A method and system for controlling a mold product manufacturing process

Abstract

The present application relates to the technical field of process control, in particular to a mold product manufacturing process control method and system, comprising the following steps: obtaining a machining surface actual position and a curved surface theoretical model, determining a theoretical position and a normal deviation amount, correlating a normal vector and a principal curvature to form a local geometric state amount, determining a compensation effective position and a predicted path section according to a tool movement progress, a feed speed and a process time consumption, comparing path local geometric state amounts, determining a crossing position and dividing a sub-section and a correction section boundary when a geometric state crossing occurs, calculating a normal correction amount according to a crossing determination result, the normal deviation amount, the sub-section local geometric state amount and tool geometric parameters, and adjusting the correction amount and the machining path according to a tool real-time position. In the present application, the path local geometric state is distinguished and the correction amount is configured, so that the compensation is matched with the path geometric change, and the normal correction continuously changes with the tool section position.

Description

Technical Field

[0001] This invention relates to the field of process control technology, and in particular to a method and system for controlling the manufacturing process of mold products. Background Technology

[0002] The field of process control technology mainly involves the acquisition, transmission, calculation, judgment, and control of the operating status, process parameters, position status, and execution objects during production or processing. It typically acquires process data through sensors, measuring devices, controllers, and actuators, and adjusts the operation of the execution objects based on set parameters, status feedback, and control commands. Traditional mold manufacturing process control methods involve comparing machining surface measurement data with a surface theory model to obtain machining deviations. These deviations are then combined with the CNC machining path, tool position, feed rate, and tool geometry parameters to determine the corresponding machining position. The CNC system generates compensation commands based on the machining deviations and preset compensation rules. As the tool moves along the machining path, the tool machining path is adjusted according to the real-time position, machining parameters, and compensation commands.

[0003] Traditional mold processing relies on comparing the measured surface of the machined surface with the theoretical model of the curved surface to determine the position of the deviation, and combining the CNC machining path, tool position, feed rate and tool geometry parameters to determine the corresponding position of the deviation. The compensation process is mostly applied to the subsequent tool path according to the predetermined deviation value and preset rules. When the machining path crosses the local geometric state change area of ​​the curved surface, there is no corresponding relationship between the single position deviation and the subsequent different curved surface states. When the compensation amount is applied along the path, the correction boundary is prone to be inconsistent with the actual geometric change, making it difficult to match the path correction basis for different local curved surface states. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the existing technology and to propose a method and system for controlling the manufacturing process of mold products.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: a method for controlling the manufacturing process of mold products, comprising the following steps: S1: Obtain the measured position of the processed surface of the mold product as the measurement position and the corresponding surface theoretical model. Determine the corresponding theoretical position according to the correspondence between the measurement position and the surface theoretical model. Obtain the normal deviation amount according to the deviation between the measurement position and the theoretical position along the surface normal at the theoretical position. Extract the normal vector and principal curvature of the theoretical position and associate them with the measurement position to obtain the local geometric state quantity of the measurement position. S2: Obtain tool movement progress, tool feed rate, process time and machining path information; determine the effective path position of the tool when the normal deviation compensation takes effect based on the tool movement progress, tool feed rate and process time; determine the expected effective path segment along the machining path information with the effective path position as the starting point. S3: Based on the expected effective path segment and the surface theory model, extract the local geometric state quantities of each path position, compare them with the measured local geometric state quantities to determine the crossing judgment result, determine the crossing position when a geometric crossing occurs, and divide the expected effective path segment into multiple sub-segments according to the crossing position. Based on the local geometric state quantities of each path position, obtain the local geometric state quantities of each sub-segment corresponding to each sub-segment, and use each sub-segment obtained or the expected effective path segment that has not experienced a geometric crossing as a correction segment to determine the spatial boundary of each correction segment. S4: Obtain tool geometry parameters. When the crossing determination result is that no geometric crossing has occurred, determine the normal correction amount of the correction section based on the normal deviation amount. When the crossing determination result is that a geometric crossing has occurred, extract the geometry-independent deviation component from the normal deviation amount. Calculate the normal correction amount of each correction section based on the geometry-independent deviation component, the local geometric state quantity of the sub-section, and the tool geometry parameters. S5: Establish a correlation between the normal correction amount and the spatial boundary of each correction segment according to the corresponding correction segment, obtain the real-time position of the tool and compare it with the spatial boundary of each correction segment, apply the normal correction amount associated with the corresponding correction segment when the tool enters the correction segment, release the applied normal correction amount when the tool leaves the correction segment, continuously adjust the normal correction amount and adjust the tool processing path according to the position of the tool in the spatial boundary of the correction segment, and process the mold product.

[0006] As a further aspect of the present invention, the process of S1 is specifically as follows: S101: Controls the contact probe to contact the machining surface, reads the machine tool coordinates when the probe is triggered to obtain the actual measured position of the machining surface as the measurement position, reads the surface theoretical model in the CNC machining data, and determines the surface position according to the coordinate correspondence of the measurement position in the surface theoretical model to obtain the theoretical position; S102: Read the normal vector in the surface theoretical model according to the theoretical position, and calculate the normal deviation amount according to the position deviation between the measured position and the theoretical position along the normal vector direction; S103: Read the principal curvature in the surface theoretical model according to the theoretical position, associate the normal vector and principal curvature with the measurement position, and obtain the local geometric state quantity of the measurement position.

[0007] As a further aspect of the present invention, the process of S2 is specifically as follows: S201: Read the tool movement progress and tool feed rate in the CNC running state, read the CNC machining code to obtain machining path information, read the timing record of measurement trigger and compensation response, and obtain the process time; S202: Calculate the path advance distance of the tool within the corresponding time range based on the tool feed rate and the process time, determine the position reached by the tool along the machining path information based on the tool movement progress and path advance distance, and obtain the effective path position; S203: Locate the corresponding program segment in the processing path information according to the effective path location, read the path range corresponding to the program segment, and obtain the expected effective path segment; S204: Read the start and end positions of the path range according to the expected effective path segment, and map the start and end positions to the spatial coordinates in the processing path information to obtain the spatial boundary of the expected effective path segment. The spatial boundary of the expected effective path segment is used to determine the spatial boundary of the correction segment.

[0008] As a further aspect of the present invention, the process for obtaining the process time is specifically as follows: Read the start and end timing records of measurement actions, data transmission, compensation calculation, interpolation waiting, and servo response. Determine the time consumed by measurement actions, data transmission, compensation calculation, interpolation waiting, and servo response based on each timing record. Calculate the total time consumed by the process based on the time consumed by measurement actions, data transmission, compensation calculation, interpolation waiting, and servo response.

