Powder material 3d printing multi-jet fusion control system

Abstract

The application discloses a powder material 3D printing multi-nozzle fusion control system and relates to the technical field of 3D printing. The value range of an offset cause analysis index FXZs is compared with a first comparison threshold A, the causes of nozzle offset, nozzle driving system and nozzle state are analyzed, and an adhesive quality monitoring index NHJc is analyzed with a second comparison threshold B, so that it is judged whether a second calibration module needs to fine-tune the calibration value of a first calibration module, the height difference effect is reduced, and the quality of a formed workpiece is improved.

Description

Technical Field

[0001] This invention belongs to the field of 3D printing technology, specifically relating to a multi-nozzle fusion control system for 3D printing of powder materials. Background Technology

[0002] Powder inkjet 3D printers typically use powder materials, such as plaster powder or metal powder. Ink is usually a binder that cures on each layer, binding the powder together. The specific steps include uniformly distributing the powder, spraying ink, adding another layer of powder, and repeating this process until the object is built layer by layer. After printing, post-processing steps are usually required to improve its structural strength or aesthetics. In the above process, depending on the complexity of the workpiece, multiple nozzles are needed to spray the binder onto the powder layer surface spread on the build platform in a high-precision and uniform manner. The accuracy of the workpiece depends on the calibration control system in the multi-nozzle fusion control system and the spraying quality of the binder.

[0003] Chinese patent CN111267340B discloses a nozzle calibration method and system for a dual-nozzle 3D printer. The nozzle calibration method includes establishing a Cartesian coordinate system on the heated bed of the 3D printer; calculating the offset value between the left and right nozzles along the X-axis to obtain a first offset value; calculating the offset value between the left and right nozzles along the Y-axis to obtain a second offset value; calibrating the left and right nozzles based on the first and second offset values; printing different line groups using the left and right nozzles respectively; selecting completely overlapping lines from the two line groups to determine the offset value; and thus avoiding errors caused by manual measurement to determine the offset value, improving the calibration level.

[0004] However, the above solutions have the following shortcomings: existing multi-nozzle calibration control systems for 3D printers are limited to monitoring the position of the nozzles, but cannot intuitively understand the cause of nozzle offset. Furthermore, the goal of nozzle offset calibration is to ensure a high-precision and uniform distribution of the adhesive sprayed onto the powder layer. Since the position and angle at which each nozzle releases the adhesive may differ, height differences may occur when multiple nozzles release adhesive at different angles. This can lead to uneven surface quality, inaccurate dimensions, and reduced structural strength in the molded workpiece. Therefore, further improvements to the multi-nozzle calibration control system for 3D printers are needed to enable it to analyze the causes of nozzle offset based on multi-nozzle positioning calibration, and to detect the quality of the adhesive sprayed onto the powder layer for secondary calibration control of the multiple nozzles, reducing the height difference effect and improving the quality of the molded workpiece. Summary of the Invention

[0005] The purpose of this invention is to provide a multi-nozzle fusion control system for 3D printing of powder materials to solve the problems existing in the background art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a multi-nozzle fusion control system for powder material 3D printing, comprising:

[0007] Acquisition module: used to acquire multi-nozzle offset data PTPy and nozzle status data PTZt for each nozzle, acquire nozzle drive system status data PTQd and adhesive layer distribution image data NHJFb on the powder layer and transmit them to the processing module;

[0008] Processing module: used to receive the multi-nozzle offset data PTPy, nozzle status data PTZt and nozzle drive system status data PTQd, analyze them to generate offset cause analysis index FXZs, and use it to analyze and determine the cause of nozzle offset by comparing it with the first comparison threshold A.

[0009] Receive the adhesive layer distribution image data NHJFb and analyze it to generate the adhesive quality monitoring index NHJc;

[0010] Calibration Judgment Module: Used to determine whether the adhesive quality monitoring index NHJc is within the corresponding second comparison threshold B, and to select the calibration control mode of the first calibration module or the second calibration module for multiple nozzles.

[0011] Preferably, the multi-nozzle offset data PTPy includes the X-axis offset parameter XPy, the Y-axis offset parameter YPy, and the Z-axis offset parameter ZPy for each nozzle. The dynamic standard time-displacement curves corresponding to the X-axis, Y-axis, and Z-axis for each nozzle in the multi-nozzle set N = [1, 2, ..., n] are set to XPy, [1, 2, ..., n]. DTb YPy DTb and ZPy DTb The discharge time-displacement value of each nozzle in the multi-nozzle set N = [1, 2, ..., n] is compared with the corresponding XPy value. DTb YPy DTb and ZPy DTb The nozzle X-axis offset parameter XPy, nozzle Y-axis offset parameter YPy, and nozzle Z-axis offset parameter ZPy are obtained by performing interpolation calculations. The specific formulas are as follows:

[0012]

[0013]

[0014]

[0015] PTPy=XPy×a1+YPy×a2+ZPy×a3

[0016] in and These are the real-time position values ​​of each nozzle in the multi-nozzle set N = [1, 2, ..., n] on the corresponding X-axis, Y-axis, and Z-axis, respectively, and a1, a2, and a3 are weight values, where 0 < a1 < a2 < a3;

[0017] The range of values ​​for the multi-nozzle offset data PTPy is limited to the open interval (1, 10), which means that the upper limit of the normal offset values ​​of the nozzle X-axis offset parameter XPy, the nozzle Y-axis offset parameter YPy, and the nozzle Z-axis offset parameter ZPy is within the open interval (1, 10) of the multi-nozzle offset data PTPy.

