Printing anomaly detection method of 3D printing equipment, 3D printing equipment and storage medium

Abstract

The invention provides a printing anomaly detection method of 3D printing equipment, the 3D printing equipment and a storage medium, and relates to the field of 3D printing. The 3D printing equipment comprises a printing platform and a material groove, and the method comprises the steps that the printing platform is controlled to be lifted in the vertical direction so as to drive a model layer on the printing platform to be separated from a release film at the bottom of the material groove; in the lifting process of the printing platform, a detection value used for representing the stress condition of the printing platform is obtained; and according to the detection value, whether the 3D printing equipment has the abnormal condition of model printing failure or not is judged. According to the method, a user can conveniently and timely find the abnormity and take countermeasures according to the abnormity, the problem of printing failure or poor model quality caused by the abnormity is avoided, the production process is more efficient through real-time abnormity detection, the model manufacturing period is shortened, the rejection rate is reduced, manual intervention is not needed, and the production efficiency is improved. And the risk of human error judgment is reduced.

Description

Technical Field

[0001] The present application relates to the field of 3D printing, and in particular to a printing anomaly detection method for a 3D printing device, a 3D printing device, and a readable storage medium. Background Art

[0002] During stereolithography 3D printing, due to the limitations of the accuracy and stability of stereolithography, abnormal conditions such as bottom dropout may occur during the printing process, resulting in model printing failure or degradation of model quality.

[0003] In the related art, staff can only discover the abnormality when printing fails, or discover the abnormality through later inspection of the model, which leads to a longer model manufacturing cycle and an increase in the scrap rate. Summary of the Invention

[0004] In view of this, the present application provides a printing abnormality detection method for a 3D printing device, a 3D printing device and a readable storage medium, which realizes real-time and automatic judgment of whether the 3D printing device has an abnormal situation of model printing failure based on the detection value of the force condition of the printing platform.

[0005] In a first aspect, an embodiment of the present application provides a method for detecting printing anomalies in a 3D printing device, wherein the 3D printing device includes a printing platform and a material trough, and the method includes:

[0006] Controlling the printing platform to lift in a vertical direction to drive the model layer on the printing platform to separate from the release film at the bottom of the trough;

[0007] During the process of raising the printing platform, obtaining a detection value for characterizing a force condition of the printing platform;

[0008] According to the detection value, it is determined whether an abnormal situation of model printing failure occurs in the 3D printing device.

[0009] In a second aspect, an embodiment of the present application provides a 3D printing device, comprising:

[0010] A material trough, for containing the material to be cured;

[0011] A printing platform, used to carry the printed model, and the printing platform moves relative to the material trough to realize model printing;

[0012] a memory storing programs or instructions;

[0013] A processor, wherein when the processor executes the program or instruction, the steps of the method according to the first aspect are implemented.

[0014] In a third aspect, an embodiment of the present application provides a readable storage medium, which stores a program or instruction. When the program or instruction is executed by a processor, the steps of the method of the first aspect are implemented.

[0015] In an embodiment of the present application, after the light source exposes the model layer, the printing platform is controlled to lift in the vertical direction. During the lifting process of the printing platform, the model layer on the printing platform is separated from the release film at the bottom of the material trough to achieve release. During the lifting process, the detection value used to characterize the stress condition of the printing platform is obtained in real time. Then, based on the detection value, it is judged whether the 3D printing device has an abnormal situation of model printing failure. In an embodiment of the present application, the stress condition of the printing platform is detected in real time during the printing process. According to the detection value of the stress condition of the printing platform, it is judged in real time and automatically whether the 3D printing device has an abnormal situation of printing failure such as model bottom falling off, model incompleteness, model fault, etc., which is convenient for users to discover abnormalities in time and take countermeasures according to the abnormalities, so as to avoid the problem of printing failure or poor model quality caused by abnormal conditions. The real-time detection of abnormalities makes the production process more efficient, reduces the model manufacturing cycle, reduces the scrap rate, and does not require manual intervention, reducing the risk of human judgment errors.

[0016] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0018] Figure 1 A schematic diagram showing a flow chart of a method for detecting printing anomalies in a 3D printing device according to an embodiment of the present application is shown;

[0019] Figure 2 A schematic diagram showing a curve of changes in detection values ​​of the release film by the printing model during the process of the printing platform entering and exiting the liquid surface in an embodiment of the present application is shown. DETAILED DESCRIPTION

[0020] The following will be combined with the accompanying drawings in the embodiments of the present application to clearly describe the technical solutions in the embodiments of the present application. Obviously, the embodiments described are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field are within the scope of protection of this application.

[0021] The terms "first," "second," and the like in the specification and claims of this application are used to distinguish similar objects, and are not used to describe a specific order or precedence. It should be understood that the terms used in this manner are interchangeable where appropriate, so that the embodiments of this application can be implemented in an order other than that illustrated or described herein, and that the objects distinguished by "first," "second," and the like are generally of the same type, and do not limit the number of objects; for example, the first object can be one or more. In addition, the term "and / or" in the specification and claims refers to at least one of the connected objects, and the character " / " generally indicates that the objects connected are in an "or" relationship.

[0022] The following, in conjunction with the accompanying drawings, describes in detail the printing anomaly detection method for a 3D printing device, the 3D printing device, and the readable storage medium provided in the embodiments of the present application through specific embodiments and their application scenarios.

[0023] The embodiment of the present application provides a method for detecting printing anomalies of a 3D printing device, wherein the 3D printing device includes a printing platform and a material trough, such as Figure 1 As shown, the method includes:

[0024] Step 101: Control the printing platform to lift vertically to drive the model layer on the printing platform to separate from the release film at the bottom of the trough;

[0025] Step 102: Acquire a detection value representing a force condition of the printing platform during the process of the printing platform being lifted;

[0026] Step 103: Determine, based on the detection value, whether the 3D printing device has an abnormal situation of model printing failure.

