Riveting control method and device

Abstract

Embodiments of the present application provide a riveting control method and device. The method comprises: receiving pre-pressing process data corresponding to a target riveting process, the pre-pressing process data being used to represent a relationship between a force state, a displacement state or at least two of the riveting tool in the pre-pressing stage; determining at least one characteristic position used to represent a preset mechanical state of the riveting tool based on the pre-pressing process data; determining at least one size parameter of a riveting object based on a positional relationship between the characteristic position and a reference position, the reference position being obtained based on an empty riveting operation in a no-load state, and the riveting object at least including a rivet and / or a connected piece; and adjusting at least one riveting process parameter corresponding to the target riveting process based on the size parameter. By identifying the characteristic position in the pre-pressing process data and combining the empty riveting reference position, the actual sizes such as the plate thickness and the rivet length are obtained, so as to dynamically adjust the riveting parameters, and the riveting quality is effectively improved.

Description

Technical Field

[0001] This application relates to the field of riveting technology, and in particular to a riveting control method and apparatus. Background Technology

[0002] In the field of automated riveting processes, precise control of the riveting process is usually required to ensure the consistency and reliability of riveted joints.

[0003] However, in the actual riveting process, due to factors such as material thermal deformation, equipment precision drift, tooling positioning deviation, or environmental fluctuations, problems such as riveting eccentricity, forming size deviation, and excessive connection gap are prone to occur, making it impossible for process parameters to accurately match the actual workpiece state, resulting in the inability to guarantee riveting quality. Summary of the Invention

[0004] This application provides a riveting control method and apparatus to solve the technical problem of inconsistent riveting quality in the prior art.

[0005] In a first aspect, embodiments of this application provide a riveting control method, comprising the following steps.

[0006] Receive preload process data corresponding to the target riveting process, wherein the target riveting process is under load, and the preload process data is used to characterize the force state, displacement state, or at least the relationship between the two of the riveting tool in the preload stage. Based on the pre-compression process data, at least one feature position is determined to characterize the preset mechanical state of the riveting tool; Based on the positional relationship between the feature position and the reference position, at least one dimensional parameter of the riveting object is determined, wherein the reference position is obtained based on an empty riveting operation under no-load conditions, and the riveting object includes at least a rivet and / or a connected component. Based on the dimensional parameters, at least one riveting process parameter corresponding to the target riveting process is adjusted.

[0007] In some embodiments, receiving preload process data corresponding to the target riveting process includes: During the pre-pressing stage of the target riveting process, pressure data of the riveting tool is collected by a pressure sensor, displacement data of the riveting tool during the pre-pressing stage is collected by a first displacement sensor, and / or displacement data of the pressure head inside the riveting tool during the pre-pressing stage is collected by a second displacement sensor; the pressure head is located at the end of the rivet rod and is used to transmit pressure to the rivet; The displacement data of the riveting tool is used as the first pre-compression process data, and / or the displacement data of the pressure head inside the riveting tool is correlated with the pressure data according to time to obtain the second pre-compression process data.

[0008] In some embodiments, based on the pre-compression process data, at least one feature position for characterizing the preset mechanical state of the riveting tool is determined, including: Determine the maximum displacement data in the first pre-compression process data; the maximum displacement data characterizes the displacement distance corresponding to the riveting tool moving from its initial position in the pre-compression stage to contacting the joined parts; and / or, Determine the inflection points in the data of the second pre-compression process, wherein the inflection points include at least a first inflection point and a second inflection point; Wherein, the first inflection point represents the critical mechanical state in which the first elastic mechanism inside the riveting tool is compacted and the second elastic mechanism begins to deform, and the second inflection point represents the critical mechanical state in which the rivet contacts the connected part and begins to apply pressure to the connected part; the first elastic mechanism is an elastic structure inside the riveting tool connected to the rivet rod, the second elastic mechanism is an elastic structure connected in series with the first elastic mechanism, and the second elastic mechanism begins to deform after the first elastic mechanism reaches its maximum deformation.

[0009] In some embodiments, determining the dimensional parameters of at least one riveted object based on the positional relationship between the feature location and the reference location includes: Based on the displacement difference between the maximum displacement data and the reference displacement, the thickness of the joined parts is determined; the reference displacement refers to the displacement amount corresponding to the riveting tool moving from the initial position of the pre-pressing stage to the third reference position during the no-load riveting operation; the third reference position refers to the position corresponding to the riveting tool contacting the worktable during the no-load riveting operation; and / or, The length of the rivet is determined based on the displacement difference between the first inflection point and the second inflection point, and the displacement difference between the first reference position and the second reference position. Wherein, the displacement difference between the first inflection point and the second inflection point represents the displacement of the pressure head during the target riveting process from the start of deformation of the second elastic mechanism to the stage when the rivet contacts the connected part; the first reference position corresponds to the position of the pressure head when the first elastic mechanism is compacted and the second elastic mechanism begins to deform during the no-riveting operation, and the second reference position corresponds to the position of the pressure head when the pressure head contacts the worktable and begins to apply pressure to the worktable during the no-riveting operation; the displacement difference between the first reference position and the second reference position represents the displacement of the pressure head during the no-riveting operation from the start of deformation of the second elastic mechanism to the stage when the pressure head contacts the worktable.

[0010] In some embodiments, determining the inflection point in the second pre-compression process data includes: Geometric feature extraction is performed on the curve corresponding to the second pre-compression process data to obtain multiple candidate inflection points; Within a preset data range near the candidate inflection point, data points that meet preset constraints are identified as the first inflection point and the second inflection point, where the pressure value corresponding to the second inflection point is greater than the pressure value corresponding to the first inflection point. The preset constraints include at least one of the following: The pressure value corresponding to the data point is the minimum value within the preset range, and the pressure value after the data point within the preset range continues to rise until the cumulative increase in pressure value reaches a first preset pressure value; and / or, The pressure value corresponding to the first inflection point is less than the second preset pressure value.

[0011] In some embodiments, geometric feature extraction processing is performed on the curve corresponding to the second preloading process data to obtain multiple candidate inflection points, including: Calculate the vertical distance from each data point on the curve to the first straight line, where the first straight line is the line connecting the start and end points of the curve; The data point with the largest vertical distance is selected as the first candidate inflection point; The curve is divided into a first curve segment and a second curve segment using the first candidate inflection point as the boundary. The perpendicular distance from the data point on the first curve segment to the second straight line and the perpendicular distance from the data point on the second curve segment to the third straight line are calculated. The endpoints of the first curve segment are the starting point and the first candidate inflection point of the curve, the endpoints of the second curve segment are the ending point and the first candidate inflection point of the curve, the second straight line is the straight line connecting the two endpoints of the first curve segment, and the third straight line is the straight line connecting the two endpoints of the second curve segment. The data point with the largest vertical distance on the first curve segment is selected as the second candidate inflection point, and the data point with the largest vertical distance on the second curve segment is selected as the third candidate inflection point.

[0012] In some embodiments, adjusting at least one riveting process parameter corresponding to the target riveting process based on the size parameter includes: Based on the length of the rivet, a target riveting depth is determined, which refers to the expected riveting depth corresponding to the complete embedding of the rivet into the connected parts. During the riveting stage of the target riveting process, a first displacement amount is obtained by a first displacement sensor, which refers to the change in distance between the pressure head and the connected part. A second displacement sensor is also used to obtain a second displacement amount of the pressure head during the riveting stage. The riveting stage refers to the process from when the rivet contacts the connected part to when it is embedded in the connected part. Calculate the difference between the second displacement and the first displacement to obtain the actual riveting value; Based on the difference between the target riveting value and the actual riveting value, adjust the riveting distance of the pressure head and / or adjust the downward speed of the pressure head.

[0013] In some embodiments, adjusting at least one riveting process parameter corresponding to the target riveting process based on the size parameter includes: Based on the thickness of the connected parts, the target clamping force of the riveting tool is adjusted during the pre-pressing stage.

