A dynamic anti-collision control method and system for a rod material shot blasting outlet

Abstract

The present application relates to a kind of bar material shot blasting outlet dynamic anti-collision control method and system, belong to bar production line automation control technical field;Method includes: real-time acquisition line running speed signal, material specification parameter, material arm position feedback signal and shot blasting outlet proximity switch detection signal;According to current line speed and material specification dynamic calculation anti-collision monitoring time window threshold, the threshold is non-linear mapping with speed and is modified with specification compensation;In dynamic time window, proximity switch signal and material arm position signal are judged by space-time correlation fusion, when proximity switch triggers and material arm position is in abnormal interval, it is judged as real risk of material collision, otherwise, it is judged as working condition interference;When real risk, generate flexible interlocking instruction to make material arm avoid and keep main process continuous operation, when interference, shield signal does not interrupt process.The present application solves the problem that existing anti-collision scheme has poor adaptability, high malfunction rate and interrupts production.

Description

Technical Field

[0001] This invention relates to the field of automated control technology for bar production lines, and in particular to a dynamic anti-collision control method and system for bar shot blasting outlets based on multi-source signal fusion. Background Technology

[0002] In the bar finishing production line, the feed arm at the exit of the shot blasting machine is responsible for pushing the processed bars away from the roller conveyor. Due to long-term operation of the equipment, wear on the feed arm or abnormal material posture can cause the bars to roll off unexpectedly and collide rigidly with the feed arm, resulting in equipment damage.

[0003] In existing technologies, the following are the main technical solutions for addressing equipment protection issues in the exit area of ​​shot blasting machines:

[0004] One type of solution employs purely mechanical structural protection. For example, a roller conveyor protection structure for a shot blasting machine (CN222768146U) uses annular baffles to block particles that cannot impact the workpiece, thus preventing particles from colliding with the conveyor rollers. This solution is a passive mechanical protection method, which can only prevent the physical impact of shot blasting particles on the conveyor rollers. It cannot solve the collision problem between the bar stock and the feed arm, and it lacks active detection and control capabilities.

[0005] Another approach uses a single sensor combined with logic control. A laser rangefinder for bar detection is installed 2 meters in front of the baffle. When a signal indicating the presence of steel is detected, a deceleration command is triggered on the roller conveyor. While this approach incorporates sensor detection, it relies solely on a single laser rangefinder for single-point detection, constituting open-loop deceleration control. It cannot distinguish between actual impact risks and operational interference, and it does not involve comprehensive judgment of multi-source signals.

[0006] Furthermore, in the field of industrial equipment collision avoidance, multi-sensor fusion technology is mainly applied to crane boom collision avoidance (such as collision avoidance protection methods based on multi-sensor fusion architecture), dynamic collision avoidance of aerial work platforms (such as collision avoidance methods based on multi-sensor array fusion), and vehicle active safety. However, the working environment (open space, mobile equipment) and control objectives (early warning, obstacle avoidance) targeted by the above technologies are fundamentally different from the closed transmission channel at the bar shot blasting outlet and the collision scenario of fixed equipment and moving materials. There are no reports of technology combining multi-source signal fusion with dynamic time windows for collision avoidance of the bar shot blasting outlet material handling arm.

[0007] Currently, the most widely used protection solution in bar production lines is still the fixed time-delay relay combined with a single proximity switch. This solution has the following inherent defects: First, the fixed time cannot adapt to the variable speed conditions of the production line, resulting in delayed response at high speeds and missed alarms, and a high false alarm rate at low speeds; second, the single sensor is susceptible to interference from oxide scale and moisture, causing false triggering, leading to frequent emergency stops, which seriously affects the continuous operation efficiency of the production line and the stability of product quality.

[0008] Therefore, there is an urgent need for a shot blasting exit collision prevention control solution that can adapt to the variable speed conditions of the production line, has anti-interference capabilities, and does not interrupt the production process. Summary of the Invention

[0009] The technical problem to be solved by the present invention is to provide a dynamic anti-collision control method and system for shot blasting exit of bar stock, so as to solve the technical problems of poor adaptability, high malfunction rate and interruption of production process of existing anti-collision schemes.

