A mounting height correction method and device, electronic equipment and storage medium

Abstract

The embodiment of the application discloses a mounting height correction method and device, electronic equipment and storage medium, and relates to the technical field of surface mounting equipment control, wherein the method comprises the following steps: controlling the mounting head to move to the pressure sensor directly above, measuring the vertical distance from the laser to the surface of the sensor, controlling the suction nozzle to quickly touch and press at the first speed, then rising back to zero, slowly approaching to the light touch state at the second speed, then rising back by micro-steps at the third speed and collecting the pressure data queue, performing smoothing processing on the pressure data, monitoring the critical jump of the filtered pressure value from yes to no in real time, recording the position of the suction nozzle at the critical jump moment as the trigger distance, selecting four vertexes in the mounting area to measure the height and calculate the average value, calculating the mounting height according to the vertical distance, the trigger distance, the average height and the component thickness, and outputting the landing point instruction. The application effectively solves the problems of inaccurate mounting, poor planeness adaptability and easy false triggering of noise interference in the prior art.

Description

Technical Field

[0001] This invention relates to the field of surface mount equipment control technology, and in particular to a mounting height correction method, device, electronic device, and storage medium. Background Technology

[0002] In the field of surface mount technology (SMT), with the continuous miniaturization of chip dimensions and the increasing placement density, the pick-and-place accuracy of pick-and-place machines has become a key factor determining product quality. As the final actuator for picking up and placing components, the precise control of the placement height of the nozzle directly affects the component placement yield. Currently, the mainstream height measurement methods are divided into two categories: contact height measurement and laser height measurement. The former reads the Z-axis coordinate at the trigger point by the nozzle touching a pressure sensor, while the latter uses a laser displacement sensor to measure the target height non-contactly. However, both methods face their own technical bottlenecks in practical applications, making it difficult to meet the micron-level placement accuracy requirements.

[0003] Contact-based height measurement employs a "stop upon bottoming out" logic. Because the nozzle head inevitably undergoes microscopic elastic deformation and material hysteresis during contact with the pressure sensor surface, the recorded trigger position actually includes the deformation displacement, rather than the true physical contact zero point. This deformation error is directly transmitted to the placement process. If the recorded value is too high, the actual placement position is lower than expected, easily damaging the chip; if the recorded value is too low, the nozzle is suspended, causing component ejection or placement misalignment. While laser height measurement avoids the contact deformation problem, its measurement object is the laser reflective surface, which cannot directly obtain the mechanical state during nozzle contact, and a single laser point height measurement cannot represent the height distribution of the entire placement area.

[0004] In addition, PCB boards generally warp and deform after the reflow soldering process, and the inconsistent height of the support pins results in significant differences in the actual height of different positions in the mounting area. Single-point measurements are difficult to characterize the true height of the entire mounting surface.

[0005] Meanwhile, industrial environments are filled with various noise sources, such as motor vibrations and airflow disturbances in pneumatic systems. The instantaneous readings of pressure sensors are easily affected by interference, leading to abnormal fluctuations. If raw data is used directly for triggering, false triggers or missed triggers are highly likely. Traditional methods lack the comprehensive ability to handle these complex operating conditions, resulting in poor consistency in placement height control, which has become a key bottleneck restricting the improvement of high-density placement yield.

[0006] Therefore, there is an urgent need for a mounting height correction method that can effectively eliminate mechanical deformation errors, adaptively compensate for PCB warpage deviations, and has strong anti-interference capabilities. Summary of the Invention

[0007] The present invention provides a mounting height correction method to solve the problems of inaccurate mounting height, easy chip damage or material rejection, inability to represent the overall mounting surface height, and inaccurate trigger judgment in the prior art. The technical solution is as follows: According to one aspect of the present invention, a method for correcting mounting height includes: controlling a mounting head to move directly above a pressure sensor; measuring the vertical distance from a laser to the surface of the pressure sensor; controlling a suction nozzle to descend toward the pressure sensor at a first speed until a pressure value is detected and then stopping the descent; controlling the suction nozzle to rise a set safety distance until the pressure value returns to zero; controlling the suction nozzle to descend toward the pressure sensor at a second speed until a pressure value is detected and then rising back at a third speed, during which pressure data queues of the pressure sensor are collected within a set time window; the first speed, the second speed, and the third speed are sequentially reduced; a sliding window mean filtering algorithm is used to filter the pressure data queues; the critical jump of the pressure value from present to absent in the pressure data queues is monitored in real time; the absolute coordinate distance from the suction nozzle to the mounting area at the critical jump moment is used as the trigger distance; four vertices that meet set requirements are selected in the mounting area; the average height of the vertices is calculated; the thickness of the mounted element is obtained; the mounting height is calculated based on the vertical distance, the trigger distance, the average height, and the thickness; and a landing point command is output based on the mounting height to guide the mounting action.

[0008] In one embodiment, the mounting head is moved directly above the pressure sensor, and the vertical distance from the laser to the surface of the pressure sensor is measured through the following steps: the mounting head is moved directly above the pressure sensor to ensure that the laser's emission path is perpendicular to the surface of the pressure sensor; the laser is activated to emit a laser beam to the surface of the pressure sensor; after receiving the reflected signal, the vertical distance between the laser's output port and the upper surface of the pressure sensor is calculated; the vertical distance is used to eliminate system errors caused by differences in the laser's installation position.

[0009] In one embodiment, controlling the nozzle to descend toward the pressure sensor at a first speed until a pressure value is detected and then stopping the descent, and controlling the nozzle to rise to a predetermined safe distance until the pressure value returns to zero, is achieved through the following steps: controlling the nozzle to descend rapidly toward the surface of the pressure sensor at a first speed, and immediately stopping the descent when the nozzle touches the pressure sensor and detects the pressure value increasing from zero; controlling the nozzle to rise upwards by a preset safe distance; the safe distance is used to ensure that the nozzle is completely removed from the surface of the pressure sensor and that the pressure sensor reading returns to zero.

[0010] In one embodiment, controlling the nozzle to descend toward the pressure sensor at a second speed until a pressure value is detected, and then to rise back at a third speed, collecting pressure data queues from the pressure sensor within a set time window during the rise, is achieved through the following steps: controlling the nozzle to slowly descend toward the surface of the pressure sensor at a second speed, stopping the descent when the nozzle head lightly touches the pressure sensor again and detects the pressure value increasing from zero; controlling the nozzle to rise back up at a third speed, gradually moving the nozzle in set steps during the rise, simultaneously collecting the current reading of the pressure sensor with each step, and storing the collected pressure data sequentially into the pressure data queue within the set time window.

[0011] In one embodiment, the sliding window mean filtering algorithm is used to filter the pressure data queue through the following steps: set the window size to N, take the N most recent consecutive pressure sampling data in the pressure data queue as the analysis window, sum the N data in the analysis window and divide by N to obtain the moving average at the current time; when new sampling data is stored, remove the oldest data in the analysis window and add the new sampling data to the end of the window, so that the analysis window continues to slide forward and continuously calculates new moving averages.

