A high-synchronization tracking method and device for power battery flight welding

Abstract

The application discloses a height synchronization tracking method and device for power battery flight welding, and relates to the technical field of flight welding control, which comprises the following steps: obtaining the height measurement value of the current welding area as the height reference data of the current welding point in the inter-welding-point gap of laser welding; determining the height adjustment amount of the current welding point relative to the reference position of the welding sequence based on the height reference data, updating the height adjustment amount based on the height adjustment amount adopted by the previous welding point, and generating the laser focal point position parameter corresponding to the current welding point; and setting and keeping the laser focal point position unchanged according to the laser focal point position parameter during the duration of laser emission and current welding. The application distinguishes the height measurement from the welding execution in time, so that the height reference data is obtained only in the inter-welding-point gap, and the laser focal point position is kept unchanged during the welding duration.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of flight welding control, in particular to a height synchronization tracking method and device for power battery flight welding. BACKGROUND

[0002] With the wide application of power batteries in the field of new energy vehicles and energy storage, higher requirements are put forward for the welding quality of battery pole pieces, busbars and connecting pieces. Laser flight welding has been widely used in the batch manufacturing process of power batteries due to its advantages of fast processing speed, concentrated heat input and easy automation integration. In this type of welding process, the laser beam moves at high speed between multiple welding points and completes welding one by one. The control accuracy of the laser focal point position directly affects the consistency of the weld penetration and the welding reliability.

[0003] In the existing power battery flight welding system, the laser focal point position is usually controlled by height synchronization tracking, that is, the laser focal point position is compensated in real time according to the height change of the workpiece surface during welding. Related technologies often use height measurement results obtained before welding or during the welding process as control basis in order to keep the laser focal point at the expected process position at all times. However, during actual laser welding, phenomena such as molten pool, vapor and plasma may occur in the welding area, which may interfere with the height measurement signal, making it difficult to accurately reflect the true workpiece geometry.

[0004] In the flight welding scene, the switching frequency between welding points is high and the control period is short. If the synchronization compensation is continuously based on the height measurement signal affected by welding during the welding process, the laser focal point position may change frequently between adjacent welding points, and the deposition process of laser energy is difficult to respond synchronously, thereby introducing weld penetration fluctuations in the welding sequence, and even causing local weld-through or incomplete penetration. Therefore, how to reasonably obtain height reference data and stably control the laser focal point position without affecting the welding beat has become a technical problem that needs to be solved in the field of power battery flight welding. Therefore, the present application provides a height synchronization tracking method and device for power battery flight welding. SUMMARY

[0005] The present application aims to provide a height synchronization tracking method and device for power battery flight welding to solve the problems mentioned in the background.

[0006] The present application can be implemented by the following technical scheme: a height synchronization tracking method for power battery flight welding, comprising:

[0007] Step one, in the gap between the laser welding points, obtain the height measurement value of the current to-be-welded area as the height reference data of the current welding point.

[0008] The inter-spot gap is a time interval between adjacent welding spots, from the end of welding of a previous welding spot to the start of welding of a next welding spot;

[0009] Step two, based on the height reference data, determine the height adjustment amount of the current welding spot relative to the reference position of the welding sequence, and update the height adjustment amount based on the height adjustment amount adopted by the previous welding spot, to generate the laser focal point position parameter corresponding to the current welding spot;

[0010] Step three, during the duration of laser emission and current welding spot welding, the laser focal point position is set and kept unchanged according to the laser focal point position parameter, and the laser focal point position is not adjusted based on the real-time height measurement value during the duration;

[0011] Step four, after completing the welding of the current welding spot, the height measurement value of the region corresponding to the next welding spot is obtained as the height reference data of the next welding spot;

[0012] Step five, when welding a plurality of welding spots in succession, the change of the height adjustment amount between adjacent welding spots is constrained, so that the laser focal point positions corresponding to the adjacent welding spots change continuously and gently along the welding sequence.

[0013] Further technical improvements of the present application are that step one includes:

[0014] According to the current welding process parameters and the workpiece material properties, the heat input of the previous welding spot is calculated by heat diffusion to determine the predicted range of the heat affected zone generated by the previous welding spot;

[0015] The region located outside the predicted range of the heat affected zone and in front of the current welding spot along the welding direction is defined as a candidate measurement region;

[0016] The candidate measurement region is quickly optically imaged to obtain corresponding surface image information, and based on abnormal situations of reflection characteristics, texture continuity or brightness distribution in the surface image information, a sub-region with abnormal surface features is marked;

[0017] In the effective region after excluding the abnormal surface feature sub-region, at least two measurement positions are selected along the welding direction, and at least one of the measurement positions is located on the extended line of the predicted welding spot track;

[0018] In the inter-spot gap, corresponding height measurement values are obtained at the at least two measurement positions to form multiple height measurement values of the current welding spot;

[0019] The multiple height measurement values are respectively compared with average height values of the multiple height measurement values, and height measurement values with a deviation exceeding a preset height deviation threshold are removed; the remaining height measurement values after removal are averaged to obtain a single height measurement value, and the single height measurement value is taken as the height reference data of the current welding point.

[0020] Further technical improvements of the present application are that the step of heat diffusion calculation comprises:

[0021] The laser power parameter and the welding speed parameter corresponding to the previous welding point are obtained, and the unit length heat input value corresponding to the previous welding point in the welding process is calculated according to the laser power parameter and the welding speed parameter;

[0022] The thermal conductivity parameter, the specific heat parameter and the density parameter of the workpiece material are obtained, and the diffusion distances of heat along the welding sequence direction and perpendicular to the welding sequence direction are respectively calculated based on the unit length heat input value, the thermal conductivity parameter, the specific heat parameter and the density parameter;

[0023] The time point at which the previous welding point completes welding and the time point at which the current welding point starts height measurement are obtained, and the time interval between the two time points is calculated;

[0024] According to the time interval, the diffusion distances along the welding sequence direction and perpendicular to the welding sequence direction are corrected;

[0025] According to the diffusion distances after correction, the space section covered by the heat diffusion of the previous welding point in the welding sequence direction and the transverse direction thereof is determined, and the space section is taken as the heat affected zone prediction range corresponding to the previous welding point.