[0014] In some embodiments, the riveting control method further includes: If the dimensional parameters exceed the preset parameter range, an alarm will be issued and the target riveting process will be stopped.

[0015] Secondly, embodiments of this application provide a riveting control device, including the following modules.

[0016] The receiving module is used to receive pre-compression process data corresponding to the target riveting process, wherein the target riveting process is under load, and the pre-compression process data is used to characterize the force state, displacement state, or at least the relationship between the two of the riveting tool in the pre-compression stage. The feature position determination module is used to determine at least one feature position for characterizing the preset mechanical state of the riveting tool based on the pre-compression process data. A size determination module is used to determine the size parameters of at least one riveting object based on the positional relationship between the feature position and the reference position, wherein the reference position is obtained based on an empty riveting operation under no load, and the riveting object includes at least a rivet and / or a connected part. An adjustment module is used to adjust at least one riveting process parameter corresponding to the target riveting process based on the size parameters.

[0017] Thirdly, embodiments of this application provide an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement any of the riveting control methods described above.

[0018] Fourthly, a non-transitory computer-readable storage medium having a computer program stored thereon that, when executed by a processor, implements the riveting control method as described above.

[0019] Fifthly, embodiments of this application also provide a computer program product, including a computer program that, when executed by a processor, implements the riveting control method as described in the first aspect above.

[0020] The riveting control method and apparatus provided in this application receive pre-compression process data corresponding to the target riveting process, determine at least one characteristic position representing the preset mechanical state of the riveting tool, and accurately calculate the dimensional parameters of the riveting object, such as the thickness of the sheet metal and / or the length of the rivet, using the positional relationship between this characteristic position and a reference position obtained based on a no-load riveting operation. Then, the riveting process parameters are adjusted in real time based on these dimensional parameters. This method uses the reference position obtained from a no-load riveting operation as a benchmark and compares it with the characteristic position obtained from a loaded target riveting process. It accurately obtains the dimensional parameters of the riveting object, thereby enabling accurate riveting compensation, improving the stability and consistency of riveting, and enhancing riveting quality. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a flowchart illustrating the riveting control method provided in the embodiments of this application.

[0023] Figure 2 This is a schematic diagram of the second pre-compression process data in a specific example provided in the embodiments of this application.

[0024] Figure 3 This is a schematic diagram of the riveting control device provided in the embodiments of this application.

[0025] Figure 4 This is a schematic diagram of the structure of the electronic device provided in the embodiments of this application. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0027] Figure 1 This is one of the flowcharts illustrating the riveting control method provided in the embodiments of this application, such as... Figure 1As shown in the figure, this application provides a riveting control method. The execution subject of the method can be a controller in the riveting system. The method can include steps 101 to 104.

[0028] Step 101: Receive the pre-compression process data corresponding to the target riveting process. The target riveting process is under load. The pre-compression process data is used to characterize the force state, displacement state, or at least the relationship between the two of the riveting tool in the pre-compression stage.

[0029] Specifically, the target riveting process is the riveting operation that is about to be performed or is being performed, and it is under load, that is, there are rivets in the riveting tools and plates or other connected parts on the worktable.

[0030] The riveting process includes at least a rapid approach phase, a pre-compression phase, and a riveting insertion phase. In the rapid approach phase, the riveting tool descends at the highest safe speed to minimize non-processing time (idle stroke), thereby improving overall machine productivity. Upon reaching the pre-compression start position, the pre-compression phase begins. This phase refers to the process from the start of the pre-compression downward movement of the riveting rod until the rivet just contacts the joined parts or reaches a certain contact force. During the pre-compression phase, data such as pressure and displacement are monitored, and the necessary working conditions for subsequent riveting are calculated, including the dimensional parameters of the riveted object and the riveting process parameters. In the riveting insertion phase, the rivet is embedded into the joined parts, and the final riveting is performed.

[0031] Receive preload process data corresponding to the target riveting process. This preload process data is used to characterize the stress state, displacement state, or at least the relationship between the two of the riveting tool during the preload stage.

[0032] For example, preloading process data can be a pressure-displacement curve that varies with time or stroke, or a set of ordered data points with one-to-one correspondence between pressure and displacement values.

[0033] Preloading process data can be obtained in various ways. For example, displacement sensors can be used to collect displacement data of the rivet gun, rivet rod, and / or rivet, and pressure sensors can be used to collect pressure data at the actuator end of the rivet rod. Preloading process data can then be obtained based on the displacement and pressure data. Alternatively, signals that indirectly characterize pressure, such as motor current, can be used in conjunction with the collected displacement data to deduce the relationship between pressure and displacement, such as a formula or a corresponding curve, thus obtaining the preloading process data.

[0034] Riveting tools can be rivet guns or rivet pens.

[0035] Step 102: Based on the pre-compression process data, determine at least one feature position for characterizing the preset mechanical state of the riveting tool.

[0036] Specifically, this feature location can be directly extracted from the pre-compression process data and is used to characterize the riveting tool in a preset mechanical state. This preset mechanical state can be the state where the riveting tool just contacts the connected part / worktable; or the critical mechanical state where the pre-compression spring inside the riveting tool is fully compressed (i.e., reaches maximum deformation) and the final compression spring begins to deform; or the state where the pressure head at the top of the rivet presses down on the rivet until the rivet just contacts the connected part / worktable, i.e., the mechanical state where the final compression spring is compressed to a certain deformation; or the state where the pressure head is at a preset height from the connected part / worktable; and so on.

[0037] In this embodiment of the application, the riveting tool, such as a rivet gun, includes a housing and an internal transmission component, which includes a rivet rod, a pressure head, and at least two sequentially acting elastic mechanisms.

[0038] For example, the transmission components of a rivet gun consist of a rivet rod, a pressure head, a first elastic mechanism (preload spring), and a second elastic mechanism (final load spring).

[0039] The pressure head is located at the top of the rivet rod and contacts the rivet, and is used to apply pressure to the rivet head.

[0040] The first elastic mechanism (preload spring) is connected to / in contact with the rivet rod and compresses as pressure is applied by the rivet rod until it reaches its maximum displacement, i.e., the first elastic mechanism is fully compressed. The first elastic mechanism is used to provide feedback that the connected workpiece (such as sheet metal) has been positioned and tightened, ensuring that the riveting action is initiated in the correct position and preventing dry riveting or misalignment.

[0041] The second elastic mechanism (final compression spring) is connected in series with the first elastic mechanism. As the rivet is pressed down, it is compressed and begins to deform after being compacted by the first elastic mechanism until the deformation stops after the rivet contacts the connected part.

[0042] Step 103: Based on the positional relationship between the feature position and the reference position, determine the size parameters of at least one riveting object. The reference position is obtained based on an empty riveting operation under no-load conditions. The riveting object includes at least a rivet and / or a connected component.

[0043] Specifically, the reference position is obtained based on a no-load riveting operation. During equipment startup or periodic calibration, the controller directs the riveting tool to complete a downward movement and reach a preset pressure without placing any sheet metal or rivets (i.e., under no-load conditions); this is the no-load riveting operation. During the no-load riveting operation, a set of pre-pressure process data is also generated. This data reflects the mechanical characteristics of the tool itself, such as the physical zero point of the worktable and the free compression stroke of the elastic mechanism. The controller records the position corresponding to the characteristic position described in step 102 under no-load conditions as the reference position.

[0044] For example, during the riveting operation, process data characterizing the force state, displacement state, or at least the relationship between the two of the riveting tool in the pre-compression stage are detected, and reference positions corresponding to the preset mechanical state of the riveting tool in the process data are recorded, such as the data point position corresponding to when the riveting tool just contacts the worktable, the data point position corresponding to the critical node where the pre-compression spring in the riveting tool is fully compressed (i.e. reaches maximum deformation) and the final compression spring begins to deform, the data point position corresponding to when the pressure head presses down on the rivet until the rivet just contacts the worktable, and / or the data point position corresponding to when the pressure head moves down to a preset distance from the worktable, etc.