[0012] In one embodiment, the critical transition of the pressure value in the pressure data queue from present to absent is monitored in real time, and the absolute coordinate distance between the nozzle and the mounting area at the critical transition moment is used as the trigger distance. This is achieved through the following steps: During the process of the nozzle rising at a third speed and continuously collecting filtered pressure data, the moment when the filtered pressure value in the pressure data queue suddenly changes from a positive value greater than zero to zero is monitored in real time, and the absolute coordinate distance between the nozzle and the mounting area at the moment when the filter value changes is used as the trigger distance. In one embodiment, four vertices meeting set requirements are selected in the mounting area, the average height of the vertices is calculated, and the thickness of the mounted element is obtained. The mounting height is calculated based on the vertical distance, trigger distance, average height, and thickness. A landing point command is output based on the mounting height to guide the picking action. This is achieved through the following steps: four vertices are selected in the mounting area according to set requirements; the four vertices must be evenly distributed in the four corners of the mounting area and surround the entire mounting area; the actual height value at each of the vertices is measured using a laser, and the arithmetic mean is calculated as the average height of the mounting surface to obtain the thickness of the current mounted element; the mounting height is obtained by subtracting the trigger distance from the vertical distance, adding the average height from the thickness, and outputting a Z-axis landing point command based on the mounting height to guide the nozzle to complete the picking action.

[0013] According to one aspect of the present invention, a mounting height correction device includes: a reference acquisition and deformation elimination module, configured to control the mounting head to move directly above a pressure sensor, measure the vertical distance from a laser to the surface of the pressure sensor, control the nozzle to descend toward the pressure sensor at a first speed until a pressure value is detected and then stop descending, and control the nozzle to rise a set safety distance until the pressure value returns to zero; and a dynamic bottoming and critical calibration module, configured to control the nozzle to descend toward the pressure sensor at a second speed until a pressure value is detected and then rise back at a third speed, and during the rise, acquire pressure data queues of the pressure sensor within a set time window. The first, second, and third speeds decrease sequentially. The mounting surface mean fitting module uses a sliding window mean filtering algorithm to filter the pressure data queue, monitors the critical transition of pressure values ​​from present to absent in the pressure data queue in real time, and uses the absolute coordinate distance from the nozzle to the mounting area at the critical transition moment as the trigger distance. The height calculation and compensation module selects four vertices in the mounting area that meet set requirements, calculates the average height of the vertices, obtains the thickness of the mounted element, calculates the mounting height based on the vertical distance, trigger distance, average height, and thickness, and outputs a landing point command based on the mounting height to guide the mounting action.

[0014] According to one aspect of the present invention, an electronic device includes at least one processor and at least one memory, wherein computer-readable instructions are stored on the memory; the computer-readable instructions are executed by one or more of the processors to cause the electronic device to implement the mounting height correction method as described above.

[0015] According to one aspect of the invention, a storage medium stores computer-readable instructions thereon, which are executed by one or more processors to implement the mounting height correction method as described above.

[0016] The beneficial effects of the technical solution provided by this invention are: In the above technical solution, this invention first controls the placement head to move directly above the pressure sensor, using the vertical distance from the laser to the sensor surface as a fixed reference to eliminate system errors caused by differences in laser installation position. Based on this, the nozzle is controlled to rapidly descend at a first speed to touch the pressure sensor and then rise back to zero, followed by a second speed to slowly approach a light-touch state, and then a third speed to rise in small steps, collecting pressure data during the rise. A sliding window mean filtering algorithm is used to smooth the pressure data, effectively filtering out noise interference from industrial vibrations and airflow disturbances. Then, the critical jump of the filtered pressure value from present to absent is monitored in real time, and the nozzle position at the critical jump moment is recorded as the trigger distance. This trigger distance accurately captures the physical zero point of complete deformation release, eliminating errors caused by micro-elastic deformation and hysteresis effects resulting from nozzle contact with the sensor. Next, the height of four vertices in the placement area is measured and the average value is calculated, effectively compensating for local height deviations caused by PCB warping and uneven support pins. Finally, the final placement height is calculated based on the vertical distance, trigger distance, average height, and component thickness, and a landing point command is output to guide the nozzle to complete the pick-up action. This achieves micron-level placement accuracy control, which not only eliminates height deviation caused by mechanical deformation but also adaptively compensates for PCB flatness errors. At the same time, it effectively resists vibration and noise interference in industrial environments, enabling the pick-up machine to complete the pick-up task more safely and stably in high-density placement scenarios. This effectively solves the problems of inaccurate placement height caused by deformation errors, poor PCB warpage adaptability, and false triggering caused by noise interference in existing technologies. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments of the present invention will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention, and those skilled in the art can obtain other drawings based on these drawings without creative effort.

[0018] Figure 1 This is a flowchart illustrating a mounting height correction method according to an exemplary embodiment; Figure 2 This is a flowchart illustrating a mounting height correction method in an application scenario; Figure 3 This is a block diagram illustrating a mounting height correction device according to an exemplary embodiment; Figure 4 This is a hardware structure diagram of an electronic device according to an exemplary embodiment; Figure 5 This is a block diagram illustrating an electronic device according to an exemplary embodiment. Detailed Implementation

[0019] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0020] Those skilled in the art will understand that, unless specifically stated otherwise, the singular forms “a,” “an,” “the,” and “the” used herein may also include the plural forms. It should be further understood that the term “comprising” as used in this disclosure means the presence of the stated features, integers, steps, operations, elements, and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof. It should be understood that when we say an element is “connected” or “coupled” to another element, it can be directly connected or coupled to the other element, or there may be intermediate elements. Furthermore, “connected” or “coupled” as used herein can include wireless connections or wireless coupling. The term “and / or” as used herein includes all or any units and all combinations of one or more associated listed items.

[0021] This invention provides a mounting height correction method that accurately eliminates microscopic elastic deformation and hysteresis errors caused by the contact between the nozzle and the sensor through laser reference acquisition, dynamic touch pressure calibration, and sliding filter critical identification. Combined with four-point mean fitting of the mounting surface, it effectively compensates for PCB warpage deviations. This achieves micron-level precise control of the mounting height, solving the problems of inaccurate mounting, poor flatness adaptability, and accidental triggering due to noise interference caused by deformation errors in existing technologies. This mounting height correction method is applicable to mounting height correction devices, which can be electronic devices. The mounting height correction method in this invention can be applied to various scenarios, such as mounting height correction.

[0022] Please see Figure 1 This invention provides a mounting height correction method, which is applicable to electronic devices.

[0023] In the following method embodiments, for ease of description, the execution subject of each step of the method is an electronic device, but this does not constitute a specific limitation.

[0024] like Figure 1 As shown, the method may include the following steps: Step 110: Control the placement head to move directly above the pressure sensor, measure the vertical distance from the laser to the surface of the pressure sensor, control the nozzle to descend toward the pressure sensor at a first speed until the pressure value is detected and then stop descending, control the nozzle to rise to a set safe distance until the pressure value returns to zero.

[0025] In one possible implementation, the mounting head is moved to a position directly above the pressure sensor to ensure that the laser's emission path is perpendicular to the pressure sensor surface. The laser is then activated to emit a laser beam onto the pressure sensor surface. After receiving the reflected signal, the vertical distance between the laser's output port and the upper surface of the pressure sensor is calculated.