[0009] As a further aspect of the present invention, the process of S3 is specifically as follows: S301: Determine multiple path locations based on the expected effective path segment, read the normal vector and principal curvature corresponding to each path location in the surface theory model, and obtain the local geometric state quantities of each path location; S302: Compare the normal vector and principal curvature in the local geometric state quantities of each path position with the normal vector and principal curvature in the local geometric state quantities of the measurement position, respectively, to obtain the path position geometric comparison result, and determine whether the geometric state has crossed based on the path position geometric comparison result, to obtain the crossing determination result; S303: When the crossing determination result is that a geometric crossing has occurred, the path position where the normal relationship or principal curvature changes is determined based on the path position geometric comparison result, and the crossing position is obtained. S304: Determine the segment division state based on the crossing determination result. When a geometric crossing occurs, divide the expected effective path segment into multiple sub-segments according to the crossing position. Obtain the local geometric state quantity of each sub-segment based on the normal vector and principal curvature of the path position located in each sub-segment in the local geometric state quantity of each path position. Use each sub-segment obtained or the expected effective path segment that has not undergone geometric crossing as a correction segment. Record the spatial coordinates corresponding to the start and end positions of each correction segment to obtain the spatial boundary of each correction segment.

[0010] As a further aspect of the present invention, the process for determining the crossing determination result is specifically as follows: The included normal angle is calculated based on the normal vector of each path position and the normal vector in the local geometric state quantity of the measurement position. The principal curvature difference ratio is calculated based on the principal curvature of each path position and the corresponding principal curvature in the local geometric state quantity of the measurement position, and the sign change state of the corresponding principal curvature is determined. The included normal angle is compared with a preset normal deflection threshold, and the principal curvature difference ratio is compared with a preset curvature change threshold. When the included normal angle reaches the preset normal deflection threshold, the principal curvature difference ratio reaches the preset curvature change threshold, or the sign of the corresponding principal curvature is reversed, it is determined that a geometric state crossing has occurred at the corresponding path position, and the crossing determination result is obtained.

[0011] As a further aspect of the present invention, the process of S4 is specifically as follows: S401: Read the tool radius and tool length parameters from the CNC tool parameter record to obtain the tool geometry parameters; S402: When the crossing determination result is that no geometric crossing has occurred, the correction value of the correction segment along the normal direction of the surface is determined according to the normal deviation amount, and the normal correction amount of the uncrossed segment is generated. When the crossing determination result is that a geometric crossing has occurred, the cutting layer thickness deviation corresponding to the measurement position is calculated based on the principal curvature in the local geometric state quantity of the measurement position, the tool geometric parameters, and the normal deviation. The deviation part that is unrelated to the local geometric state change is extracted based on the cutting layer thickness deviation to obtain the geometrically unrelated deviation component. S403: Determine the contact geometry relationship between the tool and the surface based on the principal curvature and normal vector in the local geometric state of the sub-segment and the tool geometry parameters. Calculate the normal correction amount for the crossed segment based on the geometrically independent deviation component and the contact geometry relationship. Select the normal correction amount for the uncrossed segment or the crossed segment based on the crossing determination result to obtain the normal correction amount.

[0012] As a further aspect of the present invention, the process for determining the normal correction amount across the segment is specifically as follows: The local radius of curvature and the sign of curvature are determined based on the principal curvature in the local geometric state quantities of the sub-segment. The convex or concave state of the corresponding sub-segment is determined based on the sign of curvature. The contact geometry between the tool and the surface is determined based on the tool radius and the local radius of curvature in the tool geometry parameters. The normal displacement of the corresponding sub-segment is determined based on the geometrically independent deviation component and the contact geometry. The normal correction direction is determined based on the normal vector in the local geometric state quantities of the sub-segment and the deviation direction of the geometrically independent deviation component. The normal correction amount of the spanning segment is obtained based on the normal displacement and the normal correction direction.

[0013] As a further aspect of the present invention, the process of S5 is specifically as follows: S501: Establish a connection between the normal correction amount and the spatial boundary of each correction segment according to the corresponding correction segment, record the correction value and spatial boundary of each correction segment, and obtain the segment correction record. S502: Read the tool interpolation coordinates during CNC machining, obtain the real-time position of the tool, compare the real-time position of the tool with the spatial boundary of each correction segment according to the segment correction record, determine the correction segment that the tool is currently entering or leaving, and obtain the segment position status. S503: According to the segment position status, when the tool enters the correction segment, the normal correction amount corresponding to the correction segment entered in the segment correction record is applied. When the tool leaves the correction segment, the applied normal correction amount is released. The ratio of the path travel from the real-time position of the tool to the starting position of the correction segment to the preset transition travel is determined to obtain the correction transition ratio. Linear interpolation is performed between the correction value corresponding to the previous correction segment and the correction value corresponding to the current correction segment according to the correction transition ratio. When there is no correction segment before the current correction segment, the zero value is used as the correction value corresponding to the previous correction segment. After the correction transition ratio reaches the set upper limit value, the correction value corresponding to the current correction segment is taken to obtain the adjusted normal correction amount. S504: Correct the current interpolation position of the tool according to the adjusted normal correction amount, generate the tool machining path, and control the machine tool servo axis to drive the tool to cut the mold product according to the tool machining path.

[0014] A mold product manufacturing process control system, wherein the mold product manufacturing process control system is used to execute the above-described mold product manufacturing process control method, the system comprising: Measured geometric state extraction module: Obtain the measured position of the processed surface of the mold product as the measurement position and the corresponding surface theoretical model of the processed surface. Determine the corresponding theoretical position according to the correspondence between the measured position and the surface theoretical model. Obtain the normal deviation amount according to the deviation between the measured position and the theoretical position along the surface normal at the theoretical position. Extract the normal vector and principal curvature of the theoretical position and associate them with the measured position to obtain the local geometric state quantity of the measured position. Effective path segment prediction module: acquires tool movement progress, tool feed rate, process time and machining path information, determines the effective path position reached by the tool when the normal deviation compensation takes effect based on the tool movement progress, tool feed rate and process time, and determines the expected effective path segment along the machining path information with the effective path position as the starting point; State comparison and partitioning module: Based on the expected effective path segment and surface theory model, extract the local geometric state quantities of each path position, compare them with the local geometric state quantities of the measured position to determine the crossing judgment result, determine the crossing position when a geometric state crossing occurs, and divide the expected effective path segment into multiple sub-segments according to the crossing position. Based on the local geometric state quantities of each path position, obtain the local geometric state quantities of each sub-segment corresponding to the sub-segment, and use each sub-segment obtained or the expected effective path segment that has not experienced a geometric state crossing as a correction segment to determine the spatial boundary of each correction segment; Normal correction calculation module: acquires tool geometry parameters; when the crossing determination result is that no geometric crossing has occurred, determines the normal correction amount of the correction section based on the normal deviation amount; when the crossing determination result is that a geometric crossing has occurred, extracts the geometry-independent deviation component from the normal deviation amount; and calculates the normal correction amount of each correction section based on the geometry-independent deviation component, the local geometric state quantity of the sub-section, and the tool geometry parameters. Real-time path correction execution module: It establishes an association between the normal correction amount and the spatial boundary of each correction segment according to the corresponding correction segment, obtains the real-time position of the tool and compares it with the spatial boundary of each correction segment, applies the normal correction amount associated with the corresponding correction segment when the tool enters the correction segment, and releases the applied normal correction amount when the tool leaves the correction segment. It continuously adjusts the normal correction amount and the tool processing path according to the position of the tool in the spatial boundary of the correction segment, and processes the mold product.

