, arrival expectation, and fixture expectation from the interlocking action strategy and checks whether the workstation number, status version number, and prohibition of duplicate issuance flag in the execution feedback record are consistent with those in the interlocking action strategy. If all three are consistent, it enters the write-back process. If any one is inconsistent, it does not write back the workstation status version, writes the status to be reviewed, and records the inconsistent field name and corresponding record reference number.

[0130] Feedback meeting the clamping expectation, positioning expectation, and fixture expectation means that the clamping feedback meets the clamping expectation, the workpiece positioning feedback meets the positioning expectation, the fixture clamping feedback meets the fixture expectation, and the robot arm positioning feedback is in place and the robot arm exit feedback is exited. If the robot arm positioning feedback is not in place or positioning is unclear, or the robot arm exit feedback is not exited or exit is unclear, even if the clamping feedback, workpiece positioning feedback, and fixture clamping feedback meet the corresponding expectations, the next cycle station will not be allowed.

[0131] During the finished product retrieval operation, when the clamping expectation is "holding finished product", the workpiece arrival expectation is "no part", and the fixture expectation is "released and in place", and the execution feedback record shows "holding finished product", "workpiece arrival feedback is "no part", "fixture clamping feedback is "released and in place", "robotic arm arrival feedback is "in place", and "robotic arm exit feedback is "exited", the production line controller uses the original state version number as the preceding version to form a new workstation state version, and writes the target workstation into the workstation allowed to place blanks in the next cycle.

[0132] During the blank placement process, if the clamping expectation is empty, the workpiece arrival expectation is with a part, and the fixture expectation is clamped in place, and the execution feedback record shows that the clamping feedback is empty, the workpiece arrival feedback is with a part, the fixture clamping feedback is clamped in place, the robot arrival feedback is in place, and the robot exit feedback is exited, the production line controller will form a new workstation status version with the original status version number as the preceding version, and write the target workstation into the workstation allowed status for the next cycle of processing.

[0133] During the exchange operation, the expected clamping is that the finished product is held in the temporary storage clamping position and the blank clamping position is empty. The expected arrival is that there is a part and the expected clamping is that the fixture is clamped in place. When the clamping feedback in the execution feedback record reaches the expected clamping, it means that the clamping feedback is that the finished product is held, and the finished product temporary storage clamping position record referenced when the clamping feedback is formed indicates that the finished product is held and the blank clamping position record indicates that the blank is released. At the same time, when the workpiece arrival feedback is that there is a part, the fixture clamping feedback is that the clamping is in place, the robot arrival feedback is that it is in place, and the robot exit feedback is that it has exited, the production line controller forms a new station status version with the original status version number as the preceding version, and writes the target station into the station allowed status for processing in the next cycle.

[0134] The next cycle station's allowed status is the acceptance status written into the new station status version, with values ​​limited to allowing blank placement in the next cycle and allowing processing acceptance in the next cycle. This acceptance status only serves as the station boundary that can be read before the next current station status snapshot is locked, does not directly trigger robot arm actions, and does not replace the current station status snapshot of subsequent cycles.

[0135] Unmet feedback refers to any of the following situations: clamping feedback does not meet clamping expectations, workpiece positioning feedback does not meet positioning expectations, fixture clamping feedback does not meet fixture expectations, robot positioning feedback is not in position, robot exit feedback is not exited, or any required field is missing from the execution feedback record. When feedback is unmet, the production line controller does not generate a statement that blank placement or processing acceptance is allowed in the next cycle. Instead, it writes a pending review status under the same workstation number and the same status version number, and records the name of the unmet field, the actual feedback value, the corresponding expectation, and the execution feedback record reference number.

[0136] Prohibiting the repeated issuance of the same status version means that after the status is written for review, the production line controller will keep the "prohibit repeated issuance" flag corresponding to the same workstation number, the same status version number, and the same action type locked. In the locked state, it is not allowed to submit the same action again based on the original interlock action policy. The condition for releasing the locked state is to form a new workstation status version and re-form the current workstation status snapshot, interlock status record, and interlock action policy based on the new workstation status version.

[0137] When the production line controller writes back, it uses an increment-only method to form records. The old workstation status version, interlock action strategy, and execution feedback record are not overwritten. When the same execution feedback record is read repeatedly and a write-back record has already been formed, only the repeated read trace is added, and a new workstation status version is not generated again. When the fields of the execution feedback record change, a new execution feedback record must be formed first, and then the write-back is performed based on the new execution feedback record.