[0045] Based on the positional relationship between the feature position obtained under load and the reference position obtained under no load, the size parameters of at least one riveted object can be derived.

[0046] The riveting objects include the connected parts and the rivets. The connected parts are the workpieces that are connected by the rivets, which are placed on the worktable and can be materials such as sheet metal.

[0047] Step 104: Based on the size parameters, adjust at least one riveting process parameter corresponding to the target riveting process.

[0048] Specifically, based on the actual dimensional parameters of the riveted object, the controller can automatically correct the relevant riveting process parameters to compensate for the riveting accuracy deviation caused by the dimensional deviation of the riveted object.

[0049] For example, if the actual thickness of the sheet material is detected to be thinner than the nominal value, the controller can appropriately reduce the clamping force during the pre-compression stage to avoid deformation or damage to the sheet material. If the actual thickness of the sheet material is detected to be thicker than the nominal value, the clamping force during the pre-compression stage can be appropriately increased to ensure stable positioning.

[0050] For example, if the actual rivet length is detected to be shorter than the nominal value, the controller can reduce the riveting distance to prevent overpressure. If the actual rivet length is detected to be longer than the nominal value, the controller can increase the riveting distance to ensure the rivet is fully embedded in the sheet metal.

[0051] Riveting process parameters may include the clamping force during the pre-pressing stage, the maximum pressure during the riveting stage, the downward speed of the pressure head, the riveting distance, and the target riveting depth.

[0052] The riveting control method provided in this application measure and calculates the actual dimensions of the riveting object (such as plate thickness and nail length) in real time during the pre-pressing stage, and dynamically adjusts the riveting process parameters based on this. This effectively compensates for system deviations caused by workpiece size tolerances, wear, or installation errors, solves the problem that fixed parameter processes cannot adapt to changes in actual working conditions, resulting in unstable riveting quality, and realizes adaptive control of the riveting process, significantly improving the stability and consistency of riveting quality.

[0053] In some embodiments, receiving pre-compression process data corresponding to the target riveting process may include: during the pre-compression stage of the target riveting process, collecting pressure data of the riveting tool through a pressure sensor, and collecting displacement data of the riveting tool during the pre-compression stage through a first displacement sensor, and / or collecting displacement data of the pressure head inside the riveting tool during the pre-compression stage through a second displacement sensor; the pressure head is located at the end of the rivet rod and is used to transmit pressure to the rivet; using the displacement data of the riveting tool as first pre-compression process data, and / or, corresponding the displacement data of the pressure head inside the riveting tool with the pressure data according to time to obtain second pre-compression process data.

[0054] Specifically, the pre-compression process data can be obtained through pressure sensors and displacement sensors.

[0055] The pressure data applied to the riveting tool can be collected using a pressure sensor. This pressure sensor can be installed between the output shaft of the drive motor and the rivet rod, and its output signal represents the axial force applied to the rivet rod.

[0056] The displacement data of the riveting tool during the pre-loading stage can be collected by a first displacement sensor. The first displacement sensor is an external displacement sensor that can be installed on the frame around the riveting tool to measure the vertical movement distance of the riveting tool, or to measure the distance between the riveting tool and the worktable, thereby obtaining the downward movement distance of the riveting tool, which is the displacement data of the riveting tool.

[0057] The displacement data of the pressure head inside the riveting tool during the pre-pressing stage can be collected by a second displacement sensor. The second displacement sensor can be installed inside the riveting tool to measure the distance between the pressure head and the worktable, thereby obtaining the movement distance of the pressure head, which is the displacement data of the pressure head.

[0058] The controller uses the displacement data of the riveting tool as the first pre-compression process data, and / or correlates the displacement data of the pressure head inside the riveting tool with the pressure data over time to obtain the second pre-compression process data. The first pre-compression process data can be used to obtain the dimensional parameters of the joined parts, and the second pre-compression process data can be used to obtain the dimensional parameters of the rivet.

[0059] The riveting control method provided in this application collects displacement data of the riveting tool and / or displacement data of the internal pressure head, and combines it with pressure data to form pressure-displacement relationship data. This provides a complete and reliable data foundation for subsequent accurate identification of feature positions (such as inflection points), thereby improving the accuracy of the riveting object size calculation.

[0060] In some embodiments, determining at least one characteristic position for characterizing a preset mechanical state of the riveting tool based on the pre-compression process data may include: determining maximum displacement data in the first pre-compression process data; the maximum displacement data characterizing the displacement distance corresponding to the process of the riveting tool moving from the initial position of the pre-compression stage to contacting the connected part; and / or determining inflection points in the second pre-compression process data, the inflection points including at least a first inflection point and a second inflection point; wherein, the first inflection point characterizes the critical mechanical state in which the first elastic mechanism inside the riveting tool is compacted and the second elastic mechanism begins to deform, and the second inflection point characterizes the critical mechanical state in which the rivet contacts the connected part and begins to apply pressure to the connected part; the first elastic mechanism is an elastic structure inside the riveting tool connected to the rivet rod, the second elastic mechanism is an elastic structure connected in series with the first elastic mechanism, and the second elastic mechanism begins to deform after the first elastic mechanism reaches its maximum deformation.

[0061] Specifically, the preloading process data is processed to obtain characteristic positions that characterize the mechanical state of the riveting tool. These characteristic positions can be the positions corresponding to the maximum displacement data or the inflection point positions.

[0062] In some embodiments, after acquiring the first pre-compression process data (riveting tool displacement data), the maximum displacement data in the first pre-compression process data is determined. This maximum displacement data can characterize the displacement value corresponding to the process of the riveting tool moving from the initial position of the pre-compression stage to contacting the joined part (such as a sheet metal). In the pre-compression stage, the riveting tool moves rapidly downward under the action of the drive mechanism, and its displacement increases from the initial position. When the riveting tool contacts the joined part on the worktable, the riveting tool (housing) is fixed at that position and cannot move further. Therefore, this position corresponds to the maximum displacement of the riveting tool.

[0063] The initial position of the pre-compression stage can be set at a preset height from the worktable, and the preset height can be two to five times the standard thickness of the connected parts.

[0064] In some embodiments, after acquiring the second pre-compression process data (data relating head displacement to pressure), the first inflection point and the second inflection point in the second pre-compression process data are determined.

[0065] The first inflection point represents the critical mechanical state in which the first elastic mechanism inside the riveting tool is compacted and the second elastic mechanism begins to deform. After the riveting tool moves to contact the joined parts, as pressure continues to be applied, the first elastic mechanism begins to compress until it reaches its maximum deformation, at which point the first inflection point is reached, and then the second elastic mechanism begins to deform.

[0066] The second inflection point represents the critical state at which the rivet contacts the connected parts and begins to apply pressure to them. After the first elastic mechanism reaches its maximum deformation, the second elastic mechanism begins to deform and gradually compresses. The pressure head pushes the rivet downwards until the rivet contacts the connected parts and begins to apply pressure, at which point the second inflection point is reached.

[0067] Figure 2 This is a schematic diagram of the second pre-compression process data in a specific example provided in the embodiments of this application, such as... Figure 2 As shown, the data for this second pre-compression process is the pressure-head displacement relationship curve. The horizontal axis of the curve represents the head displacement data (i.e., w in the figure), and the vertical axis represents the pressure data (i.e., F in the figure). This curve typically exhibits two distinct inflection points, namely the first and second inflection points in the figure. When the rivet gun moves downwards until the rivet gun housing just contacts the joined part, the housing is fixed in that position and cannot move further.