[0027] In this embodiment, after the print platform enters the vat, a light source exposes the model layer on the print platform. After exposure, the print platform is controlled to rise vertically. During this rise, the model layer on the print platform detaches from the release film at the bottom of the vat, achieving release. The lifting process of the model layer is the model layer release process. During this lifting process, a detection value representing the force applied to the print platform is acquired in real time. Based on this detection value, it is then determined whether the 3D printing device has experienced an abnormal failure in model printing. It is understood that the above detection value can be used to determine whether the force applied to the current model layer has abnormally increased or decreased, thereby more accurately identifying printing failures of the 3D printing device. Model printing failures can include model bottom dropout, model incompleteness, model faults, and other printing failures. Model bottom dropout occurs when the entire model loses adhesion to the print platform and detaches from the print platform. Model incompleteness occurs when at least a portion of the currently printed model layer fails to adhere to the printed model body during the rise of the print platform, remaining on the release film or failing to cure successfully. Model fault means that the middle part of the model breaks, causing the lower part of the model to separate from the upper part, resulting in the loss of force between the lower part of the model and the printing platform, that is, part of the model detaches from the printing platform.

[0028] In one embodiment, the stress conditions on the printing platform are detected by installing a detection device on the cantilever of the 3D printing device. Alternatively, a detection device is installed on the trough to detect the tension of the release film, thereby indirectly reflecting the stress conditions on the printing platform. Alternatively, other detection methods can be used to install detection structures at relevant locations to detect the stress conditions on the printing platform, and this is not particularly limited here.

[0029] Among them, the detection device can be a force detection device, a deformation detection device, etc., specifically an elastic resistance strain gauge, a tension sensor, etc., which can detect the deformation amount at a specific position of a specific component and other physical quantities that can express its force changes, such as tension, gravity, pressure, torque, etc. When the detection device is set on the cantilever of the 3D printing equipment, after the printing platform is mounted on the cantilever, the printing platform will exert a pulling effect on the cantilever, causing the cantilever to deform slightly. By measuring the deformation of the cantilever, the weight of the printing platform can be obtained. During the lifting process of the printing platform, the gravity of the model and the tension of the release film (i.e., the release force) exerted on the printing platform will also indirectly reflect the deformation of the cantilever. Therefore, the force condition of the printing platform can be obtained through the detection device.

[0030] In an embodiment of the present application, the stress condition of the printing platform is detected in real time during the printing process. Based on the detection value of the stress condition of the printing platform, it is automatically determined in real time whether the 3D printing device has any abnormal printing failure such as model bottom falling off, model defect, or model incompleteness. This facilitates users to promptly discover abnormalities and take countermeasures based on the abnormalities, thereby avoiding printing failures or poor model quality caused by abnormal conditions. The real-time detection of abnormalities makes the production process more efficient, shortens the model manufacturing cycle, reduces the scrap rate, and eliminates the need for human intervention, reducing the risk of human judgment errors.

[0031] In one embodiment of the present application, the detection value includes a first detection value and a second detection value. Judging whether an abnormal situation of model printing failure occurs in the 3D printing device based on the detection values ​​includes:

[0032] Based on the magnitude relationship between the first detection value and the second detection value, an abnormal situation of model printing failure in the 3D printing device is determined, where the first detection value and the second detection value are detection values ​​obtained at different time points or different time intervals during the process of lifting the printing platform, where the different time intervals overlap or do not overlap with each other.

[0033] In this embodiment, the detection value includes a first detection value and a second detection value, that is, during the lifting process, two different detection values ​​are obtained in real time to characterize the stress condition of the printing platform. It is understandable that the first detection value and the second detection value can be detection values ​​obtained at different time points or different time intervals during the lifting of the printing platform, wherein different time intervals may overlap or not overlap with each other. For example, the first detection value is obtained at the first time point during the lifting of the printing platform, and the second detection value is obtained at the second time point during the lifting of the printing platform; or, the first detection value is obtained within the first time interval during the lifting of the printing platform, and the second detection value is obtained within the second time interval during the lifting of the printing platform. Then, through the relationship between the two different detection values, the change in the stress on the printing platform during the release process is judged, thereby monitoring whether the 3D printing device has a problem of model printing failure.

[0034] Through the above method, timely detection of model printing failures during the printing process is achieved, which improves detection efficiency, saves a lot of time, ensures that the printed model has higher quality, and thus improves the performance and reliability of the final product.

[0035] In one embodiment of the present application, determining that an abnormal situation of a model printing failure occurs in a 3D printing device based on a magnitude relationship between a first detection value and a second detection value includes: determining that an abnormal situation of a model printing failure occurs in the 3D printing device when the first detection value and the second detection value meet a preset condition;

[0036] Among them, the preset conditions include one or more of the following conditions: the difference between the first detection value and the second detection value is less than or equal to the preset threshold, the absolute value of the difference between the first detection value and the second detection value is less than or equal to the preset threshold, the change slope of the first detection value and the second detection value with respect to the time axis is less than the preset change slope, and the ratio of the first detection value to the second detection value is within the preset ratio range.

[0037] In this embodiment, when the first detection value and the second detection value meet the preset judgment conditions for model printing failure, it can be determined that the 3D printing device has an abnormal situation of model printing failure. Among them, the preset judgment condition for model printing failure can be that the difference between the first detection value and the second detection value or the absolute value of the difference is less than or equal to a preset threshold value, or it can be that the change slope of the first detection value and the second detection value with respect to the time axis is less than a preset change slope, that is, the rate of change of the detection value within a preset time period, or it can be that the ratio of the first detection value to the second detection value is within a preset ratio range. Through any of the above conditions, it is possible to determine whether the stress condition of the printed model has undergone a certain change during the lifting process, thereby accurately detecting whether the 3D printing device has an abnormal situation of model printing failure, thereby improving the flexibility of detection.

[0038] In one embodiment of the present application, the detection value includes a detection value obtained during the lifting process of the printing platform when printing a model layer, or a detection value obtained during the lifting process of each printing platform when continuously printing multiple model layers; when the first detection value and the second detection value meet a preset condition, determining that the 3D printing device has an abnormal situation of model printing failure includes:

[0039] When the first detection value and the second detection value of a model layer meet a preset condition, determining that an abnormal situation of model printing failure occurs in the 3D printing device; or

[0040] When the first detection values ​​and the second detection values ​​of a plurality of consecutive model layers all meet the preset conditions, it is determined that an abnormal situation of model printing failure occurs in the 3D printing device.