[0015] Compared with the prior art, the advantages and positive effects of the present invention are as follows: In this invention, a local geometric state quantity is formed by correlating the normal deviation of the measured position with the normal vector and principal curvature of the theoretical position. The compensation effective position and the expected effective path segment are determined based on the tool movement progress, feed rate, and process time, ensuring that the deviation compensation corresponds to the actual effective path. Further comparison of the local geometric state between the path position and the measured position is made. When a geometric state crossing occurs, sub-segments are divided, and the normal correction amount is calculated by combining the geometrically independent deviation component, the local geometric state quantity of the sub-segment, and the tool geometric parameters, ensuring that different geometric states correspond to independent correction bases. By continuously adjusting the normal correction amount based on the spatial boundary of the correction segment and the real-time tool position, the path correction can be seamlessly integrated with changes in segment position. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the mold product manufacturing process control method of the present invention; Figure 2 This is a schematic diagram of the mold product manufacturing process control workflow of the present invention; Figure 3 This is a schematic diagram of the geometric state crossing determination principle of the present invention; Figure 4 This is a schematic diagram illustrating the principle of the cross-segment normal correction amount of the present invention; Figure 5 This is a schematic diagram of the mold product manufacturing process control system of the present invention. Detailed Implementation

[0017] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0018] This embodiment provides a method for controlling the manufacturing process of mold products. This method establishes a continuous data stream based on the on-machine measurement results of the mold product's machined surface, the surface theoretical model, and the machining path being executed by the tool. During machining, the actual positional deviation of the machined surface is first restored to the surface normal direction, while simultaneously retaining the normal vector and principal curvature corresponding to the measurement position. Then, combining the tool movement progress, tool feed rate, and the time taken from measurement to actual compensation effectiveness, the path segment corresponding to when the deviation truly affects the tool is determined. Next, it is determined whether the local surface geometry within the expected effective path segment still maintains the same relationship as the measurement position. When the path passes through a location where the normal relationship or curvature state changes, the normal deviation obtained from the measurement position is not directly translated to the subsequent path. Instead, the deviation portion independent of the local geometry is extracted, and the normal correction amount is re-determined based on the curvature, normal, and tool geometry parameters of each correction segment. Finally, the correction amount is applied, deactivated, and continuously adjusted according to the relationship between the real-time tool position and the spatial boundaries of each correction segment, ensuring that the range of the correction effect corresponds to the current machining position.

[0019] Please see Figure 1 and Figure 2 S1: Obtain the measured position of the machined surface of the mold product as the measurement position, and simultaneously obtain the corresponding surface theoretical model. The measurement position belongs to the spatial position data in the current machining coordinate system, originating from the on-machine contact measurement process; the surface theoretical model belongs to the position and geometric information in the CNC machining data used to describe the theoretical shape of the surface to be machined. Corresponding the measurement position to the surface theoretical model with coordinates is to place the actual measurement result onto the corresponding position on the theoretical surface, giving the deviation of the measured position a clear theoretical reference. After completing the correspondence, the theoretical position of the measurement position in the surface theoretical model is determined, and the surface normal at the theoretical position is used as the deviation decomposition direction. The deviation of the measurement position relative to the theoretical position along this normal direction is determined as the normal deviation. The normal deviation represents the positional offset of the actual machined surface relative to the theoretical surface in the local normal direction, without mixing tangential position differences into subsequent normal compensation.

[0020] After obtaining the theoretical position, the normal vector and principal curvature corresponding to the theoretical position are read from the surface theory model. The normal vector describes the local orientation of the theoretical surface at that position, and the principal curvature describes the local bending state of the theoretical surface in different principal directions. A correspondence is established between the normal vector and principal curvature and the measurement position to form the local geometric state quantity of the measurement position. The local geometric state quantity of the measurement position is not a single deviation value, but rather a stored local surface orientation and curvature information corresponding to the measurement position. Its function is to provide a comparison benchmark for subsequent judgments on whether the predicted effective path passes through different geometric states. Therefore, S1 outputs the normal deviation and the local geometric state quantity of the measurement position, and passes them respectively to the subsequent path prediction, geometric state comparison, and normal correction determination processes.

[0021] S101: Controls the contact between the machine-contact probe and the machined surface of the mold product, and reads the machine coordinates corresponding to the probe trigger. Probe triggering indicates that the probe has contacted the machined surface in the current measurement action; therefore, the machine coordinates at the time of triggering can be used as the actual measured position of the machined surface and recorded as the measurement position. Subsequently, the surface theory model in the current CNC machining data is read, and the measurement position is mapped to the surface theory model using the current machining coordinate relationship. The surface position corresponding to the measurement position is determined in the model and used as the theoretical position. During the coordinate mapping process, the consistency between the machining coordinates used for measurement and the machining coordinates on which the surface theory model is based is maintained, so that the subsequently obtained theoretical normals and principal curvatures can correspond to the actual measurement points. When the probe trigger record is missing, the trigger coordinates cannot be read, or the measurement coordinates cannot establish a correspondence with the surface theory model, the measurement result will not be entered into subsequent deviation processing, and the currently unused measurement state will continue to be retained until a measurement position that corresponds to the surface theory model is obtained.

[0022] S102: The normal vector of the surface theoretical model at the theoretical position is read, and this normal vector is used to define the spatial components that need correction between the measured and theoretical positions. Specifically, the spatial deviation direction from the theoretical to the measured position is first determined, and then the corresponding part of this deviation in the normal direction of the theoretical position is extracted. The magnitude and direction of the deviation along the normal direction are used together as the normal deviation. This normal deviation only describes the local normal deviation of the actual surface relative to the theoretical surface. Subsequently, it is not necessary to use the entire spatial displacement between the measured and theoretical positions to directly modify the toolpath, thus maintaining the connection between the correction direction and the local orientation of the surface theoretical model in the corresponding region of the measured position. After the normal deviation is generated, it is correlated with the measured position and transmitted to the path effective position prediction and correction amount determination process.