[0068] As the rivet rod inside the rivet gun is pressed down, the first elastic mechanism begins to compress and deform. During the deformation process, the pressure value oscillates at a low level. When the first elastic mechanism reaches its maximum deformation, it reaches the first inflection point, which corresponds to the first point of abrupt change in slope on the curve.

[0069] After the first elastic mechanism reaches its maximum deformation, the second elastic mechanism located inside the first elastic mechanism begins to deform until the rivet contacts the connected part and begins to apply pressure to the connected part. At this point, the second inflection point is reached, and the pressure increases sharply, corresponding to the second point of abrupt change in slope on the curve.

[0070] The riveting phase begins from the second inflection point.

[0071] The riveting control method provided in this application not only identifies the maximum displacement data of the external displacement, but also precisely defines two inflection points with clear physical meaning from the built-in force-displacement relationship. These inflection points correspond to the critical moments of spring mechanism state transition and rivet contact with the workpiece, respectively, thereby concretizing the abstract feature positions into quantifiable data points that correspond one-to-one with the physical state, providing an accurate identification basis for subsequent precise calculation of workpiece dimensions.

[0072] In some embodiments, determining the dimensional parameters of at least one riveted object based on the positional relationship between the feature position and the reference position may include: determining the thickness of the joined part based on the displacement difference between the maximum displacement data and the reference displacement; the reference displacement refers to the displacement amount corresponding to the riveting tool moving from the initial position of the pre-pressing stage to the third reference position during the no-riveting operation, and the third reference position refers to the position corresponding to the riveting tool contacting the worktable during the no-riveting operation; and / or, determining the length of the rivet based on the displacement difference between the first inflection point and the second inflection point, and the displacement difference between the first reference position and the second reference position; In the above, the displacement difference between the first inflection point and the second inflection point represents the displacement of the pressure head during the target riveting process from the start of deformation of the second elastic mechanism to the contact of the rivet with the connected parts; the first reference position corresponds to the position of the pressure head when the first elastic mechanism is compacted and the second elastic mechanism begins to deform during the no-riveting operation, and the second reference position corresponds to the position of the pressure head when the pressure head contacts the worktable and begins to apply pressure to the worktable during the no-riveting operation; the displacement difference between the first reference position and the second reference position represents the displacement of the pressure head during the no-riveting operation from the start of deformation of the second elastic mechanism to the contact of the pressure head with the worktable.

[0073] Specifically, after obtaining the maximum displacement data ExPos2 in the first pre-compression process data, that is, after obtaining the displacement distance experienced by the riveting tool from the initial position of the pre-compression stage to contact the connected parts, the thickness of the connected parts is determined based on the displacement difference between the maximum displacement data ExPos2 and the reference displacement ExPos1.

[0074] The reference displacement is the displacement of the riveting tool during the no-riveting operation, which corresponds to the movement of the riveting tool from the initial position of the pre-pressing stage to the third reference position. The third reference position is the position when the riveting tool contacts the worktable and / or reaches a certain clamping force during the no-riveting operation.

[0075] For example, in a no-load riveting operation, the displacement of the riveting tool from its initial position during the pre-pressing stage to its position just touching the worktable can be recorded. The node corresponding to the third reference position can be set as the node when the pressure of the pressure head reaches 6 kN during the downward movement. That is, the displacement of the riveting tool is recorded from the initial position, and the recording stops when the pressure reaches 6 kN. The final displacement is the reference displacement ExPos1.

[0076] In some embodiments, during the riveting operation, such as during automatic zeroing, a standard calibration plate with a preset thickness (e.g., 4 mm) is placed under the pressure head. Thus, the thickness of the connected parts is equal to the reference displacement ExPos1 plus the thickness of the standard calibration plate, minus the maximum displacement data ExPos2, i.e., the thickness of the connected parts = ExPos + the thickness of the standard calibration plate - ExPos2.

[0077] After obtaining the first and second inflection points in the second preloading process data, calculate the displacement difference D between the displacement Turn2Pos1 corresponding to the first inflection point and the displacement Turn2Pos2 corresponding to the second inflection point. real D real This refers to the displacement of the pressure head during the riveting process, from the start of deformation of the second elastic mechanism to the contact of the rivet with the joined parts; and the displacement difference D between the first reference position Turn1Pos1 and the second reference position Turn1Pos2 extracted from the data of the no-load riveting operation is calculated. ref D ref This refers to the displacement of the pressure head during the riveting operation, from the moment the second elastic mechanism begins to deform until the pressure head contacts the worktable; then, the displacement difference D is calculated. real With displacement difference D ref The difference between the two values ​​is used as the length of the rivet, i.e., rivet length = D. ref -D real =(Turn1Pos2-Turn1Pos1)-(Turn2Pos2-Turn2Pos1).

[0078] Its physical principle is as follows: During the riveting operation, the deformation stroke of the second elastic mechanism is entirely determined by the mechanical structure and is a fixed value D. ref During the target riveting process with the rivet inserted, the length of the rivet occupies a portion of the stroke of the second elastic mechanism, resulting in a displacement D from the first inflection point to the second inflection point when the rivet is in place. real Less than D ref The difference precisely corresponds to the length of the rivet.

[0079] The riveting control method provided in this application constructs a displacement difference comparison model of key positions or states under load and unload conditions, converting physical quantities that are difficult to measure directly (such as plate thickness, nail length, etc.) into easily calculable displacement difference values. It provides an indirect but accurate measurement method, effectively extracting workpiece size information from signals containing system noise and mechanical deviations, making dynamic compensation possible.

[0080] In some embodiments, determining the inflection point in the second pre-compression process data may include: performing geometric feature extraction processing on the curve corresponding to the second pre-compression process data to obtain multiple candidate inflection points; within a preset data range near the candidate inflection points, determining data points that satisfy preset constraints as a first inflection point and a second inflection point, wherein the pressure value corresponding to the second inflection point is greater than the pressure value corresponding to the first inflection point; wherein the preset constraints include at least one of the following: the pressure value corresponding to the data point is the minimum value within the preset range, and the pressure value after the data point within the preset range continues to rise and the cumulative increase in pressure value reaches a first preset pressure value; and / or, the pressure value corresponding to the first inflection point is less than a second preset pressure value.

[0081] Specifically, a two-stage detection method of first coarse screening and then fine positioning can be used to identify the inflection point in the data of the second pre-compression process, ensuring that the inflection point can still be stably captured in noisy production data.

[0082] The first and second inflection points exhibit significant geometric deviations on the curve (pressure-displacement curve) corresponding to the second preloading process data (locations where the curve shape changes significantly). Therefore, in the first stage of geometric coarse screening, geometric feature extraction is performed on the curve corresponding to the second preloading process data to locate candidate locations that may be inflection points from the global curve, obtaining multiple candidate inflection points. This narrows the inflection point search range from the entire curve to a very few regions, reducing the computational overhead and risk of misjudgment in subsequent fine-grained searches.

[0083] In the second stage of physical precision positioning, using constraints specifically designed for the riveting process, a preset data range near the candidate inflection point is used as a scanning window. Within the preset data range, the data points are verified to ensure they meet the preset constraints. For example, scanning is performed within a range of 2.0 mm before and after the candidate inflection point to determine the final first and second inflection points.

[0084] Preset constraints must include at least one or more of the following: Valley feature constraint. This requires that the pressure value corresponding to the data point is the minimum value within a preset data range (the domain of the data point), meaning the data point is the turning point where the curve transitions from a downward or flat segment to an upward segment.

[0085] Trend constraint. This requires a sustained and steep upward trend to the right of the data point, with the cumulative increase in pressure value reaching a first preset pressure value, such as 1.0 kN.

[0086] Noise reduction processing. Minor sawtooth fluctuations are allowed on the curve, but if a drop (i.e., a downward step) exceeding a preset amplitude (e.g., 0.0002 mm) is observed during the pressure rise, the data point is considered a false inflection point and is excluded. This condition filters out false upward trends caused by noise interference.