[0041] In this embodiment, in one case, the obtained detection value can be one, which is the detection value obtained during the process of lifting the printing platform when printing a model layer. The detection value includes a first detection value and a second detection value, that is, the first detection value and the second detection value are obtained during the release process corresponding to printing a model layer.

[0042] In order to improve detection efficiency, when the first detection value and the second detection value corresponding to a model layer meet preset conditions, it can be determined that an abnormal situation of model printing failure has occurred in the 3D printing device.

[0043] In another case, multiple detection values ​​can be obtained. That is, when printing multiple model layers continuously, a detection value is obtained during the release process corresponding to each model layer, thereby obtaining multiple detection values, and each detection value includes a first detection value and a second detection value. For example, when printing three model layers continuously, the first detection value is obtained during the process of raising the printing platform to print the first model layer, the second detection value is obtained during the process of raising the printing platform to print the second model layer, and the third detection value is obtained during the process of raising the printing platform to print the third model layer.

[0044] In order to ensure the accuracy of judgment, the abnormal situation of model bottom falling can be determined only when the first detection value and the second detection value corresponding to each model layer in multiple consecutive model layers meet the preset conditions, avoiding the misjudgment and unreliability caused by using one model layer for judgment, and improving the accuracy of detecting abnormal situations in the printing process.

[0045] In one embodiment of the present application, obtaining the first detection value and the second detection value includes:

[0046] The higher detection value of the printing platform during the process of lifting the printing platform after the model layer is exposed is used as the first detection value, and the lower detection value of the printing platform during the process of lifting the printing platform after the model layer is exposed is used as the second detection value; or

[0047] The detection value of the printing platform during the process of separating the printing platform from the material tank is used as the first detection value, and the detection value of the printing platform after the printing platform and the material tank are separated is used as the second detection value; or

[0048] The highest detection value of the printing platform during the process of lifting the printing platform after the model layer is exposed is used as the first detection value, and according to the area of ​​the currently printed model layer, one of the following methods is selected as the method for determining the second detection value: the lowest detection value of the printing platform during the process of lifting the printing platform after the model layer is exposed is determined as the second detection value, and the detection value of the printing platform after the printing platform and the material tank are separated is used as the second detection value;

[0049] The high value of the detection value of the printing platform in the process of lifting the printing platform after the model layer is exposed is used as the first detection value, and according to whether the printing platform passes through the liquid surface in the process of lifting the printing platform after the model layer is exposed, one of the following methods is selected as the method for determining the second detection value: the low value of the detection value of the printing platform in the process of lifting the printing platform after the model layer is exposed is determined as the second detection value, and the detection value of the printing platform after the printing platform and the material tank are separated is used as the second detection value.

[0050] In this embodiment, the manner of determining the first detection value and the second detection value may include any one of the following:

[0051] (1) During the process of lifting the printing platform after the model layer is exposed, the detection value used to characterize the stress condition of the printing platform is monitored, and the high value is used as the first detection value, and the low value is used as the second detection value.

[0052] It should be noted that during the lifting process of the printing platform, there may be a stage where the printing platform is lifted and the liquid level of the to-be-cured material in the trough is discharged, that is, the liquid level stage. However, through extensive experimental research and analysis, the researchers of this application found that when the printing platform is discharged, the material adsorption force exerted by the to-be-cured material in the trough on the printing platform will cause the release adsorption force of the release film of the trough to the model carried by the printing platform to be superimposed, so that the detection value at this time cannot accurately reflect the magnitude of the release adsorption force exerted on the printing platform. For example, during the liquid surface exit stage, the lifting end detection value (the lifting end detection value in this application refers to the detection value corresponding to the lifting of the printing platform and the separation of the material trough) will be pulled up, creating the illusion that the judgment condition of the first detection value (in this embodiment, the maximum value of the detection value of the release process of the platform lifting) - lifting end detection value < preset threshold is satisfied. However, the lifting end detection value at this time cannot accurately reflect the magnitude of the release adsorption force exerted on the printing platform. After the model carried by the printing platform has been separated from the release film (that is, after the release is completed), it is very likely that the release adsorption force that is basically close to 0 at this time is superimposed on the larger material adsorption force, which makes the detection value larger as a whole. In this case, judging that a printing abnormality has occurred based on the first detection value - lifting end detection value < preset threshold is likely to lead to the problem of misjudgment of printing failure.

[0053] For example, Figure 2 The curve of the change of the detection value used to characterize the force of the printing platform during the process of the printing platform entering and exiting the liquid surface is shown. The process of the printing platform entering and exiting the liquid surface refers to the process state of the printing platform being lifted from below the liquid surface of the to-be-cured material to above the liquid surface of the to-be-cured material. Figure 2 As shown, there are two peaks a and b on the curve. Peak a is the maximum value of the release adsorption force generated by the separation when the model carried by the printing platform is separated from the release film. Peak b is the maximum value of the material adsorption force formed by the to-be-cured material on the printing platform when the printing platform emerges from below the liquid surface. The value of peak b will increase the corresponding detection value after the printing platform is lifted after peak a and the release film of the material tank is separated, which may easily lead to the problem of misjudging as a printing failure.

[0054] In order to solve the above-mentioned problem of misjudgment of printing failure, the present application uses the high and low values ​​detected during the process of lifting the printing platform to judge printing failure, so as to ensure the accuracy of the judgment. Among them, the high value can refer to the maximum value, which is likely to appear during the process of separation of the model on the printing platform and the release film, such as at the moment of separation; the low value can refer to the minimum value, which is likely to appear after the model on the printing platform is separated from the release film, such as after the printing platform is released and the force tends to be flat. Determining whether printing has failed by the size relationship between the high and low values ​​can avoid the influence of the judgment of printing failure due to the large detection value of the printed model out of the liquid surface, thereby ensuring that the judgment of printing failure is more reliable.

[0055] (2) Monitoring the detection value used to characterize the force condition of the printing platform during the process of lifting the printing platform after the model layer is exposed, taking the detection value corresponding to the process of separating the printing platform from the material tank as the first detection value, and taking the detection value corresponding to the separation of the printing platform from the material tank as the second detection value.