[0026] Further technical improvements of the present application are that the step of generating the laser focal point position parameter corresponding to the current welding point based on the height reference data comprises:

[0027] Based on the preset connection relationship of the adjacent welding points in the welding sequence, the welding path segment to which the current welding point belongs is determined, and it is judged whether the current welding point is a starting welding point of the welding path segment or a welding point at which the path direction changes;

[0028] When it is judged that the current welding point is the starting welding point of the welding path segment or the welding point at which the path direction changes, the height adjustment amount of the current welding point is determined based on the height reference data of the current welding point and the height value corresponding to the welding sequence reference position, and the height adjustment amount is taken as the height adjustment amount used for updating of the current welding point;

[0029] When it is judged that the current welding point is not the starting welding point of the welding path segment and the path direction has not changed, based on the height reference data of the current welding point and the height reference data of the previous welding point, the relative height change between the adjacent welding points is determined, and the height adjustment amount for updating of the current welding point is determined based on the height adjustment amount adopted by the previous welding point and in combination with the relative height change;

[0030] The height adjustment amount is updated based on the height adjustment amount for updating on the basis of the height adjustment amount adopted by the previous welding point, and the laser focal point position parameter corresponding to the current welding point is generated.

[0031] A further technical improvement of the application is that step three includes steps performed at the start time of the duration during which the laser is emitted and the current welding point is welded, and steps performed at the end time of the duration:

[0032] At the start time of the duration, the laser focal point position parameter corresponding to the current welding point is written into the laser focal point position parameter latch area and latched;

[0033] During the latch holding period, the laser focal point position is set according to the laser focal point position parameter in the laser focal point position parameter latch area, and rewriting of the laser focal point position parameter in the laser focal point position parameter latch area is prohibited;

[0034] During the latch holding period, the sampling trigger signal of the height measurement channel is subjected to gate processing, so that the height measurement channel does not output real-time height measurement values for updating of the laser focal point position;

[0035] At the end time of the duration, the latch is released and the gate processing is released, and the laser focal point position parameter corresponding to the next welding point is written and latched.

[0036] A further technical improvement of the application is that step four includes the following steps when the height reference data of the next welding point is acquired after the welding of the current welding point is completed:

[0037] During the welding of the current welding point, the height measurement position corresponding to the next welding point is determined in advance;

[0038] At the time when the laser is switched from the emitted state to the non-emitted state, height measurement at the height measurement position is triggered;

[0039] At least two height measurement values are continuously acquired at the height measurement position within the same welding point gap;

[0040] The at least two height measurement values are subjected to consistency comparison processing, and a single height measurement value is selected;

[0041] The single height measurement value is recorded as the height reference data of the next welding point.

[0042] The further technical improvement of the present application is that step five includes the following steps when continuously welding multiple welding points:

[0043] A1, based on the spatial coordinate relationship between adjacent welding points in the welding path data, when the welding path direction of adjacent welding points remains continuous and no direction change occurs, the adjacent welding points are determined to belong to the same continuous welding path segment;

[0044] When the welding path direction changes, the welding sequence is divided into different continuous welding path segments;

[0045] A2, within the same continuous welding path segment, according to the execution order of the welding points in the welding sequence, read the height adjustment amount adopted when the previous welding point is welded as the segment reference height adjustment amount corresponding to the current welding point;

[0046] A3, subtract the height adjustment amount determined by step two from the segment reference height adjustment amount to obtain the height adjustment amount change value corresponding to the current welding point;

[0047] A4, compare the height adjustment amount change value with the change limit value stored in the parameter area corresponding to the continuous welding path segment;

[0048] When the absolute value of the height adjustment amount change value is greater than the change limit value, generate a replacement height adjustment amount based on the segment reference height adjustment amount and superimposed with the change limit value;

[0049] When the absolute value of the height adjustment amount change value is not greater than the change limit value, the height adjustment amount determined by step two is adopted;

[0050] A5, the final height adjustment amount of the current welding point is used to generate the corresponding laser focal point position parameters, and the height adjustment amount determination process of the next welding point is entered.

[0051] The further technical improvement of the present application is that in the process of obtaining height reference data based on step one and executing step two to generate height adjustment amount, when the height mutation feature of the workpiece surface is identified on the welding path in front of the current welding point, the following steps are further included:

[0052] Based on the surface image information obtained in step one, analyze the welding area located within a predetermined distance range in front of the current welding point in the welding path direction, identify the area with continuous edge change or light-dark boundary feature, and determine the corresponding continuous multiple welding points as the height mutation transition zone;

[0053] For the height mutation transition zone, the estimated height reference data corresponding to each welding spot in the height mutation transition zone is obtained, and combined with the laser focal point position parameter currently adopted by the welding spot, the laser focal point position corresponding to each welding spot in the height mutation transition zone is calculated according to the welding execution sequence, and the planning laser focal point position parameter corresponding to each welding spot in the height mutation transition zone is generated one by one;

[0054] Based on the numerical relationship between the planning laser focal point position parameter and the height value corresponding to the welding sequence reference position, the planning height adjustment amount corresponding to each welding spot in the height mutation transition zone is calculated, and the planning height adjustment amount is associated and stored with the corresponding welding spot;

[0055] When performing welding of the welding spot in the height mutation transition zone, the height adjustment amount of the corresponding welding spot in step two is updated, and the planning height adjustment amount associated with the welding spot is directly used to generate the laser focal point position parameter of the corresponding welding spot;

[0056] After the welding of the welding spot in the height mutation transition zone is completed, for the subsequent welding spot, the height adjustment amount of the corresponding welding spot is determined again based on the height reference data of the corresponding welding spot in step two, and the constraint processing of the change of the height adjustment amount between adjacent welding spots in step five is continued.

[0057] On the other hand, the application also discloses a height synchronous tracking device for power battery flight welding, which adopts any one of the height synchronous tracking methods in the above scheme.

[0058] Compared with the prior art, the application has the following beneficial effects:

[0059] The application distinguishes the height measurement and the welding execution in time, so that the height reference data is only obtained in the welding spot gap, and the laser focal point position does not change during the welding duration, thereby avoiding the interference of the molten pool, vapor and plasma on the height measurement signal during the welding process, and ensuring that the height data used for control has high reliability;

[0060] Moreover, by introducing the update and constraint mechanism of the height adjustment amount between adjacent welding spots, the application effectively limits the mutation of the laser focal point position in the welding sequence while maintaining the height change response capability between welding spots, so that the laser focal point position can change continuously along the welding path from welding spot to welding spot, which is beneficial to the stable deposition of laser energy between multiple welding spots and improves the consistency of welding penetration and the overall welding quality;

[0061] In another aspect, the present application combines the welding path characteristics and the workpiece surface state, and in specific cases, the generation and adoption of the height adjustment amount are processed in a targeted manner, so that the height synchronous tracking method can better adapt to the application scenarios of high speed, multiple welding points and complex workpiece surfaces in the power battery flight welding. Without changing the basic structure of the existing welding system, the stability and applicability of the height synchronous control are improved. BRIEF DESCRIPTION OF DRAWINGS

[0062] In order to facilitate the understanding of those skilled in the art, the present application will be further described below with reference to the accompanying drawings.