[0018] Preferably, the nozzle drive system status data PTQd includes the drive mechanism error parameter QDPy and the mechanical vibration parameter JXZd;

[0019] The drive mechanism error parameter QDPy is composed of the stepper motor accuracy BJDj and the transmission device accuracy CDZj. The stepper motor accuracy BJDj is set to a value range of 1 to 10, and the transmission device accuracy CDZj is set to a value range of 1 to 10. The larger the value, the higher the corresponding accuracy, and vice versa. The following formula is obtained through analysis and processing:

[0020] QDPy=BJDj×b1+CDZj×b2

[0021] Where b1 and b2 are both weight values, and 0 < b1 < b2;

[0022] The mechanical vibration parameter JXZd is obtained by a vibration sensor to acquire the vibration frequency, amplitude, harmonic analysis and peak acceleration on the nozzle mounting side. The upper limit of the threshold of the mechanical vibration parameter JXZd is set to 1 to 10. The larger the value, the more obvious the vibration force. If the value is 1, it means that the vibration effect is negligible. If the value is 10, it means that the vibration seriously affects the installation accuracy of the nozzle. This is used for the calibration of the first calibration module.

[0023] Preferably, the nozzle status data PTZt includes nozzle wear parameter PTMs, nozzle cleanliness parameter PTQjj, nozzle flow rate parameter PTLl, and nozzle pressure parameter PTYl;

[0024] The nozzle wear parameter PTMs represents the nozzle diameter wear and service life value. Specifically, the wear is evaluated by measuring the roughness of the internal surface of the nozzle. The wear value is set to range from 1 to 10, with the larger the value, the greater the wear.

[0025] The nozzle flow parameters PTLl include nozzle flow rate LLv and flow uniformity JYx.

[0026] Printhead flow rate LLv: represents the volume of material ejected per minute or second, and is related to printing speed and material type;

[0027] Flow uniformity JYx: Indicates whether the material flow is uniform during the printing process, which can be represented by a flow distribution diagram or uniformity index; and the following formula is obtained through analysis:

[0028] PTLl=LLv×c1+JYx×c2

[0029] Where c1 and c2 are weight values, 0 < c1 < c2. When the flow uniformity JYx is abnormal, the output value is 0, indicating that the material flow is not uniform. When the flow uniformity JYx is normal, the output value is positive.

[0030] The printhead pressure parameter PTYl consists of printhead pressure data readings and pressure change rate. The pressure change rate represents the rate of change of internal pressure in the printhead during printing, and is used to determine whether there is an abnormal release of adhesive. The output value of printhead pressure parameter PTYl is mapped to a value range of 1 to 10 after normalization analysis. The closer the value range is to 5, the more stable the pressure change is. When the value range is greater than 5, it indicates that the pressure value changes more, and the printhead needs to be adjusted. When the value range is less than 5, it indicates a state of pressure loss, and the printhead output pressure needs to be increased.

[0031] The following formula is obtained by formulating the nozzle status data PTZt:

[0032] PTZt=PTMs×d1+PTQj×d2+PTLl×d3+PTYl×d4

[0033] Where d1, d2, d3 and d4 are weight values, 0 < d1 < d2 < d3 < d4, 1 < PTZt < 10.

[0034] Preferably, the adhesive layer distribution image data NHJFb includes the adhesive edge accuracy parameter BYJd and the adhesive layer distribution uniformity parameter FBJy; the adhesive edge accuracy parameter BYJd is composed of the adhesive offset value NHJPy and the adhesive deflection angle value NHJPj.

[0035] Adhesive offset: Used to indicate the offset between the actual adhesive line and the expected adhesive line, expressed in millimeters or micrometers, and is used to measure whether the adhesive is deposited precisely in the desired location;

[0036] Adhesive deflection angle: This refers to the angular difference between the actual direction and the ideal direction of the adhesive line. The angle is usually expressed in degrees.

[0037] The formula is then formalized to obtain the following formula:

[0038] BYJd=NHJPy×e1+NHJPj×e2

[0039] Where e1 and e2 are weight values, 0 < e1 < e2, and the comparison threshold for the adhesive edge accuracy parameter BYJd is set to... For range values, when the adhesive edge precision parameter BYJd is within a certain range... When it is within the range, it indicates that the edge of the adhesive meets the accuracy requirements, and it is within the threshold. When the adhesive is outside the specified range, it indicates that the edge precision of the adhesive does not meet the requirements.

[0040] The adhesive layer distribution uniformity parameter FBJy is composed of the coating uniformity index TFJy and the coating material concentration gradient TFTd;

[0041] Coating uniformity index TFJy: The value is used to represent the degree of uniform distribution of the adhesive. The coating uniformity is obtained by acquiring images with a high-speed camera and performing image analysis. It is expressed as a percentage or other standardized units, where 100% represents a completely uniform coating.