[0023] S103: Based on the theoretical position, continue reading the principal curvature from the surface theoretical model and associate this principal curvature with the already obtained normal vector to the measurement position, forming a local geometric state quantity for the measurement position. This local geometric state quantity describes the local geometric state of the theoretical surface corresponding to the measurement position. The normal vector distinguishes changes in surface orientation, and the principal curvature distinguishes changes in the degree and nature of surface curvature. Subsequently, the same type of local geometric state quantity is obtained for the expected effective path segment and compared with the local geometric state quantity of the measurement position according to the normal vector and principal curvature, respectively. Therefore, the local geometric state quantity of the measurement position constitutes a unified comparison benchmark for subsequent crossing determination.

[0024] Please see Figure 1 and Figure 2 S2: Acquire the tool movement progress, tool feed rate, process time, and machining path information during the current CNC machining process. Tool movement progress indicates the current position of the tool within the machining path. Tool feed rate indicates the tool's movement along the current machining path. Machining path information comes from the currently executing CNC machining code and describes the path range the tool will subsequently traverse. Process time represents the time elapsed from the occurrence of the measurement action to the actual effect of the corresponding compensation on the tool movement through data processing, interpolation waiting, and servo response. Since the tool continues to move along the machining path during this time, the measured position cannot be directly taken as the compensation effective position. It is necessary to predict the position the tool has reached when the compensation actually takes effect based on the tool's path progression during the process time.

[0025] The current path reference is determined based on the tool movement progress. Then, the corresponding path advancement distance during this time period is determined based on the tool feed rate and process time. This path advancement distance is then mapped forward along the machining path information from the current movement progress, thus obtaining the effective path position. The effective path position represents the position of the tool on the machining path when the normal correction information formed by the current measurement results completes the entire response process. Subsequently, based on the machining program segment where this position is located, the path range corresponding to this program segment is determined, forming the expected effective path segment. The expected effective path segment is used to limit the scope of subsequent geometric state judgment and correction, avoiding the indiscriminate application of deviations obtained at one measurement position to other path positions unrelated to the current effective process.

[0026] S201: Reads the tool movement progress and tool feed rate from the CNC operating status, and reads the machining path information from the currently executing CNC machining code. Simultaneously, it reads the timing records formed between measurement triggers and compensation responses, using these records to determine the process time. The timing records are obtained according to the sequence of measurement actions, data transmission, compensation calculations, interpolation waiting, and servo responses within the same compensation processing chain. The time consumed at each stage collectively describes the time span from when surface information is measured to when the correction result is actually incorporated into the tool movement response. Each timing record originates from the start and end records of its corresponding processing stage. After reading, it is assigned according to its corresponding processing stage, and then sequentially forms the measurement action time, data transmission time, compensation calculation time, interpolation waiting time, and servo response time, thus forming the process time. If the start and end records of a certain processing stage cannot form a complete correspondence, the process time for that stage is not used as the basis for effective path prediction, avoiding the misinterpretation of a missing response process as completed.

[0027] S202: Determine the path distance the tool will continue to advance along the machining path within the corresponding time period based on the tool feed rate and process time. This process does not change the tool movement progress, but rather incorporates the tool movement that has already occurred during the compensation response into the position prediction. Subsequently, starting from the read tool movement progress, the tool's final position is determined according to the machining path information and the path progression relationship, and this position is defined as the effective path position. The effective path position thus formed is affected by both the current path progress and the compensation response time. When the process experienced by the compensation response changes, the effective position is still re-associated with the actual tool path according to the corresponding process time.

[0028] S203: Locate the corresponding CNC program segment in the machining path information using the effective path location, and read the path range corresponding to that program segment. This path range, based on the positional relationship of the effective path location, represents the subsequent machining path that can be corresponding to the current compensation response, and serves as the expected effective path segment. The expected effective path segment is then passed to the local geometry extraction process, used to read the local normal and principal curvature of different path positions within this segment from the surface theory model, ensuring that subsequent crossing judgments are only performed on the path range that the compensation will actually affect.

[0029] S204: Based on the expected effective path segment, read the start and end positions of the corresponding path range, and map the start and end positions to spatial coordinates in the processing path information to form the spatial boundary of the expected effective path segment. The spatial boundary is used to represent the entry and exit positions of the path segment in the actual processing coordinates. When the expected effective path segment is geometrically crossed, the spatial boundary is further subdivided into the spatial boundaries of each correction segment based on the crossing position; when no crossing occurs, the start and end positions of the expected effective path segment are directly used as the boundary basis for the corresponding correction segment.

[0030] Please see Figure 1 , Figure 2 and Figure 3 S3: Based on the expected effective path segment and the surface theoretical model, extract the local geometric state quantities of each path location distributed along the segment, and compare them with the local geometric state quantities of the measured location. The local geometric state quantities of each path location and the local geometric state quantities of the measured location formed in S1 use the same type of information, namely the normal vector and principal curvature of the theoretical surface corresponding to the path location. Therefore, it is possible to determine whether the expected effective path is still in the same local surface state as the measured location under a unified geometric meaning.

[0031] During the comparison process, the direction change of the path position normal vector relative to the measurement position normal vector, as well as the degree and sign of the change of the corresponding principal curvature relative to the measurement position principal curvature, are checked. A change in the normal relationship indicates a change in the local orientation of the surface; a change in the principal curvature indicates a change in the local bending relationship; and a reversal of the principal curvature sign further indicates a change in the bending properties of the corresponding surface. When the above geometric relationships reach the preset crossing judgment conditions, a geometric state crossing is determined at the corresponding path position. Preset normal deflection thresholds and preset curvature change thresholds are determined as the geometric state judgment conditions for the current processing task before this comparison is performed, and are invoked as the judgment boundaries for normal and curvature changes, respectively, during the comparison process. Their function is to convert continuously changing normal and curvature relationships into a state judgment of whether a correction relationship needs to be redefined, without changing the data of the surface theoretical model itself.

[0032] When a geometric state crossing occurs, the crossing position where the normal relationship or principal curvature state changes is determined based on the geometric comparison results of the path position. The expected effective path segment is then divided into multiple sub-segments according to the crossing position. Subsequently, local geometric state quantities for each sub-segment are formed based on the normal vector and principal curvature corresponding to the path position within that sub-segment, ensuring that each sub-segment has geometric information corresponding to its own surface state. The resulting sub-segments serve as correction segments. When no geometric state crossing occurs, sub-segment division is not performed; the expected effective path segment is directly used as a correction segment. Each correction segment records the spatial coordinates of its corresponding start and end positions, forming a spatial boundary. The correction segment, its corresponding local geometric state quantity, and the spatial boundary are then passed to the normal correction quantity determination process and the real-time path correction process.