[0063] Figure 1 The method logic diagram of the present application. DETAILED DESCRIPTION

[0064] In order to further illustrate the technical means and effects adopted by the present application to achieve the predetermined application purpose, the specific embodiments, structures, features and effects according to the present application are described in detail below with reference to the accompanying drawings and preferred embodiments. EMBODIMENT

[0065] Please refer to Figure 1 As shown in the figure, the present application provides a height synchronous tracking method for power battery flight welding, which comprises:

[0066] Step one, in the inter-weld gap of laser welding, the height measurement value of the current to-be-welded area is obtained as the height reference data of the current welding point;

[0067] The inter-weld gap is the time interval between the adjacent welding points, from the end time of the welding of the previous welding point to the start time of the welding of the next welding point; the height measurement action in this step is limited to be completed within the time interval when the laser does not apply welding energy to the workpiece, so that the obtained height measurement value is not affected by the molten pool, vapor or plasma phenomena in the welding process, thereby obtaining height reference data that can truly reflect the geometric state of the to-be-welded area, and providing a reliable data basis for the subsequent laser focal point position calculation.

[0068] Specifically, after the previous welding point before the current welding point is completed, the current welding process parameters and workpiece material properties are obtained, and the heat diffusion calculation of the heat input of the previous welding point is performed to determine the predicted range of the heat affected zone generated by the previous welding point. Among them, the laser power parameter and the welding speed parameter corresponding to the previous welding point are obtained, for example, the laser power parameter is 1200W, and the welding speed parameter is 1.2m / s, and the corresponding unit length heat input value of the previous welding point in the welding process is calculated according to the laser power parameter and the welding speed parameter. The unit length heat input value is obtained by dividing the laser power parameter by the welding speed parameter, which corresponds to 1000J / m.

[0069] Meanwhile, the thermal conductivity parameter, the specific heat parameter and the density parameter of the workpiece material are obtained;

[0070] For example, the thermal conductivity parameter is 160 W / (m·K), the specific heat parameter is 900 J / (kg·K), and the density parameter is 2700 kg / m³. The thermal diffusion capacity characteristic value of the workpiece material is calculated based on the thermal conductivity parameter, the specific heat parameter and the density parameter. The thermal diffusion capacity characteristic value is the thermal diffusion rate of the material, which is obtained by dividing the thermal conductivity parameter by the product of the density parameter and the specific heat parameter. Then, the unit length heat input value and the thermal diffusion capacity characteristic value are combined to obtain the basic diffusion distance of heat along the welding sequence direction and perpendicular to the welding sequence direction according to a preset conversion relationship. The basic diffusion distance along the welding sequence direction can be taken as 1.0 mm, and the basic diffusion distance perpendicular to the welding sequence direction can be taken as 0.7 mm.

[0071] The time point at which the previous welding point completes welding and the time point at which the current welding point starts height measurement are obtained, and the time interval between the two time points is calculated. For example, the time interval between the time point at which the previous welding point completes welding and the time point at which the current welding point starts height measurement is 4 ms. Then, the step of "correcting the diffusion distance along the welding sequence direction and the diffusion distance perpendicular to the welding sequence direction according to the time interval" is performed. The time correction reference interval is taken as 1 ms, the time interval and the time correction reference interval are subjected to ratio operation, and then square root operation is performed to obtain the time correction factor. In the above example, the time correction factor is the result of square root operation of the ratio of the time interval 4 ms to the time correction reference interval 1 ms, which corresponds to 2.0. The basic diffusion distance along the welding sequence direction and the basic diffusion distance perpendicular to the welding sequence direction are multiplied by the time correction factor respectively to obtain the corrected diffusion distance. The corrected diffusion distance along the welding sequence direction is 2.0 mm, and the corrected diffusion distance perpendicular to the welding sequence direction is 1.4 mm. According to the corrected diffusion distance, the space section covered by the heat diffusion of the previous welding point in the welding sequence direction and the transverse direction thereof is determined, and the space section is taken as the heat affected zone prediction range corresponding to the previous welding point.

[0072] After determining the heat-affected zone prediction range corresponding to the previous welding point, the area located outside the heat-affected zone prediction range and in front of the current welding point in the welding direction is defined as a candidate measurement area. For example, the candidate measurement area is formed by extending 3 mm forward of the current welding point in the welding sequence direction and maintaining a safety interval of no less than 0.5 mm in the transverse direction. Then, the candidate measurement area is subjected to rapid optical imaging to obtain corresponding surface image information, such as a surface grayscale image at a collection rate of no less than 20000 frames / s; and based on abnormal situations of reflection characteristics, texture continuity or brightness distribution in the surface image information, a sub-area with abnormal surface features is marked. The candidate measurement area can be divided into a plurality of pixel blocks, and when the difference between the average grayscale value of a pixel block and the average grayscale value of its adjacent pixel blocks exceeds 30, or the grayscale variance within the pixel block exceeds 200, or the continuous edge segment obtained by edge detection appears more than 5 pixel breaks, the area covered by the corresponding pixel block is marked as a sub-area with abnormal surface features.

[0073] In the effective area after excluding the sub-area with abnormal surface features, at least two measurement positions are selected in the welding direction, and at least one of the measurement positions is located on the extension line of the predicted welding point trajectory. For example, a first measurement position is selected on the extension line of the welding trajectory, and a second measurement position is selected 2 mm in front of the first measurement position. In the inter-weld gap, height measurement values are obtained at the at least two measurement positions, respectively. For example, the height measurement value obtained at the first measurement position is 0.85 mm, and the height measurement value obtained at the second measurement position is 0.88 mm, thereby forming multiple height measurement values of the current welding point, providing reliable input for subsequent determination of the height reference data of the current welding point.

[0074] The multiple height measurement values are compared with the average height value of the multiple height measurement values, respectively, and the height measurement values with a deviation exceeding a preset height deviation threshold are removed. The remaining height measurement values after removal are averaged to obtain a single height measurement value, and the single height measurement value is taken as the height reference data of the current welding point.

[0075] Step two, based on the height reference data, determine the height adjustment amount of the current welding point relative to the welding sequence reference position, and update the height adjustment amount based on the height adjustment amount adopted by the previous welding point to generate the laser focal point position parameter corresponding to the current welding point; this step converts the height reference data of discrete welding points into height adjustment amount for controlling the position of the laser focal point, and updates the height adjustment amount based on the height adjustment amount adopted by the previous welding point, so that the change of the laser focal point position has continuity, avoiding the introduction of abrupt focal point jumps due to the change of the height of a single welding point, thereby providing a continuous parameter source for the stable control of the focal point position in the flight welding process.