[0042] Coating material concentration gradient TFTd: This measures the degree of change in adhesive concentration within the coating area. The smaller the gradient, the more uniform the coating.

[0043] The coating uniformity index TFJy is set to a value from 0 to 1, where 1 represents complete uniformity and 0 represents complete non-uniformity, and the following formula is obtained:

[0044] FBJy=(1-TFJy)×(1-TFTd)

[0045] When both the coating uniformity index TFJy and the coating material concentration gradient TFTd are close to 1, the adhesive layer distribution uniformity parameter will also be close to 1, indicating a very uniform coating. When one or both of these indices decrease, the adhesive layer distribution uniformity parameter will decrease, reflecting coating non-uniformity.

[0046] Preferably, the formula for calculating the offset cause analysis index FXZs is as follows:

[0047]

[0048] Furthermore, the range of the offset cause analysis index FXZs is -1≤FXZs≤1, and the first comparison threshold A is a subset of the range values ​​within the offset cause analysis index FXZs.

[0049] When the actual value of the offset cause analysis index FXZs is -1≤FXZs<A, it means that the value range of PTPy of any one or more nozzles in the nozzle set N=[1、2、3…n] is outside the open interval (1、10). At this time, the real-time position values ​​of any one or more of the X-axis, Y-axis and Z-axis of the corresponding nozzle are in an abnormal offset state.

[0050] When the actual value of the offset cause analysis index FXZs is at the first comparison threshold A, it means that the nozzle drive system status data PTQd of any one or more nozzles in the nozzle set N = [1, 2, 3...n] is outside the range of 1 to 10. At this time, any one or more values ​​of the stepper motor accuracy BJDj, transmission device accuracy CDZj and mechanical vibration parameter JXZd of the corresponding nozzle are in an abnormal state.

[0051] When the actual value of the offset cause analysis index FXZs is A≤FXZs<1, it means that the nozzle status data PTZt of any one or more nozzles in the nozzle set N=[1,2,3…n] is outside the range of 1 to 10. It means that any one or more values ​​of the nozzle wear parameter PTMs, nozzle cleanliness parameter PTQj, nozzle flow parameter PTLl, and nozzle pressure parameter PTYl are in an abnormal state.

[0052] Preferably, the first calibration module: the first calibration module only receives multi-nozzle offset data PTPy, nozzle status data PTZt and nozzle drive system status data PTQd, and performs analysis and processing on the data before calibrating the multi-nozzle;

[0053] Second calibration module: Based on the first calibration module, the second calibration module receives the adhesive layer distribution image data NHJFb, analyzes and processes it, and after fine-tuning the first calibration module, performs precise calibration on multiple nozzles;

[0054] The formula for calculating the adhesive quality monitoring index NHJc is as follows:

[0055]

[0056] The value range of NHJc is set to 0≤FXZs≤1, and the second comparison threshold B is a subset of the range values ​​of NHJc.

[0057] When the value of NHJc falls within the second comparison threshold B, it indicates that the values ​​of the adhesive edge accuracy parameter BYJd and the adhesive layer distribution uniformity parameter FBJy are abnormal. At this time, the second calibration module needs to fine-tune the calibration value of the first calibration module.

[0058] When the value of NHJc falls outside the second comparison threshold B, it indicates that the values ​​of the adhesive edge accuracy parameter BYJd and the adhesive layer distribution uniformity parameter FBJy are in a normal state, and the calibration value of the first calibration module shall be used as the standard.

[0059] Compared with the prior art, the beneficial effects of the present invention are: by comparing the value range of the offset cause analysis index FXZs with the first comparison threshold A, the causes of nozzle offset, nozzle drive system and nozzle status are analyzed. At the same time, the adhesive quality monitoring index NHJc is analyzed with the second comparison threshold B to determine whether the second calibration module needs to fine-tune the calibration value of the first calibration module, thereby reducing the height difference effect and improving the quality of the molded workpiece. Attached Figure Description

[0060] Figure 1 This is a schematic diagram of the process of the present invention;

[0061] Figure 2 This is a schematic diagram of the system flow of the present invention. Detailed Implementation

[0062] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

[0063] Please see Figure 1-2 The present invention provides a technical solution:

[0064] Example 1:

[0065] A multi-nozzle fusion control system for powder material 3D printing includes:

[0066] Acquisition module: used to acquire multi-nozzle offset data PTPy and nozzle status data PTZt, acquire nozzle drive system status data PTQd and adhesive layer distribution image data NHJFb on the powder layer and transmit them to the processing module;

[0067] Processing module: Used to receive multi-nozzle offset data PTPy, nozzle status data PTZt and nozzle drive system status data PTQd, analyze them to generate offset cause analysis index FXZs, and use this index to compare with the first comparison threshold A to analyze and determine the cause of nozzle offset.

[0068] Receive adhesive layer distribution image data NHJFb and analyze it to generate the adhesive quality monitoring index NHJc;

[0069] Calibration Judgment Module: Used to determine whether the adhesive quality monitoring index NHJc is within the corresponding second comparison threshold B, and to select the calibration control mode of the first calibration module or the second calibration module for multiple nozzles.