[0087] Threshold limitation. For the first inflection point (i.e., the earlier inflection point), the corresponding pressure value must be less than the second preset pressure value. This is because the first inflection point corresponds to the moment when the first elastic mechanism compacts and the second elastic mechanism begins to deform. At this time, the pressure is very small (only overcoming the spring preload), much less than the final riveting pressure. This limitation prevents the system from misjudging the steep rise near the later pressure peak as the first inflection point.

[0088] For example, apply the above constraints to each data point within a preset data range near the candidate inflection point in turn, find the first data point that simultaneously satisfies all the unexcluded conditions, and determine it as the first inflection point; then continue searching backward to find data points that satisfy the same conditions (but require that their pressure value is significantly greater than that of the first inflection point), and determine them as the second inflection point.

[0089] If no valid point is found within a search window, the system will automatically expand the preset data range or adjust the threshold parameters to ensure that at least two inflection points can be stably identified.

[0090] The riveting control method provided in this application, through the combination of geometric coarse screening and physical fine positioning, effectively solves the impact of noise interference and irregular curve shape on inflection point positioning. Geometric coarse screening can quickly find the location of significant changes in curve shape, while physical fine positioning eliminates misjudgments caused by noise through constraints derived from mechanical motion principles (such as valley bottom characteristics and cumulative rise). Thus, even in harsh production environments, it can stably and accurately capture the true physical inflection point, ensuring the reliability of subsequent dimensional calculations.

[0091] In some embodiments, geometric feature extraction processing is performed on the curve corresponding to the second pre-compression process data to obtain multiple candidate inflection points. This may include: calculating the vertical distance from each data point on the curve to a first straight line, where the first straight line refers to the straight line connecting the start and end points of the curve; selecting the data point with the largest vertical distance as the first candidate inflection point; dividing the curve into a first curve segment and a second curve segment with the first candidate inflection point as the boundary, and calculating the vertical distance from the data point on the first curve segment to the second straight line and the vertical distance from the data point on the second curve segment to the third straight line; wherein, the endpoints of the first curve segment are the start point and the first candidate inflection point of the curve, the endpoints of the second curve segment are the end point and the first candidate inflection point, the second straight line refers to the straight line connecting the two endpoints of the first curve segment, and the third straight line refers to the straight line connecting the two endpoints of the second curve segment; selecting the data point with the largest vertical distance on the first curve segment as the second candidate inflection point, and selecting the data point with the largest vertical distance on the second curve segment as the third candidate inflection point.

[0092] Specifically, in the first stage, a variant of the Curve Reduction (Ramer Douglas Peucker, RDP) algorithm can be used for geometric feature extraction. By recursively segmenting the curve and finding the farthest point in each segment, the shape features of the curve can be extracted efficiently.

[0093] First, connect the starting point and the ending point of the pressure-head displacement relationship curve (second pre-compression process data) to obtain the first straight line, and calculate the vertical distance from all points on the curve to the first straight line.

[0094] Then, the point with the largest vertical distance is determined as the first candidate inflection point. Using the first candidate inflection point as the boundary, the curve is divided into a first curve segment and a second curve segment, corresponding to the left and right intervals of the first candidate inflection point, respectively. Connecting the two endpoints of the first curve segment (the starting point of the curve and the first candidate inflection point) yields the second straight line, and connecting the two endpoints of the second curve segment (the first candidate inflection point and the ending point of the curve) yields the third straight line.

[0095] Calculate the perpendicular distance from the data point on the first curve segment to the second straight line, and the perpendicular distance from the data point on the second curve segment to the third straight line. Determine the data point on the first curve segment with the largest perpendicular distance to the second straight line as the second candidate inflection point, and the data point on the second curve segment with the largest perpendicular distance to the third straight line as the third candidate inflection point. Thus, through one curve segmentation, three candidate inflection points are obtained: one globally farthest point and two locally farthest points.

[0096] In some embodiments, after obtaining the above three candidate inflection points, intelligent decision-making can be used to further select the two RDP anchor points that are most similar to the inflection points from the three candidate inflection points as the final candidate inflection points.

[0097] The riveting control method provided in this application recursively finds the point on the curve farthest from the straight line, enabling rapid identification of the location where the curve's geometry changes most drastically. Even inflection points located in different segments of the curve can be effectively captured. This divide-and-conquer strategy greatly improves the efficiency and accuracy of candidate inflection point selection, providing high-quality input for subsequent physical precision positioning and forming the foundation of the entire two-stage inflection point recognition algorithm.

[0098] In some embodiments, adjusting at least one riveting process parameter corresponding to the target riveting process based on the size parameter may include: determining a target riveting value based on the length of the rivet, the target riveting value referring to the expected riveting depth corresponding to the rivet being fully embedded in the connected parts; during the riveting stage of the target riveting process, acquiring a first displacement amount through a first displacement sensor, the first displacement amount referring to the change in distance between the pressure head and the connected parts, and acquiring a second displacement amount of the pressure head during the riveting stage through a second displacement sensor; the riveting stage referring to the process from the moment the rivet contacts the connected parts to the moment it is embedded in the connected parts; calculating the difference between the second displacement amount and the first displacement amount to obtain the actual riveting value; and adjusting the pressing distance of the pressure head and / or adjusting the downward speed of the pressure head based on the difference between the target riveting value and the actual riveting value.

[0099] Specifically, after obtaining the length of the rivet, riveting compensation can also be performed based on the length of the rivet.

[0100] First, the target anchoring value S target It can be set to detect the length of the rivet (the length of the rivet head plus the rivet shank), that is, the actual length of the rivet.

[0101] During the riveting phase of the target riveting process, the first displacement amount ExPos is collected by the first displacement sensor (i.e., the external displacement sensor). out The first displacement refers to the change in distance between the indenter and the connected part; and the second displacement Pos of the indenter during the riveting stage is collected by the second displacement sensor (i.e., the built-in displacement sensor). in Calculate the difference between the second displacement and the first displacement to obtain the actual riveting value S. act S act =Pos in -ExPos outDuring the riveting process, the C-clamp and other support structures undergo elastic deformation due to the enormous force, causing the actual feed of the indenter to be less than the theoretical feed of the drive mechanism. Therefore, by calculating the second displacement and subtracting the external first displacement, the influence of deformation on the riveting depth can be suppressed from the stroke, thus obtaining the true riveting depth.

[0102] Finally, based on the difference between the target riveting value and the actual riveting value, i.e., S target -S act Adjusting the riveting distance of the pressure head and / or adjusting the downward speed of the pressure head can achieve riveting compensation.

[0103] In some embodiments, a proportional-integral-differential (PID) closed-loop algorithm is also used for dynamic velocity planning: the error Error = S target -S act The data is input to the PID controller in real time, which outputs a speed command to the drive motor, thereby dynamically adjusting the downward speed of the compressor.

[0104] Specific dynamic compensation actions may include: automatically increasing the pressure head stroke and descending at a higher speed when the error is large to quickly approach the target riveting value; and / or automatically and smoothly decelerating when the error is close to zero to prevent overpressure or impact. This dynamic compensation strategy ensures that the actual riveting value can converge accurately and smoothly to the target riveting value, guaranteeing the final riveting quality even in the face of interference factors such as C-clamp deformation.

[0105] The riveting control method provided in this application successfully reduces the error caused by the deformation of mechanical structures (such as C-clamps) during high-pressure riveting by introducing differential measurement using internal and external displacement sensors. This allows the actual riveting value to more accurately reflect the actual position of the pressure head relative to the workpiece. Simultaneously, error-based closed-loop control (such as PID speed programming) achieves smooth and precise control of the riveting depth, effectively avoiding insufficient riveting due to deformation or overpressure due to impact, thereby ensuring the final riveting quality and consistency.

[0106] In some embodiments, adjusting at least one riveting process parameter corresponding to the target riveting process based on the size parameter may include: adjusting the target clamping force of the riveting tool during the pre-pressing stage based on the thickness of the joined parts.

