A kind of galvanized steel pipe laser drilling beat linkage control method based on residual processing time prediction

Abstract

The application discloses a kind of based on remaining machining time prediction's automobile galvanized steel pipe laser drilling beat linkage control method, specifically includes: by feeding robot workpiece is placed in positioning fixture, central control system reads processing program and generates processing task queue, laser drilling robot completes laser drilling processing;According to the number of uncompleted slot hole, uncompleted waist hole quantity, hole length and laser scanning speed, establish remaining machining time prediction model;According to the remaining machining time and the preparation time of feeding robot, beat linkage condition is judged, when meeting linkage condition, feeding robot is triggered in advance to catch next workpiece and moves into buffer waiting position, and after current workpiece processing is completed, next workpiece is directly switched.The application establishes remaining machining time prediction model and beat linkage control model, realizes the collaborative operation between feeding robot, laser drilling robot and discharging robot, effectively improves automobile pipe fitting laser drilling production efficiency and equipment utilization.

Description

Technical Field

[0001] This invention relates to the field of intelligent manufacturing technology for automotive parts, specifically to a method for controlling the cycle time of laser drilling of galvanized steel pipes for automobiles based on prediction of remaining processing time. Background Technology

[0002] Automotive exhaust system pipes, cooling system pipes, and fuel delivery pipes typically require the machining of multiple mounting holes, positioning holes, and functional holes during production. With the continuous improvement of automation levels in the automotive industry, robotic laser drilling technology is widely used in automotive pipe manufacturing due to its advantages such as high processing precision, high flexibility, and adaptability to complex curved surface machining.

[0003] Existing laser drilling production lines for automotive pipe components typically include a loading robot, a laser processing robot, an unloading robot, positioning fixtures, and a control system. During production, the loading, processing, and unloading processes mostly operate using a fixed-cycle control method. Specifically, while the laser robot is performing the current workpiece processing task, the loading robot is in a waiting state; only after the current workpiece is processed can the loading robot begin to pick up the next workpiece; and only after unloading is completed can the next round of processing begin.

[0004] The above method has the following problems: the feeding time cannot overlap with the processing time, the equipment waiting time is long, the robot utilization rate is low, the production cycle is unstable, and the overall production efficiency is limited.

[0005] Furthermore, different automotive tubular components typically contain varying numbers and types of holes, such as slots, slotted holes, round holes, and irregularly shaped holes. Different hole types correspond to different machining lengths and machining times. Existing control systems usually estimate machining times using fixed empirical values, which makes it difficult to accurately reflect the real-time machining status of the workpiece, thus hindering the implementation of multi-robot collaborative control.

[0006] Therefore, it is necessary to provide a laser drilling control method for automotive pipe parts that can predict the remaining processing time in real time based on the current processing status and dynamically trigger the pre-loading action based on the prediction results, so as to improve equipment utilization and production efficiency. Summary of the Invention

[0007] The purpose of this invention is to provide a cycle time linkage control method for laser drilling of galvanized steel pipes for automobiles based on the prediction of remaining processing time. By establishing a remaining processing time prediction model and a cycle time linkage control model, the method enables the coordinated operation of the loading robot, the laser drilling robot, and the unloading robot.

[0008] To achieve the above objectives, the present invention adopts the following technical solution: a method for laser drilling cycle linkage control of automotive galvanized steel pipes based on remaining processing time prediction, comprising the following steps:

[0009] Step S1: The loading robot places the galvanized steel pipes for automobiles into the positioning fixture;

[0010] Step S2: The central control system reads the machining program for the corresponding model and generates a machining task queue;

[0011] Step S3: The laser drilling robot moves sequentially to each target hole position according to the preset trajectory to perform laser drilling processing;

[0012] Step S4: The central control system establishes a prediction model for the remaining processing time based on the number of unfinished slots, the number of unfinished waist holes, the length of the slots, the length of the waist holes, the laser scanning speed, and the remaining movement time of the robot, and calculates the remaining processing time of the current workpiece.

[0013] Step S5: The central control system acquires the preparation time of the feeding robot and performs cycle time linkage condition determination.

[0014] Step S6: When the preset linkage conditions are met, the loading robot grabs the next workpiece to be processed in advance and moves to the preset hovering waiting position to maintain the grabbing state.

[0015] Step S7: After the current workpiece is processed, the unloading robot will transport the processed workpiece to the finished product area;

[0016] Step S8: The loading robot places the workpiece to be processed into the positioning fixture and starts the next processing cycle.

[0017] A cycle time linkage control system for laser drilling of galvanized steel pipes for automobiles based on prediction of remaining processing time. This system is used to implement the aforementioned cycle time linkage control method for laser drilling of galvanized steel pipes for automobiles based on prediction of remaining processing time, specifically including:

[0018] The loading robot is used to grab galvanized steel pipes for automobiles and place them in positioning fixtures, and to grab the next workpiece to be processed in advance and move it to a preset hovering waiting position after receiving a pre-loading instruction;

[0019] A laser drilling robot is used to move sequentially to each target hole according to a preset trajectory to perform laser drilling on the galvanized steel pipe of the automobile.

[0020] The unloading robot is used to transport the processed workpieces to the finished product area;

[0021] A positioning clamp is used to fix the galvanized steel pipe used in the automobile;

[0022] The central control system is communicatively connected to the loading robot, the laser drilling robot, and the unloading robot, respectively.

[0023] The central control system is used to read the processing program to generate a processing task queue, establish a remaining processing time prediction model based on the number of unfinished slots, the number of unfinished waist holes, the length of the slots, the length of the waist holes, the laser scanning speed, and the remaining movement time of the robot to calculate the remaining processing time of the current workpiece, obtain the preparation time of the loading robot and execute the cycle linkage judgment, and send a pre-loading instruction to the loading robot when the linkage condition is met.

[0024] Compared with the prior art, the significant advantages of this invention are:

[0025] (1) Improve robot utilization: This invention enables the loading robot to perform the next workpiece grabbing preparation action in advance during the current workpiece processing through the remaining processing time prediction model and cycle linkage judgment mechanism, thus hiding the loading time within the processing cycle, thereby realizing the parallel work of the loading robot and the laser drilling robot, and significantly improving the robot utilization.

[0026] (2) Reduce equipment idle time: The present invention uses a pre-loading mechanism to prepare the next workpiece for grabbing and handling before the current workpiece is finished. After the processing is completed, the material change action can be performed immediately, which effectively reduces the waiting time of the laser robot, the waiting time of the loading robot and the waiting time of the unloading robot, and reduces the equipment idle rate.

[0027] (3) Propose a robot hovering and caching mechanism: This invention uses a robot hovering and waiting method to achieve workpiece caching. Compared with the traditional solution of setting up an independent caching station, it does not require an additional caching mechanism, does not require an additional floor area, and does not require an additional clamping device, which reduces equipment investment costs and system complexity, while improving workpiece switching efficiency.

[0028] (4) Achieving three-robot collaborative control: This invention establishes a linkage control mechanism between the loading robot, the laser drilling robot and the unloading robot through a central control system, realizing continuous automatic operation of loading, processing, unloading and the next cycle, and improving the automation level of the entire line;

[0029] (5) Improve production cycle stability: The present invention adopts dynamic prediction and real-time linkage control, which can automatically adjust the pre-feeding timing according to the actual processing progress, avoid cycle imbalance caused by changes in the number of holes, fluctuations in processing time, and changes in robot movement time, and improve the stability of production line operation;

[0030] (6) Improved production efficiency: After adopting the method of the present invention, taking the outer diameter of the galvanized steel pipe for automobiles as Φ41mm and the single product including 2 slots and 5 waist holes as an example, the loading time is about 12 seconds, the unloading time is about 10 seconds, and the processing time of a single piece is about 60 seconds; the cycle time of the entire production line under the traditional control method is about 82 seconds, and after adopting the present invention, the cycle time of the entire production line is reduced to 60 seconds, and the production cycle time optimization rate is improved by about 26.8%;

[0031] (7) Wide range of applications: This invention is not only applicable to laser drilling of galvanized steel pipes for automotive exhaust systems, but also applicable to the production of tubular parts that require laser drilling, such as automotive cooling system pipes, fuel delivery pipes, hydraulic pipeline components, and engineering machinery pipes. It has good promotion and application value. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the automated production system for laser drilling of automotive pipe parts according to the present invention.

[0033] Figure 2 This is a flowchart of the laser drilling control method for automotive pipe parts according to the present invention.

[0034] Figure 3 This is a flowchart of the beat-linkage control logic of the present invention.

[0035] Figure 4 This is a schematic diagram of the remaining processing time prediction model of the present invention.

[0036] Figure 5 This is a schematic diagram of the processing cycle state transition of the present invention.

[0037] Figure 6 This is a schematic diagram of the beat-linkage control framework of the present invention.