[0026] In one possible implementation, the nozzle is controlled to descend rapidly toward the surface of the pressure sensor at a first speed. When the nozzle touches the pressure sensor and detects the pressure value increasing from zero, the descent is immediately stopped, and the nozzle is controlled to rise back up a preset safe distance.

[0027] The vertical distance is used to eliminate systematic errors caused by differences in the laser's installation position; the safety distance is used to ensure that the nozzle is completely detached from the pressure sensor surface and that the pressure sensor reading is zero.

[0028] Specifically, under the control of the linear motor drive system, the placement head moves along the X and Y axes until the central axis of the nozzle is precisely aligned with the center point of the pressure sensor, ensuring that the placement head is positioned directly above the pressure sensor. This alignment operation ensures that the subsequent laser beam can be incident perpendicularly on the surface of the pressure sensor, avoiding measurement deviations caused by optical path tilt.

[0029] Furthermore, after the mounting head is positioned, the laser height measurement module is activated. The laser emits a laser beam downwards to the upper surface of the pressure sensor. After the beam is reflected by the sensor surface, it is captured by the receiver. The system calculates the vertical distance between the laser's output port and the upper surface of the pressure sensor based on the laser's time of flight or phase difference, and this distance is recorded as parameter 'a'. This reference value fixes the spatial geometric relationship between the laser and the sensor, and all subsequent height calculations use this value as the starting reference, thereby eliminating systematic errors caused by inconsistent installation heights or mechanical assembly tolerances of the laser.

[0030] In the above process, the embodiments of the present invention use the vertical distance between the laser and the pressure sensor as a fixed reference parameter, so that the entire height calculation system has a unified zero-point reference system, eliminating the systematic error caused by the difference in the laser installation position, and providing an accurate and reliable starting reference for subsequent nozzle touch pressure calibration and mounting surface height measurement.

[0031] Step 120: Control the nozzle to descend toward the pressure sensor at a second speed until the pressure value is detected, and then rise back at a third speed. During the rise, collect the pressure data queue of the pressure sensor within a set time window.

[0032] In one possible implementation, the nozzle is controlled to slowly descend toward the pressure sensor surface at a second speed, and the descent stops when the nozzle head touches the pressure sensor again and detects the moment when the pressure value increases from zero.

[0033] In one possible implementation, the nozzle is controlled to rise upwards at a third speed. During the rise, the nozzle is moved step by step in a set increment. Each step is used to simultaneously collect the current reading of the pressure sensor and store the collected pressure data into the pressure data queue within a set time window.

[0034] The first speed, the second speed, and the third speed decrease in that order.

[0035] Specifically, before performing the pressure touch operation, the system first performs a zeroing operation on the current reading of the pressure sensor, forcing the pressure gauge value to zero. The purpose of this zeroing operation is to eliminate any zero-point drift that may exist in the pressure sensor itself, eliminate initial non-zero readings caused by temperature changes or residual stress from the previous operation, and ensure that all subsequent pressure detections use an absolute zero pressure state as the starting point for judgment.

[0036] Furthermore, after zeroing, the nozzle is controlled to descend rapidly towards the pressure sensor surface at a first speed. This first speed is set at a relatively high value to ensure the nozzle quickly approaches the sensor surface, shortening the overall calibration time. The system immediately stops the nozzle's descent when the nozzle head just touches the pressure sensor surface and the pressure value undergoes a sudden, instantaneous change from zero to a non-zero reading. Here, "instantaneous change from zero to a non-zero reading" refers to the critical moment when the pressure value changes from zero to the first non-zero reading; the speed of this cessation directly affects the accuracy of subsequent calibrations.

[0037] Furthermore, after the rapid pressure drop stops, the nozzle is controlled to rise upwards by a preset safety distance. This safety distance is set to ensure that the nozzle head is completely detached from the pressure sensor surface and that the pressure sensor reading returns to zero. The purpose of this zero-deformation operation is to release the microscopic elastic compression deformation of the nozzle head and pressure sensor surface caused by the impact force during the initial rapid contact, allowing the entire force measurement system to fully return to its unloaded natural state, creating a "zero-deformation" starting condition for subsequent accurate measurements.

[0038] Furthermore, after confirming that the pressure value has returned to zero, the nozzle is slowly lowered towards the pressure sensor surface at a second speed. This second speed is lower than the first speed, constituting a slow approach mode. Its design aims to gently approach the contact point again, avoiding rapid impact that could introduce additional deformation. When the nozzle head lightly touches the pressure sensor again and detects the instant the pressure value increases from zero, the system stops its descent. At this point, the nozzle and sensor are only in slight contact, with minimal contact force and no significant elastic compression deformation, thus ensuring that the current state closely approximates the true physical contact zero point.

[0039] Furthermore, after slowly approaching a stop, the nozzle is controlled to rise upwards at a third speed. This third speed is the slowest of the three, typically with a step size of 10 μm / step, belonging to an ultra-low-speed micro-stepping mode. During the rise, the nozzle moves upwards gradually at this step size, simultaneously acquiring the current reading of the pressure sensor with each step. The acquired pressure data is then stored sequentially in a pressure data queue within a set time window. The purpose of this micro-step rise sampling is to acquire high-density pressure change data near the critical region of deformation release, providing sufficient data support for subsequently accurately capturing the moment when deformation is completely released.

[0040] In the above process, the embodiments of the present invention use a multi-stage speed step-by-step control strategy of "rapidly decreasing pressure - withdrawing to zero - slowly approaching - micro-step recovery" to make the calibration result of the trigger distance b accurately reflect the physical true zero point of complete deformation release.

[0041] Step 130: The pressure data queue is filtered using a sliding window mean filtering algorithm. The critical transition of the pressure value from present to absent in the pressure data queue is monitored in real time. The absolute coordinate distance from the nozzle to the mounting area at the critical transition moment is used as the trigger distance.

[0042] In one possible implementation, the window size is set to N. The most recent N consecutive pressure sampling data in the pressure data queue are taken as the analysis window. The sum of the N data in the analysis window is divided by N to obtain the moving average at the current time. When new sampling data is stored, the oldest data in the analysis window is removed and the new sampling data is added to the end of the window, so that the analysis window keeps sliding forward and continuously calculating new moving averages.

[0043] In one possible implementation, while the nozzle rises at a third speed and continuously collects filtered pressure data, the moment when the filtered pressure value in the pressure data queue suddenly changes from a positive value greater than zero to zero is monitored in real time, and the absolute coordinate distance between the nozzle and the mounting area at that moment is used as the trigger distance.

[0044] Specifically, a sliding window mean filtering algorithm is used to smooth the collected pressure data queue. The process is as follows: a window size of N is pre-set, and the N most recent consecutive pressure samples from the pressure data queue are taken as the current analysis window. The sum of the N data points within this window is divided by N to obtain the current moving average. When new sampled data is added to the queue, the oldest data point in the analysis window is removed, and the new data is added to the end of the window, ensuring the window continues to slide forward and continuously calculates new mean values. This filtering mechanism is designed to effectively counteract various sudden noises in industrial environments, such as vibrations from motor operation, airflow disturbances from pneumatic systems, and mechanical shocks from equipment start-up and shutdown. It neutralizes sudden abnormal high or low values ​​in the pressure data through the averaging effect of other normal data within the window, resulting in a smoother and more stable pressure change curve after filtering. This avoids misjudging the true timing of pressure triggering due to noise interference at a single moment.