[0056] As described above, a high detection value will appear when the model on the printing platform is separated from the release film, and a low detection value will appear after the model on the printing platform is separated from the release film. Therefore, the detection value when the model on the printing platform is separated from the release film can be directly recorded as the first detection value, and the detection value after the model on the printing platform is separated from the release film can be directly recorded as the second detection value, so as to judge the printing failure and avoid the problem of misjudgment.

[0057] (3) During the process of lifting the printing platform after the model layer is exposed, the detection value used to characterize the force condition of the printing platform is monitored, and the high value is used as the first detection value, and the low value is used as the second detection value according to the area of ​​the currently printed model layer, or the detection value of the printing platform after the printing platform and the material tank are separated is used as the second detection value.

[0058] Through experimental research and comparison, the researchers of this application have found that the release force of current printed models is likely correlated with the area of ​​the printed model: the larger the area, the greater the release force, and vice versa. Therefore, this application can determine the second detection value based on the size of the printed model to adapt to the print failure judgment of model layers with different exposure areas, ensuring the accuracy of print failure judgment.

[0059] (4) Monitoring the detection value used to characterize the stress condition of the printing platform during the process of lifting the printing platform after the model layer is exposed, with the higher value being used as the first detection value, and the lower value being used as the second detection value based on whether the printing platform passes through the liquid surface during the process of lifting the printing platform after the model layer is exposed, or the detection value of the printing platform after the printing platform is separated from the material tank being used as the second detection value.

[0060] As described above, during the stage of the print platform's lift, when it's above the liquid surface, the adhesion force of the to-be-cured material on the print platform is superimposed on the release film's adhesion force on the model carried by the print platform. Consequently, the detection value at this point cannot accurately reflect the magnitude of the release force acting on the print platform, affecting the judgment of model printing failures. Therefore, the above embodiment determines the second detection value based on whether the print platform passes through the liquid surface during the process of lifting the print platform after the model layer is exposed, enabling accurate judgment of printing failures.

[0061] The present application defines a plurality of ways of determining the first detection value and the second detection value, which can adapt to a variety of different actual printing situations and improve the flexibility and reliability of judging printing failure situations.

[0062] In one embodiment of the present application, the high value includes one or more values; the low value includes one or more values;

[0063] When the high value includes a value, the high value is the maximum value of the detection value of the printing platform during the process of lifting the printing platform; when the low value includes a value, the low value is the minimum value of the detection value of the printing platform during the process of lifting the printing platform; or,

[0064] When the high value includes multiple values, the average value of the multiple high values ​​is used as the first detection value; when the low value includes multiple values, the average value of the multiple low values ​​is used as the second detection value.

[0065] In this embodiment, the high value can be a single value or multiple values; the low value can be a single value or multiple values. In one embodiment, when the high value is a single value, it can be the maximum value of the detection value of the printing platform during the process of raising the printing platform, that is, the first detection value is this maximum value; when the low value is a single value, it can be the minimum value of the detection value of the printing platform during the process of raising the printing platform, that is, the second detection value is this minimum value.

[0066] In one embodiment, when the high value is multiple values, the high value can be multiple values ​​within the maximum value interval of the detection value of the printing platform during the process of raising the printing platform, and the maximum value interval includes the maximum value and other large values ​​around the maximum value. In this case, the first detection value is the average of these multiple values. When the low value is multiple values, the low value can be multiple values ​​within the minimum value interval of the detection value of the printing platform during the process of raising the printing platform. The minimum value interval includes the minimum value and other small values ​​around the minimum value. In this way, the acquisition error of the high value and the low value caused by the sensor detection error can be reduced, and the detection accuracy of the model printing failure anomaly can be improved.

[0067] By the above method, the high value and the low value can be flexibly determined.

[0068] In one embodiment of the present application, the method further includes: taking the value of the time axis interval of separation as the detection value of the printing platform during the process of separation of the printing platform and the material tank, and taking the value of the time axis interval of completion of separation as the detection value of the printing platform after the printing platform and the material tank have been separated, wherein the time axis can be obtained by the motor movement of the printing platform, or by estimating the time of lifting and falling of the printing platform after exposure; or

[0069] Identify the maximum value of the detection value of the printing platform that rises and then falls during the process of lifting the printing platform, and regard the process of the detection value rising and then falling as the process of separation of the printing platform and the material trough, and regard the process after the detection value falls as the process after the printing platform and the material trough have been separated.

[0070] In this embodiment, the detection value during the process of separating the printing platform from the material tank, and the acquisition of the detection value after the printing platform and the material tank have been separated, can specifically include two embodiments:

[0071] In one embodiment, the value of the time axis during the separation process (including the average or maximum value) can be used as the detection value of the printing platform during the separation process, and the value of the time axis during the completion of the separation process (including the average or minimum value) can be used as the detection value of the printing platform after the separation process. The time axis during the separation process can be obtained by the movement of the motor of the printing platform, or by estimating the time for the printing platform to rise and fall after exposure, or other methods can be used, which are not specifically limited here.

[0072] Another embodiment is to determine whether the printing platform and the material trough are separated by identifying the trend of the detection value during the lifting process of the printing platform. For example, when the detection value during the lifting process of the printing platform is identified, when a maximum value of the detection value rises and then falls appears, the process of rising and then falling is determined as the process of separation of the printing platform and the material trough, and the process of reaching a stable state after falling is determined as the process after which the printing platform and the material trough are separated, thereby obtaining the detection value of the process of separation of the printing platform and the material trough and the detection value after the printing platform and the material trough are separated.

[0073] Through the above method, the separation between the printing platform and the material trough can be accurately determined, thereby obtaining accurate detection values ​​and improving the reliability of model printing failure detection.

[0074] In one embodiment of the present application, based on the area of ​​the currently printed model layer, one of the following methods is selected as the method for determining the second detection value: determining the lower value of the detection value of the printing platform during the process of lifting the printing platform after the model layer is exposed as the second detection value, and determining the detection value of the printing platform after the printing platform is separated from the material tank as the second detection value, including:

[0075] If the area of ​​the currently printed model layer is less than or equal to the first preset area, then in the process of lifting the printing platform after exposing the model layer, the lowest value of the detection value of the printing platform located after the first detection value on the time axis is determined as the second detection value;

[0076] If the area of ​​the currently printed model layer is larger than the first preset area, the detection value of the printing platform after the printing platform and the material tank are separated is used as the second detection value.