[0033] S301: Based on the expected effective path segment, determine multiple path positions distributed along that segment, and read the normal vector and principal curvature corresponding to each path position from the surface theory model to form local geometric state quantities for each path position. The path positions come from the expected effective path segment itself, without introducing additional positions unrelated to the machining path. During reading, the path positions are mapped onto the surface theory model along the machining path correspondence, ensuring that the obtained normal vector and principal curvature always correspond to the positions the tool is expected to pass through. The resulting local geometric state quantities for each path position are then passed to the subsequent comparison process in path order.

[0034] S302: Compare the normal vectors in the local geometric state variables of each path location with the normal vectors in the local geometric state variables of the measurement location. Simultaneously, compare the principal curvatures of each path location with the corresponding principal curvatures of the measurement location to obtain the geometric comparison results for the path locations. For the normal vectors, determine the included normal angle based on their directional relationship and compare it with a preset normal deflection threshold. For the principal curvatures, form a principal curvature difference ratio based on the relative differences between corresponding principal curvatures, and simultaneously check whether the sign of the corresponding principal curvatures has reversed. Then compare the principal curvature difference ratio with a preset curvature change threshold. When the included normal angle reaches the preset normal deflection threshold, the principal curvature difference ratio reaches the preset curvature change threshold, or the sign of the corresponding principal curvature reverses, the corresponding path location is determined to have experienced a geometric state crossing, thus obtaining the crossing determination result. The three determination conditions correspond to changes in surface orientation, changes in curvature degree, and changes in curvature properties, respectively. When any relationship has changed to the determination boundary, the original geometric relationship of the measurement location will no longer be directly used subsequently.

[0035] S303: When the crossing determination result indicates a geometric crossing has occurred, the geometric comparison results of the path positions are checked sequentially along the expected effective path segment to determine the location where the normal relationship or principal curvature meets the crossing condition, and this path location is designated as the crossing position. The crossing position is used to divide the path range where compensation will take effect into continuous segments with different local geometric states. If different geometric state changes occur consecutively within the same expected effective path segment, corresponding segment boundaries are formed according to the order of each crossing position in the processing path, so that each subsequent sub-segment can establish a correspondence with its internal local geometric state.

[0036] S304: Determine the segment division state based on the crossing judgment result. When a geometric crossing occurs, the expected effective path segment is divided into multiple sub-segments according to the machining path sequence based on the crossing position. Then, the normal vector and principal curvature within the corresponding sub-segment are extracted from the local geometric state quantities of each path position, and the local geometric state quantities of each sub-segment are formed accordingly. The local geometric state quantities of the sub-segment retain the normal and curvature information used by the sub-segment to determine the contact relationship between the tool and the surface, and are transferred to the process of determining the normal correction amount of the crossing segment. Each sub-segment obtained is used as a correction segment. When no geometric crossing occurs, the complete expected effective path segment is used as the correction segment. Subsequently, the spatial coordinates corresponding to the start and end positions of each correction segment are recorded to obtain the spatial boundary of each correction segment, and each spatial boundary is kept associated with the corresponding correction segment. When the path position cannot obtain the corresponding normal vector or principal curvature in the surface theory model, the position does not enter the crossing judgment, and the relevant segment continues to remain in the state of incomplete geometric state confirmation until the surface theory information corresponding to the path position can be obtained.

[0037] Please see Figure 1 , Figure 2 and Figure 4 S4: Obtain the tool geometry parameters and select a normal correction method that is compatible with the current geometric state of the correction section based on the crossing determination result. The tool geometry parameters are derived from the tool parameter records used in the current CNC machining, including the tool radius and tool length parameters used to describe the tool size relationship. The tool geometry parameters and the principal curvature of the surface together determine the contact geometry relationship between the tool and the local surface. Therefore, when the expected effective path crosses different surface geometry states, it is necessary to process the deviation obtained from the measurement position and the local contact geometry relationship separately.

[0038] When the crossing determination result indicates that no geometric crossing has occurred, the expected effective path segment will still maintain the local geometric state relationship corresponding to the measurement position. Therefore, the correction amount along the normal direction of the surface is directly determined based on the normal deviation. When the crossing determination result indicates that a geometric crossing has occurred, the normal deviation of the measurement position is not directly used as the correction amount for all sub-segments. Instead, the cutting layer thickness deviation corresponding to the measurement position is first determined based on the local geometric state of the measurement position, tool geometry parameters, and normal deviation. Then, the deviation portion that does not change with the local geometric state is separated from this deviation, forming a geometrically independent deviation component. The geometrically independent deviation component represents the machining deviation content that needs to be corrected by subsequent sub-segments. It is separated from the contact geometry transformation relationship caused by the specific curvature at the measurement position, and therefore can serve as a common input for re-establishing the normal correction relationship between different local surface states.

[0039] For each sub-segment where a geometric state crossing occurs, the contact geometry between the tool and the corresponding surface of that sub-segment is determined based on the principal curvature and normal vector in the local geometric state quantities of the sub-segment, as well as the tool's geometric parameters. Then, based on the geometrically independent deviation component and this contact geometry, the required normal displacement to be applied under the current local surface state is determined in reverse. Simultaneously, the normal correction direction is determined based on the sub-segment normal vector and the deviation direction, thus forming the normal correction amount for each crossed segment corresponding to the correction segment. In this way, the same measurement deviation, after crossing a geometric state, no longer maintains the same normal displacement representation, but instead retains the same geometrically independent deviation content and is reconverted into the corresponding normal correction amount according to the contact geometry of each sub-segment.

[0040] S401: Read the tool parameter record currently used in CNC machining, obtain the tool radius and tool length parameters, and use them as tool geometry parameters. The tool geometry parameters must correspond to the currently used tool. They are then used in conjunction with the local curvature and normal relationships provided by the surface theory model to determine the contact geometry between the tool and the surface. If the tool parameter record does not correspond to the currently machining tool, the record will not be used for cross-segment correction conversion to avoid bringing the geometry of other tools into the current compensation process.

[0041] S402: When the crossing determination result is that no geometric crossing has occurred, the correction value of the correction segment along the normal direction of the surface is determined based on the normal deviation, and the normal correction amount of the uncrossed segment is generated. Since the local geometric state of this correction segment has not crossed the set geometric state determination conditions, the normal deviation obtained at the measurement position still maintains the same geometric correspondence with the expected effective path segment, and the normal deviation can be directly used as the basis for determining the correction direction and correction degree of this segment.