[0045] Furthermore, during the continuous upward movement of the nozzle at the third speed while simultaneously performing filtering, the system monitors in real time whether the pressure value in the filtered pressure data queue undergoes a critical transition from positive to negative. Specifically, it monitors the instant the filtered pressure value abruptly changes from a positive value greater than zero to zero or near zero. When this critical transition is detected, the system immediately records the absolute Z-axis coordinate position of the nozzle corresponding to the transition moment as the height measurement trigger value b. This position physically represents the point where the nozzle head has just detached from the pressure sensor surface, all micro-elastic deformation has been completely released, but it has not yet left the true zero-point position of the contact critical point. The absolute coordinate distance from the nozzle to the mounting area corresponding to this critical transition moment is used as the trigger distance. This distance parameter b is the core correction amount for eliminating deformation errors in subsequent height calculations.

[0046] In the above process, the embodiments of the present invention use a multi-segment speed step control strategy, combined with a sliding window mean filtering algorithm to effectively suppress industrial noise and accurately lock the critical jump moment, so that the calibration result of the trigger distance b accurately reflects the physical zero point of complete deformation release. This eliminates the measurement deviation introduced by micro-elastic deformation and hysteresis effect in the traditional "stop when bottoming out" method, and controls the repeatability error of the b value within a very small range, providing core data support for the accurate calculation of subsequent mounting height.

[0047] Step 140: Select four vertices that meet the set requirements in the mounting area, calculate the average height of the vertices, obtain the thickness of the mounted component, calculate the mounting height based on the vertical distance, trigger distance, average height and thickness, and output the landing point command based on the mounting height to guide the mounting action.

[0048] In one possible implementation, four vertices are selected in the mounting area according to the set requirements. The actual height value at each vertex is measured by a laser and the arithmetic mean is calculated as the average height of the mounting surface. The thickness of the currently mounted component is obtained. The mounting height is obtained by subtracting the trigger distance from the vertical distance and adding the average height to the thickness. The Z-axis landing point command is output according to the mounting height to guide the nozzle to complete the mounting action.

[0049] The four vertices must be evenly distributed at the four corners of the mounting area and surround the entire mounting area.

[0050] Specifically, a mounting area is defined on the PCB board to be mounted. Four vertices are evenly selected at the four corners of this area. The selection requirement is that the four vertices must enclose the entire mounting area, meaning the mounting position should be within the rectangular or quadrilateral area enclosed by the four vertices. The purpose of this point selection method is to ensure that the four measurement points can completely cover the spatial range of the mounting area, thereby effectively characterizing the height distribution characteristics of the entire mounting surface.

[0051] Furthermore, the height of each of the four vertices is measured using a laser altimeter module and recorded as h1, h2, h3, and h4 respectively. The measurement of each vertex uses the same laser ranging principle as in step S1 to ensure the consistency and comparability of the measurement data.

[0052] Furthermore, the height values ​​of the four vertices are summed and divided by four to obtain the arithmetic mean c = (h1 + h2 + h3 + h4) / 4. This average value is used as the average height parameter of the mounting surface. The purpose of the four-point mean fitting design is that PCB boards generally experience warping and deformation after processes such as reflow soldering, and the height of the support pins may be inconsistent. The height value of a single measuring point cannot represent the actual height distribution of the entire mounting area. By using the statistical averaging of the four vertices, extreme deviations caused by local protrusions or depressions can be effectively offset, making the average height c closer to the true overall height level of the mounting area.

[0053] Furthermore, the thickness value x of the component to be mounted is obtained from the equipment parameter database or component material information. This thickness value is usually provided by the component manufacturer or pre-entered into the system through offline measurement as a fixed parameter that must be deducted in the height calculation.

[0054] Furthermore, the theoretical landing point of the nozzle relative to the mounting surface is calculated using the formula y = a - b + c. Here, a is the vertical distance from the laser to the pressure sensor surface, b is the trigger distance obtained from dynamic pressure calibration, and c is the average height of the mounting surface. The physical meaning of this formula is: starting from a fixed laser reference a, subtracting the true zero point of the nozzle b, and adding the average height c of the mounting surface, the theoretical landing point of the nozzle tip relative to the mounting surface is obtained.

[0055] Furthermore, subtracting the component thickness x from the theoretical placement position yields the final mounting height h = a - b + cx. This calculation integrates four parameters into the final Z-axis placement command value, while also incorporating multiple correction logics, including laser reference to eliminate system errors, trigger distance to eliminate deformation errors, four-point average to eliminate warpage deviations, and component thickness to ensure appropriate mounting pressure. Based on the calculated h value, the system outputs the Z-axis placement command, precisely controlling the nozzle to descend to the target height to complete the mounting action. This ensures that the mounting pressure precisely meets the soldering or bonding requirements, preventing chip damage due to excessive pressure and avoiding poor soldering or component rejection due to insufficient pressure.

[0056] In the above process, the embodiments of the present invention select four vertices evenly in the mounting area and calculate the arithmetic mean of the height, so that the mounting surface height parameter c effectively reflects the overall height level of the entire mounting area, eliminating the local height deviation caused by PCB warping and uneven support pins, and providing a mounting surface reference that fits the actual working conditions for accurate calculation of mounting height; by integrating the vertical distance a, trigger distance b, average mounting surface height c and component thickness x into a unified height calculation formula, multiple error sources such as system installation error, mechanical deformation error, and PCB warping deviation are eliminated at the same time, and the precise Z-axis landing point command is output to guide the nozzle to complete the picking action, realizing closed-loop control of micron-level mounting accuracy, effectively solving the core pain point of chip damage or component rejection caused by inaccurate mounting height in the prior art.

[0057] Through the above process, this embodiment of the invention establishes a unified zero-point reference system by obtaining a laser reference, eliminating systematic errors caused by differences in laser installation positions; through a multi-segment speed stepwise control strategy of "fast pressure drop - retraction to zero - slow approach - micro-step recovery", combined with a sliding window mean filtering algorithm to effectively suppress industrial vibration and airflow disturbance noise, and precise locking of the critical jump moment, it accurately captures the physical zero point of complete deformation release, controlling the repeatability error of the trigger distance b within ±0.5μm, eliminating the measurement deviation introduced by the traditional "bottoming out and stopping" method due to micro-elastic deformation and hysteresis effect; by uniformly selecting four vertices in the mounting area and calculating the arithmetic mean of the height, it effectively compensates for the local height deviation caused by PCB board warping and uneven support pins; finally, by integrating the height calculation formula of four parameters—vertical distance, trigger distance, average height of the mounting surface, and component thickness—it outputs a precise Z-axis landing point command, realizing closed-loop control of micron-level mounting accuracy. This invention effectively solves the problems of inaccurate mounting height caused by deformation error, poor PCB warpage adaptability, and easy accidental triggering due to noise interference in the prior art, and significantly improves the mounting yield and operational stability of the pick-and-place machine in high-density mounting scenarios.