[0076] Specifically, in one specific embodiment of the present application, when generating the laser focal point position parameter corresponding to the welding spot based on the acquired current welding spot height reference data in step two, the following detailed step sequence is executed to realize adaptive matching and serialized updating of the height adjustment amount and the welding path geometry characteristics.

[0077] The identification of the welding path segment and the judgment of the welding spot attribute are performed in the following specific process: the welding path segment to which the current welding spot belongs is determined according to the spatial connection coordinates between adjacent welding spots in the welding sequence, which are pre-set and stored in the control system. The welding path segment refers to a segment of the welding trajectory formed by multiple welding spots, the welding movement direction of which remains continuous. The determination logic includes: analyzing the direction of the line connecting the current welding spot and the previous welding spot, if the direction is consistent with the pre-set path segment direction, it is determined that the current welding spot is located in the continuous welding path segment; if there is no welded welding spot before the current welding spot, or the change angle of the line connecting the current welding spot and the previous welding spot with respect to the pre-set path segment direction exceeds a pre-set threshold (for example, 15 degrees), it is determined that the current welding spot is the starting welding spot of a new welding path segment or the welding spot where the path direction changes. Through this step, clear logical input is provided for the subsequent selection of height adjustment amount calculation strategy.

[0078] Secondly, according to the judgment result of the welding spot attribute, two different height adjustment amount calculation strategies are respectively executed.

[0079] When the judgment result is that the current welding spot is the starting welding spot of the welding path segment or the welding spot where the path direction changes, the first strategy, i.e. the absolute reference calculation method, is adopted. The specific sub-steps of this method are: reading the current welding spot height reference data obtained through the aforementioned step one, for example, a measurement value of 0.85 mm; at the same time, calling the pre-stored reference position height value associated with the entire welding sequence, which usually represents the theoretical design plane or the initial calibration plane of the workpiece, for example, the value is set to 0.00 mm. Then, the current welding spot height reference data is subtracted from the height value corresponding to the welding sequence reference position, and the difference obtained is the height deviation of the current welding spot with respect to the absolute reference system. This deviation value is directly determined as the height adjustment amount used for updating the current welding spot. For example, +0.85 mm is calculated.

[0080] When the result of the judgment is that the current welding point is not the starting point of the welding path segment and the path direction has not changed, a second strategy, i.e., a "relative tracking calculation method", is adopted. The specific sub-steps of this method are as follows: the height reference data of the current welding point (for example, the latest measured value is 0.88 mm) and the height reference data of the immediately preceding welding point (for example, the recorded value is 0.85 mm) are read at the same time. The arithmetic difference between the two is calculated to obtain the relative height change value representing the local height change, which is +0.03 mm in this example. Then, the height adjustment value actually adopted and recorded when the preceding welding point is welded is obtained from the system memory, for example, the value is +0.85 mm. Finally, the calculated relative height change value (+0.03 mm) and the height adjustment value adopted by the previous welding point (+0.85 mm) are algebraically added, and the result (+0.88 mm) is determined as the height adjustment value for updating the current welding point.

[0081] Finally, the updating of the height adjustment value and the generation of the laser focal point position parameter are performed; after the height adjustment value for updating the current welding point is determined, an updating operation is performed to output the final executed parameter. In this embodiment, the updating operation is defined as direct assignment, i.e., the height adjustment value for updating the current welding point is directly used as the final height adjustment value adopted by the current welding point. Subsequently, based on the final height adjustment value, the accurate position instruction required to drive the laser focal point positioning actuator (such as a servo motor or a piezoelectric ceramic) is calculated through the coordinate transformation module, and the instruction is the laser focal point position parameter corresponding to the current welding point. For example, the finally generated position parameter instruction corresponds to controlling the focal point to be positioned in the vertical direction at a spatial coordinate that is upwardly offset from the theoretical zero point by 0.88 mm. This parameter is transmitted to the subsequent focal point position latching and execution control link to complete the closed-loop decision from the height information to the focal point execution position.

[0082] Step three, during the duration of laser emission and welding of the current welding point, the laser focal point position is set and kept unchanged according to the laser focal point position parameter, and the laser focal point position is not adjusted based on the real-time height measurement value during the duration; this step fixes the use of the pre-determined laser focal point position parameter to complete the welding operation when the laser welds the current welding point, avoiding frequent adjustment of the laser focal point position due to fluctuations in the height measurement signal during the action of the welding energy, thereby ensuring stable deposition of the laser energy during the welding process.

[0083] Specifically, in one specific embodiment of the present application, step three includes steps performed at the start time of the duration and steps performed at the end time of the duration during the duration of laser emission and welding of the current welding point.

[0084] Step three, when the laser is switched from non-firing state to firing state and enters the current welding spot welding, is executed according to the following detailed steps to build an absolutely stable and anti-interference focus position execution environment during the welding duration.

[0085] At the precise moment when the laser receives the control instruction and is switched from non-firing state to firing state, i.e. at the start of the duration, the final writing of the focus position parameter and the hardware latching action are triggered. Specifically, in the same control cycle when the laser firing enable signal rises, the laser focus position parameter corresponding to the current welding spot (for example, a digital quantity representing the target position of the Z-axis as +0.88 mm) calculated and generated by the foregoing steps is written to a physical memory area dedicated for this purpose, i.e. the laser focus position parameter latching area, through the data bus. At the same time when the writing operation is completed, the storage area is locked by an independent hardware latching signal, and this action is called "complete latching". Once the latching is completed, the data in the storage area is physically isolated from the external data bus and enters a protected read-only state. This step ensures that at the critical point when the welding starts, the execution parameter is frozen instantaneously, and any subsequent variable fluctuations at the software level cannot affect this determined parameter.

[0086] During the entire duration when the laser is in the firing state and is performing the current welding spot welding, i.e. during the latching holding period, the setting and maintenance of the laser focus position completely depend on the parameter in the aforementioned latching area, and any rewriting attempt is strictly prohibited. During this period, the motion controller responsible for controlling the laser focus position (for example, the controller controlling the Z-axis servo motor) has its position loop set value input port configured to continuously read the fixed parameter value in the laser focus position parameter latching area (for example, continuously +0.88 mm). The motion controller drives the actuator according to this fixed set value to stabilize the laser focus at the target position. At the same time, the software permission management module or the hardware write enable circuit of the control system is activated, which functions to prohibit any form of data writing request to the laser focus position parameter latching area. Whether it is due to regular control cycle refresh or data rewriting triggered by abnormal interruption, it is blocked by this mechanism, thereby ensuring the absolute stability of the parameter during the welding process at both logical and physical levels.