[0042] When the crossing determination result indicates a geometric crossing, the cutting layer thickness deviation corresponding to the measurement position is first determined based on the principal curvature, tool geometry parameters, and normal deviation in the local geometric state quantities at the measurement position. Here, the cutting layer thickness deviation represents the deviation of the actual surface from the cutting layer relationship under the contact conditions jointly formed by the local curvature at the measurement position and the current tool geometry. Subsequently, the deviation portion independent of changes in the local geometric state at the measurement position is extracted from the cutting layer thickness deviation to form a geometry-independent deviation component. This process first separates the curvature and tool contact relationship specific to the measurement position from the deviation representation, enabling the subsequent establishment of a new normal displacement relationship by recombining the local curvature in each sub-segment, rather than replicating the geometric transformation relationship specific to the measurement position to other surface states.

[0043] S403: Based on the principal curvatures in the local geometric state quantities of the sub-segment, determine the curvature radius relationship and curvature sign of the corresponding local surface, and use the curvature sign to distinguish between the convex and concave states of the corresponding sub-segment. Then, combining the tool radius and this local curvature relationship, determine the contact geometry between the tool and the surface in the corresponding surface state. The contact geometry describes the contact transformation relationship between the tool surface and the local surface, formed by the tool size and the surface curvature state, and is used to reconvert the same geometrically independent deviation component into the normal displacement required for the current sub-segment.

[0044] The normal displacement of a sub-segment is determined based on the geometrically independent deviation components and the corresponding contact geometry. Then, the normal correction direction is determined based on the deviation direction between the normal vector in the local geometric state quantities of the sub-segment and the geometrically independent deviation components. The normal displacement and the normal correction direction together form the normal correction amount for the crossed segment. Finally, based on the crossed segment determination result, the result corresponding to the current correction segment is selected from the normal correction amounts of the uncrossed segment and the crossed segment to obtain the normal correction amount. Each normal correction amount is then transmitted to the real-time path correction process of the corresponding correction segment.

[0045] Please see Figure 1 and Figure 2 S5: Associate each normal correction amount with the spatial boundary of each correction segment according to the corresponding correction segment, ensuring that each correction amount has a clearly defined path range. Subsequently, continuously acquire the real-time tool position during CNC machining and compare it with the spatial boundary of each correction segment to determine which correction segment the tool is currently in, whether it has just entered the correction segment, or whether it has already left the correction segment. This position determination connects the spatial segment obtained in S3 and the normal correction amount obtained in S4 to the actual tool movement process, ensuring that the correction amount only acts on the machining path after the tool enters the corresponding spatial range.

[0046] When the tool enters the correction section, the normal correction amount associated with that section is read and applied; when the tool leaves the correction section, the normal correction amount already applied to that section is released. To avoid direct switching of correction values ​​between adjacent correction sections at spatial boundaries, the correction transition ratio is determined based on the tool's real-time position relative to the starting position of the current correction section, and continuous linear interpolation is performed between the correction value corresponding to the previous correction section and the correction value corresponding to the current correction section. If there is no correction section before the current correction section, the uncorrected state is used as the transition starting point. As the tool continues to advance within the current correction section, the correction transition ratio changes according to the path travel, and the correction value corresponding to the current correction section is adopted after reaching the preset upper limit of the transition travel. This yields the adjusted normal correction amount, which is used to correct the tool's current interpolation position, forming an updated tool machining path. Subsequently, the tool continues to cut the mold product according to the updated tool machining path.

[0047] S501: Based on the established correspondence between each correction segment, associate the normal correction amount with the spatial boundary of the corresponding correction segment, and record the correction value, start position, and end position spatial boundary of each correction segment to form a segment correction record. The segment correction record saves the correction amount and correction range as the same correspondence. Subsequent real-time position comparison only needs to determine the correction segment where the tool is located to obtain the correction value corresponding to that segment. If a correction amount cannot be correlated with the established spatial boundary of the correction segment, then the correction amount will not be used as the real-time path correction input to avoid correction information without a clear range of action.

[0048] S502: Reads the tool interpolation coordinates during CNC machining and uses these coordinates as the real-time tool position. Based on the segment correction record, the real-time tool position is compared sequentially with the spatial boundaries of each correction segment. The tool's current position along the machining path is used to determine whether it has entered, is still in, or has left the corresponding correction segment, thus forming the segment position state. The segment position state is the trigger for real-time path correction, ensuring that the application and removal of the normal correction are driven by the actual tool path position, rather than solely by the completion of the correction calculation. If the real-time tool position reading fails or the current interpolation coordinates cannot establish a consistent positional relationship with the segment spatial boundary, the currently confirmed segment position state remains unchanged. The tool's real-time position is then updated only after acquiring a suitable tool position for boundary comparison.

[0049] S503: Control the application process of the corresponding normal correction amount according to the segment position status. When the tool enters the correction segment, the normal correction amount corresponding to the correction segment is obtained from the segment correction record; when the tool leaves the correction segment, the normal correction amount applied for leaving the segment is released. When the tool is inside the correction segment, a ratio relationship is established between the path travel formed along the machining path from the real-time tool position to the starting position of the correction segment and the preset transition travel to obtain the correction transition ratio. The preset transition travel is determined as the transition boundary condition of the current correction process before continuous adjustment is performed, and is used to define the path range for continuous transition from the previous correction state to the current segment correction state; an upper limit value is set to indicate that the continuous transition has been completed, and serves as the judgment condition for stopping the correction transition ratio from increasing further.

[0050] Within the transition range, linear interpolation is performed between the correction values ​​corresponding to the previous correction segment and the current correction segment according to the correction transition ratio. This ensures that the normal correction amount changes continuously according to the corresponding position as the tool moves along the path. When there is no correction segment before the current correction segment, a zero value indicates that no segment correction was applied previously, and this state serves as the transition starting point for the current correction segment. When the correction transition ratio reaches the set upper limit, the transition between the two segment correction values ​​stops, and the correction value corresponding to the current correction segment is adopted, thus obtaining the adjusted normal correction amount. This process ensures that the segment boundary serves as both the basis for switching correction states and distributes the changes in adjacent correction amounts across the continuous path range through the transition stroke.

[0051] S504: Based on the adjusted normal correction amount, the current interpolation position of the tool is corrected in the normal direction. This ensures that the interpolation position maintains the original machining path progression while incorporating the normal position adjustment corresponding to the current correction segment. The corrected interpolation position continuously forms the tool machining path. Subsequently, the machine tool servo axis is driven to cut the mold product according to the tool machining path. As the real-time tool position is continuously updated, the position judgment, continuous adjustment of correction amount, and interpolation position correction corresponding to S502 to S504 continue to be executed along with the machining path, ensuring that the current tool position, the spatial boundary of the correction segment, and the corresponding normal correction amount always remain associated in the same data chain. If the correction information fails to correspond to the current interpolation process during transmission, the state of not using this correction information is maintained until a consistent correspondence is established between the segment correction record, the real-time tool position, and the current interpolation position before proceeding with path correction.