[0107] Specifically, the riveting compensation operation also includes: after obtaining the thickness of the connected parts, adjusting the target clamping force of the riveting tool during the pre-pressing stage based on the thickness of the connected parts.

[0108] For example, when the actual sheet thickness is calculated to be 1.5 mm, while the standard thickness is 2.0 mm, the sheet's rigidity is relatively weakened due to the thinner sheet. If the original 10 kN clamping force is still used during the pre-compression stage, it may cause excessive deformation or even damage to the thin sheet. In this case, the controller can automatically reduce the target clamping force to 8 kN according to the preset mapping relationship, thereby avoiding damage while ensuring reliable positioning of the sheet. Conversely, for thicker sheets, the clamping force can be appropriately increased to ensure positioning stability. This adjustment mechanism makes the pre-compression stage's working condition detection more adaptable.

[0109] The riveting control method provided in this application dynamically adjusts the target clamping force during the pre-pressing stage according to the measured plate thickness, ensuring that plates of different thicknesses can obtain an appropriate initial clamping state. This avoids positioning errors or plate damage caused by insufficient or excessive pre-pressing force, and improves the adaptability of the pre-pressing stage working condition detection.

[0110] In some embodiments, the riveting control method may further include: issuing an alarm and stopping the target riveting process when the size parameter exceeds a preset parameter range.

[0111] Specifically, it also includes an exception handling mechanism that issues an alarm and stops the target riveting process if the size parameters of at least one riveting object exceed the corresponding preset parameter range.

[0112] For example, after calculating the actual thickness of the component to be connected, the thickness of the component to be connected is compared with a preset thickness range. If the thickness of the component to be connected exceeds the preset thickness range, an alarm is issued and the target riveting process is stopped. If the calculated thickness of the component to be connected is 3.1 mm, the standard plate thickness is 2.5 mm, and the allowable thickness deviation is ±0.5 mm, that is, the preset thickness range is 2 mm to 3 mm, it can be seen that the calculated thickness of the component to be connected exceeds the preset thickness range.

[0113] For example, after calculating the actual length of the rivet, the rivet length is compared with the preset rivet length range. If the length of the rivet exceeds the preset rivet length range, an alarm is issued and the target riveting process is stopped.

[0114] An alarm can be issued by displaying a value exceeding the limit warning on the user interface; at the same time as issuing the alarm, the current target riveting process is forcibly stopped to prevent damage to parts or mechanical impact due to data errors.

[0115] If the obtained dimensional parameters of the riveting object do not exceed the corresponding preset parameter range, the current working condition is determined to be normal, and the target riveting process continues.

[0116] The riveting control method provided in this application, by setting an abnormal alarm and shutdown mechanism based on the dimensional parameter, allows the system to stop in time before performing riveting actions that may cause damage when the workpiece size is abnormal (such as incorrect material, misalignment, or wear). This effectively avoids serious consequences such as equipment collisions, mold damage, or product scrap caused by using workpieces of incorrect size or tool failure, significantly improving the safety and economy of the production process.

[0117] Figure 3 This is a schematic diagram of the riveting control device provided in the embodiments of this application, as shown below. Figure 3 As shown in the figure, this application provides a riveting control device, which may include a receiving module 301, a feature position determination module 302, a size determination module 303, and an adjustment module 304.

[0118] The receiving module 301 can be used to receive pre-compression process data corresponding to the target riveting process, wherein the target riveting process is under load, and the pre-compression process data is used to characterize the force state, displacement state, or at least the relationship between the two of the riveting tool in the pre-compression stage; the feature position determination module 302 is used to determine at least one feature position for characterizing the preset mechanical state of the riveting tool based on the pre-compression process data; the size determination module 303 is used to determine at least one size parameter of the riveting object based on the positional relationship between the feature position and the reference position, wherein the reference position is obtained based on the no-load riveting operation, and the riveting object includes at least a rivet and / or the connected part; the adjustment module 304 is used to adjust at least one riveting process parameter corresponding to the target riveting process based on the size parameter.

[0119] In some embodiments, the receiving module 301 may include a first acquisition submodule and a first determination submodule. The first acquisition submodule can be used in the pre-pressing stage of the target riveting process to collect pressure data of the riveting tool through a pressure sensor, and to collect displacement data of the riveting tool in the pre-pressing stage through a first displacement sensor, and / or to collect displacement data of the pressure head inside the riveting tool in the pre-pressing stage through a second displacement sensor; the pressure head is located at the end of the rivet rod and is used to transmit pressure to the rivet. The first determination submodule can be used to use the displacement data of the riveting tool as first pre-pressing process data, and / or to correlate the displacement data of the pressure head inside the riveting tool with the pressure data according to time to obtain second pre-pressing process data.

[0120] In some embodiments, the feature position determination module 302 may include a second determination submodule and a third determination submodule. The second determination submodule may be used to determine the maximum displacement data in the first pre-compression process data; the maximum displacement data characterizes the displacement distance corresponding to the process of the riveting tool moving from the initial position of the pre-compression stage to contacting the connected part; and / or, the third determination submodule may be used to determine the inflection point in the second pre-compression process data, the inflection point including at least a first inflection point and a second inflection point; wherein, the first inflection point characterizes the critical mechanical state in which the first elastic mechanism inside the riveting tool is compacted and the second elastic mechanism begins to deform, and the second inflection point characterizes the critical mechanical state in which the rivet contacts the connected part and begins to apply pressure to the connected part; the first elastic mechanism is an elastic structure inside the riveting tool connected to the rivet rod, the second elastic mechanism is an elastic structure connected in series with the first elastic mechanism, and the second elastic mechanism begins to deform after the first elastic mechanism reaches its maximum deformation.

[0121] In some embodiments, the size determination module 303 may include a fourth determination submodule and a fifth determination submodule. The fourth determination submodule may be used to determine the thickness of the joined part based on the displacement difference between the maximum displacement data and the reference displacement; the reference displacement refers to the displacement amount corresponding to the riveting tool moving from the initial position of the pre-pressing stage to the third reference position during the no-riveting operation, and the third reference position refers to the position corresponding to the riveting tool contacting the worktable during the no-riveting operation; and / or, the fifth determination submodule may be used to determine the length of the rivet based on the displacement difference between the first inflection point and the second inflection point, and the displacement difference between the first reference position and the second reference position; wherein, the displacement difference between the first inflection point and the second inflection point... The displacement difference characterizes the displacement of the pressure head during the target riveting process, from the start of deformation of the second elastic mechanism to the contact of the rivet with the connected parts; the first reference position corresponds to the position of the pressure head when the first elastic mechanism is compacted and the second elastic mechanism begins to deform during the no-riveting operation, and the second reference position corresponds to the position of the pressure head when the pressure head contacts the worktable and begins to apply pressure to the worktable during the no-riveting operation; the displacement difference between the first reference position and the second reference position characterizes the displacement of the pressure head during the no-riveting operation, from the start of deformation of the second elastic mechanism to the contact of the pressure head with the worktable.

[0122] In some embodiments, the third determining submodule may include a feature extraction unit and a determining unit. The feature extraction unit may be used to perform geometric feature extraction processing on the curve corresponding to the second pre-compression process data to obtain multiple candidate inflection points; the determining unit may be used to determine, within a preset data range near the candidate inflection points, a data point satisfying a preset constraint condition as a first inflection point and a second inflection point, wherein the pressure value corresponding to the second inflection point is greater than the pressure value corresponding to the first inflection point; wherein the preset constraint condition includes at least one of the following: the pressure value corresponding to the data point is the minimum value within the preset range, and the pressure value after the data point within the preset range continues to rise and the cumulative increase in pressure value reaches a first preset pressure value; and / or, the pressure value corresponding to the first inflection point is less than a second preset pressure value.