[0077] In this embodiment, a specific method for determining the second detection value based on the area of ​​the currently printed model layer is defined. Because the area of ​​the printed model affects the release force (larger area means greater release force, smaller area means less release force), the area of ​​the currently printed model layer is compared with the first preset area to determine the area of ​​the currently printed model layer.

[0078] If the area of ​​the currently printed model layer is larger than the first preset area, the release force generated may be relatively large. For example, for ordinary resin, the release force of a model layer with an area of ​​50mm×50mm is about 2500g. For high-speed resin, it will be lower than this value. The detection value generated when the printing platform is out of the liquid surface has no effect or very little effect on the judgment of its release. Therefore, the detection value of the printing platform after the printing platform is separated from the material tank (that is, the lifting end detection value) is used as the second detection value. In other words, the higher value of the detection value during the lifting process of the printing platform and the lifting end detection value are used to determine whether the model printing has failed.

[0079] If the area of ​​the currently printed model layer is less than or equal to the first preset area, the release force it generates may be relatively small, and the detection value generated when the printing platform emerges from the liquid surface will have a significant impact on the judgment of its release, which may lead to misjudgment. In this case, the low value generated when the printing platform is raised after the model layer is exposed is used as the second detection value. In other words, the high and low values ​​of the detection value during the lifting of the printing platform are used to determine whether the model printing has failed. Determining whether a print has failed based on the relationship between the high and low values ​​can avoid the judgment of a print failure being affected by a large detection value when the printed model emerges from the liquid surface, ensuring a more reliable judgment of a print failure.

[0080] It should be noted that, in this application, when the area of ​​the currently printed model layer is less than or equal to the first preset area, the second detection value determined is the detection value of the printing platform located after the first detection value on the time axis. That is to say, the low value at the beginning of release is not of reference value. This application uses the low value after the high value in the release process, rather than the low value at the beginning of release directly as the second detection value, thereby avoiding the low value at the beginning of release from being included, and ensuring the accuracy of the detection of model printing failure.

[0081] In one embodiment of the present application, determining, based on the magnitude relationship between the first detection value and the second detection value, that a 3D printing device has an abnormal situation in which a model printing failure occurs includes:

[0082] If the area of ​​the currently printed model layer is less than or equal to the first preset area, then when the difference between the first detection value and the second detection value is less than or equal to the first preset threshold, it is determined that an abnormal situation of model printing failure occurs in the 3D printing device;

[0083] If the area of ​​the currently printed model layer is larger than the first preset area, then when the difference between the first detection value and the second detection value is less than or equal to the second preset threshold, it is determined that the 3D printing device has an abnormal situation of model printing failure, and the first preset threshold is the same as or different from the second preset threshold.

[0084] In this embodiment, when the area of ​​the currently printed model layer is less than or equal to the first preset area, the first detection value is the high value of the detection value in the process of lifting the printing platform after the model layer is exposed, and the second detection value is the low value. The difference between the high value and the low value is calculated. If the difference is less than or equal to the first preset threshold, it indicates that the change in the detection value during the lifting process is small, and there may be a situation where there is no model on the printing platform, so there is no interaction force between the printing platform and the release film. Therefore, it is determined that the model printing has failed, with high judgment accuracy.

[0085] When the area of ​​the currently printed model layer is larger than the first preset area, the first detection value is the high value of the detection value in the process of lifting the printing platform after the model layer is exposed, and the second detection value is the detection value at the end of lifting. The difference between the high value and the detection value at the end of lifting is calculated. If the difference is less than or equal to the second preset threshold, it indicates that the change in the detection value during the lifting process is small, and there may be a situation where there is no model on the printing platform, so there is no interaction force between the printing platform and the release film. Therefore, it is judged that the model printing failed, with high judgment accuracy.

[0086] It is worth noting that since the area of ​​the model layer is less than or equal to the first preset area and the area of ​​the model layer is greater than the first preset area are two different situations, the corresponding preset thresholds for determining the difference can be different values, or of course can be the same value.

[0087] In one embodiment of the present application, the method further includes: if the area of ​​the model layer is less than or equal to a first preset area and greater than a second preset area, then when the release height of the model layer is less than the liquid level of the to-be-cured material contained in the trough and has a preset height difference with the liquid level or the release height of the model layer is less than the preset height, and the difference between the first detection value and the second detection value is less than or equal to a first preset threshold, it is determined that an abnormal situation of model printing failure occurs in the 3D printing device, and the second preset area is less than the first preset area.

[0088] In this embodiment, when the area of ​​the model layer is less than or equal to a first preset area and greater than a second preset area, the release height of the model layer is obtained. If the difference between the first detection value and the second detection value is less than or equal to a first preset threshold value, the release height of the model layer is less than the liquid level of the to-be-cured material contained in the trough and has a preset height difference from the liquid level, or the release height of the model layer is less than the preset height, then it is determined that an abnormal condition has occurred in the 3D printing device resulting in a model printing failure. The release height of the model layer is the height to which the printing platform is raised during the separation of the model from the release film. Because the above-mentioned release height of the model layer is less than the liquid level of the to-be-cured material contained in the trough and has a preset height difference from the liquid level, or the release height of the model layer is less than the preset height, the printing platform can be prevented from entering and exiting the liquid level when printing the first few layers of the model. It is understandable that when the printer prints the first few layers of the model, the model may easily fall off the bottom / break / be incomplete due to the problem of adhesion between the model and the printing platform. Therefore, the above embodiment can avoid the situation where the printing platform enters and exits the liquid surface when printing the first few layers of the model, thereby avoiding the material adsorption force caused by the platform entering and exiting the liquid surface when the printer prints the first few layers of the model. The influence of the accuracy of the release adsorption force determined by the detection value can be avoided, thereby avoiding the misjudgment of abnormal printing failures, and can improve the monitoring accuracy of printing failures when the model is more likely to fail to print, and can detect printing failures as early as possible, thereby minimizing the waste of the material to be solidified for the model.