[0038] Figure 7 This is a schematic diagram of the modeling framework of the present invention. Detailed Implementation

[0039] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the following embodiments are for illustrative purposes only and are not intended to limit the scope of protection of the present invention. Various modifications and substitutions can be made to the present invention by those skilled in the art without departing from the inventive concept, and all such modifications and substitutions should fall within the scope of protection defined by the claims of the present invention.

[0040] Combination Figures 1-6 The present invention discloses a method for controlling the cycle time of laser drilling of galvanized steel pipes for automobiles based on prediction of remaining processing time, comprising the following steps:

[0041] Step S1: The loading robot places the galvanized steel pipes for automobiles into the positioning fixture;

[0042] Step S2: The central control system reads the machining program for the corresponding model and generates a machining task queue;

[0043] Step S3: The laser drilling robot moves sequentially to each target hole position according to the preset trajectory to perform laser drilling processing;

[0044] Step S4: The central control system establishes a prediction model for the remaining processing time based on the number of unfinished slots, the number of unfinished waist holes, the length of the slots, the length of the waist holes, the laser scanning speed, and the remaining movement time of the robot, and calculates the remaining processing time of the current workpiece.

[0045] Step S5: The central control system acquires the preparation time of the feeding robot and performs cycle time linkage condition determination.

[0046] Step S6: When the preset linkage conditions are met, the loading robot grabs the next workpiece to be processed in advance and moves to the preset hovering waiting position to maintain the grabbing state.

[0047] Step S7: After the current workpiece is processed, the unloading robot will transport the processed workpiece to the finished product area;

[0048] Step S8: The loading robot places the workpiece to be processed into the positioning fixture and starts the next processing cycle.

[0049] Furthermore, in step S4, the process of establishing the remaining processing time prediction model is as follows:

[0050] set up The number of unfinished slots, The number of unfinished waist holes, The length of the slot is... The length of the waist hole. This is the slot weighting coefficient. The weighting coefficient for the lumbar region. For laser scanning speed, This represents the robot's remaining motion time.

[0051] The formula for calculating the remaining scan time is:

[0052]

[0053] Remaining processing time Satisfy the following formula:

[0054]

[0055] Remaining motion time for the robot satisfy:

[0056]

[0057] In the formula, This represents the remaining path distance the robot will take from its current position to the end of the processing phase. This represents the robot's average speed.

[0058] Furthermore, in step S5, the formula for determining the rhythm linkage condition is:

[0059]

[0060] in, This refers to the safety margin factor.

[0061] Preparation time for loading materials Based on capture time With transport time Obtained by superposition:

[0062] +

[0063] When the cycle time linkage condition is met, the central control system triggers the pre-feeding action; when the cycle time linkage condition is not met, the system continues to maintain the current processing state.

[0064] As a specific example, step S1, used to automatically transport and position the galvanized steel pipe for automobiles from the hopper to the laser processing station, specifically includes the following steps:

[0065] Step 1: The central control system receives the production start command and sends the material picking task information to the material loading robot; wherein, the material picking task information includes: the workpiece number to be processed; the workpiece model; the material picking position coordinates; and the target placement position coordinates.

[0066] Step 2: After receiving the material handling task, the loading robot moves to the material bin to be processed according to the preset motion trajectory. In one embodiment, the loading robot is a STEP SR20-1700HT industrial robot. The robot control system calls the corresponding teaching program. The robot's end effector gripper moves to the preset gripping position above the galvanized steel pipe to be processed.

[0067] Step 3: The loading robot controls the gripper to perform the clamping action; after the gripper contacts the galvanized steel pipe of the car, it forms a stable grip; and the gripping is confirmed to be successful by the gripping status detection signal; if the detection result is abnormal, an alarm signal is sent to the central control system and the gripping action is re-executed.

[0068] Step 4: After the loading robot completes the gripping, it lifts the galvanized steel pipe of the car to a safe height; to avoid interference between the robot and the hopper, clamps or other equipment during the handling process; the central control system monitors the robot's current position and operating status in real time.

[0069] Step 5: The loading robot transports the galvanized steel pipes from the car to the laser processing station according to the preset transport trajectory. During the transport process, the robot control system executes path planning according to the taught trajectory to ensure that the workpiece posture remains stable and to reduce positional deviations caused by workpiece shaking.

[0070] Step 6: After the loading robot reaches the preset placement position above the positioning fixture, it slowly descends according to the taught coordinates; the galvanized steel pipe for automobiles is placed on the support surface of the positioning fixture; in one embodiment: the positioning fixture includes: a fixture base plate; an axial positioning block; a radial support block; and a cylinder clamping mechanism; the axial positioning block is used to determine the axial position of the workpiece; the radial support block is used to determine the radial position of the workpiece.

[0071] Step 7: After receiving the workpiece arrival signal, the positioning fixture controls the cylinder clamping mechanism to perform the clamping action; the cylinder pushes the clamping block to move towards the automotive galvanized steel pipe; thus completing the workpiece fixing; wherein: the outer diameter of the automotive galvanized steel pipe is The workpiece is made of galvanized steel; the workpiece is positioned by a fixture and clamped by a cylinder to ensure that it does not shift during processing.

[0072] Step 8: After the fixture clamps, a clamping completion signal is sent to the central control system; the central control system confirms that the workpiece is in a machineable state; then it allows entry into step S2, that is, reading the corresponding machining program and generating a hole machining task. In one embodiment: due to the use of a fixed fixture positioning method, there is no need to configure a vision recognition system; the loading robot can complete the workpiece positioning only through taught coordinates, reducing system costs and improving system stability. In one embodiment: the time required for the loading robot to complete one gripping, handling and placement action is approximately 12 seconds; this time parameter is an important component of the loading preparation time Tl in the subsequent cycle linkage control model.

[0073] As a specific example, step S2 is used to automatically load the corresponding laser drilling program according to the current automotive galvanized steel pipe model, and establish a subsequent processing task queue to provide a control basis for the laser robot to perform drilling processing. The specific steps are as follows:

[0074] Step 1: The central control system receives the clamping completion signal from the positioning fixture. Once the central control system confirms that the workpiece is in place, the fixture is clamped, and the processing station is idle, it initiates the processing task preparation process. In one embodiment, the central control system uses a Siemens PLC control system. The PLC, as the main control unit of the production line, is responsible for: coordinating the loading robot; coordinating the laser robot; coordinating the unloading robot; cycle time linkage control; and processing data management.

[0075] Step 2: The central control system reads the current production order information; obtains: product model; product batch; processing program number; process parameter number. Then, it automatically matches the corresponding processing program based on the product model. For example, for Φ41mm automotive galvanized steel pipe products, it calls the corresponding hole machining database.

[0076] Step 3: The central control system reads the hole position information corresponding to this model of automotive pipe fitting; the hole position information includes: hole position number; hole position coordinates; hole position type; processing sequence; laser parameters. In one embodiment: each workpiece contains: 2 slots; 5 waist holes. This corresponds to 7 processing task nodes.

[0077] Step 4: The central control system establishes a hole type attribute table based on the hole position type; where: slotted holes are defined as the first hole type;

[0078] The waist hole is defined as the second hole type. Record the following: slot length: =12.2mm waist hole length: =6.5mm is used for subsequent calculations to predict the remaining processing time.

[0079] Step 5: The central control system generates a processing task queue based on the hole position coordinate information; for example: Task 1: Slot 1; Task 2: Slot 2; Task 3: Waist Hole 1; Task 4: Waist Hole 2; Task 5: Waist Hole 3; Task 6: Waist Hole 4; Task 7: Waist Hole 5. Simultaneously, it records: the current task number; the number of completed tasks; and the number of incomplete tasks. This is used for real-time processing status tracking.

[0080] Step 6: The central control system automatically generates the robot's motion trajectory based on the hole distribution; specifically, this includes: First sub-step: acquiring the three-dimensional coordinates of all holes; Second sub-step: calculating the distance between adjacent holes; Third sub-step: establishing a set of motion paths; Fourth sub-step: generating a sequence of robot trajectory points; Fifth sub-step: generating processing posture parameters; Sixth sub-step: generating trajectory switching points; Seventh sub-step: generating avoidance action paths; Eighth sub-step: completing trajectory planning. In one embodiment: the trajectory planning result is sent to the FANUC M-20iB robot controller.

[0081] Step 7: The central control system sends processing parameters to the laser; these parameters include: laser power; laser on-time; laser off-time; scanning speed; and processing mode. In one embodiment: the laser used is a Jiaqiang BT220 1500W laser. The laser scanning speed is set as follows: =40mm / s. Maintain a constant output speed during processing.

[0082] Step 8: The central control system completes the initialization of the machining task; establishes the current workpiece machining status variables, including: current workpiece number; total number of holes; number of holes completed; number of holes remaining; current machining hole position; number of remaining slots. Number of remaining waist holes Simultaneously, a remaining processing time prediction buffer is established; this is used for real-time calculation of the remaining processing time in subsequent step S4. After initialization, the central control system sends a processing start command to the laser drilling robot; proceeding to step S3.