[0138] After the write-back is completed, the production line controller writes the workstation number, original status version number, new status version number, action type, clamping feedback, workpiece positioning feedback, fixture clamping feedback, robot positioning feedback, robot exit feedback, workstation allowed status for the next cycle, status pending review, prohibition of repeated issuance mark, and write-back time into the workstation status database for the next cycle to read. This step only completes the comparison between the collected feedback and the expected data and the write-back of the workstation status version. It does not change the machine tool operating status, the fixture position, trigger robot actions, or release the emergency stop circuit and the safety door interlock.

[0139] When implemented, the workstation status version can be stored in any traceable record area of ​​the production line controller register, edge controller status table, or industrial database. As long as the workstation allowable status for the next cycle can be formed based on the consistent relationship between the collected feedback and the clamping expectation, the positioning expectation, and the fixture expectation, and if the condition is not met, a pending review status is written and the prohibition of repeated issuance under the same status version is locked, it is considered an equivalent implementation.

[0140] Preferably, in a certain steering knuckle processing line, the write-back comparison time can be set to no more than 200 milliseconds, the station status version write time can be set to no more than 500 milliseconds, the repeated reading interval of the same execution feedback record can be set to 100 milliseconds, the number of consecutive retries can be set to 2, and the retry interval can be set to 200 milliseconds; for example, the action type of the target station A01 is exchange, the status version number is A01-20260630-008, the clamping expectation is that the finished product is temporarily held in the finished product clamping position and the blank clamping position is empty, the expected arrival is that there is a part, the expected fixture is clamped in place, and the execution The feedback log shows that the robot arm is in position, the clamping feedback is that the finished product is being held and the finished product temporary storage clamping position record indicates that the finished product is being held, the blank clamping position record indicates that the blank is being released, the workpiece is in position, the fixture clamping feedback is that the fixture is clamped in position, and the robot arm exit feedback is that it has exited. Then the production line controller generates a new workstation status version and writes A01 into the workstation status allowed for processing in the next cycle. If the fixture clamping feedback is that the clamping is unclear, it is written into the pending review status, and the corresponding prohibition of repeated issuance mark for A01-20260630-008-exchange is kept in the locked state.

[0141] In the operating scenario shown in this embodiment: A target workstation A01 is set on a left steering knuckle processing line for automobiles. A01 is the machine tool fixture position registered in the equipment layout table. The production line is equipped with a 6-axis robot. The end effector of the robot has a finished product temporary storage clamp position and a blank clamp position. The workstation status library is stored in an industrial database with only incremental records.

[0142] After A01 completes the machining of the previous left steering knuckle, the machine tool controller indicates the machining completion position, the fixture release position detection element is valid, the workpiece position detection element and the fixture support surface detection element both indicate that there are parts in A01, the robot arm holds the next left steering knuckle blank in the waiting position, and the emergency stop circuit and the protective door interlock have not been restored later than the previous workstation status version.

[0143] When the production line controller enters the loading and unloading preparation stage at A01, it generates a station status version, writes the station number to A01, writes the part type to the left steering knuckle blank, writes the station occupancy status to "part present", writes the fixture opening / closing status to "released", writes the machine tool processing status to "processing completed", writes the robot arm holding status to "holding blank", writes the abnormal reset mark to "none", and generates a status version number A01-20260630-008.

[0144] Before the robot enters A01, the production line controller reads and locks the current workstation status snapshot. The workpiece in the snapshot is in position, the fixture feedback is released and in position, the machine tool completion feedback is completed, the robot gripping feedback is holding blank, and the previous cycle execution record points to A01 and the status version number is continuous.

[0145] When the production line controller determines the interlock status based on the current workstation status snapshot, since A01 has a part, the fixture is released into place, the machine tool is completed, the robot holds the blank, and the robot end effector registers the finished product temporary storage clamping position and the blank clamping position, the interlock status is written to allow exchange.

[0146] Subsequently, the production line controller generates an interlock action strategy based on the allowed exchange. The strategy is bound to the workstation number A01, the status version number A01-20260630-008, the action type exchange, the clamping expectation is finished product temporary storage clamping position holding finished product and blank clamping position empty clamping, the expected arrival is part present, the fixture expectation is clamping in place, and the prohibition of repeated issuance is marked as A01-20260630-008-exchange.

[0147] After the robot controller reads the interlock action strategy, the robot enters A01 from the waiting position. First, it uses the finished product temporary storage clamp to pick up the finished left steering knuckle on A01. Then, it puts the left steering knuckle blank in the blank clamping position into the bearing surface of A01. After the robot leaves the clamping interference range, the A01 clamp enters the clamping and holding as expected. Then, the robot exits the target station safety zone.