[0089] In one embodiment of the present application, the first preset area is in a range of 45 mm × 45 mm to 55 mm × 55 mm;

[0090] The second preset area has a selection range of 10 mm×10 mm to 20 mm×20 mm;

[0091] The preset height is less than the liquid level of the material to be solidified contained in the trough;

[0092] The selected value range of the liquid level height is 15mm to 20mm.

[0093] In this embodiment, the first preset area ranges from 45mm×45mm to 55mm×55mm, for example, 50mm×50mm. Specifically, a model layer larger than 45mm×45mm to 55mm×55mm is considered a larger model layer, while a model layer smaller than 45mm×45mm to 55mm×55mm is considered a smaller model layer. Model layers with larger areas generally have greater release adhesion during release. During the release process, the added effect of the material adhesion force caused by the platform entering and exiting the liquid surface on the release adhesion is minimal. Therefore, determining a printing abnormality based on the first detection value minus the lift end detection value < the preset threshold is more accurate, and the likelihood of falsely determining a printing failure is lower, thereby improving the software's judgment speed and avoiding false positives. However, a model layer with a smaller area generally has a smaller release force due to its small area. During the release process, if the material adsorption force brought by the platform entering and exiting the liquid surface is superimposed on the release adsorption force, it will have a greater impact on the overall value of the detection value. At this time, if the printing abnormality is still determined based on the first detection value - the lifting end detection value < the preset threshold, there will be a certain misjudgment rate. Therefore, the high value of the detection value of the printing platform during the process of lifting the printing platform after the model layer is exposed is used as the first detection value, and the low value of the detection value of the printing platform during the process of lifting the printing platform after the model layer is exposed is used as the second detection value. When the difference between the first detection value and the second detection value is less than or equal to the preset threshold, it is determined that the model printing has failed. This can avoid the influence of the peak value of the material adsorption force on the judgment of model printing failure, thereby improving the accuracy of the judgment of model printing failure.

[0094] The selection range of the second preset area is 10mm×10mm to 20mm×20mm, for example, 15mm×15mm. The lower limit of the model layer area is set, that is, the second preset area. It is necessary to judge the release force when the model layer area is larger than this value to avoid unreliable detection of abnormal conditions such as bottom falling due to too small an area.

[0095] The liquid level of the material to be cured in the trough is selected to be in the range of 15 mm to 20 mm, for example, 18 mm. This setting prevents the liquid level from being too high, causing the material to flow too quickly on the substrate, generating bubbles or forming an uneven model layer. It also prevents the liquid level from being too low, causing the material to not fully penetrate the substrate, resulting in a defective or incomplete model layer.

[0096] The preset height is less than the liquid level of the to-be-cured material contained within the trough, and can also be less than 15mm to 20mm. In some embodiments, the release height of the model layer can be set to less than 12mm, for example, 8mm. By setting the release height less than the liquid level of the to-be-cured material contained within the trough, or by setting the release height of the model layer less than the preset height, the impact of the printing platform entering and exiting the liquid can be eliminated. At the same time, the release height of the model layer should not be too small to avoid problems such as insufficient lifting height leading to release failure.

[0097] In one embodiment of the present application, the detection value includes a detection value obtained during the lifting process of each printing platform when continuously printing multiple model layers; determining an abnormal situation in which the 3D printing device fails to print the model based on the relationship between the first detection value and the second detection value includes:

[0098] If the area of ​​the currently printed model layer is less than or equal to the first preset area, then when the difference between the first detection value and the second detection value of a first number of consecutive model layers is less than or equal to a first preset threshold, it is determined that an abnormal situation of model printing failure occurs in the 3D printing device;

[0099] If the area of ​​the currently printed model layer is larger than the first preset area, then when the difference between the first detection value and the second detection value of a second number of consecutive model layers is less than or equal to a second preset threshold, it is determined that an abnormal situation of model printing failure occurs in the 3D printing device, wherein the first number is larger than the second number, and the first preset threshold is the same as or different from the second preset threshold.

[0100] In this embodiment, whether a model printing failure has occurred is determined by determining whether a plurality of consecutive model layers meet the printing failure determination criteria. Specifically, if the area of ​​the model layer is less than or equal to a first predetermined area, the model printing is considered to have failed if a first number of consecutive model layers meet the printing failure determination criteria. If the area of ​​the model layer is greater than the first predetermined area, the model printing is considered to have failed if a second number of consecutive model layers meet the printing failure determination criteria.

[0101] The number of continuous model layers corresponding to different area conditions is different, for example, the first number is greater than the second number. Because when the area is small, the increase and decrease in the release force are not obvious, and the probability of misjudgment is relatively high, using more model layers for more accurate judgment is more accurate. When the area of ​​the model layer is less than or equal to the first preset area, judging the accuracy of the print failure judgment by the first number of model layers can be improved. When the area is large, the increase and decrease in the release force are obvious, and the probability of misjudgment is low, so fewer model layers can achieve an accurate judgment. When the area of ​​the model layer is greater than the first preset area, judging the efficiency of the print failure judgment by the second number of model layers can be improved.

[0102] In addition, the printing area of ​​the model base is usually large, but the area of ​​the model supported by the base may be reduced. Therefore, if the area is large and too many layers are set, it is not conducive to judging whether the base is printed or not.

[0103] In one embodiment of the present application, depending on whether the printing platform passes through the liquid surface during the process of lifting the printing platform after the model layer is exposed, one of the following methods is selected as the method for determining the second detection value: determining the lower value of the detection value of the printing platform during the process of lifting the printing platform after the model layer is exposed as the second detection value, and determining the detection value of the printing platform after the printing platform is separated from the material tank as the second detection value, including:

[0104] Determine whether the printing platform passes through the liquid surface during the process of lifting the printing platform after the model layer is exposed;

[0105] If the printing platform passes through the liquid surface during the process of lifting the printing platform after the model layer is exposed, the lowest detection value of the printing platform located after the first detection value on the time axis during the process of lifting the printing platform after the model layer is exposed is determined as the second detection value;

[0106] If the printing platform does not pass through the liquid surface during the process of lifting the printing platform after the model layer is exposed, the detection value of the printing platform after the printing platform and the material tank are separated is used as the second detection value.