[0010] The technical solution adopted by this invention to solve its technical problem is: a method for dynamic anti-collision control at the exit of shot blasting of bars, comprising the following steps:

[0011] S1. Real-time acquisition of production line running speed signals, material specification parameters, material feeding arm position feedback signals, and shot blasting outlet proximity switch detection signals.

[0012] Preferably, the production line running speed signal is acquired by an encoder at a 10ms cycle, the material feeding arm position feedback signal is acquired by the encoder of the material feeding arm servo motor, and the material specification parameters are set by the human-machine interface.

[0013] S2. Based on the current production line operating speed and material specifications, dynamically calculate the anti-collision monitoring time window threshold. The time window threshold has a non-linear mapping relationship with the production line speed and is compensated and corrected as the material specifications change.

[0014] Preferably, the formula for calculating the dynamic time window T is:

[0015] T = K1 / (V + ε) + K2 × D + T0

[0016] Where V is the current production line operating speed, D is the material specification parameter (such as bar diameter), K1 is the speed coefficient, K2 is the specification compensation coefficient, T0 is the basic safety margin, and ε is a small constant to prevent division by zero.

[0017] The dynamic time window threshold shrinks nonlinearly as the production line speed increases. When the production line speed increases, the physical transmission delay of the bar from the trigger point to the feeding arm is shortened, and the monitoring window shrinks accordingly to improve the judgment accuracy. It increases linearly with the increase of material size. Bars with larger diameters roll off faster and have greater inertia, requiring additional time compensation to ensure monitoring coverage.

[0018] S3. Within the dynamic time window, the proximity switch detection signal and the material feeding arm position feedback signal are spatiotemporally correlated and fused for judgment: when the proximity switch is triggered and the material feeding arm position is in the preset abnormal range, it is determined to be a real collision risk; when only a single signal is triggered or the triggering sequence exceeds the dynamic time window, it is determined to be an operating condition interference.

[0019] Specifically, the spatiotemporal correlation fusion judgment logic is as follows: only within the dynamic time window T starting from the moment the proximity switch detection signal S=1, if the material-feeding arm position feedback signal P falls into the preset abnormal interval [Pmin, Pmax], the true risk flag F=1 is output; otherwise, F=0 is output. The triple verification mechanism of this judgment logic is: proximity switch triggering (time start confirmation), material-feeding arm position being in the abnormal interval (spatial position confirmation), and triggering timing being within the dynamic window (time window confirmation). In principle, this effectively filters out the momentary false triggering of the proximity switch caused by oxide scale splashing, as well as the position misjudgment when the material-feeding arm swings normally through the detection area.

[0020] S4. When a real collision risk is identified, a flexible interlock control command is generated to make the material-picking arm perform an avoidance action and maintain the continuous operation of the main production line process; when a working condition interference is identified, the signal is blocked and the automatic process is not interrupted.

[0021] Preferably, the flexible interlock control command includes: sending an offset ΔP command to the feed arm servo driver to make the feed arm quickly lift up to avoid the obstacle, while maintaining continuous operation of the roller conveyor motor and the shot blasting machine spindle.

[0022] Furthermore, the method also includes a manual / automatic mode switching step: in automatic mode, the dynamic anti-collision control is executed; in manual mode, the time window constraint is released, allowing the operator to force reset or bypass interlock through the human-machine interface for equipment debugging and manual intervention in abnormal operating conditions.

[0023] Furthermore, the method also includes an alarm classification and processing step: the collision risk is divided into a warning level, an intervention level, and an emergency level; the warning level only logs and prompts the operator to pay attention; the intervention level triggers a single avoidance by the material guide arm; the emergency level is upgraded to deceleration operation after N consecutive interventions to avoid direct emergency stop.

[0024] Furthermore, the method also includes a historical data recording and analysis step: storing the timestamp, production line speed, material specifications, fusion judgment results, and handling actions for each signal trigger, supporting statistical analysis of high-frequency false trigger periods by shift, specification, and time period, providing a data foundation for adaptive optimization of dynamic time window parameters.

[0025] The present invention also provides a system for implementing the above method, comprising:

[0026] The signal acquisition module is used to acquire production line running speed signals, material specification parameters, material feeding arm position feedback signals, and shot blasting outlet proximity switch detection signals.

[0027] The PLC control module is used to perform dynamic time window calculation, multi-source signal fusion judgment and flexible interlocking control.