[0123] In some embodiments, the feature extraction unit may include a first calculation subunit, a first determination subunit, a second calculation subunit, and a second determination subunit. The first calculation subunit is used to calculate the vertical distance from each data point on the curve to a first straight line, where the first straight line connects the start and end points of the curve. The first determination subunit is used to select the data point with the largest vertical distance as a first candidate inflection point. The second calculation subunit is used to divide the curve into a first curve segment and a second curve segment, using the first candidate inflection point as a boundary, and to calculate the vertical distance from the data points on the first curve segment to the second straight line, and the vertical distance from the data points on the second curve segment to a third straight line. The endpoints of the first curve segment are the start point and the first candidate inflection point, the endpoints of the second curve segment are the end point and the first candidate inflection point, the second straight line connects the two endpoints of the first curve segment, and the third straight line connects the two endpoints of the second curve segment. The second determination subunit is used to select the data point with the largest vertical distance on the first curve segment as a second candidate inflection point and the data point with the largest vertical distance on the second curve segment as a third candidate inflection point.

[0124] In some embodiments, the adjustment module 304 may include: a sixth determining submodule, which can be used to determine a target riveting value based on the length of the rivet, the target riveting value referring to the expected riveting depth corresponding to the complete embedding of the rivet into the connected component; a second acquiring submodule, which can be used to acquire a first displacement amount through a first displacement sensor during the riveting stage of the target riveting process, the first displacement amount referring to the change in distance between the pressure head and the connected component, and acquire a second displacement amount of the pressure head during the riveting stage through a second displacement sensor; the riveting stage referring to the process from the moment the rivet contacts the connected component to the moment it is embedded into the connected component; a calculation submodule, which can be used to calculate the difference between the second displacement amount and the first displacement amount to obtain the actual riveting value; and a first adjusting submodule, which can be used to adjust the riveting distance of the pressure head and / or adjust the downward speed of the pressure head based on the difference between the target riveting value and the actual riveting value.

[0125] In some embodiments, the adjustment module 304 may further include a second adjustment submodule, which can be used to adjust the target clamping force of the riveting tool during the pre-pressing stage based on the thickness of the connected parts.

[0126] In some embodiments, an error reporting module may also be included, which can be used to issue an alarm and stop the target riveting process when the size parameter exceeds the preset parameter range.

[0127] Specifically, the riveting control device provided in this application embodiment can implement all the method steps implemented in the above riveting control method embodiment and can achieve the same technical effect. Here, the parts that are the same as those in the method embodiment and the beneficial effects will not be described in detail.

[0128] It should be noted that the division of units / modules in the above embodiments of this application is illustrative and only represents one logical functional division. In actual implementation, other division methods may be used. Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated units described above can be implemented in hardware or as software functional units.

[0129] Figure 4 This is a schematic diagram of the structure of the electronic device provided in the embodiments of this application, such as... Figure 4As shown, the electronic device may include: a processor 401, a communication interface 402, a memory 403, and a communication bus 404, wherein the processor 401, the communication interface 402, and the memory 403 communicate with each other through the communication bus 404. The processor 401 can call logical instructions in the memory 403 to execute a riveting control method, which may include: receiving state change feature information during the target riveting process, the state change feature information reflecting the change in the interaction state between the riveting tool and the riveted workpiece; extracting at least two feature points characterizing different riveting states based on the state change feature information; determining the size of at least one of the riveted workpieces based on the spatial relationship between the at least two feature points; and adjusting the process parameters corresponding to the target riveting process based on the size of at least one of the riveted workpieces.

[0130] Specifically, the processor 401 can be a central processing unit (CPU), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or a complex programmable logic device (CPLD). The processor can also adopt a multi-core architecture.

[0131] When the logical instructions in memory 403 can be implemented as software functional units and sold or used as independent products, they can be stored in a processor-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) or processor to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0132] In some embodiments, a computer program product is also provided, comprising a computer program that can be stored on a non-transitory computer-readable storage medium. When the computer program is executed by a processor, the computer is able to execute the riveting control method provided in the above-described method embodiments. The method may include: receiving pre-compression process data corresponding to a target riveting process, wherein the target riveting process is under load, and the pre-compression process data is used to characterize the force state, displacement state, or at least the relationship between the two of the riveting tool during the pre-compression stage; determining at least one feature position for characterizing a preset mechanical state of the riveting tool based on the pre-compression process data; determining at least one dimensional parameter of a riveting object based on the positional relationship between the feature position and a reference position, wherein the reference position is obtained based on an unloaded riveting operation, and the riveting object includes at least a rivet and / or a connected component; and adjusting at least one riveting process parameter corresponding to the target riveting process based on the dimensional parameter.

[0133] Specifically, the computer program product provided in this application embodiment can implement all the method steps implemented in the above method embodiments and can achieve the same technical effect. Here, the parts that are the same as those in the method embodiments and the beneficial effects will not be described in detail.

[0134] In some embodiments, a computer-readable storage medium is also provided, the computer-readable storage medium storing a computer program for causing a computer to execute the riveting control method provided in the above-described method embodiments. The method includes: receiving pre-compression process data corresponding to a target riveting process, the target riveting process being under load, the pre-compression process data being used to characterize the force state, displacement state, or at least the relationship between the two of a riveting tool during the pre-compression stage; determining at least one feature position for characterizing a preset mechanical state of the riveting tool based on the pre-compression process data; determining at least one dimensional parameter of a riveting object based on the positional relationship between the feature position and a reference position, the reference position being obtained based on an unloaded riveting operation, the riveting object including at least a rivet and / or a connected component; and adjusting at least one riveting process parameter corresponding to the target riveting process based on the dimensional parameter.

[0135] Specifically, the computer-readable storage medium provided in the embodiments of this application can implement all the method steps implemented in the above method embodiments and can achieve the same technical effect. Here, the parts that are the same as those in the method embodiments and the beneficial effects will not be described in detail.

[0136] It should be noted that the computer-readable storage medium can be any available medium or data storage device that the processor can access, including but not limited to magnetic storage (e.g., floppy disk, hard disk, magnetic tape, magneto-optical disk (MO)), optical storage (e.g., CD, DVD, BD, HVD), and semiconductor storage (e.g., ROM, EPROM, EEPROM, non-volatile memory (NAND FLASH), solid-state drive (SSD)).

[0137] It should also be noted that the terms "first," "second," etc., in the embodiments of this application are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that such terms can be used interchangeably where appropriate so that the embodiments of this application can be implemented in an order other than those illustrated or described herein, and the objects distinguished by "first" and "second" are usually of the same class, and the number of objects is not limited. For example, the first object can be one or more.

[0138] In the embodiments of this application, the term "and / or" describes the relationship between associated objects, indicating that three relationships can exist. For example, A and / or B can represent three cases: A alone, A and B simultaneously, and B alone. The character " / " generally indicates that the preceding and following associated objects have an "or" relationship.

[0139] In the embodiments of this application, the term "multiple" refers to two or more, and other quantifiers are similar.

[0140] In this application's embodiments, "determine B based on A" means that factor A must be considered when determining B. It is not limited to "B can be determined based solely on A," but should also include: "determine B based on A and C," "determine B based on A, C, and E," "determine C based on A, and further determine B based on C," etc. Additionally, it can include using A as a condition for determining B, for example, "when A meets the first condition, determine B using the first method"; another example, "when A meets the second condition, determine B," etc.; another example, "when A meets the third condition, determine B based on the first parameter," etc. Of course, it can also be a condition where A is a factor in determining B, for example, "when A meets the first condition, determine C using the first method, and further determine B based on C," etc.

[0141] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product implemented on one or more computer-usable storage media (including, but not limited to, disk storage and optical storage) containing computer-usable program code.