[0052] Please see Figure 5A mold product manufacturing process control system includes a measured geometric state extraction module, an effective path segment prediction module, a state comparison and partitioning module, a normal correction calculation module, and a real-time path correction execution module. The measured geometric state extraction module (S1) is used to generate the normal deviation and the local geometric state of the measurement position; the effective path segment prediction module (S2) is used to determine the effective path position and the expected effective path segment; the state comparison and partitioning module (S3) is used to generate the crossing judgment result, the correction segment, and its spatial boundary; the normal correction calculation module (S4) is used to generate the normal correction amount corresponding to each correction segment based on the crossing state; and the real-time path correction execution module (S5) is used to apply, release, and continuously adjust the corresponding correction amount according to the real-time tool position, and generate the tool machining path based on the adjusted normal correction amount.

[0053] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention in any other way. Any person skilled in the art may make changes or modifications to the above-disclosed technical content to create equivalent embodiments that can be applied to other fields. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the protection scope of the present invention.

Claims

1. A method for controlling the manufacturing process of mold products, characterized in that, Includes the following steps: S1: Obtain the measured position of the processed surface of the mold product as the measurement position and the corresponding surface theoretical model. Determine the corresponding theoretical position according to the correspondence between the measurement position and the surface theoretical model. Obtain the normal deviation amount according to the deviation between the measurement position and the theoretical position along the surface normal at the theoretical position. Extract the normal vector and principal curvature of the theoretical position and associate them with the measurement position to obtain the local geometric state quantity of the measurement position. S2: Obtain tool movement progress, tool feed rate, process time and machining path information; determine the effective path position of the tool when the normal deviation compensation takes effect based on the tool movement progress, tool feed rate and process time; determine the expected effective path segment along the machining path information with the effective path position as the starting point. S3: Based on the expected effective path segment and the surface theory model, extract the local geometric state quantities of each path position, compare them with the measured local geometric state quantities to determine the crossing judgment result, determine the crossing position when a geometric crossing occurs, and divide the expected effective path segment into multiple sub-segments according to the crossing position. Based on the local geometric state quantities of each path position, obtain the local geometric state quantities of each sub-segment corresponding to each sub-segment, and use each sub-segment obtained or the expected effective path segment that has not experienced a geometric crossing as a correction segment to determine the spatial boundary of each correction segment. S4: Obtain tool geometry parameters. When the crossing determination result is that no geometric crossing has occurred, determine the normal correction amount of the correction section based on the normal deviation amount. When the crossing determination result is that a geometric crossing has occurred, extract the geometry-independent deviation component from the normal deviation amount. Calculate the normal correction amount of each correction section based on the geometry-independent deviation component, the local geometric state quantity of the sub-section, and the tool geometry parameters. S5: Establish a correlation between the normal correction amount and the spatial boundary of each correction segment according to the corresponding correction segment, obtain the real-time position of the tool and compare it with the spatial boundary of each correction segment, apply the normal correction amount associated with the corresponding correction segment when the tool enters the correction segment, release the applied normal correction amount when the tool leaves the correction segment, continuously adjust the normal correction amount and adjust the tool processing path according to the position of the tool in the spatial boundary of the correction segment, and process the mold product.

2. The method for controlling the manufacturing process of mold products according to claim 1, characterized in that, The process of S1 is as follows: S101: Controls the contact probe to contact the machining surface, reads the machine tool coordinates when the probe is triggered to obtain the actual measured position of the machining surface as the measurement position, reads the surface theoretical model in the CNC machining data, and determines the surface position according to the coordinate correspondence of the measurement position in the surface theoretical model to obtain the theoretical position; S102: Read the normal vector in the surface theoretical model according to the theoretical position, and calculate the normal deviation amount according to the position deviation between the measured position and the theoretical position along the normal vector direction; S103: Read the principal curvature in the surface theoretical model according to the theoretical position, associate the normal vector and principal curvature with the measurement position, and obtain the local geometric state quantity of the measurement position.

3. The method for controlling the manufacturing process of mold products according to claim 1, characterized in that, The process of S2 is as follows: S201: Read the tool movement progress and tool feed rate in the CNC running state, read the CNC machining code to obtain machining path information, read the timing record of measurement trigger and compensation response, and obtain the process time; S202: Calculate the path advance distance of the tool within the corresponding time range based on the tool feed rate and the process time, determine the position reached by the tool along the machining path information based on the tool movement progress and path advance distance, and obtain the effective path position; S203: Locate the corresponding program segment in the processing path information according to the effective path location, read the path range corresponding to the program segment, and obtain the expected effective path segment; S204: Read the start and end positions of the path range according to the expected effective path segment, and map the start and end positions to the spatial coordinates in the processing path information to obtain the spatial boundary of the expected effective path segment. The spatial boundary of the expected effective path segment is used to determine the spatial boundary of the correction segment.

4. The method for controlling the manufacturing process of mold products according to claim 3, characterized in that, The process of obtaining the time consumption of the process is as follows: Read the start and end timing records of measurement actions, data transmission, compensation calculation, interpolation waiting, and servo response. Determine the time consumed by measurement actions, data transmission, compensation calculation, interpolation waiting, and servo response based on each timing record. Calculate the total time consumed by the process based on the time consumed by measurement actions, data transmission, compensation calculation, interpolation waiting, and servo response.

5. The method for controlling the manufacturing process of mold products according to claim 1, characterized in that, The process of S3 is as follows: S301: Determine multiple path locations based on the expected effective path segment, read the normal vector and principal curvature corresponding to each path location in the surface theory model, and obtain the local geometric state quantities of each path location; S302: Compare the normal vector and principal curvature in the local geometric state quantities of each path position with the normal vector and principal curvature in the local geometric state quantities of the measurement position, respectively, to obtain the path position geometric comparison result, and determine whether the geometric state has crossed based on the path position geometric comparison result, to obtain the crossing determination result; S303: When the crossing determination result is that a geometric crossing has occurred, the path position where the normal relationship or principal curvature changes is determined based on the path position geometric comparison result, and the crossing position is obtained. S304: Determine the segment division state based on the crossing determination result. When a geometric crossing occurs, divide the expected effective path segment into multiple sub-segments according to the crossing position. Obtain the local geometric state quantity of each sub-segment based on the normal vector and principal curvature of the path position located in each sub-segment in the local geometric state quantity of each path position. Use each sub-segment obtained or the expected effective path segment that has not undergone geometric crossing as a correction segment. Record the spatial coordinates corresponding to the start and end positions of each correction segment to obtain the spatial boundary of each correction segment.