[0087] Likewise, during the above-mentioned latch holding period, active signal isolation, i.e. gating process, is implemented for the height measurement channel that is likely to be disturbed. In practice, during the period when the laser emission enable signal is active, a hardware gating circuit directly controlled by the signal or a software flag synchronized therewith is set. The gating signal acts on the sampling trigger input of the height measurement sensor (e.g. laser triangulation sensor) or on the transmission path of the sensor data to the controller. The effect is that, during the welding duration, the height measurement channel is prohibited from initiating a new sampling trigger or discarding / shielding any real-time height measurement value data packet that has been sampled by the channel, so that it cannot enter the subsequent data processing and decision loop. Therefore, no matter what kind of disturbance the plasma, spatter or strong light radiation generated by welding causes to the height measurement, these contaminated real-time height measurement values are prevented from being used for the update calculation of the laser focal point position, thus fundamentally cutting off the propagation path of the interference signal.

[0088] At the time when the current welding spot is welded and the laser is switched back from the emission state to the non-emission state, i.e. at the end of the duration, the forced constraints on the focal point position parameter and the height measurement channel are simultaneously released, preparing for the next welding period. Specifically, when the falling edge of the laser emission enable signal arrives, the hardware latch signal is cancelled and the laser focal point position parameter latch area returns to the writable state. At the same time, the gating signal acting on the sampling trigger of the height measurement channel is released and the channel returns to normal sampling and data transmission function. The control system then exits the "welding execution state" of the current welding spot and automatically enters the preparation process of the laser focal point position parameter calculation, writing and latching corresponding to the next welding spot according to the progress of the welding sequence, thus forming a reliable control cycle that is repeated and each state is strictly separated.

[0089] Step four, after the welding of the current welding spot is completed, the height measurement value of the region corresponding to the next welding spot is obtained as the height reference data of the next welding spot; this step re-enters the height measurement state after the welding of the current welding spot is completed and the action of laser energy is ended, and the height of the region corresponding to the next welding spot is measured, so that the update of height synchronous tracking only occurs in the welding spot switching stage, thereby forming a control rhythm of "inter-welding spot update and intra-welding spot maintenance" in the entire welding sequence.

[0090] Specifically, in one specific embodiment of the present application, when the height reference data of the next welding spot is obtained after the welding of the current welding spot is completed in step four, the following detailed steps are executed in sequence to realize the foresight, rapidity and high reliability of inter-welding spot height measurement.

[0091] During the current welding spot, the pre-calculation and determination of the next welding spot height measurement position is performed synchronously. Specifically, based on the welding sequence path data stored in the controller, combined with the spatial coordinates of the current welding spot and the welding motion direction vector, the theoretical spatial coordinates of the next welding spot in front are pre-calculated by geometric offset calculation. Then, based on the theoretical coordinates, combined with the predetermined measurement position offset rule (for example, 2.0 millimeters in front along the welding motion direction), the precise three-dimensional coordinates for height measurement are calculated, which are determined as the height measurement position of the next welding spot corresponding area. For example, the calculated coordinates of the height measurement position in the workpiece coordinate system are (X=10.2mm, Y=5.0mm, Z to be measured). The coordinate values are temporarily stored in a dedicated measurement preparation buffer. This step completes the time-consuming position calculation work in the relatively generous welding time from the valuable and short inter-spot gap, which wins a critical time window for subsequent real-time measurement.

[0092] At the precise moment when the current welding spot is completed and the laser is switched from the emission state to the non-emission state, the height measurement action at the pre-determined height measurement position is triggered immediately. Specifically, the falling edge of the laser off signal is used as a hardware trigger event. The trigger signal directly starts the measurement sequence of the height measurement sensor (such as a laser triangulation sensor): first, the actuator (such as a galvanometer) that controls the deflection of the light beam receives and executes the instruction to quickly position the measurement light beam to the height measurement position (coordinates (10.2mm, 5.0mm)); then, after the light beam is stabilized, the light-emitting unit inside the sensor is triggered to emit measurement laser, and the optical receiving unit and the analog-to-digital converter are simultaneously started to begin collecting height raw signals for the position. This "event-triggered" mode ensures that the height measurement is started at the moment when the inter-spot gap begins, maximizing the use of limited gap time.

[0093] In the same inter-spot gap after triggering the height measurement, continuous multiple rapid samplings are performed on the height measurement position to obtain at least two height measurement values. Since the sensor and the controller are in place, within a very short period of time (for example, within 1 millisecond), the control sequence commands the sensor to perform continuous multiple independent samplings at a high repetition frequency (for example, 10 kilohertz). Each sampling completes the whole process from light signal emission, echo reception, to digital quantity conversion, thereby outputting an independent height measurement raw value. For example, within this inter-spot gap, three height measurement raw values may be obtained in turn: 0.862 millimeters, 0.859 millimeters, 2.105 millimeters (this value may be abnormal due to instantaneous spatter interference). These values are recorded in order to form a set of multiple height measurement values for the same measurement position.

[0094] The consistency comparison and data processing are performed on the obtained at least two height measurement values, and a single height measurement value that best represents the true height is selected. The specific processing sub-steps include: first, calculating the statistical characteristics of the plurality of height measurement values, such as the arithmetic mean and the standard deviation. Next, consistency verification is performed, for example, obvious outliers deviating from the mean value by more than a preset threshold (such as ±0.05 mm) are removed (in the above example, 2.105 mm is removed due to excessive deviation). Then, the average value of the remaining valid measurement values (0.862 mm, 0.859 mm) is calculated again. Finally, the average value (for example, 0.8605 mm, rounded to 0.860 mm) is selected as the single height measurement value representing the true geometric state of the height measurement position. This process effectively suppresses random noise or transient interference that may be encountered in single sampling.

[0095] The single height measurement value selected by the consistency comparison process is formally recorded and stored as the height reference data of the next welding point. The recording operation binds the value (0.860 mm) with the unique identifier of the next welding point (such as the welding point serial number) and writes it into the height reference database that provides input data for step two. In this way, a high-reliability height reference data obtained through the "pre-positioning, immediate triggering, multiple sampling, intelligent screening" process is ready for the focal position parameter calculation step in the next welding cycle, thereby closing the efficient data flow from the end of welding to the preparation of decision basis for the next welding point.