[0058] In one application scenario, an SMT pick-and-place machine is used as the platform. This equipment is equipped with a high-precision piezoelectric pressure sensor, a laser displacement sensor, and a linear motor drive system. The PCB board to be mounted is about to have its chips mounted. The mounting area is 20mm × 20mm, and the chip to be mounted is a QFN packaged component with a thickness of x = 0.85mm. The mounting height correction method of this invention is used for mounting height correction.

[0059] like Figure 2 As shown, the specific steps may include: Step S1: Laser reference acquisition.

[0060] Specifically, the system first controls the placement head to move along the X and Y axes until the central axis of the nozzle is precisely aligned with the center point of the pressure sensor, ensuring that the placement head is positioned directly above the pressure sensor. After the placement head is positioned, the laser height measurement module is activated. The laser emits a laser beam downwards to the upper surface of the pressure sensor, and the beam is captured by the receiver after being reflected from the sensor surface. The system calculates the vertical distance between the laser's output port and the upper surface of the pressure sensor based on the laser's time of flight. Five consecutive measurements are taken, and the average value is used to eliminate random errors from single measurements. This average value is recorded as parameter 'a', in this embodiment, a = 45.200 mm. This reference value fixes the spatial geometric relationship between the laser and the sensor, and all subsequent height calculations use this value as the starting reference.

[0061] In the above process, the embodiments of the present invention use the vertical distance between the laser and the pressure sensor as a fixed reference parameter, so that the entire height calculation system has a unified zero-point reference system, eliminating the systematic error caused by the difference in the installation position of the laser.

[0062] Step S2: Dynamic touch pressure calibration.

[0063] Specifically, the system first performs a zeroing operation on the pressure sensor, forcing the current reading to zero to eliminate the influence of the sensor's own zero-point drift. After zeroing, the system controls the nozzle to descend rapidly towards the pressure sensor surface at a first speed v1 = 50 mm / s. The system immediately stops the nozzle descent the instant the nozzle head touches the pressure sensor surface and the pressure value jumps from 0g to the first non-zero reading of 0.02g. At this moment, a certain degree of micro-elastic compression deformation has occurred between the nozzle and the sensor.

[0064] The nozzle is then raised 0.5mm to a safe distance, ensuring the pressure sensor reading returns to zero and releasing the deformation caused by the initial contact. Next, the nozzle is slowly lowered at a second speed of v2 = 10mm / s. The descent stops when the nozzle head lightly touches the sensor again and the pressure value changes from 0g to 0.01g. At this point, the contact force is minimal, and no significant deformation has occurred.

[0065] The nozzle is then controlled to rise upwards at a third speed v3 = 1 mm / s (corresponding to a step size of 10 μm / step). During the rise, the nozzle synchronously collects the current pressure reading with each step and stores it sequentially in a pressure data queue with a time window size of N = 5. The system sums the five most recent data points in the queue and divides by 5 to obtain the moving average.

[0066] During the recovery process, the queue data underwent the following changes sequentially: From step 1 to step 3, the pressure value stabilized around 0.8g; in step 4, due to airflow disturbance caused by the release of the workshop pneumatic system, an abnormal value of 1.4g was collected, but the filtered mean was (0.8+0.8+0.8+1.4+0.8) / 5=0.92g, not triggering the critical judgment; in step 5, the nozzle continued to recover, the actual pressure dropped to 0.5g, a new data point of 0.6g was stored in the queue, the oldest data point of 0.8g was removed, and the filtered mean was (0.8+0.8+1.4+0.8+0.6) / 5=0.88g; in step 6, the actual pressure dropped to 0.2g, a new data point of 0.2g was stored, the second oldest data point of 0.8g was removed, and the filtered mean was (0.8+1.4+0.8+0.6+0.2) / 5=0.76g; in step 7, the nozzle recovered further... The actual pressure is zero, and the newly collected data 0g is stored. The filtered mean is (1.4+0.8+0.6+0.2+0) / 5=0.60g, and the pressure value is still greater than zero. In step 8, the newly collected data 0g is stored again, and the filtered mean is (0.8+0.6+0.2+0+0) / 5=0.32g. In step 9, the newly collected data 0g is stored, and the filtered mean is (0.6+0.2+0+0+0) / 5=0.16g. In step 10, the newly collected data 0g is stored, and the filtered mean is (0.2+0+0+0+0) / 5=0.04g, which is close to zero but still recognizable. In step 11, the newly collected data 0g is stored, and the filtered mean changes precisely to 0g. The system recognizes the critical jump from the pressure value to zero and immediately records the corresponding absolute coordinate of the nozzle Z-axis as the trigger distance b. In this embodiment, b=22.368mm. This position precisely corresponds to the physical zero point where the nozzle head has just detached from the sensor surface and all microscopic elastic deformation has been completely released.

[0067] In the above process, the embodiments of the present invention use multi-segment speed step control combined with sliding window mean filtering algorithm to accurately lock the critical jump time with a step accuracy of 10μm, and control the calibration error of the trigger distance b within ±0.5μm, eliminating the measurement deviation introduced by the traditional method due to micro elastic deformation and hysteresis effect.

[0068] Step S3: Fitting the mean value of the mounting surface.

[0069] Specifically, a 20mm × 20mm mounting area is defined on the PCB board to be mounted. Four vertices are evenly selected at the four corners of this area, ensuring that the four vertices surround the entire mounting area. A laser height measurement module is used to measure the height of each of the four vertices, obtaining h1 = 0.102mm, h2 = 0.115mm, h3 = 0.098mm, and h4 = 0.121mm. The arithmetic mean c = (0.102 + 0.115 + 0.098 + 0.121) / 4 = 0.109mm is calculated and used as the average height parameter of the mounting surface. Since the PCB board experiences approximately 0.023mm of warping after reflow soldering, the maximum deviation of a single-point measurement reaches 0.023mm. The four-point average effectively compensates for the extreme deviations caused by local protrusions and depressions.

[0070] In the above process, the embodiments of the present invention select four vertices evenly in the mounting area and calculate the arithmetic mean of the height, so that the mounting surface height parameter c effectively reflects the overall height level of the mounting area, eliminating the local height deviation caused by PCB board warping and uneven support pins.

[0071] Step S4: Height calculation and compensation.

[0072] Specifically, the thickness x=0.85mm of the QFN chip to be mounted is obtained from the device component database. Substituting the parameters a=45.200mm, b=22.368mm, c=0.109mm, and x=0.85mm into the formula h=a-b+cx, the final mounting height h=45.200-22.368+0.109-0.850=22.091mm is calculated. Based on this calculated value, the system generates a Z-axis landing point command, controlling the nozzle to precisely descend 22.091mm from the current height to complete the mounting action. This mounting height simultaneously eliminates the combined effects of laser installation errors, nozzle contact deformation errors, and PCB board warpage deviations, ensuring that the chip is mounted to the pad with just the right pressure.