6. The method for controlling the manufacturing process of mold products according to claim 5, characterized in that, The process for determining the crossing result is as follows: The included normal angle is calculated based on the normal vector of each path position and the normal vector in the local geometric state quantity of the measurement position. The principal curvature difference ratio is calculated based on the principal curvature of each path position and the corresponding principal curvature in the local geometric state quantity of the measurement position, and the sign change state of the corresponding principal curvature is determined. The included normal angle is compared with a preset normal deflection threshold, and the principal curvature difference ratio is compared with a preset curvature change threshold. When the included normal angle reaches the preset normal deflection threshold, the principal curvature difference ratio reaches the preset curvature change threshold, or the sign of the corresponding principal curvature is reversed, it is determined that a geometric state crossing has occurred at the corresponding path position, and the crossing determination result is obtained.

7. The method for controlling the manufacturing process of mold products according to claim 1, characterized in that, The process of S4 is as follows: S401: Read the tool radius and tool length parameters from the CNC tool parameter record to obtain the tool geometry parameters; S402: When the crossing determination result is that no geometric crossing has occurred, the correction value of the correction segment along the normal direction of the surface is determined according to the normal deviation amount, and the normal correction amount of the uncrossed segment is generated. When the crossing determination result is that a geometric crossing has occurred, the cutting layer thickness deviation corresponding to the measurement position is calculated based on the principal curvature in the local geometric state quantity of the measurement position, the tool geometric parameters, and the normal deviation. The deviation part that is unrelated to the local geometric state change is extracted based on the cutting layer thickness deviation to obtain the geometrically unrelated deviation component. S403: Determine the contact geometry relationship between the tool and the surface based on the principal curvature and normal vector in the local geometric state of the sub-segment and the tool geometry parameters. Calculate the normal correction amount for the crossed segment based on the geometrically independent deviation component and the contact geometry relationship. Select the normal correction amount for the uncrossed segment or the crossed segment based on the crossing determination result to obtain the normal correction amount.

8. The method for controlling the manufacturing process of mold products according to claim 7, characterized in that, The process for determining the normal correction amount for the crossed section is as follows: The local radius of curvature and the sign of curvature are determined based on the principal curvature in the local geometric state quantities of the sub-segment. The convex or concave state of the corresponding sub-segment is determined based on the sign of curvature. The contact geometry between the tool and the surface is determined based on the tool radius and the local radius of curvature in the tool geometry parameters. The normal displacement of the corresponding sub-segment is determined based on the geometrically independent deviation component and the contact geometry. The normal correction direction is determined based on the normal vector in the local geometric state quantities of the sub-segment and the deviation direction of the geometrically independent deviation component. The normal correction amount of the spanning segment is obtained based on the normal displacement and the normal correction direction.

9. The method for controlling the manufacturing process of mold products according to claim 1, characterized in that, The process of S5 is as follows: S501: Establish a connection between the normal correction amount and the spatial boundary of each correction segment according to the corresponding correction segment, record the correction value and spatial boundary of each correction segment, and obtain the segment correction record. S502: Read the tool interpolation coordinates during CNC machining, obtain the real-time position of the tool, compare the real-time position of the tool with the spatial boundary of each correction segment according to the segment correction record, determine the correction segment that the tool is currently entering or leaving, and obtain the segment position status. S503: According to the segment position status, when the tool enters the correction segment, the normal correction amount corresponding to the correction segment entered in the segment correction record is applied. When the tool leaves the correction segment, the applied normal correction amount is released. The ratio of the path travel from the real-time position of the tool to the starting position of the correction segment to the preset transition travel is determined to obtain the correction transition ratio. Linear interpolation is performed between the correction value corresponding to the previous correction segment and the correction value corresponding to the current correction segment according to the correction transition ratio. When there is no correction segment before the current correction segment, the zero value is used as the correction value corresponding to the previous correction segment. After the correction transition ratio reaches the set upper limit value, the correction value corresponding to the current correction segment is taken to obtain the adjusted normal correction amount. S504: Correct the current interpolation position of the tool according to the adjusted normal correction amount, generate the tool machining path, and control the machine tool servo axis to drive the tool to cut the mold product according to the tool machining path.

10. A mold product manufacturing process control system, characterized in that, The system is used to implement the mold product manufacturing process control method as described in any one of claims 1-9, the system comprising: Measured geometric state extraction module: Obtain the measured position of the processed surface of the mold product as the measurement position and the corresponding surface theoretical model of the processed surface. Determine the corresponding theoretical position according to the correspondence between the measured position and the surface theoretical model. Obtain the normal deviation amount according to the deviation between the measured position and the theoretical position along the surface normal at the theoretical position. Extract the normal vector and principal curvature of the theoretical position and associate them with the measured position to obtain the local geometric state quantity of the measured position. Effective path segment prediction module: acquires tool movement progress, tool feed rate, process time and machining path information, determines the effective path position reached by the tool when the normal deviation compensation takes effect based on the tool movement progress, tool feed rate and process time, and determines the expected effective path segment along the machining path information with the effective path position as the starting point; State comparison and partitioning module: Based on the expected effective path segment and surface theory model, extract the local geometric state quantities of each path position, compare them with the local geometric state quantities of the measured position to determine the crossing judgment result, determine the crossing position when a geometric state crossing occurs, and divide the expected effective path segment into multiple sub-segments according to the crossing position. Based on the local geometric state quantities of each path position, obtain the local geometric state quantities of each sub-segment corresponding to the sub-segment, and use each sub-segment obtained or the expected effective path segment that has not experienced a geometric state crossing as a correction segment to determine the spatial boundary of each correction segment; Normal correction calculation module: acquires tool geometry parameters; when the crossing determination result is that no geometric crossing has occurred, determines the normal correction amount of the correction section based on the normal deviation amount; when the crossing determination result is that a geometric crossing has occurred, extracts the geometry-independent deviation component from the normal deviation amount; and calculates the normal correction amount of each correction section based on the geometry-independent deviation component, the local geometric state quantity of the sub-section, and the tool geometry parameters. Real-time path correction execution module: It establishes an association between the normal correction amount and the spatial boundary of each correction segment according to the corresponding correction segment, obtains the real-time position of the tool and compares it with the spatial boundary of each correction segment, applies the normal correction amount associated with the corresponding correction segment when the tool enters the correction segment, and releases the applied normal correction amount when the tool leaves the correction segment. It continuously adjusts the normal correction amount and the tool processing path according to the position of the tool in the spatial boundary of the correction segment, and processes the mold product.

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