[0096] Step five, when continuously welding a plurality of welding points, the change of the height adjustment amount between adjacent welding points is constrained, so that the laser focal position corresponding to the adjacent welding points changes continuously and smoothly along the welding sequence; in the case of continuous welding of a plurality of welding points, the change amplitude of the height adjustment amount between adjacent welding points is controlled, so that the laser focal position is adjusted in a continuous and gradual manner along the welding sequence, avoiding sudden changes in the focal position due to excessive changes in the height adjustment amount, thereby improving the overall welding stability during flight welding;

[0097] Specifically, in one specific embodiment of the present application, step five, when continuously welding a plurality of welding points, is executed according to the following detailed step sequence to realize intelligent constraint and sequence smoothing of the height adjustment amount between welding points, and to ensure continuous and stable transition of the laser focal position.

[0098] Based on the stored welding path data, the welding sequence is geometrically segmented to identify and divide different continuous welding path segments. In practice, the spatial coordinates of adjacent welding points in the welding sequence are analyzed in sequence, and the direction vector of the line connecting each pair of adjacent welding points is calculated. By comparing the included angle between the direction vector of the line connecting the current welding point and the previous welding point and the direction vector of the line connecting the previous welding point and its previous sequence welding point, it is determined whether the welding path direction is continuous. When the included angle is less than a predetermined continuity angle threshold (for example, less than 5 degrees), it is determined that the welding path direction remains continuous and no direction change occurs, and the current welding point and the previous welding point are classified into the same continuous welding path segment. Conversely, when the included angle is greater than or equal to the threshold (for example, a 90-degree corner is detected), it is determined that the welding path direction changes, and the welding sequence is divided into a new starting point of a continuous welding path segment at this point. For example, a welding sequence containing twenty welding points may form a straight line path (continuous path segment A) with the first ten welding points, and form another straight or curved path with different directions (continuous path segment B) with the last ten welding points.

[0099] Secondly, after completing the path segmentation, a reference quantity based on historical execution is established within the same continuous welding path segment to which the current welding point belongs. Specifically, according to the actual execution order of the welding points in the welding sequence, when preparing to calculate the height adjustment quantity of the current welding point (for example, the 5th welding point in the continuous path segment A), the height adjustment quantity actually adopted and recorded at the immediately preceding welding point (i.e. the 4th welding point) is read from the non-volatile memory. This value is extracted and defined as the segment reference height adjustment quantity corresponding to the current welding point. For example, the read segment reference height adjustment quantity is +0.82 mm. This step ensures that within the same geometrically continuous path segment, the adjustment decision of the subsequent welding point is always anchored to the verified and stable execution state of the previous welding point, providing a reliable comparison reference for change constraints.

[0100] The deviation between the newly proposed adjustment quantity of the current welding point and the historical reference benchmark described above, i.e. the height adjustment quantity change value, is calculated. Specifically, the height adjustment quantity calculated based on the height reference data of the current welding point in step two (for example, a newly calculated proposed value is +0.90 mm) is obtained. This value is subtracted from the segment reference height adjustment quantity obtained from step A2 (+0.82 mm) ( +0.90 mm - +0.82 mm). The result of the operation (+0.08 mm) is the height adjustment quantity change value corresponding to the current welding point. This value quantifies the deviation magnitude and direction (positive value for increase, negative value for decrease) of the current calculation proposal relative to the historical execution state.

[0101] The calculated height adjustment amount change value is compared with a safety threshold-change limit value pre-stored in the parameter storage area corresponding to the continuous welding path segment, and an intelligent decision is made based on the comparison result. The specific implementation includes the following sub-steps: first, the pre-set change limit value (for example, the maximum single-step change amount allowed for this segment is ±0.05 mm) is read from the parameter storage area bound to the current continuous welding path segment (such as path segment A). Then, the absolute value of the height adjustment amount change value (|+0.08 mm|=0.08 mm) is calculated and compared with the change limit value (0.05 mm). Since 0.08 mm>0.05 mm, the condition of "absolute value greater than change limit value" is met, so the system triggers the protective alternative logic: taking the reference height adjustment amount within the segment (+0.82 mm) as the basis, superimposing the change limit value (+0.05 mm) selected according to the change direction (positive value), to generate a safe alternative height adjustment amount (+0.87 mm). Conversely, if the absolute value of the calculated change value is not greater than the change limit value, the height adjustment amount determined in step two is directly adopted as the final adopted value. This step is the core of constraint and smoothing, which forces the mutation that exceeds the safe range to be "pulled back" within the allowed change range.

[0102] The height adjustment amount determined through the above comparison and decision-making process (whether it is the alternative value or the original proposed value) is taken as the final adopted height adjustment amount for the current welding point, and the output and loop connection are completed. Specifically, the final determined height adjustment amount (in this case, the alternative value +0.87 mm) is input into the coordinate conversion module to generate the laser focal point position parameter required to drive the laser focal point positioning actuator for the current welding point. This parameter is then passed to the subsequent latch and execution link. At the same time, this final adopted height adjustment amount (+0.87 mm) is immediately updated and stored as the new "reference height adjustment amount within the segment" for the next welding point calculation within the current continuous welding path segment. Subsequently, the process automatically enters the height adjustment amount determination process for the next welding point, forming a closed-loop control sequence that performs historical reference, change calculation, amplitude constraint, and state update within the geometric segmentation, ensuring smooth and stable advancement of the laser focal point along the welding path.

[0103] On the other hand, a height synchronization tracking device for power battery flight welding adopts the height synchronization tracking method in this embodiment. Embodiment

[0104] Compared with Embodiment 1, Embodiment 2 provides an extended method for dealing with height mutations on the workpiece surface. This method is based on the conventional process of obtaining height reference data based on step one and generating height adjustment amount in step two. When a height mutation feature is identified in the front path, the following specific step sequence is activated and executed.

[0105] The recognition of the mutation feature and the definition of the mutation transition zone are performed. In the implementation, after the surface image information is obtained by performing the fast optical imaging on the welding area in the predetermined distance range (for example, 5-10 mm) in front of the current welding spot in step 1, the surface image information is subjected to the enhanced analysis. The analysis focuses on recognizing the linear feature area in the image which extends along the welding path direction and has a significant and continuous edge gradient change or a stable light-dark boundary. For example, by applying an edge detection algorithm (such as Canny operator), a clear boundary line with a gray value change of more than 100 gray levels and a continuous length of more than 3 mm is recognized. The projection of the boundary line on the welding path, i.e., a series of welding spots (for example, 4 subsequent welding spots) to be continuously welded, is determined as an independent processing unit, i.e., a high mutation transition zone.