[0107] In this embodiment, a specific method for determining the second detection value is defined based on whether the printing platform passes through the liquid surface during the process of raising the printing platform after the model layer is exposed. If the printing platform does not pass through the liquid surface during the process of raising the printing platform after the model layer is exposed, the problem of the material adsorption force when the printing platform emerges from the liquid surface superimposed on the detection value used to monitor the release adsorption force will not exist, thus reducing the probability of false positives. Therefore, the detection value of the printing platform after separation from the material tank (i.e., the detection value at the end of the lifting) is used as the second detection value. In other words, the higher value of the detection value during the lifting process and the detection value at the end of the lifting process are used to determine whether the model printing has failed.

[0108] If the printing platform passes through the liquid surface during the process of lifting the printing platform after the model layer is exposed, there may be a problem where the material adsorption force when the printing platform emerges from the liquid surface is superimposed and affects the detection value used to monitor the release adsorption force, thereby causing the problem of misjudging the model printing abnormality. In this case, the low value during the process of lifting the printing platform after the model layer is exposed is used as the second detection value, that is, the high and low values ​​of the detection values ​​during the process of lifting the printing platform are used to determine whether the model printing has failed. Determining whether the printing has failed based on the relationship between the high and low values ​​can avoid the false judgment of model printing failure caused by the greater material adsorption force when the printed model emerges from the liquid surface affecting the detection value at the end of the lifting, ensuring that the judgment of printing failure is more accurate and reliable.

[0109] It should be noted that, in some embodiments, when the printing platform passes through the liquid surface during the process of lifting the printing platform after the model layer is exposed, the second detection value determined is the detection value of the printing platform that is located after the first detection value on the time axis. That is to say, the low value at the beginning of release is not of reference value. This embodiment uses the low value after the high value in the release process, rather than the low value at the beginning of release directly as the second detection value, thereby avoiding the low value at the beginning of release from being included, thereby ensuring the accuracy of detection of model printing failure.

[0110] In one embodiment of the present application, determining whether the printing platform passes through the liquid surface during the process of lifting the printing platform after the model layer is exposed includes:

[0111] If, during the process of raising the printing platform, the detection value of the printing platform shows a trend of first rising, then falling, then rising again, and then falling again, it is determined that the printing platform passes through the liquid surface during the process of raising the printing platform after the model layer is exposed; or

[0112] Obtain the position range of the printing platform's movement during the lifting process, and obtain the liquid level height of the material tank during the lifting process. Then, based on the position range and liquid level height, determine whether the printing platform passes through the liquid surface during the lifting process after the model layer is exposed.

[0113] In this embodiment, the method of determining whether the printing platform passes through the liquid surface during the process of lifting the printing platform after the model layer is exposed may specifically include two embodiments:

[0114] In one embodiment, if the detection value of the printing platform shows a trend of first rising, then falling, then rising again, and then falling again during the process of lifting the printing platform, it is determined that the printing platform passes through the liquid surface during the process of lifting the printing platform after the model layer is exposed. Figure 2As shown, the curve of the test value of the printing platform shows a trend of rising, falling, rising again, and falling again, with two peaks. The first peak a mainly reflects the release adsorption force of the release film on the model carried by the printing platform when the model is separated from the release film in the material tank. The maximum value of the test value can basically reflect the maximum value of the release adsorption force. The second peak b mainly reflects the material adsorption force of the to-be-cured material in the material tank on the printing platform when the printing platform emerges from the liquid surface. This material adsorption force is relatively large. Therefore, after the model carried by the printing platform has separated from the release film (that is, after the release is completed), it is likely that the release adsorption force, which is basically close to 0, is superimposed on the relatively large material adsorption force, resulting in a relatively large overall test value, resulting in a maximum value of the material adsorption force. The second peak b, i.e., the maximum value of the test value, can basically reflect the maximum value of the above-mentioned material adsorption force. The print platform's detection value shows a trend of rising, falling, rising again, and falling again, indicating that the print platform's detection value presents two spaced maxima. Therefore, it can be deduced that the force acting on the print platform passes through the maximum release adsorption force and the maximum material adsorption force at a certain time interval. Therefore, it can be accurately determined that the print platform has passed the liquid surface. In this way, based on the changes in the print platform's detection value, it is possible to accurately determine whether the print platform has passed the liquid surface during the process of lifting the print platform after the model layer is exposed.

[0115] In a specific embodiment, the trend of first rising, then falling, then rising, then falling is a trend in which at least a third number of test values ​​rise in a row, then at least a fourth number of test values ​​fall in a row, then at least a fifth number of test values ​​rise in a row, and then at least a sixth number of test values ​​fall in a row. In one example, the third number, the fourth number, the fifth number, and the sixth number are all 1. In another example, the third number, the fourth number, the fifth number, and the sixth number are all natural numbers greater than 1. In another example, the third number, the fourth number, the fifth number, and the sixth number are all natural numbers greater than zero. In yet another example, the third number, the fourth number, the fifth number, and the sixth number are all natural numbers greater than or equal to 5. The third number, the fourth number, the fifth number, and the sixth number can be all the same, two different numbers, or partially the same.

[0116] Another embodiment is to obtain the position range of the movement of the printing platform and the liquid level height of the material tank during the lifting of the printing platform, and then determine whether the printing platform passes through the liquid surface during the process of lifting the printing platform after the model layer is exposed by comparing the position range and the liquid level height.

[0117] Among them, the position interval of the movement of the printing platform can be determined by the sum of the initial release height of the printing platform and the model height of the printing platform during the lifting process of the printing platform, and the sum of the final release height of the printing platform and the model height of the printing platform, that is, the position interval of the movement of the printing platform is the position interval between the sum of the first height and the sum of the second height. The sum of the first height is the sum of the initial release height and the model height of the printing platform, and the sum of the second height is the sum of the final release height and the model height of the printing platform. The initial release height refers to the height of the printing platform when the printing platform just starts to release, and this height can be 0 (and the height zero point of this height can be the bottom of the material trough), that is, the printing platform is located on the bottom of the material trough. The final release height refers to the height of the printing platform after the printing platform has completed the release. This height can be the required release height of the model layer provided in the model's slicing file. The 3D printing device will control the corresponding distance of the printing platform lift according to the release height provided in the slicing file. The final release height can also be: during the platform lifting and releasing process of each layer of model printing, the detection value used to characterize the force condition of the printing platform is detected in real time, and after determining that the printing platform has completed the release action through the changing trend of the detection value during the platform lifting and releasing process, the printing platform is controlled to stop lifting, and the height of the position where the printing platform stops lifting is recorded, and the height of the position where the printing platform stops lifting is used as the final release height.