[0148] During the execution confirmation period, the production line controller collects feedback on the robot arm's arrival as "in position," the clamping feedback as "holding the finished product" and the finished product's temporary clamping position record as "the finished product is held," the blank clamping position record as "the blank is released," the workpiece arrival feedback as "a workpiece is present," the fixture clamping feedback as "clamped in position," and the robot arm exit feedback as "exited." The controller then writes the above execution feedback into the workstation status database.

[0149] The production line controller compares the collected feedback with the clamping expectations, positioning expectations, and fixture expectations in the interlock action strategy. After confirming that each feedback meets the corresponding expectation, a new workstation status version is formed with A01-20260630-008 as the preceding version. A01 is written into the workstation's allowed status for processing in the next cycle. If a submission request corresponding to A01-20260630-008 appears again under the same status version number, the production line controller will not reissue the original interlock action strategy, but will only retain the duplicate submission trace.

[0150] All calculations involved in the embodiments are dimensionless numerical calculations, and the preset parameters and thresholds in the calculations are set by those skilled in the art according to the actual situation.

[0151] It should be noted that this invention can be deployed on the device itself to realize embedded applications, or it can run on a PC or other terminal with a user interface, thereby meeting various hardware environments and usage requirements.

[0152] The above embodiments can be implemented, in whole or in part, by software, hardware, firmware, or any other combination thereof. When implemented using software, the above embodiments can be implemented, in whole or in part, as a computer program product. The computer program product includes one or more computer instructions or computer programs. When the computer instructions or computer programs are loaded or executed on a computer, all or part of the processes or functions described in the embodiments of this application are generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, the computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via wireless or wired transmission; wired transmission methods include optical fiber, twisted pair, coaxial cable, etc.; wireless transmission includes infrared, microwave, etc. The computer-readable storage medium can be any available medium that a computer can access or a data storage device such as a server or data center containing one or more sets of available media. The available medium can be a magnetic medium (e.g., floppy disk, hard disk, magnetic tape), an optical medium (e.g., DVD), or a semiconductor medium. A semiconductor medium can be a solid-state drive.

[0153] Those skilled in the art will understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and modules described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0154] In the several embodiments provided in this application, it should be understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of modules is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple modules or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between apparatuses or modules may be electrical, mechanical, or other forms.

[0155] The modules described as separate components may or may not be physically separate. The components shown as modules may or may not be physical modules; they may be located in one place or distributed across multiple network modules. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs.

[0156] In addition, the functional modules in the various embodiments of this application can be integrated into one processing module, or each module can exist physically separately, or two or more modules can be integrated into one module.

[0157] If the aforementioned functions are implemented as software functional modules and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0158] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

[0159] In conclusion, the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for interlocking control of workstations in a robotic arm for loading and unloading automotive parts, characterized in that, include: S1. Establish a workstation status version with a status version number for the target workstation, and record the workstation number, component type, workstation occupancy status, fixture opening / closing status, machine tool processing status, robot gripping status, and abnormal reset flag. S2. Before the robot enters the target station, read the workpiece's position status, fixture feedback, machine tool completion feedback, robot gripping feedback, and the previous cycle execution record, and lock the current station status snapshot. S3. Determine the interlock status based on the current workstation status snapshot. The interlock status includes allowing finished product to be picked up, allowing blank to be placed, prohibiting entry, and pending verification. When registering the finished product temporary storage clamping position and blank clamping position in the equipment layout table, it also includes allowing exchange. S4. Generate interlock action strategy based on interlock status, and bind workstation number, status version number, action type, clamping expectation, arrival expectation, fixture expectation, and prohibit repeated issuance mark; S5. Execute the corresponding action according to the interlock action strategy. The action exchange is based on the finished product temporary storage clamping position and blank clamping position registered in the equipment layout table. Collect robot arm positioning feedback, clamping feedback, workpiece positioning feedback, fixture clamping feedback, and robot arm exit feedback. S6. Based on the collected feedback, write back the workstation status version. If the feedback meets expectations, form the workstation allowable status for the next cycle. If the feedback does not meet expectations, retain the original status version number, write the pending review status, and lock the prohibition of repeated issuance flag corresponding to the status version number. Under the locked status, it is not allowed to submit the same action again based on the original interlock action strategy. When the field content changes, generate a new workstation status version, retain the old version, and re-form the current workstation status snapshot, interlock status record, and interlock action strategy based on the new workstation status version before unlocking.