[0106] For the determined high mutation transition zone, the prospective focal point position trajectory planning is performed. The specific operation includes the following sub-steps: first, the estimated height reference data corresponding to each welding spot in the high mutation transition zone is obtained. The data can be obtained by fast pre-scanning measurement or stereovision depth estimation based on the obtained image information (for example, the heights of the 4 welding spots are estimated as 0.50 mm, 1.00 mm, 1.50 mm, and 2.00 mm, respectively). Second, the laser focal point position parameter adopted by the current welding spot is read (for example, the current focal point is at +0.30 mm in the Z-axis position). Third, taking the current focal point position as the starting point, taking the estimated heights of the welding spots in the high mutation transition zone as the position target reference, and strictly following the welding execution sequence, a trajectory planning algorithm is called. The algorithm calculates a smooth and shock-free displacement trajectory under the premise of meeting the dynamics constraints (such as maximum acceleration and jerk) of the focal point execution mechanism (such as the Z-axis). Finally, the discrete position points corresponding to the welding time of each welding spot in the high mutation transition zone on the trajectory are calculated, and a set of planning laser focal point position parameters corresponding to each welding spot in the high mutation transition zone is generated (for example, the planning sequence is +0.65 mm, +1.10 mm, +1.55 mm, and +1.95 mm).

[0107] The planning spatial position parameters are converted into the standard data format in the control system, i.e., the planning height adjustment amount, and are stored and associated. Specifically, based on the numerical relationship between the planning laser focal point position parameters (such as +0.65 mm) generated above and the height values (such as the theoretical zero point 0.00 mm) corresponding to the reference position of the entire welding sequence, the planning height adjustment amount corresponding to each welding spot is calculated by subtraction operation (the calculation result is +0.65 mm, +1.10 mm, +1.55 mm, and +1.95 mm). Subsequently, the planning height adjustment amounts are stored in a dedicated planning parameter buffer table with the sequence number of the corresponding welding spot as the index, and the association storage of the planning height adjustment amount and the corresponding welding spot is completed.

[0108] In the welding execution phase, the planning parameters for the weld points in the highly mutated transition zone are enabled to replace the regular calculation process. When the welding sequence proceeds to a weld point in the highly mutated transition zone, at the link where step two (calculating the height adjustment amount based on the real-time height reference data) should be performed, the control system will query the planning parameter cache table. The height adjustment amount update process for this weld point in step two will directly use the planning height adjustment amount associated with this weld point read from the table, and immediately generate the laser focal point position parameters based on this value. For example, when welding the first weld point in the highly mutated transition zone, +0.65 mm is directly used as the height adjustment amount to generate the focal point position parameters, thereby skipping the regular calculation process based on real-time measurement of this point.

[0109] After completing the welding of all weld points in the highly mutated transition zone, the system automatically exits the special processing mode and restores the regular control logic. Specifically, when the last weld point (e.g., the fourth) in the highly mutated transition zone is welded, the system will clear the planning parameter cache for subsequent weld points, and make step two determine the height adjustment amount based on the height reference data of the corresponding weld point (obtained in real time through step one). At the same time, the constraint processing of the change in height adjustment amount between adjacent weld points in step five also resumes normal execution. In this way, the system smoothly switches from the "planning execution mode" to the "adaptive measurement and constraint mode" to ensure the continuity and stability of the welding process.

[0110] The above formulas are dimensionless numerical calculations. The formulas are obtained by collecting a large amount of data to simulate the most recent real situation. The preset parameters and threshold values in the formulas are set by a person skilled in the art according to the actual situation.

[0111] The above description is only a preferred embodiment of the present application, and does not limit the present application in any form. Although the present application has been disclosed as above with a preferred embodiment, it is not intended to limit the present application. Any person skilled in the art can make slight changes or modifications to the above disclosed technical content to obtain equivalent embodiments with equivalent changes, without departing from the scope of the technical solution of the present application. Any simple modification, equivalent change and modification of the above embodiments based on the technical essence of the present application are still within the scope of the technical solution of the present application.

Claims

1. A highly synchronized tracking method for power cell flight welding, characterized in that, The method comprises the following steps: Step 1: Obtain the height measurement value of the current to-be-welded region in the inter-weld gap of laser welding, as the height reference data of the current weld point; The inter-weld gap is the time interval between the end time of welding of the previous weld point and the start time of welding of the next weld point; Step 2: Based on the height reference data, determine the height adjustment amount of the current weld point relative to the reference position of the welding sequence, and update the height adjustment amount based on the height adjustment amount adopted by the previous weld point, to generate the laser focal point position parameter corresponding to the current weld point; Step 3: During the duration of laser emission and welding of the current weld point, the laser focal point position is set and kept unchanged according to the laser focal point position parameter, and the laser focal point position is not adjusted based on the real-time height measurement value during the duration; Step 4: After completing the welding of the current weld point, obtain the height measurement value of the region corresponding to the next weld point, as the height reference data of the next weld point; Step 5: When welding multiple weld points in succession, the change of the height adjustment amount between adjacent weld points is constrained, so that the laser focal point positions corresponding to adjacent weld points change continuously and gently along the welding sequence from weld point to weld point.

2. A highly synchronized tracking method for power cell flight welding as claimed in claim 1, wherein, In step 1 of obtaining the height reference data of the current weld point, the following steps are included: According to the current welding process parameters and the material properties of the workpiece, heat diffusion calculation is performed on the heat input of the previous weld point to determine the predicted range of the heat-affected zone generated by the previous weld point; The region located outside the predicted range of the heat-affected zone and in front of the current to-be-welded point along the welding direction is defined as a candidate measurement region; Quick optical imaging is performed on the candidate measurement region to obtain corresponding surface image information, and based on abnormal situations of reflection characteristics, texture continuity or brightness distribution in the surface image information, a sub-region with abnormal surface features is marked; In the valid region after excluding the sub-region with abnormal surface features, at least two measurement positions are selected along the welding direction, and at least one of the measurement positions is located on the extended line of the predicted weld point track; In the inter-weld gap, height measurement values corresponding to the at least two measurement positions are obtained, forming multiple height measurement values of the current weld point; The multiple height measurement values are compared with the average height value of the multiple height measurement values, and the height measurement values with a deviation exceeding a preset height deviation threshold are removed; the remaining height measurement values after removal are averaged to obtain a single height measurement value, and the single height measurement value is taken as the height reference data of the current weld point.