[0070] Example 2:

[0071] The multi-nozzle offset data PTPy includes the nozzle X-axis offset parameter XPy, the nozzle Y-axis offset parameter YPy, and the nozzle Z-axis offset parameter ZPy. The dynamic standard time-displacement curves for the X-axis, Y-axis, and Z-axis of each nozzle in the multi-nozzle set N = [1, 2, ..., n] are defined as XPy, Y, and Z, respectively. DTb YPy DTb and ZPy DTb The discharge time-displacement value of each nozzle in the multi-nozzle set N = [1, 2, ..., n] is compared with the corresponding XPy value. DTb YPy DTb and ZPy DTb The nozzle X-axis offset parameter XPy, nozzle Y-axis offset parameter YPy, and nozzle Z-axis offset parameter ZPy are obtained by performing interpolation calculations. The specific formulas are as follows:

[0072]

[0073]

[0074]

[0075] PTPy=XPy×a1+YPy×a2+ZPy×a3

[0076] in and These are the real-time position values ​​of each nozzle in the multi-nozzle set N = [1, 2, ..., n] on the corresponding X-axis, Y-axis, and Z-axis, respectively, and a1, a2, and a3 are weight values, where 0 < a1 < a2 < a3;

[0077] The range of values ​​for the multi-nozzle offset data PTPy is limited to the open interval (1, 10), which means that the upper limit of the normal offset values ​​of the nozzle X-axis offset parameter XPy, the nozzle Y-axis offset parameter YPy, and the nozzle Z-axis offset parameter ZPy is within the open interval (1, 10) of the multi-nozzle offset data PTPy.

[0078] Example 3:

[0079] The nozzle drive system status data PTQd includes the drive mechanism error parameter QDPy and the mechanical vibration parameter JXZd;

[0080] The drive mechanism error parameter QDPy is composed of the stepper motor accuracy BJDj and the transmission device accuracy CDZj. The stepper motor accuracy BJDj is set to a value range of 1 to 10, and the transmission device accuracy CDZj is set to a value range of 1 to 10. The larger the value, the higher the corresponding accuracy, and vice versa. The following formula is obtained through analysis and processing:

[0081] QDPy=BJDj×b1+CDZj×b2

[0082] Where b1 and b2 are both weight values, and 0 < b1 < b2;

[0083] The precision (BJDj) and resolution of the stepper motor are crucial to the accuracy of calibration. If the stepper motor is not high-precision or is not properly calibrated, it will lead to deviations in the nozzle position.

[0084] The precision of transmission devices, such as guide rails, screws, and belts, affects the accuracy of nozzle positioning. Wear or loosening of these devices may lead to positioning errors.

[0085] The mechanical vibration parameter JXZd obtains the vibration frequency, amplitude, harmonic analysis and peak acceleration of the nozzle mounting base side through vibration sensors, and sets the upper limit of the threshold of the mechanical vibration parameter JXZd to 1 to 10. The larger the value, the more obvious the vibration force. If the value is 1, it means that the vibration effect is negligible. If the value is 10, it means that the vibration seriously affects the installation accuracy of the nozzle. This is used for the calibration of the first calibration module.

[0086] Frequency: Sensors can detect the frequency of mechanical vibrations, thereby determining whether a specific resonant frequency exists.

[0087] Amplitude: The sensor can measure the amplitude of the vibration, which helps to assess the intensity of the vibration.

[0088] Harmonic analysis: Advanced vibration analysis tools can perform harmonic analysis on data acquired from sensors to determine the different frequency components of vibration.

[0089] Peak acceleration: Some vibration sensors, such as accelerometers, can directly measure peak acceleration, which represents the maximum acceleration value of the vibration.

[0090] Example 4:

[0091] The nozzle condition data PTZt includes the nozzle wear parameter PTMs, the nozzle cleanliness parameter PTQj, the nozzle flow rate parameter PTLl, and the nozzle pressure parameter PTYl;

[0092] The nozzle wear parameter PTMs represents the nozzle diameter wear and service life value. Specifically, wear is assessed by measuring the roughness of the internal surface of the nozzle. The wear value is set to a range of 1 to 10, with higher values ​​indicating greater wear. When the wear value is 1, it indicates no wear, and when the wear value is 10, it indicates that the nozzle is heavily worn and needs to be replaced.

[0093] Nozzle diameter change: Measure the change in the inner or outer diameter of the nozzle over time. A large change indicates that the nozzle has worn out.

[0094] Lifespan: This is expressed as the printing time of the printhead or the amount of printing material consumed. The printhead needs to be replaced after a certain lifespan.

[0095] Surface roughness: Wear is assessed by measuring the roughness of the internal surface of the nozzle.

[0096] The nozzle cleanliness parameter PTQj uses optical sensors or image analysis to detect the degree of clogging of the nozzle surface by impurities or foreign objects. The clogging degree ranges from 1 to 10. The higher the value, the more severe the clogging. When the clogging degree is 1, it means that the nozzle is not clogged. When the clogging degree is 10, it means that the nozzle outlet is completely clogged, which affects the release of the adhesive.