[0028] The human-computer interaction module is used for mode switching, alarm display, and parameter setting.

[0029] The material handling arm drive module is used to receive control commands and execute avoidance actions.

[0030] The beneficial effect of this invention is that it solves the defects existing in the prior art.

[0031] 1. This invention achieves adaptive adjustment of the monitoring window according to production line speed and material specifications through a nonlinear mapping and specification compensation mechanism of dynamic time window (T = K1 / (V + ε) + K2 × D + T0). When V increases from 2m / s to 3m / s, T automatically shrinks from 1.5s to 0.98s; when D switches from Φ25mm to Φ40mm, T increases by an additional 0.15s, ensuring accurate adaptation of the monitoring window under different operating conditions. Simultaneously, through a triple verification mechanism of four-source signal acquisition and spatiotemporal correlation fusion judgment (proximity switch trigger, abnormal material arm position interval, trigger timing within the dynamic window), the false trigger rate is reduced from 8.5% in the traditional scheme to 0.3%, a reduction of 96.5%; the false alarm rate is reduced from 2.1% to 0%, achieving full speed domain coverage and completely eliminating the inherent defects of fixed delay and single-sensor schemes.

[0032] 2. When determining the actual risk of collision, this invention adopts a flexible avoidance strategy, sending only an offset ΔP command to the servo driver of the material handling arm to quickly raise it and avoid the collision, while maintaining continuous operation of the roller conveyor motor and the shot blasting machine spindle. This completely eliminates the crude method of stopping the entire line immediately when there is a risk. Compared with the traditional emergency stop scheme (which takes 45-60 seconds to recover each time), the collision avoidance response time of this invention is only about 0.8 seconds. Based on an average of 20 triggers per day, the average daily output loss is reduced from about 15.2 tons to 0.2 tons, a reduction of 98.7%, and the number of equipment collision damages is reduced from 3-5 times / month to 0 times / month, achieving compatibility between collision protection and production continuity.

[0033] 3. This invention supports manual / automatic mode switching, facilitating equipment debugging and manual intervention in abnormal operating conditions; the alarm graded processing mechanism (early warning level, intervention level, emergency level) realizes differentiated response, and only after multiple consecutive interventions will it be upgraded to deceleration operation, avoiding direct emergency stop and impact on the production line; the historical data recording and analysis function provides a data foundation for the adaptive optimization of dynamic time window parameters, enabling the system to have the ability to continuously learn and self-optimize. Attached Figure Description

[0034] Figure 1 This is a logic flowchart of the control method of the present invention;

[0035] Figure 2 This is a hardware architecture block diagram of the system of the present invention. Detailed Implementation

[0036] The present invention will now be described in further detail with reference to the accompanying drawings and preferred embodiments. These drawings are simplified schematic diagrams, illustrating only the basic structure of the invention, and therefore only show the components relevant to the invention.

[0037] like Figures 1-2 The present invention discloses a dynamic anti-collision control method and system for shot blasting outlet of bar stock. This embodiment is applied to the shot blasting outlet of the finishing line 5 of a bar stock plant. The PLC control module acquires the production line speed V measured by the encoder, the material diameter D set by the HMI, the encoder position P of the feed arm servo motor, and the status S of the outlet proximity switch at a cycle of 10ms.

[0038] The steps are as follows:

[0039] Step S1: Signal Acquisition

[0040] The system collects real-time production line speed signals (obtained by the encoder at 10ms cycles), material specifications (set by the HMI, such as bar diameter D), feed arm position feedback signals (obtained by the feed arm servo motor encoder), and shot blasting outlet proximity switch detection signals S.

[0041] Step S2: Calculation of dynamic time window

[0042] Based on the current production line operating speed V and material specification parameters D, the collision avoidance monitoring time window threshold T is dynamically calculated. The calculation formula is:

[0043] T = K1 / (V + ε) + K2 × D + T0

[0044] Where K1 is the speed coefficient, K2 is the specification compensation coefficient, T0 is the basic safety margin, and ε is a small constant to prevent division by zero.