[0083] Step S2 achieves the following: automatic identification of workpiece processing tasks; automatic reading of hole position database; automatic establishment of processing task queue; automatic generation of robot trajectory; automatic configuration of laser processing parameters; automatic establishment of basic data for remaining time prediction; providing data support for subsequent cycle time linkage control; and improving the automation level and processing stability of laser drilling of automotive galvanized steel pipes.

[0084] As a specific example, S3 controls the laser drilling robot to sequentially complete the laser processing of each hole on the galvanized steel pipe of the automobile according to the processing task queue, and updates the processing status information in real time to provide a data basis for predicting the remaining processing time. In one embodiment: the laser drilling robot is a FANUC M-20iB six-axis industrial robot; the laser is a Jiaqiang BT220 1500W laser; the processing object is... Galvanized steel pipes for automobiles; each workpiece includes: 2 slots; 5 waist holes. Specific steps are as follows:

[0085] Step 1: The laser drilling robot receives the processing start command from the central control system; the robot controller reads the processing task queue; obtains: current workpiece number; hole number; hole coordinates; hole type; laser processing parameters; and completes processing task initialization. The robot then moves from the safe waiting position to the processing start point of the first hole.

[0086] Step 2: The robot moves to the target hole according to the preset trajectory. During the movement, the robot controller performs real-time coordinate transformation, attitude adjustment, path interpolation, and speed planning to ensure that the laser processing head remains perpendicular to the workpiece surface or at a preset angle. In one embodiment, the robot's motion trajectory is established using a combination of offline teaching and on-site calibration. Since the workpiece is positioned using a fixed fixture, no vision camera is required for positioning.

[0087] Step 3: After the robot reaches the hole processing position, the central control system sends a laser start command to the laser; the laser outputs a laser beam; the laser beam is focused by the laser processing head and acts on the surface of the galvanized steel pipe of the automobile, forming the initial perforation point. At the same time, the system records the hole processing start time as a basis for subsequent processing time statistics.

[0088] Step 4: Perform the corresponding processing action according to the hole type; when the hole type is a slot: the robot performs laser cutting according to the slot contour trajectory;

[0089] The length of the slot is: =12.2mm;

[0090] Corresponding theoretical scan time:

[0091]

[0092] in: ;

[0093] but:

[0094]

[0095] After completing the slot contour cutting, turn off the laser.

[0096] Step 5: When the hole type is a waist hole: the robot performs laser cutting according to the contour trajectory of the waist hole;

[0097] The length of the waist hole is:

[0098]

[0099] Corresponding theoretical scan time:

[0100]

[0101] Right now:

[0102]

[0103] After completing the waist hole contour cutting, turn off the laser.

[0104] In one embodiment: the following tasks are completed sequentially according to the processing task queue: slot 1; slot 2; waist hole 1; waist hole 2; waist hole 3; waist hole 4; waist hole 5. A total of 7 hole processing tasks are performed.

[0105] Step 6: After each hole is machined, the central control system updates the machining status database in real time; including:

[0106] Number of completed holes; Number of remaining holes; Number of holes currently being machined, and number of remaining slots. Number of remaining waist holes Simultaneously, the following data is recorded: single-hole processing time; robot travel time; laser start-up and stop time. This data is written to the processing buffer in real time.

[0107] Step 7: After completing the current hole, the robot automatically moves to the next hole. The system executes the following process: First sub-step: Obtain the coordinates of the next hole; Second sub-step: Calculate the distance between the current position and the target position; Third sub-step: Generate the movement trajectory; Fourth sub-step: Execute the robot's movement; Fifth sub-step: Reach the target position; Sixth sub-step: Adjust the processing posture; Seventh sub-step: Confirm that the processing conditions are met; Eighth sub-step: Start processing the next hole. The above process is repeated until all holes are processed.

[0108] Step 8: Once all holes in the processing task queue are completed, the central control system confirms: and: At this point, the current workpiece processing is determined to be complete; subsequently, the following steps are executed: First sub-step: Turn off laser output; Second sub-step: Save processing record; Third sub-step: Update workpiece status; Fourth sub-step: Send processing completion signal to PLC; Fifth sub-step: Robot returns to safe waiting position; Sixth sub-step: Wait for unloading robot to enter the workstation; Seventh sub-step: Allow fixture to perform release action; Eighth sub-step: Proceed to step S4 for remaining processing time statistics and cycle time linkage control. Through step S3, the entire process of laser drilling of automotive galvanized steel pipes is automatically controlled; the FANUC M-20iB robot completes the hole trajectory movement; the Jiaqiang BT220 laser completes the hole cutting; processing status information is recorded in real time; and the number of remaining slots is dynamically updated. and the number of remaining waist holes This provides a real-time data foundation for the remaining processing time prediction model in step S4, thereby enabling subsequent cycle time linkage control and pre-feeding triggering functions.

[0109] As a specific example, step S4 is used to dynamically predict the remaining processing time of the current workpiece based on the current real-time processing status of the workpiece, the remaining hole information, and the remaining motion path information of the robot, and uses the prediction result as the basis for cycle time linkage control. In one embodiment: the central control system adopts a Siemens PLC control system; the remaining processing time is calculated using a real-time dynamic update method; the refresh cycle is preferably 100ms to 500ms. Specifically, it includes the following steps:

[0110] Step 1: Obtain the current workpiece processing status information; the central control system reads the processing status buffer data in real time.

[0111] Obtain: current workpiece number; current machined hole number; number of completed holes; number of remaining holes; current robot coordinates; current machining progress. Simultaneously confirm whether the current machining task is in normal operation. If any of the following are detected: emergency stop; alarm; laser malfunction, then pause the remaining time prediction calculation.

[0112] Step 2: Count the number of remaining slots The central control system traverses the processing task queue; identifies unfinished slotting tasks; and counts the remaining slots. The calculation formula is:

[0113]

[0114] in: This represents the total number of slots; This represents the number of slots that have been completed.

[0115] In one embodiment: Total number of slots: For example: when one slot has been completed:

[0116] Step 3: Count the remaining number of waist holes The central control system continues to traverse the task queue; identifies unfinished waist hole tasks; and counts the remaining waist hole tasks. Calculation formula:

[0117]

[0118] in: This represents the total number of lumbar perforations. This represents the number of waist holes that have been completed.

[0119] In one embodiment: Total number of waist holes: For example: when 3 waist holes have been completed:

[0120] Step 4: Calculate the remaining laser scanning time The central control system calculates the remaining laser processing time based on the remaining hole position information. Considering the different processing times for different hole types, a hole type weighting coefficient is introduced. Specifically: slot weighting:

[0121]

[0122] Waist hole weight:

[0123]

[0124] The formula for calculating the remaining scan time is:

[0125]

[0126] in: The length of the slot; The length of the waist hole; The laser scanning speed is used to calculate the theoretical processing time for the remaining holes.

[0127] Step 5: Obtain the robot's remaining motion path; the central control system reads the robot's current position; and according to the input...

[0128] The task queue retrieves the coordinates of the remaining holes. Then, the following sub-steps are executed: First sub-step: Obtain the current robot position; Second sub-step: Obtain the next target hole; Third sub-step: Obtain the coordinates of all subsequent holes; Fourth sub-step: Establish the set of remaining paths; Fifth sub-step: Calculate the distance between adjacent holes; Sixth sub-step: Generate the remaining trajectory sequence; Seventh sub-step: Accumulate the length of all remaining paths; Eighth sub-step: Obtain the total remaining motion distance. Let:

[0129]

[0130] For the first The remaining path distance of the segment.

[0131] Step 6: Calculate the robot's remaining motion time The central control system calculates the robot's remaining motion time based on the remaining path length. The calculation formula is as follows:

[0132]

[0133] in: For the remaining trajectory, the first Segment path length; This represents the robot's average speed. In one embodiment: Historical statistical averages or real-time sampled values ​​can be used. The calculation results reflect the time required for the robot to complete the remaining motion.

[0134] Step 7: Generate the total remaining processing time The central control system adds the remaining scanning time to the remaining motion time to obtain the total remaining processing time for the current workpiece. The calculation formula is as follows:

[0135] +

[0136] Right now:

[0137]

[0138] in: This indicates the remaining processing time for the current workpiece. After generating the result, it is written to the real-time data area of ​​the central control system and simultaneously sent to the cycle time linkage control module.

[0139] Step 8: Dynamically correct the prediction results. To improve prediction accuracy, the central control system establishes a processing time database. The database records: actual processing time; actual robot movement time; actual cycle time; product model information. Let: For predicting time; For actual time. Prediction error is defined as:

[0140]

[0141] when: At that time, the central control system automatically corrects: and Parameters. These parameters allow the predicted results to gradually approximate the actual processing time. After continuous production operation, the prediction error can be controlled within: Within.

[0142] Step S4 establishes a prediction model for remaining processing time based on: the number of remaining slots, the number of remaining waist holes, hole length, hole weight, and the remaining robot motion path. Compared to traditional methods of estimating based on fixed empirical values, this model can reflect the current workpiece processing progress in real time; accurately predict the remaining processing time of the current workpiece; and provide a reliable basis for the cycle time determination in step S5. This enables the loading robot to intervene earlier, reduces equipment waiting time, and improves overall production efficiency.