[0142] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer-executable instructions. These computer-executable instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0143] These processor-executable instructions may also be stored in a processor-readable memory that can direct a computer or other programmable data processing device to operate in a particular manner, such that the instructions stored in the processor-readable memory produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0144] These processors can execute instructions that can also be loaded onto a computer or other programmable data processing device, causing a series of operational steps to be performed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable device for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0145] Obviously, those skilled in the art can make various modifications and variations to the embodiments of this application without departing from the spirit and scope of this application. Therefore, if these modifications and variations to the embodiments of this application fall within the scope of the claims of this application and their equivalents, this application also intends to include these modifications and variations.

Claims

1. A riveting control method, characterized in that, include: Receive preload process data corresponding to the target riveting process, wherein the target riveting process is under load, and the preload process data is used to characterize the force state, displacement state, or at least the relationship between the two of the riveting tool in the preload stage. Based on the pre-compression process data, at least one feature position is determined to characterize the preset mechanical state of the riveting tool; Based on the positional relationship between the feature position and the reference position, at least one dimensional parameter of the riveting object is determined, wherein the reference position is obtained based on an empty riveting operation under no-load conditions, and the riveting object includes at least a rivet and / or a connected component. Based on the dimensional parameters, at least one riveting process parameter corresponding to the target riveting process is adjusted.

2. The riveting control method according to claim 1, characterized in that, The received pre-compression process data corresponding to the target riveting process includes: During the pre-pressing stage of the target riveting process, pressure data of the riveting tool is collected by a pressure sensor, displacement data of the riveting tool during the pre-pressing stage is collected by a first displacement sensor, and / or displacement data of the pressure head inside the riveting tool during the pre-pressing stage is collected by a second displacement sensor; the pressure head is located at the end of the rivet rod and is used to transmit pressure to the rivet; The displacement data of the riveting tool is used as the first pre-compression process data, and / or the displacement data of the pressure head inside the riveting tool is correlated with the pressure data according to time to obtain the second pre-compression process data.

3. The riveting control method according to claim 2, characterized in that, The step of determining at least one feature position for characterizing the preset mechanical state of the riveting tool based on the pre-compression process data includes: Determine the maximum displacement data in the first pre-compression process data; the maximum displacement data characterizes the displacement distance corresponding to the riveting tool moving from its initial position in the pre-compression stage to contacting the joined parts; and / or, Determine the inflection points in the data of the second pre-compression process, wherein the inflection points include at least a first inflection point and a second inflection point; Wherein, the first inflection point represents the critical mechanical state in which the first elastic mechanism inside the riveting tool is compacted and the second elastic mechanism begins to deform, and the second inflection point represents the critical mechanical state in which the rivet contacts the connected part and begins to apply pressure to the connected part; the first elastic mechanism is an elastic structure inside the riveting tool connected to the rivet rod, the second elastic mechanism is an elastic structure connected in series with the first elastic mechanism, and the second elastic mechanism begins to deform after the first elastic mechanism reaches its maximum deformation.

4. The riveting control method according to claim 3, characterized in that, Determining the dimensional parameters of at least one riveted object based on the positional relationship between the feature position and the reference position includes: Based on the displacement difference between the maximum displacement data and the reference displacement, the thickness of the joined parts is determined; the reference displacement refers to the displacement amount corresponding to the riveting tool moving from the initial position of the pre-pressing stage to the third reference position during the no-load riveting operation; the third reference position refers to the position corresponding to the riveting tool contacting the worktable during the no-load riveting operation; and / or, The length of the rivet is determined based on the displacement difference between the first inflection point and the second inflection point, and the displacement difference between the first reference position and the second reference position. Wherein, the displacement difference between the first inflection point and the second inflection point represents the displacement of the pressure head during the target riveting process from the start of deformation of the second elastic mechanism to the stage when the rivet contacts the connected part; the first reference position corresponds to the position of the pressure head when the first elastic mechanism is compacted and the second elastic mechanism begins to deform during the no-riveting operation, and the second reference position corresponds to the position of the pressure head when the pressure head contacts the worktable and begins to apply pressure to the worktable during the no-riveting operation; the displacement difference between the first reference position and the second reference position represents the displacement of the pressure head during the no-riveting operation from the start of deformation of the second elastic mechanism to the stage when the pressure head contacts the worktable.

5. The riveting control method according to claim 3, characterized in that, Determining the inflection point in the second pre-compression process data includes: Geometric feature extraction is performed on the curve corresponding to the second pre-compression process data to obtain multiple candidate inflection points; Within a preset data range near the candidate inflection point, data points that meet preset constraints are identified as the first inflection point and the second inflection point, where the pressure value corresponding to the second inflection point is greater than the pressure value corresponding to the first inflection point. The preset constraints include at least one of the following: The pressure value corresponding to the data point is the minimum value within the preset range, and the pressure value after the data point within the preset range continues to rise until the cumulative increase in pressure value reaches a first preset pressure value; and / or, The pressure value corresponding to the first inflection point is less than the second preset pressure value.

6. The riveting control method according to claim 3, characterized in that, The geometric feature extraction process is performed on the curve corresponding to the second preloading process data to obtain multiple candidate inflection points, including: Calculate the vertical distance from each data point on the curve to the first straight line, where the first straight line is the line connecting the start and end points of the curve; The data point with the largest vertical distance is selected as the first candidate inflection point; The curve is divided into a first curve segment and a second curve segment using the first candidate inflection point as the boundary. The perpendicular distance from the data point on the first curve segment to the second straight line and the perpendicular distance from the data point on the second curve segment to the third straight line are calculated. The endpoints of the first curve segment are the starting point and the first candidate inflection point of the curve, the endpoints of the second curve segment are the ending point and the first candidate inflection point of the curve, the second straight line is the straight line connecting the two endpoints of the first curve segment, and the third straight line is the straight line connecting the two endpoints of the second curve segment. The data point with the largest vertical distance on the first curve segment is selected as the second candidate inflection point, and the data point with the largest vertical distance on the second curve segment is selected as the third candidate inflection point.

7. The riveting control method according to claim 4, characterized in that, The adjustment of at least one riveting process parameter corresponding to the target riveting process based on the size parameters includes: Based on the length of the rivet, a target riveting depth is determined, which refers to the expected riveting depth corresponding to the complete embedding of the rivet into the connected parts. During the riveting stage of the target riveting process, a first displacement amount is obtained by a first displacement sensor, which refers to the change in distance between the pressure head and the connected part. A second displacement sensor is also used to obtain a second displacement amount of the pressure head during the riveting stage. The riveting stage refers to the process from when the rivet contacts the connected part to when it is embedded in the connected part. Calculate the difference between the second displacement and the first displacement to obtain the actual riveting value; Based on the difference between the target riveting value and the actual riveting value, adjust the riveting distance of the pressure head and / or adjust the downward speed of the pressure head.

8. The riveting control method according to claim 4, characterized in that, The adjustment of at least one riveting process parameter corresponding to the target riveting process based on the size parameters includes: Based on the thickness of the connected parts, the target clamping force of the riveting tool is adjusted during the pre-pressing stage.

9. The riveting control method according to claim 1, characterized in that, The method further includes: If the dimensional parameters exceed the preset parameter range, an alarm will be issued and the target riveting process will be stopped.

10. A riveting control device, characterized in that, include: The receiving module is used to receive pre-compression process data corresponding to the target riveting process, wherein the target riveting process is under load, and the pre-compression process data is used to characterize the force state, displacement state, or at least the relationship between the two of the riveting tool in the pre-compression stage. The feature position determination module is used to determine at least one feature position for characterizing the preset mechanical state of the riveting tool based on the pre-compression process data. A size determination module is used to determine the size parameters of at least one riveting object based on the positional relationship between the feature position and the reference position, wherein the reference position is obtained based on an empty riveting operation under no load, and the riveting object includes at least a rivet and / or a connected part. An adjustment module is used to adjust at least one riveting process parameter corresponding to the target riveting process based on the size parameters.

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