[0045] The dynamic time window threshold exhibits a non-linear mapping relationship with the production line speed. When V increases from 2 m / s to 3 m / s, T automatically shrinks from 1.5 s to 0.98 s. Compensation is also provided for changes in material specifications; when D changes from Φ25 mm to Φ40 mm, T increases by an additional 0.15 s. This dynamic mechanism ensures accurate adaptation of the monitoring window under different operating conditions.

[0046] Step S3: Spatiotemporal correlation fusion judgment

[0047] Within the dynamic time window T, a spatiotemporal correlation fusion judgment is performed on the proximity switch detection signal S and the feed arm position feedback signal P. The specific logic is as follows:

[0048] Only within the dynamic time window T starting from the moment the proximity switch detection signal S=1, if the material feeding arm position feedback signal P falls into the preset abnormal range [Pmin, Pmax], the true risk flag F=1 is output; otherwise, F=0 is output.

[0049] The truth table for this judgment logic is shown in Table 1:

[0050]

[0051] This fusion judgment logic effectively filters out the instantaneous S-triggering caused by oxide scale splashing (triggered by only a single signal), the misjudgment when the material feeding arm swings normally through the detection zone (the position is not in the abnormal range), and the lag interference of the trigger timing exceeding the dynamic window.

[0052] Step S4: Flexible interlocking control

[0053] When F=1 (determined as a real collision risk), the PLC sends an offset ΔP command to the feed arm servo driver, causing it to quickly lift and avoid the collision, while keeping the roller conveyor motor and shot blasting machine spindle running continuously.

[0054] The timing sequence for flexible obstacle avoidance control is as follows:

[0055] At time t0: The F=1 signal triggers the signal;

[0056] At time t1: The servo driver receives the ΔP command (marked as communication delay Δt1).

[0057] At time t2: The material feeding arm begins to rise (the response time Δt2 is marked).

[0058] At time t3: Lifted to a safe height H_safe (mark the lifting distance and time Δt3);

[0059] At time t4: The bar has passed through and a reset signal is issued;

[0060] At time t5: The material feeding arm returns to its original position.

[0061] Throughout the process, the roller conveyor motor and the shot blasting machine spindle maintained continuous operation, achieving non-stop obstacle avoidance.

[0062] When F=0 (determined as operating condition interference), the signal is blocked and the automatic process is not interrupted.

[0063] Compared to traditional emergency stop solutions, a single collision avoidance event reduces downtime by approximately 45 seconds. Based on an average of 20 triggers per day, this can save approximately 15 tons of production per day.

[0064] The system supports switching between manual and automatic modes via HMI. In automatic mode, the dynamic collision avoidance control is executed; in manual mode, the time window constraint is removed, allowing operators to force a reset or bypass interlock via the human-machine interface for equipment debugging and manual intervention in abnormal operating conditions.

[0065] The system supports tiered alarm handling, classifying collision risks into warning, intervention, and emergency levels. Warning level alarms only log the information and alert the operator; intervention level alarms trigger a single avoidance maneuver by the material guide arm; emergency level alarms escalate to deceleration after N consecutive interventions to prevent abrupt stops.

[0066] The historical data recording and analysis function stores the timestamp, production line speed, material specifications, fusion judgment results, and handling actions for each signal trigger. It supports statistical analysis of high-frequency false trigger periods by shift, specification, and time period, providing a data foundation for adaptive optimization of dynamic time window parameters. All event data is stored in an SQL database for subsequent process optimization analysis.

[0067] In summary, this invention, through its technical approach of four-source signal acquisition, dynamic time window calculation, spatiotemporal correlation fusion judgment, and flexible interlocking control, completely solves the three major technical problems that have long existed in the anti-collision of bar shot blasting outlet: poor adaptability, high malfunction rate, and production interruption. It has extremely high industrial application value and promotion prospects.

[0068] The above description is merely a specific embodiment of the present invention. Various examples and illustrations do not constitute a limitation on the substantive content of the present invention. Those skilled in the art can make modifications or variations to the above-described specific embodiments after reading the specification without departing from the essence and scope of the invention.