[0143] As a specific example, step S5 is used to dynamically decide whether the loading robot should perform the pre-loading action in advance based on the remaining processing time calculated in step S4, thereby realizing the cycle linkage control between the loading robot, the laser drilling robot, and the unloading robot. In one embodiment: the central control system adopts a Siemens PLC control system; the linkage determination cycle is preferably 100ms to 500ms; it is executed cyclically throughout the entire processing process. Specifically, it includes the following steps:

[0144] Step 1: Obtain the current remaining processing time The central control system receives the remaining processing time data output in step S4; it reads the data in real time. ,in: This indicates the time required for the current workpiece to complete machining of all remaining holes. This time includes: remaining laser scanning time; remaining robot movement time. The central control system uses this as a basic parameter for cycle time linkage control.

[0145] Step 2: Obtain the current status of the loading robot. The central control system reads the robot's operating status and determines whether the robot is in: idle state; task execution state; fault state; pre-loading state; or hovering waiting state. If the robot is in a fault state, the cycle linkage control is paused. If the robot is in an idle state, the linkage determination is allowed to continue.

[0146] Step 3: Calculate the material loading and gripping time The central control system reads the time required for the loading robot to grasp the workpiece. This includes: First sub-step: Robot moves to the hopper; Second sub-step: Gripper positioning; Third sub-step: Gripper closing; Fourth sub-step: Grasp confirmation; Fifth sub-step: Workpiece lifting; Sixth sub-step: Workpiece removal from the hopper; Seventh sub-step: Attitude adjustment; Eighth sub-step: Entering transport state. The above time is defined as: In one embodiment:

[0147] Step 4: Calculate the loading and handling time The central control system calculates the time required for the loading robot to move the workpiece from the hopper to the hovering waiting position. This includes: robot acceleration time; constant speed movement time; deceleration time; and attitude adjustment time. Defined as: In one embodiment:

[0148]

[0149] Step 5: Generate material preparation time The central control system adds the grabbing time and the handling time together to obtain the material preparation time.

[0150] +

[0151] Substitute the data:

[0152]

[0153]

[0154] This parameter represents the time required from receiving the pre-loading instruction to the robot completing the grasp and reaching the hovering waiting position.

[0155] Step 6: Execute cycle time linkage determination, and the central control system reads the safety margin coefficient. In one embodiment: The linkage judgment algorithm is then executed: when the judgment condition is met, it means that the remaining processing time of the current workpiece is less than or equal to the preparation time of the loading robot; if the loading action is started immediately at this time, the robot can complete the preparation of the next workpiece before the current workpiece is finished.

[0156] Step 7: Generate the linkage control result, when:

[0157]

[0158] Result generated: Continue processing, maintain the current state.

[0159] when:

[0160]

[0161] Result generated: Pre-loading is allowed, and a trigger signal is sent to the PLC linkage module. Simultaneously, the linkage status of the workpiece is locked.

[0162] Avoid repeatedly triggering the pre-feeding action.

[0163] Step 8: Sending a pre-loading command. Once the linkage conditions are met, the central control system sends a pre-loading command to the loading robot. The command includes: workpiece number; pick-up coordinates; hovering waiting coordinates; and transport trajectory number. Upon receiving the command, the loading robot immediately executes the next workpiece grabbing action and proceeds to step S6. Simultaneously, the laser drilling robot continues processing the current workpiece; the unloading robot remains in standby mode, forming a three-robot parallel collaborative working mode.

[0164] Step S5 establishes a cycle-linked control mechanism, dynamically determining the optimal pre-feeding timing based on the remaining processing time prediction results. Compared to the traditional serial control method—processing ends, feeding begins, and the next cycle starts—this invention adopts:

[0165] The parallel control method involves predicting the remaining time during processing, feeding materials in advance, pausing and waiting, and immediately changing materials upon completion of processing.

[0166] This achieves the following: advance preparation of the next workpiece; reduced robot waiting time; improved equipment utilization; shortened workpiece changeover time; coordinated operation of three robots; reduced production cycle time from 82 seconds to 60 seconds; and increased overall production efficiency by 26.8%.

[0167] As a specific example, step S6 is used to complete the grabbing and handling of the next workpiece to be processed in advance after the cycle linkage condition is met, and to achieve workpiece buffering by robot hovering and waiting, thereby shortening the workpiece switching time and improving equipment utilization.

[0168] Unlike traditional automated production lines that use independent buffer stations, this invention utilizes the loading robot itself as a buffer carrier. During processing, it pre-grabs the next workpiece and holds it in a hovering, waiting state, eliminating the need for additional buffer mechanisms and floor space. Specifically, it includes the following steps:

[0169] Step 1: Receiving the Pre-Loading Instruction. When the linkage judgment condition in step S5 is met, the central control system sends a pre-loading instruction to the loading robot. The pre-loading instruction includes: the workpiece number to be grasped; the coordinates of the hopper; the grasping posture parameters; the hovering waiting coordinates; and the motion trajectory number. After receiving the pre-loading instruction, the loading robot immediately enters the pre-loading working mode. At the same time, the central control system records the pre-loading start time as a basis for subsequent cycle count statistics.

[0170] Step 2: Grab the next automotive pipe component to be processed. The loading robot moves to the processing hopper according to a preset trajectory. Then, the following actions are performed: First sub-step: The robot moves to the gripping preparation position; Second sub-step: The end effector gripper opens; Third sub-step: The robot descends to the gripping height; Fourth sub-step: The gripper closes to hold the workpiece; Fifth sub-step: The gripping status is checked; Sixth sub-step: Grabbing is confirmed successful. If the gripping detection fails, the gripping process is repeated; after a preset number of consecutive failures, an abnormal alarm signal is sent to the central control system. In one embodiment, the gripping object is: Φ41mm galvanized automotive steel pipe.

[0171] Step 3: After successfully grabbing the workpiece, the loading robot lifts it to a safe height and moves it to the hovering waiting position.

[0172] The robot then moves to a hovering position according to a preset trajectory. This hovering position is located outside the safe area above the positioning fixture and avoids the following areas: the laser robot's movement area; the unloading robot's movement area; and the laser processing area. The central control system monitors the robot's position, workpiece status, and safe area status in real time, ensuring that no motion interference occurs during the operation of each robot.

[0173] Step 4: Maintain hovering and waiting state. Once the robot reaches the hovering and waiting position, it maintains its current posture and continues to hold the workpiece. It enters the hovering buffer state. At this time: the workpiece has been gripped; the workpiece has been transported; the workpiece is ready for loading; but it will not immediately enter the processing station. The central control system continuously monitors: processing completion signal, fixture status signal, unloading completion signal, and whether the waiting workpiece switching conditions are met. In one embodiment, during the robot's hovering and waiting period, the laser drilling robot continues to process the remaining holes on the current workpiece. Therefore, the processing of the current workpiece and the preparation of the next workpiece are executed synchronously.

[0174] Step 5: Receive the material changeover execution command. When the following conditions are met: the current workpiece has been processed, the fixture has been released, and the unloading robot has completed unloading, the central control system generates a material changeover execution command. This command is sent to the loading robot. After receiving the command, the loading robot exits the hovering waiting state and simultaneously starts the workpiece switching program. Since the workpiece has already been gripped and transported in advance, there is no need to return to the hopper to retrieve it, significantly shortening the material changeover time.

[0175] Step 6: After pre-loading is completed and the robot prepares to enter the next cycle, it moves to the positioning fixture according to the preset trajectory. The following actions are performed: First sub-step: Adjust the placement posture; Second sub-step: Lower to the placement position; Third sub-step: Release the workpiece; Fourth sub-step: The fixture uses a cylinder to clamp the workpiece; Fifth sub-step: Confirm clamping completion; Sixth sub-step: Send a loading completion signal to the central control system. Subsequently: The central control system starts the next workpiece processing program. Proceed to step S8.

[0176] By establishing a robot hovering buffer mechanism in step S6, the following can be achieved: during the processing stage, the next workpiece is grabbed in advance, the robot hovers and waits, and the material is changed immediately after processing is completed. Compared with the traditional method of the robot returning to the material bin for material retrieval, handling, and loading after processing, this invention has the following advantages: eliminating independent buffer stations; reducing equipment footprint; reducing robot idle travel; improving robot utilization; shortening workpiece changeover time; improving production cycle stability; realizing three-robot collaborative control; and providing key technical support for reducing the production cycle from 82 seconds to 60 seconds.