[0097] The nozzle flow parameters PTLl include the nozzle flow rate LLv and the flow uniformity JYx.

[0098] Printhead flow rate LLv: represents the volume of material ejected per minute or per second, and is related to printing speed and material type.

[0099] Flow uniformity JYx: Indicates whether the material flow is uniform during the printing process, which can be represented by a flow distribution diagram or uniformity index; and the following formula is obtained through analysis:

[0100] PTLl=LLv×c1+JYx×c2

[0101] Where c1 and c2 are weight values, 0 < c1 < c2. When the flow uniformity JYx is abnormal, the output value is 0, indicating that the material flow is not uniform. When the flow uniformity JYx is normal, the output value is positive.

[0102] The printhead pressure parameter PTYl consists of printhead pressure data readings and pressure change rate. The pressure change rate represents the rate of change of internal pressure in the printhead during printing, used to determine if there is any abnormal release of adhesive. The output value of printhead pressure parameter PTYl is mapped to a value range of 1 to 10 after normalization analysis. The closer the value is to 5, the more stable the pressure change is. When the value is greater than 5, it indicates that the pressure value changes more, and the printhead needs to be adjusted. When the value is less than 5, it indicates a state of pressure loss, and the printhead output pressure needs to be increased.

[0103] The following formula is obtained by formulating the nozzle status data PTZt:

[0104] PTZt=PTMs×d1+PTQj×d2+PTLl×d3+PTYl×d4

[0105] Where d1, d2, d3 and d4 are all weight values, 0 < d1 < d2 < d3 < d4, 1 < PTZt < 10;

[0106] Example 5:

[0107] The adhesive layer distribution image data NHJFb includes the adhesive edge accuracy parameter BYJd and the adhesive layer distribution uniformity parameter FBJy;

[0108] The adhesive edge accuracy parameter BYJd consists of the adhesive offset value NHJPy and the adhesive deflection angle value NHJPj.

[0109] Adhesive offset: Used to indicate the offset between the actual adhesive line and the expected adhesive line, expressed in millimeters or micrometers, and is used to measure whether the adhesive is deposited precisely in the desired location;

[0110] Adhesive deflection angle: This refers to the angular difference between the actual direction and the ideal direction of the adhesive line. The angle is usually expressed in degrees.

[0111] The formula is then formalized to obtain the following formula:

[0112] BYJd=NHJPy×e1+NHJPj×e2

[0113] Where e1 and e2 are weight values, 0 < e1 < e2, and the comparison threshold for the adhesive edge accuracy parameter BYJd is set to... For range values, when the adhesive edge precision parameter BYJd is within a certain range... When it is within the range, it indicates that the edge of the adhesive meets the accuracy requirements, and it is within the threshold. When the adhesive is outside the specified range, it indicates that the edge precision of the adhesive does not meet the requirements.

[0114] The adhesive layer distribution uniformity parameter FBJy is composed of the coating uniformity index TFJy and the coating material concentration gradient TFTd;

[0115] Coating uniformity index TFJy: The numerical value is used to represent the degree of uniform distribution of the adhesive. The coating uniformity is obtained by acquiring images with a high-speed camera and performing image analysis. It is expressed as a percentage or other standardized units, where 100% represents a completely uniform coating.

[0116] Coating material concentration gradient TFTd: This measures the degree of change in adhesive concentration within the coating area. The smaller the gradient, the more uniform the coating.

[0117] The coating uniformity index TFJy is set to a value from 0 to 1, where 1 represents complete uniformity and 0 represents complete non-uniformity, and the following formula is obtained:

[0118] FBJy=(1-TFJy)×(1-TFTd)

[0119] When both the coating uniformity index TFJy and the coating material concentration gradient TFTd are close to 1, the adhesive layer distribution uniformity parameter will also be close to 1, indicating a very uniform coating. When one or both of these indices decrease, the adhesive layer distribution uniformity parameter will decrease, reflecting coating non-uniformity.

[0120] Example 6:

[0121] The formula for calculating the offset cause analysis index FXZs is as follows:

[0122]

[0123] Furthermore, the range of the offset cause analysis index FXZs is -1≤FXZs≤1, and the first comparison threshold A is a subset of the range values ​​within the offset cause analysis index FXZs.

[0124] When the actual value of the offset cause analysis index FXZs is -1≤FXZs<A, it means that the value range of PTPy of any one or more nozzles in the nozzle set N=[1、2、3…n] is outside the open interval (1、10). At this time, the real-time position values ​​of any one or more of the X-axis, Y-axis and Z-axis of the corresponding nozzle are in an abnormal offset state.

[0125] When the actual value of the offset cause analysis index FXZs is at the first comparison threshold A, it means that the nozzle drive system status data PTQd of any one or more nozzles in the nozzle set N = [1, 2, 3...n] is outside the range of 1 to 10. At this time, any one or more values ​​of the stepper motor accuracy BJDj, transmission device accuracy CDZj and mechanical vibration parameter JXZd of the corresponding nozzle are in an abnormal state.