[0073] In the above process, the embodiments of the present invention integrate four parameters into a unified height calculation formula, thereby eliminating multiple error sources such as system installation error, mechanical deformation error, and PCB warpage deviation, and achieving closed-loop control of micron-level mounting accuracy.

[0074] Through the above process, this embodiment of the invention uses an SMT pick and place machine as a platform and QFN chips mounted on a 20mm×20mm PCB mounting area as a specific scenario to demonstrate the entire process of the mounting height correction method of the present invention. By obtaining the laser reference distance a=45.200mm, a unified zero-point reference was established for subsequent calculations. Through multi-segment speed stepped control—"fast pressure drop-retreat to zero-slow approach-micro-step recovery"—with a step accuracy of 10μm and a sliding window mean filtering algorithm of N=5, noise interference caused by airflow disturbance in the workshop was effectively filtered out. The critical jump moment of the pressure value from present to absent after filtering was accurately locked, and the trigger distance b=22.368mm was recorded, controlling the deformation release point calibration error within ±0.5μm. By measuring the height at the four vertices of the mounting area and calculating the mean c=0.109mm, the warping deviation of the PCB board of about 0.023mm was effectively offset. Finally, by substituting a, b, c and the chip thickness x=0.85mm into the formula h=a-b+cx, the final mounting height of 22.091mm was calculated and the Z-axis landing point command was output. The entire process achieves end-to-end precision control from baseline establishment to deformation elimination, warp compensation, and final height calculation, effectively avoiding chip damage or ejection caused by deformation errors, PCB warping, and noise interference, and ensuring high precision and high consistency in the placement process.

[0075] The following are embodiments of the apparatus of the present invention, which can be used to execute the mounting height correction method involved in the present invention. For details not disclosed in the embodiments of the apparatus of the present invention, please refer to the method embodiments of the mounting height correction method involved in the present invention.

[0076] Please see Figure 3 This invention provides a mounting height correction device 800.

[0077] The mounting height correction device 800 includes, but is not limited to: a reference acquisition and deformation elimination module 810, a dynamic bottoming and critical calibration module 830, a mounting surface mean fitting module 850, and a height calculation and compensation module 870.

[0078] The reference acquisition and deformation elimination module 810 is used to control the placement head to move directly above the pressure sensor, measure the vertical distance from the laser to the surface of the pressure sensor, control the nozzle to descend toward the pressure sensor at a first speed until the pressure value is detected and then stop descending, and control the nozzle to rise to a set safe distance until the pressure value returns to zero.

[0079] The dynamic bottoming and critical calibration module 830 is used to control the nozzle to descend toward the pressure sensor at a second speed until the pressure value is detected, and then rise back at a third speed. During the rise, the pressure data queue of the pressure sensor within a set time window is collected; the first speed, the second speed and the third speed decrease sequentially.

[0080] The mounting surface mean fitting module 850 is used to filter the pressure data queue using a sliding window mean filtering algorithm, monitor the critical jump of the pressure value from present to absent in the pressure data queue in real time, and use the absolute coordinate distance from the nozzle to the mounting area at the critical jump moment as the trigger distance.

[0081] The height calculation and compensation module 870 is used to select four vertices that meet the set requirements in the mounting area, calculate the average height of the vertices, obtain the thickness of the mounted component, calculate the mounting height based on the vertical distance, trigger distance, average height and thickness, and output the landing point command based on the mounting height to guide the mounting action.

[0082] It should be noted that the mounting height correction provided in the above embodiments is only an example of the division of the above functional modules. In actual applications, the above functions can be assigned to different functional modules as needed. That is, the internal structure of the mounting height correction device will be divided into different functional modules to complete all or part of the functions described above.

[0083] Furthermore, the mounting height correction device and mounting height correction method provided in the above embodiments belong to the same concept, and the specific way in which each module performs its operation has been described in detail in the method embodiments, and will not be repeated here.

[0084] Figure 4 A schematic diagram of the structure of an electronic device according to an exemplary embodiment is shown.

[0085] It should be noted that this electronic device is merely an example adapted to the present invention and should not be construed as providing any limitation on the scope of use of the present invention. Furthermore, this electronic device should not be interpreted as requiring or depending on having... Figure 4 One or more components of the exemplary electronic device 2000 shown.

[0086] The hardware structure of electronic devices 2000 can vary significantly due to differences in configuration or performance, such as... Figure 4 As shown, the electronic device 2000 includes: a power supply 210, an interface 230, at least one memory 250, and at least one central processing unit (CPU) 270.

[0087] Specifically, power supply 210 is used to provide operating voltage for various hardware devices on electronic device 2000.

[0088] Interface 230 includes at least one wired or wireless network interface 231 for interacting with external devices. Of course, in other examples adapted to this invention, interface 230 may further include at least one serial-to-parallel conversion interface 233, at least one input / output interface 235, and at least one USB interface 237, etc. Figure 4 As shown, this does not constitute a specific limitation.

[0089] The memory 250 serves as a carrier for resource storage and can be a read-only memory, random access memory, disk, or optical disk, etc. The resources stored on it include the operating system 251, application programs 253, and data 255, etc., and the storage method can be temporary storage or permanent storage.

[0090] The operating system 251 is used to manage and control the various hardware devices and application programs 253 on the electronic device 2000, so as to enable the central processing unit 270 to perform calculations and processing on the massive data 255 in the memory 250. It can be Windows Server™, Mac OS X™, Unix™, Linux™, FreeBSD™, etc.

[0091] Application 253 is a computer-readable instruction based on operating system 251 that performs at least one specific task, and may include at least one module ( Figure 4 (Not shown), each module may contain computer-readable instructions for the electronic device 2000. For example, the mounting height correction device can be considered as application program 253 deployed on the electronic device 2000.

[0092] Data 255 may be model information, etc., and is stored in memory 250.

[0093] The central processing unit 270 may include one or more processors and is configured to communicate with the memory 250 via at least one communication bus to read computer-readable instructions stored in the memory 250, thereby performing operations and processing on the massive amount of data 255 stored in the memory 250. For example, the mounting height correction method may be implemented by the central processing unit 270 reading a series of computer-readable instructions stored in the memory 250.

[0094] Furthermore, the present invention can also be implemented through hardware circuits or a combination of hardware circuits and software. Therefore, the implementation of the present invention is not limited to any specific hardware circuit, software, or combination thereof.

[0095] Please see Figure 5 This invention provides an electronic device 4000, which may include: a desktop computer, a laptop computer, a server, etc., with sensor recognition capabilities.

[0096] exist Figure 5 In this context, the electronic device 4000 includes at least one processor 4001 and at least one memory 4003.

[0097] The data interaction between the processor 4001 and the memory 4003 can be achieved through at least one communication bus 4002. This communication bus 4002 may include a path for transmitting data between the processor 4001 and the memory 4003. The communication bus 4002 may be a PCI (Peripheral Component Interconnect) bus or an EISA (Extended Industry Standard Architecture) bus, etc. The communication bus 4002 can be divided into an address bus, a data bus, a control bus, etc. For ease of representation, Figure 5 The bus is represented by a single thick line, but this does not mean that there is only one bus or one type of bus.