[0177] As a specific example, step S7 is used to remove the processed workpiece from the positioning fixture and transport it to the finished product area after all laser drilling processing of the current automotive galvanized steel pipe has been completed, creating conditions for the next workpiece to enter the processing station, thereby realizing continuous automated production. In one embodiment: the unloading robot adopts a STEP SR20-1700HT industrial robot; it shares a central control system with the loading robot for cycle time coordinated control. Specifically, it includes the following steps:

[0178] Step 1: Receive processing completion signal. After the laser drilling robot completes processing all holes, the central control system receives the processing completion signal. Simultaneously, it confirms: Current workpiece status = Processing completed. Remaining number of slots / holes. Number of remaining waist holes The laser status is "Off"; the laser robot status is "Safe Waiting". The central control system generates a material unloading task and sends an unloading command to the unloading robot. The unloading command includes: workpiece number; workpiece position coordinates; gripping posture parameters; target coordinates of the finished product area; and unloading trajectory number.

[0179] Step 2: The positioning fixture releases, and the central control system sends an unlock command to the fixture. The fixture cylinder then retracts, releasing the clamp on the galvanized steel pipe. Specifically, this includes: First sub-step: Closing the clamping holding signal;

[0180] The second sub-step: cylinder retraction; the third sub-step: clamping block retraction; the fourth sub-step: workpiece release from constraint; the fifth sub-step: detecting the fixture's open position; the sixth sub-step: sending a fixture release completion signal to the PLC. The system only allows the unloading robot to enter the workstation after the fixture is fully open.

[0181] Step 3: The unloading robot grips the processed workpiece. After receiving the clamp release signal, the unloading robot moves to the workpiece gripping position according to the preset trajectory. Specifically, this includes: First sub-step: moving to the gripping preparation position; Second sub-step: adjusting the gripping posture; Third sub-step: opening the grippers; Fourth sub-step: descending to the gripping height; Fifth sub-step: closing the grippers to hold the workpiece; Sixth sub-step: checking the gripping status. Once successfully gripped, the robot raises the workpiece to a safe height. In one embodiment, the workpiece is a Φ41mm galvanized steel pipe for automobiles with two slots and five waist holes machined.

[0182] Step 4: Transfer to the finished product area. After the unloading robot picks up the workpiece, it moves towards the finished product area along a preset trajectory. During the transfer process: the central control system monitors in real time the robot coordinates, workpiece status, and interference area status to ensure no motion interference with the laser drilling robot and the loading robot. Simultaneously, the PLC continuously executes safety interlock judgments. When an abnormality is detected, a deceleration or stop command is immediately triggered.

[0183] Step 5: Release the workpiece and update production data. After the unloading robot reaches the finished product area, it performs the unloading action. This includes: First sub-step: Descending to the unloading position; Second sub-step: Opening the grippers; Third sub-step: Release the workpiece; Fourth sub-step: Confirming the workpiece is detached from the grippers; Fifth sub-step: The robot returns to a safe height; Sixth sub-step: Sending an unloading completion signal to the central control system. Simultaneously, the central control system updates the production database. Recorded information includes: workpiece number, product model, processing start time, processing end time, processing cycle, equipment operating status, and production batch information, used for subsequent production statistics and cycle time analysis.

[0184] Step 6: Generate a workpiece switching permission signal. After receiving the unloading completion signal, the central control system performs a workpiece switching determination. When the following conditions are met: unloading complete, fixture in open state, loading robot in hovering waiting state, and next workpiece ready, a loading permission signal is generated and sent to the loading robot. At this time, the loading robot immediately exits the hovering waiting state and executes the next workpiece loading action. This achieves: current workpiece unloading completed; next workpiece immediately loaded; entering the next processing cycle, thus forming a continuous automated production process.

[0185] Step S7 achieves automatic workpiece unloading and automatic production data recording upon completion of processing. This works in synergy with the pre-loading mechanism in step S6. Compared to the traditional method of: processing completed; unloading; returning to the hopper for material retrieval; reloading, this invention adopts: processing completed; unloading; immediately switching to the next workpiece; continuing processing. This results in: reduced station idle time; increased robot utilization; continuous automated production; improved equipment operational stability; shortened workpiece changeover time; stable production cycle; and coordinated control of the loading robot, laser drilling robot, and unloading robot, providing crucial support for a 26.8% increase in overall production efficiency.

[0186] As a specific example, step S8 is used to start a new round of laser drilling processing for automotive galvanized steel pipes after the current workpiece has been unloaded and the next workpiece has been pre-loaded, thereby forming a continuous cyclic production mode and achieving stable operation of the production line. In one embodiment: step S8 serves as a closed-loop control link for steps S1 to S7. When step S7 is completed, the central control system automatically starts step S8. Specifically, it includes the following steps:

[0187] Step 1: Confirm that the next workpiece has arrived. The central control system receives the loading completion signal sent by the loading robot.

[0188] Simultaneously read the fixture status information. Confirm that the workpiece has been placed, the fixture has been clamped, the positioning is normal, and the robot has exited the workstation. When all the above conditions are met, determine that the next workpiece has entered the waiting-for-processing state. Proceed to the next step.

[0189] Step 2: Initialize the new workpiece machining parameters. The central control system reads the machining program corresponding to the current workpiece. A new machining task data area is established. The initialization content includes: workpiece number, product model, total number of holes, number of completed holes, number of remaining holes, number of slots, number of waist holes, and machining start time. In one embodiment, the initialization parameters are as follows: number of slots = 2, number of waist holes = 5, total number of holes = 7, and simultaneously clear the machining cache data of the previous workpiece.

[0190] Step 3: Rebuild the remaining machining time prediction model. The central control system re-establishes the time prediction parameters based on the current workpiece machining information. Specifically, this includes: First sub-step: Initialize the number of remaining slots. Second sub-step: Initialize the number of remaining waist holes The third sub-step: Initialize the hole shape weight coefficients; the fourth sub-step: Initialize the robot trajectory data; the fifth sub-step: Establish the remaining path model; the sixth sub-step: Establish the remaining processing time prediction model. At this point: , Then, re-enter the time prediction calculation process described in step S4.

[0191] Step 4: Initiate the laser processing task. The central control system sends a processing start command to the laser drilling robot. After receiving the command, the robot executes the following steps: First sub-step: Enter processing preparation state; Second sub-step: Move to the first hole position; Third sub-step: Adjust processing posture; Fourth sub-step: The laser enters standby state; Fifth sub-step: Establish the processing coordinate system; Sixth sub-step: Start processing at the first hole position. This completes the initiation of the new workpiece processing.

[0192] Step 5: Update the production cycle statistics. The central control system writes the production data of the previous workpiece into the production database.

[0193] The recorded information includes: workpiece number, processing cycle, loading time, processing time, unloading time, cycle time, robot running time, and equipment utilization rate. It also generates: shift statistics, daily output statistics, and equipment efficiency statistics for subsequent production management and cycle time optimization analysis.

[0194] Step 6: Enter the next cycle control process. When the new workpiece starts to be processed, the central control system re-enters step S3.

[0195] The process then repeats in a loop as follows: S3 laser processing, S4 remaining time prediction, S5 linkage judgment, S6 pre-loading, S7 unloading, S8 next cycle, return to S3, until the production order is completed, production is manually stopped, or the system malfunctions, at which point the system exits the loop operation mode.

[0196] Step S8 establishes a complete automated cyclic production mechanism, achieving a closed-loop control process of material loading, processing, prediction, linkage, pre-loading, unloading, and the next cycle. Compared to traditional discrete production modes, this invention offers the following advantages: continuous automated production; automatic switching of processing tasks; automatic management of processing data; continuous operation of the remaining time prediction model; continuous operation of cycle time linkage control; reduced manual intervention; improved equipment utilization; improved production cycle time stability; shortened workpiece changeover time; collaborative operation of three robots; reduced single-piece production cycle time from 82 seconds to 60 seconds; and an overall production efficiency increase of approximately 26.8%.

[0197] In one specific embodiment:

[0198] The automotive tubing is made of galvanized steel.

[0199] The outer diameter of the pipe fitting is Φ41mm;

[0200] The positioning fixture adopts a cylinder clamping structure;

[0201] The control system uses Siemens PLC;

[0202] The laser drilling robot uses a FANUC M-20iB six-axis robot;

[0203] The loading robot uses a STEP SR20-1700HT industrial robot;

[0204] The unloading robot uses the STEP SR20-1700HT industrial robot;

[0205] The laser used is a Jiaqiang BT220 1500W laser;

[0206] The automotive fitting includes 2 slots and 5 waist holes;

[0207] The slot length is 12.2mm;

[0208] The waist hole is 6.5mm long;

[0209] The laser scanning speed is 40 mm / s;

[0210] The processing time for a single piece is approximately 60 seconds.

[0211] The feeding time is approximately 12 seconds;

[0212] The feeding time is approximately 10 seconds.

[0213] This invention also provides a laser drilling cycle linkage control system for automotive galvanized steel pipes based on remaining processing time prediction. This system is used to implement the aforementioned laser drilling cycle linkage control method for automotive galvanized steel pipes based on remaining processing time prediction, specifically including:

[0214] The loading robot is used to grab galvanized steel pipes for automobiles and place them in positioning fixtures, and to grab the next workpiece to be processed in advance and move it to a preset hovering waiting position after receiving a pre-loading instruction;

[0215] A laser drilling robot is used to move sequentially to each target hole according to a preset trajectory to perform laser drilling on the galvanized steel pipe of the automobile.