[0126] When the actual value of the offset cause analysis index FXZs is A≤FXZs<1, it means that the nozzle status data PTZt of any one or more nozzles in the nozzle set N=[1,2,3…n] is outside the range of 1 to 10. It means that any one or more values ​​of the nozzle wear parameter PTMs, nozzle cleanliness parameter PTQj, nozzle flow parameter PTLl, and nozzle pressure parameter PTYl are in an abnormal state.

[0127] Example 7:

[0128] First calibration module: The first calibration module only receives multi-nozzle offset data PTPy, nozzle status data PTZt and nozzle drive system status data PTQd, and performs analysis and processing to calibrate the multi-nozzle;

[0129] Second calibration module: Based on the first calibration module, the second calibration module receives the adhesive layer distribution image data NHJFb, analyzes and processes it, and after fine-tuning the first calibration module, performs precise calibration on multiple nozzles;

[0130] First calibration module steps:

[0131] Nozzle Position Calibration: This section involves ensuring the accurate position and orientation of each adhesive nozzle. This typically includes mechanical calibration to ensure that each nozzle is in the correct position and that their relative positions are consistent. This involves precise mechanical adjustments or the use of sensors to monitor and adjust the nozzle position.

[0132] Nozzle flow calibration: Multi-nozzle systems require ensuring that the adhesive flow rate released by each nozzle is consistent to avoid uneven coating. This may require calibrating the flow rate of each nozzle or adjusting the flow control parameters to ensure that they spray the adhesive evenly.

[0133] Printhead timing synchronization: To ensure that different printheads work in a coordinated manner, printhead calibration modules typically involve printhead timing synchronization. This ensures that multiple printheads release the binder at the appropriate time to create a uniform coating.

[0134] Binder type and concentration adjustment: Different printing jobs may require different types or concentrations of binder. The printhead calibration module may include a parameter setting interface that allows the operator to select the appropriate binder type and concentration to meet specific printing requirements.

[0135] Real-time monitoring and feedback control: Calibration modules typically include real-time monitoring capabilities to detect inconsistencies or problems and provide feedback control when necessary, such as automatically adjusting nozzle position or flow rate to correct any deviations.

[0136] Second calibration module steps:

[0137] Select reference nozzle:

[0138] First, select a binder nozzle as a reference. This is usually a nozzle that is known to be well-calibrated, or one that can be preliminarily calibrated beforehand.

[0139] Creating calibration samples:

[0140] Use all the multi-nozzle adhesive release nozzles to release adhesive simultaneously over a relatively small area. This will create a sample containing adhesive release from multiple nozzles.

[0141] Print edge markers:

[0142] The adhesive is released at the edge of the adhesive sample to create a mark or edge line for subsequent detection.

[0143] Print areas with uniform adhesive coverage:

[0144] Release the adhesive in the central area of ​​the adhesive sample to create a uniform area. This will be used to test the uniformity of the adhesive.

[0145] Print the test pattern:

[0146] Using a reference printhead and other printheads, print a test pattern or design that includes specific structures, such as lines or grids, that can be used to evaluate the distribution and uniformity of the adhesive.

[0147] Scan or capture images:

[0148] Using visual or sensing technologies, scan or photograph the entire printed sample, including the edges of the markings, uniform areas, and detection patterns.

[0149] Image processing and analysis:

[0150] Processing and analyzing the acquired images to evaluate the edges and uniformity of the adhesive requires the use of existing edge detection algorithms to detect edge lines and density analysis to evaluate uniformity.

[0151] Adjust calibration parameters:

[0152] Based on the image analysis results, the calibration parameters of the multi-nozzle system were adjusted. This included adjusting parameters such as binder flow rate, nozzle position, and time synchronization to improve binder distribution and uniformity.

[0153] Recalibrate:

[0154] Repeat the above steps until the required adhesive distribution and uniformity standards are met.

[0155] The formula for calculating the adhesive quality monitoring index NHJc is:

[0156]

[0157] The range of NHJc is set to 0≤FXZs≤1, and the second comparison threshold B is a subset of the range of NHJc values.

[0158] When the value of NHJc falls within the second comparison threshold B, it indicates that the values ​​of the adhesive edge accuracy parameter BYJd and the adhesive layer distribution uniformity parameter FBJy are abnormal. At this time, the second calibration module needs to fine-tune the calibration value of the first calibration module.

[0159] When the value of NHJc falls outside the second comparison threshold B, it indicates that the values ​​of the adhesive edge accuracy parameter BYJd and the adhesive layer distribution uniformity parameter FBJy are in a normal state, and the calibration value of the first calibration module shall be used as the standard.

[0160] The above embodiments can be implemented, in whole or in part, by software, hardware, firmware, or any other combination thereof. When implemented using software, the above embodiments can be implemented, in whole or in part, as a computer program product. The computer program product includes one or more computer instructions or computer programs. When the computer instructions or computer programs are loaded or executed on a computer, all or part of the processes or functions described in the embodiments of this application are generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, the computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via wired (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium can be any available medium that a computer can access or a data storage device such as a server or data center that includes one or more sets of available media. The available medium can be a magnetic medium (e.g., floppy disk, hard disk, magnetic tape), an optical medium (e.g., DVD), or a semiconductor medium. A semiconductor medium can be a solid-state drive.