3. A highly synchronized tracking method for power cell flight welding as claimed in claim 2, wherein, The steps of heat diffusion calculation include: Obtain the laser power parameter and the welding speed parameter corresponding to the previous weld point, and calculate the unit length heat input value of the previous weld point in the welding process according to the laser power parameter and the welding speed parameter; Obtain the thermal conductivity parameter, specific heat parameter and density parameter of the workpiece material, and based on the unit length heat input value, the thermal conductivity parameter, the specific heat parameter and the density parameter, calculate the diffusion distance of heat along the welding sequence direction and perpendicular to the welding sequence direction, respectively; Obtain the time point at which the previous weld point completes welding and the time point at which the current weld point starts height measurement, and calculate the time interval between the two time points; According to the time interval, the diffusion distance along the welding sequence direction and the diffusion distance perpendicular to the welding sequence direction are corrected; According to the corrected diffusion distance, the space section covered by the heat diffusion of the previous welding spot in the welding sequence direction and the transverse direction thereof is determined, and the space section is taken as the heat affected zone prediction range corresponding to the previous welding spot.

4. The highly synchronized tracking method for power cell flight welding of claim 1, wherein, Step two, based on the height reference data, generates the laser focal point position parameter corresponding to the current welding spot, including: Based on the preset connection relationship of the adjacent welding spots in the welding sequence, determine the welding path segment to which the current welding spot belongs, and judge whether the current welding spot is the starting welding spot of the welding path segment or the welding spot where the path direction changes; When it is judged that the current welding spot is the starting welding spot of the welding path segment or the welding spot where the path direction changes, based on the height reference data of the current welding spot and the height value corresponding to the welding sequence reference position, the height adjustment amount of the current welding spot is determined, and the height adjustment amount is taken as the height adjustment amount used for updating of the current welding spot; When it is judged that the current welding spot is not the starting welding spot of the welding path segment and the path direction has not changed, based on the height reference data of the current welding spot and the height reference data of the previous welding spot, the relative height change amount between the adjacent welding spots is determined, and the relative height change amount is combined with the height adjustment amount already adopted by the previous welding spot to determine the height adjustment amount used for updating of the current welding spot; Based on the height adjustment amount used for updating, the height adjustment amount is updated based on the height adjustment amount already adopted by the previous welding spot, and the laser focal point position parameter corresponding to the current welding spot is generated.

5. The highly synchronized tracking method for power cell flight welding of claim 1, wherein, Step three, during the duration of laser emission and current welding spot welding, including the steps executed at the start time of the duration and the steps executed at the end time of the duration: At the start time of the duration, the laser focal point position parameter corresponding to the current welding spot is written into the laser focal point position parameter latch area and completed latching; During the latch holding period, the laser focal point position is set according to the laser focal point position parameter in the laser focal point position parameter latch area, and the laser focal point position parameter in the laser focal point position parameter latch area is prohibited from being rewritten; During the latch holding period, the sampling trigger signal of the height measurement channel is subjected to gating processing, so that the height measurement channel does not output real-time height measurement values for laser focal point position updating; At the end time of the duration, the latch is released and the gating processing is released, and the laser focal point position parameter writing and latching process corresponding to the next welding spot is entered.

6. The highly synchronized tracking method for power cell flight welding of claim 1, wherein, Step four, when the height reference data of the next welding spot is obtained after the current welding spot is welded, including: During the welding of the current welding spot, the height measurement position of the area corresponding to the next welding spot is determined in advance; At the time when the laser switches from the emission state to the non-emission state, height measurement at the height measurement position is triggered; At least two height measurement values are continuously obtained at the height measurement position within the same welding spot gap; The at least two height measurement values are subjected to consistency comparison processing, and a single height measurement value is selected; The single height measurement value is recorded as the height reference data of the next welding spot.

7. The highly synchronized tracking method for power cell flight welding of claim 1, wherein, Step five, when a plurality of welding spots are continuously welded, including: A1、based on the spatial coordinate relationship between adjacent welding points in the welding path data, when the welding path direction of adjacent welding points remains continuous and no direction change occurs, the adjacent welding points are determined to belong to the same continuous welding path segment; when the welding path direction changes, the welding sequence is divided into different continuous welding path segments; A2、within the same continuous welding path segment, according to the execution order of the welding points in the welding sequence, the height adjustment amount already adopted when the previous welding point is welded is read as the segment reference height adjustment amount corresponding to the current welding point; A3、the height adjustment amount of the current welding point determined in step two is subtracted from the segment reference height adjustment amount to obtain the height adjustment amount change value corresponding to the current welding point; A4、the height adjustment amount change value is compared with the change limit value stored in the parameter area corresponding to the continuous welding path segment; when the absolute value of the height adjustment amount change value is greater than the change limit value, an alternative height adjustment amount is generated based on the segment reference height adjustment amount and superimposed with the change limit value; when the absolute value of the height adjustment amount change value is not greater than the change limit value, the height adjustment amount determined in step two is adopted; A5、the final height adjustment amount of the current welding point is used to generate the corresponding laser focal point position parameter, and the height adjustment amount determination process for the next welding point is entered.

8. The highly synchronized tracking method for power cell flight welding of claim 1, wherein, In the process of obtaining the height reference data based on step one and executing step two to generate the height adjustment amount, when a height mutation feature is identified on the workpiece surface in front of the current welding point on the welding path, the following steps are further included: based on the surface image information obtained in step one, the welding area within a predetermined distance range in front of the current welding point along the welding path direction is analyzed to identify the area with continuous edge change or light-dark boundary feature, and the continuous multiple welding points corresponding to the coverage are determined as the height mutation transition area; for the height mutation transition area, the estimated height reference data corresponding to each welding point in the height mutation transition area is obtained, and combined with the laser focal point position parameter already adopted by the current welding point, the laser focal point position corresponding to each welding point in the height mutation transition area is calculated according to the welding execution order to generate the planned laser focal point position parameter corresponding to each welding point in the height mutation transition area; based on the numerical relationship between the planned laser focal point position parameter and the height value corresponding to the welding sequence reference position, the planned height adjustment amount corresponding to each welding point in the height mutation transition area is calculated respectively, and the planned height adjustment amount is associated and stored with the corresponding welding point; when welding the welding points in the height mutation transition area, the height adjustment amount updating process for the corresponding welding point in step two directly adopts the planned height adjustment amount associated with the welding point to generate the laser focal point position parameter of the corresponding welding point; after the welding of the welding points in the height mutation transition area is completed, for the subsequent welding points, step two determines the height adjustment amount based on the height reference data of the corresponding welding point again, and continues to perform the constraint processing of the height adjustment amount change between adjacent welding points in step five.

9. A highly synchronized tracking device for power cell flight welding, characterized by, The synchronous tracking device adopts the height synchronous tracking method of any one of claims 1-8.

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