[0216] The unloading robot is used to transport the processed workpieces to the finished product area;

[0217] A positioning clamp is used to fix the galvanized steel pipe used in the automobile;

[0218] The central control system is communicatively connected to the loading robot, the laser drilling robot, and the unloading robot, respectively.

[0219] The central control system is used to read the processing program to generate a processing task queue, establish a remaining processing time prediction model based on the number of unfinished slots, the number of unfinished waist holes, the length of the slots, the length of the waist holes, the laser scanning speed, and the remaining movement time of the robot to calculate the remaining processing time of the current workpiece, obtain the preparation time of the loading robot and execute the cycle linkage judgment, and send a pre-loading instruction to the loading robot when the linkage condition is met.

[0220] Example 1

[0221] I. System Composition

[0222] This embodiment relates to a laser drilling control method for automotive pipe components based on cycle time linkage and processing time prediction.

[0223] Combination Figure 7 The automated processing unit mainly includes: a loading robot 1; a material hopper 2; a positioning fixture 3; a laser drilling robot 4; a laser 5; a laser processing head 6; a unloading robot 7; a finished product area 8; and a central control system 9.

[0224] The buffer has 10 waiting bits. Among them: the loading robot 1 is a STEP SR20-1700HT industrial robot; the unloading robot 7 is a STEP SR20-1700HT industrial robot; the laser drilling robot 4 is a FANUC M-20iB six-axis industrial robot; and the laser 5 is a Jiaqiang BT220 1500W laser.

[0225] The central control system 9 is connected to each robot controller and laser controller via industrial Ethernet to achieve unified scheduling of the production line.

[0226] II. Positioning Fixture Structure

[0227] The positioning fixture 3 is fixedly installed at the center of the machining station. The positioning fixture includes: a fixture base plate; an axial positioning block; a radial support block; a pneumatic clamping mechanism; and a limiting mechanism. After the automotive pipe part is placed in the fixture: the axial positioning block determines its length position; the radial support block determines its radial position; and the pneumatic clamping mechanism completes the clamping and fixing. Because a fixed reference positioning method is used, no vision recognition system is needed to meet the machining positioning requirements. The robot only needs to establish a machining coordinate system through teaching to complete laser drilling.

[0228] III. Processing Objects

[0229] In this embodiment, the automotive pipe is a metal pipe for the exhaust system.

[0230] Each workpiece includes: 2 slots; 5 waist holes. The slot length is: Waist hole length:

[0231] .

[0232] IV. Feeding process

[0233] At the start of production: The loading robot 1 picks up the automotive tubing to be processed from the material hopper 2. The robot completes the following steps according to a preset trajectory: picking up; lifting; transferring; and placing. The workpiece is then placed in the positioning fixture 3. The positioning fixture automatically performs the clamping action. After clamping is complete: the fixture sends a clamping completion signal to the central control system. The central control system then starts the laser processing program. In this embodiment, the loading robot takes approximately 12 seconds to complete one loading cycle. That is: .

[0234] V. Laser Drilling Process

[0235] The central control system reads the corresponding model's processing program and generates a hole-position processing queue. The laser drilling robot 4 drives the laser processing head 6 to move sequentially to the target hole positions according to a preset trajectory. The laser 5 outputs a laser beam to complete the cutting process. In this embodiment: Laser scanning speed: .

[0236] Processing time for a single slot:

[0237] Substitute parameters:

[0238]

[0239] Processing time for a single waist hole:

[0240]

[0241] After all the holes on the workpiece are machined, the laser robot automatically returns to a safe waiting position. In actual production, due to the robot's movement, acceleration and deceleration, and laser start-up and stop times, the total machining time for a single workpiece is approximately 60 seconds.

[0242] VI. Remaining Processing Time Prediction

[0243] During the processing: The central control system monitors in real time: the current hole position being processed; the completed holes; and the remaining holes.

[0244] set up: This represents the number of remaining slots; This represents the number of remaining waist holes; This refers to the slot weighting coefficient; This is the weighting coefficient for the lumbar anastomosis. In this embodiment: ; The remaining scan time is calculated as follows:

[0245]

[0246] The robot's remaining motion time is:

[0247]

[0248] in:

[0249] Indicates the remaining path distance;

[0250] This represents the robot's average speed.

[0251] Therefore, the total remaining processing time is:

[0252] +

[0253] The central control system refreshes once every 100ms. value.

[0254] VII. Beat-linked control

[0255] Central control system obtains: Remaining processing time Material preparation time Simultaneously set: safety margin factor In this embodiment: The system makes judgments based on the following conditions: If the condition is not met: maintain the current state. If the condition is met: immediately trigger the pre-loading action. The central control system sends a pre-loading command to the loading robot. The loading robot begins execution: grab the next workpiece; transport; wait. After completion, it stops at buffer waiting position 10. This will not affect the processing of the current workpiece.

[0256] VIII. Workpiece Switching Process

[0257] After the current workpiece is processed: the central control system sends a feeding command to the unloading robot. The unloading robot then transports the processed workpiece to the finished product area. In this embodiment: the unloading time is 10 seconds. That is: Simultaneously, the loading robot feeds the next workpiece from the buffer waiting position into the positioning fixture. After the fixture completes clamping, the next processing cycle is immediately started. Therefore, the loading action is hidden within the processing cycle.

[0258] Example 2

[0259] This embodiment performs dynamic parameter correction.

[0260] To further improve prediction accuracy, the central control system establishes a processing database. The database records: workpiece type, processing time, loading time, unloading time, and actual cycle time. The system stores data from the most recent 100 processing cycles.

[0261] Let the prediction time be... The actual time is .error satisfy:

[0262]

[0263] when: The system automatically corrects the parameters at that time. and This allows the predicted results to gradually approximate the actual results. After long-term operation, the prediction error can be controlled within a certain range. Within.

[0264] The following experiment will verify this:

[0265] Comparative method (traditional control method): Loading → Processing → Unloading are executed sequentially.

[0266] Total beat satisfy:

[0267]

[0268] Substitute parameters: , , ;

[0269]

[0270] The method of this invention (using cycle-linked control):

[0271] Because the feeding action is hidden within the processing cycle, the total cycle time is... satisfy:

[0272]

[0273]

[0274] In summary, this invention, by constructing a processing time prediction model and a cycle time linkage control mechanism, enables the coordinated operation of the material loading station, processing station, and palletizing station, effectively reducing equipment waiting time and improving the production efficiency and equipment utilization rate of laser drilling of automotive galvanized steel pipes.

Claims

1. A method for controlling the cycle time of laser drilling of galvanized steel pipes for automobiles based on prediction of remaining processing time, characterized in that, Includes the following steps: Step S1: The loading robot places the galvanized steel pipes for automobiles into the positioning fixture; Step S2: The central control system reads the machining program for the corresponding model and generates a machining task queue; Step S3: The laser drilling robot moves sequentially to each target hole position according to the preset trajectory to perform laser drilling processing; Step S4: The central control system establishes a prediction model for the remaining processing time based on the number of unfinished slots, the number of unfinished waist holes, the length of the slots, the length of the waist holes, the laser scanning speed, and the remaining movement time of the robot, and calculates the remaining processing time of the current workpiece. Step S5: The central control system acquires the preparation time of the feeding robot and performs cycle time linkage condition determination. Step S6: When the preset linkage conditions are met, the loading robot grabs the next workpiece to be processed in advance and moves to the preset hovering waiting position to maintain the grabbing state. Step S7: After the current workpiece is processed, the unloading robot will transport the processed workpiece to the finished product area; Step S8: The loading robot places the workpiece to be processed into the positioning fixture and starts the next processing cycle.

2. The laser drilling cycle control method for automotive galvanized steel pipes based on remaining processing time prediction according to claim 1, wherein step S1 includes: S11. The central control system receives the production start command and sends material picking task information to the material loading robot; wherein, the material picking task information includes: workpiece number to be processed, workpiece model, material picking position coordinates, and target placement position coordinates; S12. After receiving the material handling task, the loading robot moves to the material bin to be processed according to the preset motion trajectory; the robot control system calls the corresponding teaching program, and the robot end gripper moves to the preset gripping position above the galvanized steel pipe to be processed. S13. The loading robot controls the gripper to perform a clamping action. After the gripper contacts the galvanized steel pipe of the car, it forms a stable grip and confirms the successful gripping by the gripping status detection signal. If the detection result is abnormal, an alarm signal is sent to the central control system and the gripping action is re-executed. S14. After the loading robot completes the gripping, it lifts the galvanized steel pipe to a safe height to avoid interference between the robot and the hopper or clamps during the handling process; the central control system monitors the robot's current position and operating status in real time. S15. The loading robot transports the galvanized steel pipes for automobiles to the laser processing station according to the preset transport trajectory. During the transport process, the robot control system executes path planning based on the taught trajectory. S16. After the loading robot reaches the preset placement position above the positioning fixture, it descends according to the taught coordinates; the galvanized steel pipe of the automobile is placed on the support surface of the positioning fixture; the positioning fixture includes a fixture base plate, an axial positioning block, a radial support block, and a cylinder clamping mechanism. The axial positioning block is used to determine the axial position of the workpiece, and the radial support block is used to determine the radial position of the workpiece. S17. After receiving the workpiece arrival signal, the positioning fixture controls the cylinder clamping mechanism to perform the clamping action; the cylinder pushes the clamping block to move towards the galvanized steel pipe of the automobile, completing the workpiece fixation; the positioning of the fixture and the clamping of the cylinder are combined to ensure that the workpiece does not move during the processing. S18. After the fixture is clamped, a clamping completion signal is sent to the central control system. The central control system confirms that the workpiece is in a processable state and then proceeds to step S2.