[0161] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0162] Those skilled in the art will understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0163] In the several embodiments provided in this application, it should be understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative. For instance, the division of units is only a logical functional division of a waterway underwater topography change analysis system and method. In actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces, indirect coupling or communication connection between devices or units, and may be electrical, mechanical, or other forms.

[0164] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0165] In addition, 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.

[0166] If the aforementioned functions are implemented as software functional units and sold or used as independent products, they can be stored in a computer-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 a portion 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.) 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.

[0167] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A multi-nozzle fusion control system for 3D printing of powder materials, characterized in that, include: Acquisition module: used to acquire multi-nozzle offset data PTPy and nozzle status data PTZt, acquire nozzle drive system status data PTQd and adhesive layer distribution image data NHJFb on the powder layer and transmit them to the processing module; Processing module: used to receive the multi-nozzle offset data PTPy, nozzle status data PTZt and nozzle drive system status data PTQd, analyze them to generate offset cause analysis index FXZs, and use it to analyze and determine the cause of nozzle offset by comparing it with the first comparison threshold A. Receive the adhesive layer distribution image data NHJFb and analyze it to generate the adhesive quality monitoring index NHJc; Calibration judgment module: used to determine whether the adhesive quality monitoring index NHJc is within the corresponding second comparison threshold B, and to select the calibration control mode of the first calibration module or the second calibration module for multiple nozzles; The multi-nozzle offset data PTPy includes the X-axis offset parameter XPy, the Y-axis offset parameter YPy, and the Z-axis offset parameter ZPy for each nozzle, setting multiple nozzles on the 3D printer to form a multi-nozzle set. And multiple nozzles are combined The dynamic standard time-displacement curves for each nozzle along the X, Y, and Z axes are as follows: , and Combining multiple nozzles The discharge time-displacement value of each nozzle and its corresponding value , and The nozzle X-axis offset parameter XPy, nozzle Y-axis offset parameter YPy, and nozzle Z-axis offset parameter ZPy are obtained by performing interpolation calculations. The specific formulas are as follows: in , and They are multi-nozzle sets The real-time position values ​​of each nozzle on the corresponding X-axis, Y-axis and Z-axis, with a1, a2 and a3 being weight values, where 0 < a1 < a2 < a3; The range of values ​​for the multi-nozzle offset data PTPy is limited to the open interval (1, 10), which means that the upper limit of the normal offset values ​​of the nozzle X-axis offset parameter XPy, the nozzle Y-axis offset parameter YPy, and the nozzle Z-axis offset parameter ZPy is within the open interval (1, 10) of the multi-nozzle offset data PTPy.

2. The powder material 3D printing multi-jet fusion control system of claim 1, wherein: The nozzle drive system status data PTQd includes the drive mechanism error parameter QDPy and the mechanical vibration parameter JXZd. The drive mechanism error parameter QDPy is composed of the stepper motor accuracy BJDj and the transmission device accuracy CDZj. The stepper motor accuracy BJDj is set to a value range of 1 to 10, and the transmission device accuracy CDZj is set to a value range of 1 to 10. The larger the value, the higher the corresponding accuracy, and vice versa. The following formula is obtained through analysis and processing: Where b1 and b2 are both weight values, and 0 < b1 < b2; The mechanical vibration parameter JXZd is obtained by a vibration sensor to acquire the vibration frequency, amplitude, harmonic analysis and peak acceleration on the nozzle mounting side. The upper limit of the threshold of the mechanical vibration parameter JXZd is set to 1 to 10. The larger the value, the more obvious the vibration force. If the value is 1, it means that the vibration effect is negligible. If the value is 10, it means that the vibration seriously affects the installation accuracy of the nozzle. This is used for the calibration of the first calibration module.

3. The multi-nozzle fusion control system for powder material 3D printing according to claim 1, characterized in that: The nozzle status data PTZt includes nozzle wear parameter PTMs, nozzle cleanliness parameter PTQj, nozzle flow rate parameter PTLl, and nozzle pressure parameter PTYl; The nozzle wear parameter PTMs represents the nozzle diameter wear and service life value. Specifically, the wear is evaluated by measuring the roughness of the internal surface of the nozzle. The wear value is set to range from 1 to 10, with the larger the value, the greater the wear. The nozzle flow parameters PTLl include nozzle flow rate LLv and flow uniformity JYx. Printhead flow rate LLv: represents the volume of material ejected per minute or second, and is related to printing speed and material type; Flow uniformity JYx: Indicates whether the material flow is uniform during the printing process, which can be represented by a flow distribution diagram or uniformity index; The following formula was obtained through analysis: Where c1 and c2 are weight values, 0 < c1 < c2. When the flow uniformity JYx is abnormal, the output value is 0, indicating that the material flow is not uniform. When the flow uniformity JYx is normal, the output value is positive. The printhead pressure parameter PTYl consists of printhead pressure data readings and pressure change rate. The pressure change rate represents the rate of change of internal pressure in the printhead during printing, and is used to determine whether there is an abnormal release of adhesive. The output value of printhead pressure parameter PTYl is mapped to a value range of 1 to 10 after normalization analysis. The closer the value range is to 5, the more stable the pressure change is. When the value range is greater than 5, it indicates that the pressure value changes more, and the printhead needs to be adjusted. When the value range is less than 5, it indicates a state of pressure loss, and the printhead output pressure needs to be increased. The following formula is obtained by formulating the nozzle status data PTZt: Where d1, d2, d3 and d4 are weight values, 0 < d1 < d2 < d3 < d4, 1 < PTZt < 10.