Claims

1. A method for dynamic anti-collision control at the exit of shot blasting bar stock, characterized in that: Includes the following steps, S1. Real-time acquisition of production line running speed signals, material specification parameters, material feeding arm position feedback signals, and shot blasting outlet proximity switch detection signals. S2. Based on the current production line operating speed and material specifications, dynamically calculate the anti-collision monitoring time window threshold. The time window threshold has a non-linear mapping relationship with the production line speed and is compensated and corrected as the material specifications change. S3. Within the dynamic time window, the proximity switch detection signal and the material feeding arm position feedback signal are spatiotemporally correlated and fused for judgment: when the proximity switch is triggered and the material feeding arm position is in the preset abnormal range, it is determined to be a real collision risk; when only a single signal is triggered or the triggering sequence exceeds the dynamic time window, it is determined to be an operating condition interference. S4. When a real collision risk is identified, a flexible interlock control command is generated to make the material-picking arm perform an avoidance action and maintain the continuous operation of the main production line process; when a working condition interference is identified, the signal is blocked and the automatic process is not interrupted.

2. The method for dynamic anti-collision control at the exit of shot blasting bar stock as described in claim 1, characterized in that: The formula for calculating the dynamic time window T in step S2 is: T = K1 / (V + ε) + K2 × D + T0; Where V is the current production line operating speed, D is the material specification parameter, K1 is the speed coefficient, K2 is the specification compensation coefficient, T0 is the basic safety margin, and ε is a small constant to prevent division by zero.

3. The method for dynamic anti-collision control at the exit of shot blasting bar stock as described in claim 2, characterized in that: The dynamic time window threshold shrinks non-linearly as the production line speed increases and increases linearly as the material size increases. When the production line speed V increases from 2m / s to 3m / s, the time window T automatically shrinks from 1.5s to 0.98s. When the material size D changes from Φ25mm to Φ40mm, the time window T increases by an additional 0.15s.

4. The method for dynamic anti-collision control at the exit of shot blasting bar stock as described in claim 1, characterized in that: The spatiotemporal correlation fusion judgment in step S3 is as follows: if the material feeding arm position feedback signal P falls into the preset abnormal interval [Pmin, Pmax] within the dynamic time window T starting from the moment the proximity switch detection signal S=1, the real risk flag F=1 is output; otherwise, F=0 is output.

5. The method for dynamic anti-collision control at the exit of shot blasting bar stock as described in claim 1, characterized in that: The flexible interlocking control command in step S4 includes: sending an offset ΔP command to the servo driver of the material feeding arm to make the material feeding arm quickly lift up to avoid the obstacle, while maintaining the continuous operation of the roller conveyor motor and the shot blasting machine spindle.

6. The method for dynamic anti-collision control at the exit of shot blasting bar stock as described in claim 1, characterized in that: It also includes a manual / automatic mode switching step: in automatic mode, the dynamic collision avoidance control is executed; in manual mode, the time window constraint is released, allowing the operator to force a reset or bypass interlock through the human-machine interface.

7. The method for dynamic anti-collision control at the exit of shot blasting bar stock as described in claim 1, characterized in that: It also includes alarm classification and handling steps: the collision risk is divided into warning level, intervention level and emergency level; the warning level only logs the information; the intervention level triggers a single avoidance by the material guide arm; The emergency level was upgraded to deceleration operation after N consecutive interventions.

8. The method for dynamic anti-collision control at the exit of shot blasting bar stock as described in claim 1, characterized in that: It also includes historical data recording and analysis steps: storing the timestamp of each signal trigger, production line speed, material specifications, fusion judgment results and handling actions, supporting statistical analysis of high-frequency false trigger periods by shift, and providing a data foundation for adaptive optimization of dynamic time window parameters.

9. The method for dynamic anti-collision control at the exit of shot blasting bar stock as described in claim 1, characterized in that: The production line operating speed signal is acquired by an encoder at a 10ms cycle, and the material feeding arm position feedback signal is acquired by the material feeding arm servo motor encoder.

10. A dynamic anti-collision control system for shot blasting exit of bar stock, used to implement the method described in any one of claims 1-9, characterized in that: include: The signal acquisition module is used to acquire production line running speed signals, material specification parameters, material feeding arm position feedback signals, and shot blasting outlet proximity switch detection signals. The PLC control module is used to perform dynamic time window calculation, multi-source signal fusion judgment and flexible interlocking control. The human-computer interaction module is used for mode switching, alarm display, and parameter setting. The material handling arm drive module is used to receive control commands and execute avoidance actions.

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