2. The method for interlocking control of workstations in an automotive parts loading / unloading robot according to claim 1, characterized in that, S1 includes: The production line controller will record the status version of the same target workstation as an incremental record, which is generated by submitting the file once. Generate a status version number using workstation number, submission time, and incrementing sequence number; Organize the filing fields in the following order: source reading, time alignment, switch quantity debouncing, field comparison, missing data completion, and version submission; Workstation number, component type, and abnormal reset mark are not automatically filled in; When a field source is missing, the entry is moved to "pending supplementation"; when a field source conflicts, the entry is moved to "pending verification".

3. The workstation interlock control method for an automotive parts loading / unloading robot according to claim 1, characterized in that, S2 include: The production line controller uses the time period from the moment the robot controller generates the pre-entry read request to the moment the current workstation status snapshot is written as the confirmation period. Read in the following order: workpiece arrival status, fixture feedback, machine tool completion feedback, robot gripping feedback, and previous cycle execution record; The read results will be assigned to the same target workstation and the same status version number. The workpiece's arrival status is not updated based on the previous cycle's execution record; If the status version number cannot be inherited, stop locking the current workstation status snapshot and write the reason to be verified.

4. The workstation interlock control method for an automotive parts loading / unloading robot according to claim 1, characterized in that, S3 include: The production line controller determines the interlock status based on a snapshot of the current workstation status. First check the conditions to be reviewed, then check the conditions prohibiting entry, and then check the conditions for allowing exchange, allowing the removal of finished products, and allowing the placement of blanks. Only one interlock state is written under the same target workstation and the same state version number.

5. The workstation interlock control method for an automotive parts loading / unloading robot according to claim 4, characterized in that, S3 also includes: The current workstation status snapshot references a workstation status version that can be traced back to the previous cycle execution record, and there are no unclosed pick-and-place records for the same target workstation between the two; The previous cycle execution record points to the same target workstation. The workpiece is in position, the fixture feedback is released and in position, the machine tool completion feedback is completed, and the robot gripping feedback is holding the blank. When the equipment layout table registers the finished product temporary storage clamping position and the blank gripping position, the production line controller writes the interlock status to allow exchange.

6. The workstation interlock control method for an automotive parts loading / unloading robot according to claim 1, characterized in that, S4 include: After the production line controller verifies that the interlock status record, the current workstation status snapshot, and the status version number in the workstation status version are all consistent, it forms an interlock action strategy when the interlock status is allowed to pick up finished products, allowed to put in blanks, or allowed to exchange. When the interlock status is "Entry Prohibited" or "Pending Review", the interlock action strategy is not generated. The tag that prohibits duplicate issuance is generated by the workstation number, status version number, and action type.

7. The workstation interlock control method for an automotive parts loading / unloading robot according to claim 1, characterized in that, S5 include: The production line controller uses the time from when it submits the interlock action strategy to the robot controller to when the robot exits and the feedback is written to the workstation status database as the execution confirmation period. Before submission, the system searches the workstation status database for the same "Do Not Duplicate Issuance" flag. If there are actions that have not yet been written into the execution feedback record, the system will not submit again. The robot arm is controlled to perform the corresponding action according to the action type in the interlock action strategy, and the robot arm positioning feedback, clamping feedback, workpiece positioning feedback, fixture clamping feedback, and robot arm exit feedback are written into the execution feedback record.

8. The workstation interlock control method for an automotive parts loading / unloading robot according to claim 1, characterized in that, S6 include: The production line controller verifies that the workstation number, status version number, and prohibition of repeated issuance mark in the execution feedback record and interlock action strategy are consistent, and that the clamping feedback meets the clamping expectation, the workpiece arrival feedback meets the arrival expectation, the fixture clamping feedback meets the fixture expectation, the robot arrival feedback is in place, and the robot exit feedback is exited. When these conditions are met, a new workstation status version is formed and written into the workstation allowable status for the next cycle.

9. The method for interlocking control of workstations in an automotive parts loading / unloading robot according to claim 8, characterized in that, S6 also includes: If the clamping feedback does not meet the clamping expectation, the workpiece positioning feedback does not meet the positioning expectation, the fixture clamping feedback does not meet the fixture expectation, the robot positioning feedback is not in position, the robot exit feedback is not exited, or the execution feedback record is missing, any of the following situations are met: robot positioning feedback, clamping feedback, workpiece positioning feedback, fixture clamping feedback, or robot exit feedback. The production line controller writes a pending review status under the same workstation number and the same status version number, and keeps the "Do Not Repeatedly Issue" flag corresponding to the same workstation number, the same status version number, and the same action type locked.

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