[0098] Optionally, the electronic device 4000 may further include a transceiver 4004, which can be used for data interaction between the electronic device and other electronic devices, such as sending and / or receiving data. It should be noted that in practical applications, the transceiver 4004 is not limited to one type, and the structure of the electronic device 4000 does not constitute a limitation on the embodiments of the present invention.

[0099] Processor 4001 may be a CPU (Central Processing Unit), a general-purpose processor, a DSP (Digital Signal Processor), an ASIC (Application Specific Integrated Circuit), an FPGA (Field Programmable Gate Array), or other programmable logic devices, transistor logic devices, hardware components, or any combination thereof. It can implement or execute the various exemplary logic blocks, modules, and circuits described in conjunction with the disclosure of this invention. Processor 4001 may also be a combination that implements computing functions, such as including one or more microprocessor combinations, a combination of a DSP and a microprocessor, etc.

[0100] The memory 4003 may be a ROM (Read Only Memory) or other type of static storage device capable of storing static information and instructions, RAM (Random Access Memory) or other type of dynamic storage device capable of storing information and instructions, or an EEPROM (Electrically Erasable Programmable Read Only Memory), CD-ROM (Compact Disc Read Only Memory) or other optical disc storage, optical disc storage (including compressed optical discs, laser discs, optical discs, digital universal optical discs, Blu-ray discs, etc.), magnetic disk storage media or other magnetic storage devices, or any other medium capable of carrying or storing desired program instructions or code in the form of instructions or data structures and accessible by the electronic device 4000, but not limited thereto.

[0101] The memory 4003 stores computer-readable instructions, and the processor 4001 can read the computer-readable instructions stored in the memory 4003 through the communication bus 4002.

[0102] The computer-readable instructions are executed by one or more processors 4001 to implement the mounting height correction method in the above embodiments.

[0103] Furthermore, this embodiment of the invention provides a storage medium storing computer-readable instructions, which are executed by one or more processors to implement the mounting height correction method as described above.

[0104] This invention provides a computer program product, which includes computer-readable instructions stored in a storage medium. One or more processors of an electronic device read the computer-readable instructions from the storage medium, load and execute the computer-readable instructions, thereby enabling the electronic device to implement the mounting height correction method as described above.

[0105] Compared with related technologies, the beneficial effects of the present invention are: 1. This invention can achieve micron-level mounting accuracy control. By constructing a multi-speed stepped control strategy of "fast pressure drop - retraction to zero - slow approach - micro-step recovery", the nozzle is gently contacted in the slow approach stage to avoid introducing additional deformation. In the recovery stage, the nozzle is gradually moved in an ultra-low speed micro-step manner. High-density pressure change data is obtained in the critical area of ​​deformation release. Combined with the sliding window mean filtering algorithm, sudden noises such as motor vibration and airflow disturbance in the industrial field are effectively suppressed. The nozzle Z-axis position corresponding to the critical jump moment of the filtered pressure value from present to absent is accurately locked as the trigger distance b. This position precisely corresponds to the physical zero point where the nozzle head has just left the pressure sensor surface, all micro-elastic deformation has been completely released, but has not yet left the contact critical point. Unlike the traditional "stop at bottom" method, which records values ​​containing deformation displacement due to microscopic elastic compression deformation and hysteresis effects on the nozzle head and pressure sensor surface, the trigger distance b of this invention truly reflects the physical contact zero point in the undeformed state. Combined with the precise subtraction of this parameter in the subsequent height calculation formula, the interference of deformation error on the mounting height is eliminated from the source. The repeatability error of the b value is controlled within an extremely small error range, enabling the pick-and-place machine to complete chip mounting with micron-level precision in high-density mounting scenarios, significantly reducing the risk of chip damage or material rejection due to height deviation.

[0106] 2. This invention possesses excellent resistance to industrial noise interference. By introducing a sliding window mean filtering algorithm, the pressure data queue collected during the recovery process is smoothed. The window size is set to N, and the most recent N consecutive pressure sampling data are taken as the analysis window. The summation is then divided by N to obtain the moving average. Each time a new sampling data is stored, the oldest data in the window is removed, and the new data is added to the end of the window, ensuring the window continuously slides forward and calculates new averages. This "first-in, first-out" sliding average mechanism effectively counteracts various sudden noises such as periodic vibrations from motor operation, airflow disturbances from the pneumatic system, and mechanical shocks from equipment start-up and shutdown. It neutralizes any sudden abnormal high or low values ​​in the pressure data through the averaging effect of other normal data within the window, making the filtered pressure change curve smoother and more stable. Unlike traditional methods that directly use raw pressure data for trigger judgment, which are prone to false triggers or missed triggers due to noise interference at a single moment, this invention significantly improves the reliability and repeatability of critical transition identification through sliding filtering, ensuring that the calibration result of the trigger distance b is not affected by the complex noise environment of the industrial site.

[0107] 3. This invention possesses adaptive compensation capabilities for PCB board warpage. By uniformly selecting four vertices in the mounting area according to set requirements, ensuring that the four vertices are distributed at the four corners of the mounting area and surround the entire mounting position, a laser height measurement module is used to measure the actual height values ​​h1, h2, h3, and h4 at each vertex, and the arithmetic mean c is calculated as the average height parameter of the mounting surface. Unlike traditional methods that rely on the height value of a single measuring point to represent the height of the entire mounting area, a single measuring point cannot reflect the warpage deformation of the PCB board after the reflow soldering process or the local height differences caused by inconsistent support pin heights. The four-point mean fitting method of this invention effectively offsets the extreme deviations caused by local protrusions or depressions through statistical averaging, making the average height c closer to the true overall height level of the mounting area. After substituting it into the height calculation formula, the mounting height can adaptively follow the actual warpage shape of the PCB board, avoiding uneven mounting pressure caused by abnormal local heights.

[0108] 4. This invention constructs a comprehensive correction system integrating multiple error sources. By unifying four parameters—laser reference distance *a*, dynamic touch calibration trigger distance *b*, average mounting surface height *c*, and component thickness *x*—into the height calculation formula *h=a-b+cx*, it achieves a one-time comprehensive correction of multiple error sources, including systematic errors caused by differences in laser installation position, micro-elastic deformation and hysteresis effects caused by nozzle-sensor contact, local height deviations caused by PCB warping and uneven support pins, and differences in component thickness. Unlike traditional methods that only partially compensate for a single error source, resulting in incomplete correction and limited mounting accuracy, this invention's comprehensive correction system organically integrates the error elimination logic of each stage into the same formula framework. This ensures that the final Z-axis landing point command comprehensively covers all key factors affecting mounting height, achieving end-to-end accuracy control from reference establishment to calibration compensation to mounting execution.

[0109] 5. This invention effectively solves the core pain point of placement height control that has long existed in existing technologies. It eliminates height deviation caused by deformation errors through precise trigger distance calibration, compensates for poor adaptability caused by PCB warpage through four-point mean fitting, and solves the problem of accidental triggering due to noise interference through sliding filtering. The synergistic effect of these three technological innovations enables the pick-and-place machine to maintain stable and consistent placement height control performance even under complex industrial conditions. Unlike traditional methods that significantly reduce placement yield in complex scenarios such as high-density placement, thin chips, and large PCBs, this invention significantly improves the placement consistency and operational stability of the pick-and-place machine under various operating conditions. It effectively avoids quality defects such as chip damage, cold solder joints, and component rejection caused by inaccurate placement height, reduces the labor costs of equipment debugging and maintenance, and provides reliable technical support for high-density SMT placement production lines.