3. The laser drilling cycle control method for automotive galvanized steel pipes based on remaining processing time prediction according to claim 1, characterized in that, Step S2 includes: S21. The central control system receives the clamping completion signal sent by the positioning fixture. When the central control system confirms that the workpiece has been in place, the fixture has been clamped, and the processing station is in an idle state, the processing task preparation process is started. S22. The central control system reads the current production order information, obtains the product model, product batch, processing program number, and process parameter number, and then automatically matches the corresponding processing program according to the product model. S23. The central control system reads the hole position information corresponding to the automotive pipe fitting. The hole position information includes hole position number, hole position coordinates, hole position type, processing sequence, and laser parameters, which are used to form processing task nodes. S24. The central control system establishes a hole type attribute table based on the hole position type, where slotted holes are defined as the first hole type and waist holes are defined as the second hole type, and records the length of the slotted holes respectively. Waist hole length This is used for predicting and calculating the remaining processing time. S25. The central control system generates a processing task queue based on the hole position coordinate information, and records the current task number, the number of completed tasks, and the number of uncompleted tasks for real-time processing status tracking. S26. The central control system automatically generates the robot's motion trajectory based on the hole distribution. Specifically, this includes acquiring the three-dimensional coordinates of all holes, calculating the distance between adjacent holes, establishing a set of motion paths, generating a sequence of robot trajectory points, generating processing posture parameters, generating trajectory switching points, generating avoidance action paths, and completing trajectory planning. S27. The central control system sends processing parameters to the laser, including laser power, laser on-time, laser off-time, scanning speed, and processing mode. S28. The central control system completes the initialization of the machining task; it establishes the current workpiece machining status variables, including the current workpiece number, total number of holes, number of completed holes, number of remaining holes, current machining hole position, and number of remaining slot holes. Number of remaining waist holes Simultaneously, a remaining processing time prediction buffer is established for real-time calculation of the remaining processing time in subsequent step S4. After initialization, the central control system sends a processing start command to the laser drilling robot and proceeds to step S3.

4. The laser drilling cycle control method for automotive galvanized steel pipes based on remaining processing time prediction according to claim 1, characterized in that, Step S3 includes: S31. The laser drilling robot receives the processing start command sent by the central control system; the robot controller reads the processing task queue, obtains the current workpiece number, hole number, hole coordinates, hole type, and laser processing parameters, and completes the processing task initialization; then the robot moves from the safe waiting position to the processing start point of the first hole. S32. The robot moves to the target hole according to the preset trajectory; during the movement, the robot controller performs coordinate transformation, posture adjustment, path interpolation, and speed planning in real time to ensure that the laser processing head always remains perpendicular to the workpiece surface or at a preset angle. S33. After the robot reaches the hole processing position, the central control system sends a laser start command to the laser. The laser outputs a laser beam, which is focused by the laser processing head and acts on the surface of the galvanized steel pipe of the car to form the initial piercing point. At the same time, the system records the hole processing start time as the basis for subsequent processing time statistics. S34. Perform the corresponding processing action according to the hole type; when the hole type is a slot: the robot performs laser cutting according to the slot contour trajectory; The length of the slot is Corresponding theoretical scanning time for: in This refers to the laser scanning speed; After completing the slot contour cutting, turn off the laser. S35. When the hole type is a waist hole: the robot performs laser cutting according to the contour trajectory of the waist hole; The length of the waist hole is Corresponding theoretical scanning time for: After completing the waist hole contour cutting, turn off the laser; S36. After each hole is machined, the central control system updates the machining status database in real time, including the number of completed holes, the number of remaining holes, the currently machined hole, and the number of remaining slots. Number of remaining waist holes Simultaneously, the processing time of a single hole, the robot's movement time, and the laser's start and stop time are recorded, and the recorded data is written to the processing buffer in real time. S37. After the robot completes the current hole position, it automatically moves to the next hole position. The system executes the following process: Obtain the coordinates of the next hole, calculate the distance between the current position and the target position, generate the movement trajectory, execute the robot movement, reach the target position, adjust the processing posture, confirm that the processing conditions are met, and start processing of the next hole; The above process is repeated until all holes are machined. S38. After all holes in the machining task queue are completed, the central control system confirms... and At this point, it is determined that the current workpiece processing is complete; then, the following steps are executed: turning off the laser output, saving the processing record, updating the workpiece status, sending a processing completion signal to the PLC, the robot returning to the safe waiting position, waiting for the unloading robot to enter the workstation, allowing the fixture to perform the release action, and then proceeding to step S4.

5. The laser drilling cycle control method for automotive galvanized steel pipes based on remaining processing time prediction according to claim 1, characterized in that, Step S4 includes: S41. Obtain the current workpiece processing status information. The central control system reads the processing status buffer data in real time to obtain the current workpiece number, current processing hole number, number of completed holes, number of remaining holes, current robot coordinates, and current processing progress. At the same time, it confirms whether the current processing task is in normal operation. If an emergency stop, alarm, or laser failure is detected, the remaining time prediction calculation is paused. S42. The central control system traverses the processing task queue, identifies unfinished slotting tasks, and counts the number of remaining slots. The calculation formula is: in: This represents the total number of slots. This represents the number of slots that have been completed. S43. The central control system continues to traverse the task queue, identifies unfinished waist hole tasks, and counts the remaining waist hole tasks. The calculation formula is: in This represents the total number of lumbar perforations. The number of completed waist holes; S44. The central control system calculates the remaining laser processing time based on the remaining hole position information. Considering the different processing times for different hole types, a hole type weighting coefficient is introduced, where the weight for slot holes is... The weight of the waist hole is ; Remaining scan time The calculation formula is: in The length of the slot; The length of the waist hole; The laser scanning speed is used to obtain the theoretical processing time for the remaining holes using the above formula. S45. The central control system reads the robot's current position and obtains the coordinates of the remaining holes according to the processing task queue. Then it executes the following steps: obtain the current robot position, obtain the next target hole, obtain the coordinates of all subsequent holes, establish a set of remaining paths, calculate the distance between adjacent holes, generate the remaining trajectory sequence, accumulate the total length of all remaining paths, and obtain the total remaining motion distance. S46. Calculate the robot's remaining motion time. The central control system calculates the robot's remaining motion time based on the remaining path length, using the following formula: in For the remaining trajectory, the first Segment path length; The average speed of the robot; S47. The central control system adds the remaining scanning time to the remaining motion time to obtain the total remaining processing time for the current workpiece. The calculation formula is as follows: + Right now: in Indicates the remaining processing time for the current workpiece; After the results are generated, they are written into the real-time data area of ​​the central control system and simultaneously sent to the cycle linkage control module. S48. The central control system establishes a processing time database, which records the actual processing time, actual robot movement time, actual cycle time, and product model information. set up To predict the time, For actual time, prediction error Defined as: when At that time, the central control system automatically corrects. and This allows the predicted results to gradually approach the actual processing time; after continuous production operation, the prediction error is controlled within... Within.

6. The laser drilling cycle control method for automotive galvanized steel pipes based on remaining processing time prediction according to claim 1, characterized in that, Step S5 includes: S51. The central control system receives the remaining processing time data output in step S4 and reads the remaining processing time of the current workpiece in real time. This includes the remaining laser scanning time and the remaining robot movement time; S52. The central control system reads the operating status of the loading robot and determines whether the robot is in an idle state, a task execution state, a fault state, a pre-loading state, or a hovering waiting state. If the robot is in a fault state, the cycle linkage control is paused. If the robot is idle, the linkage judgment is allowed to continue. S53. The central control system reads the time required for the loading robot to grasp the workpiece, including the robot moving to the hopper, gripper positioning, gripper closing, grasp confirmation, workpiece lifting, detachment from the hopper, posture adjustment, and entry into the handling state. The above time is defined as: loading and grasping time. ; S54. The central control system calculates the time required for the loading robot to move the workpiece from the hopper to the hovering waiting position, including the robot's acceleration time, constant speed movement time, deceleration time, and attitude adjustment time, defined as: loading and handling time. ; S55, the central control system adds the grabbing time and the handling time together to obtain the material preparation time. : + This indicates the time required from receiving the pre-loading instruction to the robot completing the grabbing and reaching the hovering waiting position; S56. Execute cycle time linkage determination, and the central control system reads the safety margin coefficient. Then, the linkage judgment algorithm is executed: when the judgment condition is met, it means that the remaining processing time of the current workpiece is less than or equal to the preparation time of the loading robot; if the loading action is started immediately, the robot can complete the preparation of the next workpiece before the current workpiece is finished. S57. Determine the rhythm linkage condition: when Continue processing and maintain the current state; when It allows pre-loading and sends a trigger signal to the PLC linkage module, while locking the workpiece linkage state to avoid repeated triggering of the pre-loading action; S58. When the linkage conditions are met, the central control system sends a pre-loading instruction to the loading robot. The instruction includes the workpiece number, picking coordinates, hovering waiting coordinates, and transport trajectory number. After receiving the instruction, the loading robot immediately executes the next workpiece grabbing action and enters step S6. At the same time, the laser drilling robot continues to process the current workpiece, and the unloading robot remains in standby state, forming a three-robot parallel collaborative working mode.