4. The multi-nozzle fusion control system for powder material 3D printing according to claim 1, characterized in that: The adhesive layer distribution image data NHJFb includes the adhesive edge accuracy parameter BYJd and the adhesive layer distribution uniformity parameter FBJy; the adhesive edge accuracy parameter BYJd is composed of the adhesive offset value NHJPy and the adhesive deflection angle value NHJPj. Adhesive offset: Used to indicate the offset between the actual adhesive line and the expected adhesive line, expressed in millimeters or micrometers, and is used to measure whether the adhesive is deposited precisely in the desired location; Adhesive deflection angle: This refers to the angular difference between the actual direction and the ideal direction of the adhesive line. The angle is usually expressed in degrees. The formula is then formalized to obtain the following formula: Where e1 and e2 are weight values, 0 < e1 < e2, and the comparison threshold for the adhesive edge accuracy parameter BYJd is set to... , For range values, when the adhesive edge precision parameter BYJd is within a certain range... When it is within the range, it indicates that the edge of the adhesive meets the accuracy requirements, and it is within the threshold. When the adhesive is outside the specified range, it indicates that the edge precision of the adhesive does not meet the requirements. The adhesive layer distribution uniformity parameter FBJy is composed of the coating uniformity index TFJy and the coating material concentration gradient TFTd; Coating uniformity index TFJy: The value is used to represent the degree of uniform distribution of the adhesive. The coating uniformity is obtained by acquiring images with a high-speed camera and performing image analysis. It is expressed as a percentage or other standardized units, where 100% represents a completely uniform coating. Coating material concentration gradient TFTd: This measures the degree of change in adhesive concentration within the coating area. The smaller the gradient, the more uniform the coating. The coating uniformity index TFJy is set to a value from 0 to 1, where 1 represents complete uniformity and 0 represents complete non-uniformity, and the following formula is obtained: When both the coating uniformity index TFJy and the coating material concentration gradient TFTd are close to 1, the adhesive layer distribution uniformity parameter will also be close to 1, indicating a very uniform coating. When one or both of these indices decrease, the adhesive layer distribution uniformity parameter will decrease, reflecting coating non-uniformity.

5. The multi-nozzle fusion control system for powder material 3D printing according to claim 1, characterized in that: The formula for calculating the offset cause analysis index FXZs is as follows: Furthermore, the range of the offset cause analysis index FXZs is -1≤FXZs≤1, and the first comparison threshold A is a subset of the range values ​​within the offset cause analysis index FXZs. When the actual value of the offset cause analysis index FXZs is -1 ≤ FXZs < A, it indicates that the nozzle set If the PTPy value of any one or more nozzles is outside the open interval (1, 10), then the real-time position value of any one or more of the X-axis, Y-axis and Z-axis of the corresponding nozzle is in an abnormal offset state. When the actual value of the offset cause analysis index FXZs is at the first comparison threshold A, it indicates that the nozzle set If the nozzle drive system status data PTQd of any one or more nozzles is outside the range of 1 to 10, then any one or more of the following values ​​of the corresponding nozzle stepper motor accuracy BJDj, transmission device accuracy CDZj, and mechanical vibration parameter JXZd are in an abnormal state. When the actual value of the offset cause analysis index FXZs is A≤FXZs<1, it indicates that the nozzle set If the nozzle status data PTZt of any one or more nozzles is outside the range of 1 to 10, it indicates that any one or more of the following parameters are in an abnormal state: nozzle wear parameter PTMs, nozzle cleanliness parameter PTQj, nozzle flow parameter PTLl, and nozzle pressure parameter PTYl.

6. The multi-nozzle fusion control system for powder material 3D printing according to claim 1, characterized in that: The first calibration module: The first calibration module only receives multi-nozzle offset data PTPy, nozzle status data PTZt and nozzle drive system status data PTQd, and performs analysis and processing to calibrate the multi-nozzle; Second calibration module: Based on the first calibration module, the second calibration module receives the adhesive layer distribution image data NHJFb, analyzes and processes it, and after fine-tuning the first calibration module, performs precise calibration on multiple nozzles; The formula for calculating the adhesive quality monitoring index NHJc is as follows: The value range of NHJc is set to 0≤FXZs≤1, and the second comparison threshold B is a subset of the range values ​​of NHJc. When the value of NHJc falls within the second comparison threshold B, it indicates that the values ​​of the adhesive edge accuracy parameter BYJd and the adhesive layer distribution uniformity parameter FBJy are abnormal. At this time, the second calibration module needs to fine-tune the calibration value of the first calibration module. When the value of NHJc falls outside the second comparison threshold B, it indicates that the values ​​of the adhesive edge accuracy parameter BYJd and the adhesive layer distribution uniformity parameter FBJy are in a normal state, and the calibration value of the first calibration module shall be used as the standard.

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