[0110] It should be understood that although the steps in the flowcharts of the accompanying figures are shown sequentially as indicated by the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the flowcharts of the accompanying figures may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily completed at the same time, but can be executed at different times, and their execution order is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the sub-steps or stages of other steps.

[0111] The above description is only a partial embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for correcting mounting height, characterized in that, The method includes: The placement head is controlled to move directly above the pressure sensor, the vertical distance from the laser to the surface of the pressure sensor is measured, the nozzle is controlled to descend toward the pressure sensor at a first speed until the pressure value is detected and then the descent stops, and the nozzle is controlled to rise to a set safe distance until the pressure value returns to zero; The nozzle is controlled to descend toward the pressure sensor at a second speed until a pressure value is detected, and then rises back at a third speed. During the rise, the pressure data queue of the pressure sensor within a set time window is collected; the first speed, the second speed, and the third speed decrease sequentially. The pressure data queue is filtered by a sliding window mean filtering algorithm. The critical jump of the pressure value from present to absent in the pressure data queue is monitored in real time. The absolute coordinate distance between the nozzle and the mounting area at the critical jump moment is used as the trigger distance. Four vertices that meet the set requirements are selected in the mounting area. The average height of the vertices is calculated, and the thickness of the mounted component is obtained. The mounting height is calculated based on the vertical distance, trigger distance, average height, and thickness. The landing point command is output based on the mounting height to guide the mounting action.

2. The mounting height correction method as described in claim 1, characterized in that, The control placement head moves directly above the pressure sensor and measures the vertical distance from the laser to the surface of the pressure sensor, including: Control the placement head to move to a position directly above the pressure sensor, ensuring that the laser's emission path is perpendicular to the surface of the pressure sensor, and start the laser to emit a laser beam onto the surface of the pressure sensor; After receiving the reflected signal, the vertical distance between the laser's output port and the upper surface of the pressure sensor is calculated; the vertical distance is used to eliminate system errors caused by differences in the laser's installation position.

3. The mounting height correction method as described in claim 1, characterized in that, The control nozzle descends toward the pressure sensor at a first speed until it detects a pressure value, then stops descending. Controlling the nozzle to rise a set safe distance until the pressure value returns to zero includes: The nozzle is controlled to descend rapidly toward the surface of the pressure sensor at a first speed. The descent is stopped immediately when the nozzle touches the pressure sensor and detects the pressure value increasing from zero. The nozzle is controlled to rise upwards by a preset safety distance; the safety distance is used to ensure that the nozzle is completely removed from the surface of the pressure sensor and that the reading of the pressure sensor is returned to zero.

4. The mounting height correction method as described in claim 1, characterized in that, The process involves controlling the nozzle to descend towards the pressure sensor at a second speed until a pressure value is detected, and then to rise again at a third speed. During the rise, pressure data from the pressure sensor within a set time window is collected, including: The nozzle is controlled to slowly descend toward the surface of the pressure sensor at a second speed, and the descent stops when the nozzle head touches the pressure sensor again and detects the pressure value from zero to one. The suction nozzle is controlled to rise upward at a third speed. During the rise, the suction nozzle is moved step by step in a set increment. Each step is used to simultaneously collect the current reading of the pressure sensor and store the collected pressure data into the pressure data queue within a set time window.

5. The mounting height correction method as described in claim 1, characterized in that, The step of filtering the pressure data queue using a sliding window mean filtering algorithm includes: Set the window size to N, take the N most recent consecutive pressure sampling data in the pressure data queue as the analysis window, sum the N data in the analysis window and divide by N to obtain the moving average at the current time; When new sampled data is stored, the oldest data in the analysis window is removed, and the new sampled data is added to the end of the window, so that the analysis window keeps sliding forward and continuously calculating new moving averages.

6. The mounting height correction method as described in claim 1, characterized in that, The real-time monitoring of the critical transition of pressure values ​​from present to absent in the pressure data queue, using the absolute coordinate distance from the nozzle to the mounting area at the critical transition moment as the trigger distance, includes: During the process of the suction nozzle rising at the third speed and continuously collecting filtered pressure data, the moment when the filtered pressure value in the pressure data queue suddenly changes from a positive value greater than zero to zero is monitored in real time, and the absolute coordinate distance between the suction nozzle and the mounting area corresponding to the instant is used as the trigger distance.

7. The mounting height correction method as described in claim 1, characterized in that, The process involves selecting four vertices that meet set requirements in the mounting area, calculating the average height of the vertices, obtaining the thickness of the mounted component, calculating the mounting height based on the vertical distance, trigger distance, average height, and thickness, and outputting a landing point command based on the mounting height to guide the mounting action, including: Four vertices are selected in the mounting area according to the set requirements; the four vertices must be evenly distributed at the four corners of the mounting area and surround the entire mounting area. The actual height value at each vertex is measured using a laser, and the arithmetic mean is calculated as the average height of the mounting surface to obtain the thickness of the current mounting component. The mounting height is obtained by subtracting the trigger distance from the vertical distance, adding the average height from the thickness, and outputting the Z-axis landing point command based on the mounting height to guide the nozzle to complete the mounting action.

8. A mounting height correction device, characterized in that, The device includes: The reference acquisition and deformation elimination module is used to control the placement head to move directly above the pressure sensor, measure the vertical distance from the laser to the surface of the pressure sensor, control the nozzle to descend toward the pressure sensor at a first speed until the pressure value is detected and then stop descending, and control the nozzle to rise to a set safe distance until the pressure value returns to zero. The dynamic bottoming and critical calibration module is used to control the nozzle to descend toward the pressure sensor at a second speed until the pressure value is detected, and then rise back at a third speed. During the rise, the pressure data queue of the pressure sensor within a set time window is collected; the first speed, the second speed and the third speed decrease sequentially. The mounting surface mean fitting module is used to filter the pressure data queue using a sliding window mean filtering algorithm, monitor the critical jump of the pressure value from present to absent in the pressure data queue in real time, and use the absolute coordinate distance between the nozzle and the mounting area at the critical jump moment as the trigger distance. The height calculation and compensation module is used to select four vertices that meet the set requirements in the mounting area, calculate the average height of the vertices, obtain the thickness of the mounted element, calculate the mounting height based on the vertical distance, trigger distance, average height and thickness, and output a landing point command based on the mounting height to guide the mounting action.

9. An electronic device, characterized in that, include: At least one processor and at least one memory, wherein, The memory stores computer-readable instructions; The computer-readable instructions are executed by one or more of the processors, causing the electronic device to implement the mounting height correction method as described in any one of claims 1 to 7.

10. A storage medium having computer-readable instructions stored thereon, characterized in that, The computer-readable instructions are executed by one or more processors to implement the mounting height correction method as described in any one of claims 1 to 7.

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