7. The laser drilling cycle control method for automotive galvanized steel pipes based on remaining processing time prediction according to claim 1, characterized in that, Step S6 includes: S61. When the linkage judgment condition in step S5 is met, the central control system sends a pre-loading instruction to the loading robot. The pre-loading instruction includes: the workpiece number to be grabbed, the coordinates of the hopper, the grabbing posture parameters, the hovering waiting coordinates, and the motion trajectory number. After receiving the pre-loading instruction, the loading robot immediately enters the pre-loading working mode. At the same time, the central control system records the pre-loading start time as the basis for subsequent cycle count statistics. S62. The loading robot moves to the processing bin according to the preset trajectory, and then performs the following actions: the robot moves to the gripping preparation position, the end gripper opens, the robot descends to the gripping height, the gripper closes to clamp the workpiece, the gripping status is detected, and the next automotive pipe to be processed is successfully gripped; if the gripping detection fails, the gripping process is repeated; after the number of consecutive failures reaches a preset number, an abnormal alarm signal is sent to the central control system. S63. After successful grabbing, the loading robot lifts the workpiece to a safe height and then moves to a hovering waiting position according to a preset trajectory. The hovering waiting position is set outside the safe area above the positioning fixture and avoids the laser robot's movement area, the unloading robot's movement area, and the laser processing area. The central control system monitors the robot position, workpiece status, and safe area status in real time to ensure that no movement interference occurs during the operation of each robot. S64. When the robot reaches the hovering waiting position, it maintains its current posture and continues to hold the workpiece, entering the hovering buffer state. At this time, the workpiece has been grasped, the workpiece has been transported, and the workpiece is in the waiting-to-load state, but it will not immediately enter the processing station. The central control system continuously monitors the processing completion signal, the fixture status signal, and the unloading completion signal, waiting for the workpiece switching conditions to be met. S65. When the current workpiece is finished, the fixture is released, and the unloading robot has finished unloading, the central control system generates a material change execution command; the material change execution command is sent to the loading robot. After receiving the command, the loading robot exits the hovering waiting state and starts the workpiece switching program. S66. The loading robot moves to the top of the positioning fixture according to the preset trajectory and performs the following actions: adjusts the placement posture, descends to the placement position, releases the workpiece, the fixture performs cylinder clamping, confirms clamping completion, and sends a loading completion signal to the central control system.

8. The laser drilling cycle control method for automotive galvanized steel pipes based on remaining processing time prediction according to claim 1, characterized in that, Step S7 includes: S71. After the laser drilling robot completes the machining of all holes, the central control system receives the machining completion signal and simultaneously confirms: Current workpiece status = Machining completed, number of remaining slots / holes... Number of remaining waist holes The laser status is off, and the laser robot status is safe waiting. The central control system generates a material unloading task and sends a material unloading instruction to the material unloading robot. The material unloading instruction includes: workpiece number, workpiece position coordinates, gripping posture parameters, finished product area target coordinates, and material unloading trajectory number. S72. The central control system sends an unlocking command to the positioning fixture, and the fixture cylinder performs a retraction action to release the clamping of the galvanized steel pipe for automobiles. Specifically, this includes: closing the clamping holding signal, retracting the cylinder, withdrawing the clamping block, releasing the workpiece from constraint, detecting the open position of the fixture, and sending a fixture release completion signal to the PLC. The system only allows the unloading robot to enter the workstation after the fixture is fully opened. S73. After receiving the clamp release signal, the unloading robot moves to the workpiece gripping position according to the preset trajectory. Specifically, this includes: moving to the gripping preparation position, adjusting the gripping posture, opening the gripper, descending to the gripping height, closing the gripper to clamp the workpiece, and detecting the gripping status. When the gripping is successful, the robot raises the workpiece to a safe height. S74. After the unloading robot grabs the workpiece, it moves towards the finished product area along the preset trajectory. During the handling process, the central control system monitors in real time: robot coordinates, workpiece status, and interference area status to ensure that there is no motion interference with the laser drilling robot and the loading robot. At the same time, the PLC continuously executes safety interlock judgment. When an abnormal situation is detected, it immediately triggers a deceleration or stop command. S75. After the unloading robot arrives at the finished product area, it performs the unloading action, which includes: descending to the unloading position, opening the gripper, releasing the workpiece, confirming that the workpiece is detached from the gripper, the robot returning to a safe height, and sending an unloading completion signal to the central control system. At the same time, the central control system updates the production database, recording the following information: workpiece number, product model, processing start time, processing end time, processing cycle, equipment operating status, and production batch information, for subsequent production statistics and cycle time analysis. S76. After receiving the unloading completion signal, the central control system performs workpiece switching judgment. When the following conditions are met: unloading is completed, the fixture is in the open state, the loading robot is in the hovering waiting state, and the next workpiece is ready, a loading permission signal is generated and sent to the loading robot. At this time, the loading robot immediately exits the hovering waiting state and executes the next workpiece loading action.

9. The laser drilling cycle control method for automotive galvanized steel pipes based on remaining processing time prediction according to claim 1, characterized in that, Step S8 includes: S81. The central control system receives the loading completion signal sent by the loading robot, and at the same time reads the fixture status information to confirm that the workpiece has been placed, the fixture has been clamped, the positioning status is normal, and the robot has left the workstation. When all the above conditions are met, it is determined that the next workpiece has entered the waiting state and proceeds to the next step. S82. The central control system reads the machining program corresponding to the current workpiece, establishes a new machining task data area, and initializes the following information: workpiece number, product model, total number of holes, number of completed holes, number of remaining holes, number of slot holes, number of waist holes, and machining start time. S83. The central control system re-establishes the time prediction parameters based on the current workpiece processing information, specifically including: initializing the number of remaining slots. Initialize the number of remaining waist holes Initialize hole shape weight coefficients, initialize robot trajectory data, establish remaining path model, establish remaining processing time prediction model, and re-enter step S4; S84. The central control system sends a processing start command to the laser drilling robot. After receiving the command, the robot executes the following: enters the processing preparation state, moves to the first hole position, adjusts the processing posture, the laser enters the standby state, establishes the processing coordinate system, and starts processing at the first hole position. This completes the start of processing a new workpiece. S85. The central control system writes the production data of the previous workpiece into the production database. The recorded content includes: workpiece number, processing cycle, loading time, processing time, unloading time, cycle time, robot running time, and equipment utilization rate. At the same time, it generates: shift statistics, daily output statistics, and equipment efficiency statistics for subsequent production management and cycle time optimization analysis. S86. When a new workpiece begins processing, the central control system re-enters step S3 until the production order is completed, production is manually stopped, or a system failure occurs, at which point the system exits the cyclic operation mode.

10. A laser drilling cycle linkage control system for automotive galvanized steel pipes based on remaining processing time prediction, characterized in that, This system is used to implement the laser drilling cycle linkage control method for automotive galvanized steel pipes based on the prediction of remaining processing time, as described in any one of claims 1 to 9, specifically including: The loading robot is used to grab galvanized steel pipes for automobiles and place them in positioning fixtures, and to grab the next workpiece to be processed in advance and move it to a preset hovering waiting position after receiving a pre-loading instruction; A laser drilling robot is used to move sequentially to each target hole according to a preset trajectory to perform laser drilling on the galvanized steel pipe of the automobile. The unloading robot is used to transport the processed workpieces to the finished product area; A positioning clamp is used to fix the galvanized steel pipe used in the automobile; The central control system is communicatively connected to the loading robot, the laser drilling robot, and the unloading robot, respectively. The central control system is used to read the processing program to generate a processing task queue, establish a remaining processing time prediction model based on the number of unfinished slots, the number of unfinished waist holes, the length of the slots, the length of the waist holes, the laser scanning speed, and the remaining movement time of the robot to calculate the remaining processing time of the current workpiece, obtain the preparation time of the loading robot and execute the cycle linkage judgment, and send a pre-loading instruction to the loading robot when the linkage condition is met.

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