[0118] Alternatively, the position interval of the printing platform movement can be directly determined according to the position of the motor for the printing platform movement.

[0119] After obtaining the position range of the print platform's movement, the liquid level in the trough is compared with this position range to determine whether the liquid level in the trough is within this position range. If the liquid level in the trough is within this position range, it indicates that the print platform has been lifted over the liquid surface in the trough; if the liquid level in the trough is not within this position range, it indicates that the print platform has not been lifted over the liquid surface in the trough.

[0120] Through the above method, it is possible to accurately determine whether the printing platform passes through the liquid surface during the process of lifting the printing platform after the model layer is exposed, thereby improving the detection effect of model printing failure.

[0121] In one embodiment of the present application, during the process of raising the printing platform, obtaining a detection value used to characterize the force condition of the printing platform includes:

[0122] The highest value of the detection value of the printing platform during the process of the printing platform being lifted is used as the third detection value;

[0123] The detection value includes a third detection value, and judging whether the 3D printing device has an abnormal situation of model printing failure based on the detection value includes:

[0124] If the third detection value is less than or equal to the third preset threshold, it is determined that an abnormal situation occurs in the 3D printing device where the model printing fails.

[0125] In this embodiment, the force applied to the print platform is detected during its lift, and a third detection value is obtained during the lift. This third detection value is the highest value during the lift, typically occurring when the model on the print platform separates from the release film, such as at the moment of separation. Furthermore, the third detection value is compared with a third preset threshold. If the third detection value is less than or equal to the third preset threshold, it indicates that the detection value during release was too low, possibly indicating a printing failure.

[0126] The present application also provides a 3D printing device, which includes:

[0127] A material trough, for containing the material to be cured;

[0128] A printing platform, used to carry the printed model, and the printing platform moves relative to the material trough to realize model printing;

[0129] a memory storing programs or instructions;

[0130] The processor implements the various steps of the embodiment of the printing abnormality detection method of the 3D printing device when executing the program or instruction, and can achieve the same technical effect. To avoid repetition, it is not repeated here.

[0131] The memory can be used to store software programs and various data. The memory may mainly include a first storage area for storing programs or instructions and a second storage area for storing data, wherein the first storage area may store an operating system, applications or instructions required for at least one function (such as a sound playback function, an image playback function, etc.), etc. In addition, the memory may include a volatile memory or a non-volatile memory, or the memory may include both volatile and non-volatile memories. Among them, the non-volatile memory may be a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), or a flash memory. The volatile memory may be a random access memory (RAM), a static random access memory (SRAM), a dynamic random access memory (DRAM), a synchronous dynamic random access memory (SDRAM), a double data rate synchronous dynamic random access memory (DDRSDRAM), an enhanced synchronous dynamic random access memory (ESDRAM), a synchronous link dynamic random access memory (SLDRAM), and a direct memory bus random access memory (DRRAM). The memory in the embodiments of the present application includes but is not limited to these and any other suitable types of memory.

[0132] The processor may include one or more processing units; optionally, the processor may integrate an application processor and a modem processor, wherein the application processor primarily handles operations related to the operating system, user interface, and application programs, and the modem processor primarily processes wireless communication signals, such as a baseband processor. It is understood that the modem processor may not be integrated into the processor.

[0133] An embodiment of the present application further provides a readable storage medium having a program or instruction stored thereon. When the program or instruction is executed by a processor, the various processes of the embodiment of the printing abnormality detection method for the above-mentioned 3D printing device are implemented, and the same technical effect can be achieved. To avoid repetition, they are not described here.

[0134] The present application also provides the following embodiments:

[0135] Reference number 1, an embodiment of the present application provides a method for detecting printing anomalies in a 3D printing device, wherein the 3D printing device includes a printing platform and a material trough, and the method includes:

[0136] Controlling the printing platform to lift in a vertical direction to drive the model layer on the printing platform to separate from the release film at the bottom of the trough;

[0137] During the process of raising the printing platform, obtaining a detection value for characterizing a force condition of the printing platform;

[0138] According to the detection value, it is determined whether an abnormal situation of model printing failure occurs in the 3D printing device.

[0139] Reference numeral 2, based on reference numeral 1, the detection value includes a first detection value and a second detection value, and judging whether an abnormal situation of model printing failure occurs in the 3D printing device according to the detection values ​​includes:

[0140] Based on the magnitude relationship between the first detection value and the second detection value, it is determined that an abnormal situation of model printing failure occurs in the 3D printing device, where the first detection value and the second detection value are detection values ​​obtained at different time points or different time intervals during the process of lifting the printing platform, where different time intervals overlap or do not overlap with each other.

[0141] Reference numeral 3, based on reference numeral 2, determining that an abnormal situation of model printing failure occurs in the 3D printing device according to the magnitude relationship between the first detection value and the second detection value, including:

[0142] When the first detection value and the second detection value meet a preset condition, determining that an abnormal situation of model printing failure occurs in the 3D printing device;

[0143] Among them, the preset conditions include one or more of the following conditions: the difference between the first detection value and the second detection value is less than or equal to a preset threshold, the absolute value of the difference between the first detection value and the second detection value is less than or equal to a preset threshold, the change slope of the first detection value and the second detection value with respect to the time axis is less than a preset change slope, and the ratio of the first detection value to the second detection value is within a preset ratio range.

[0144] Reference numeral 4, based on reference numeral 3, the detection value includes the detection value obtained during the lifting process of the printing platform when printing a model layer, or the detection value obtained during the lifting process of each printing platform when printing multiple model layers continuously;

[0145] When the first detection value and the second detection value meet a preset condition, determining that the 3D printing device has an abnormal situation in which the model printing fails includes:

[0146] When the first detection value and the second detection value of one of the model layers meet the preset condition, determining that an abnormal situation of model printing failure occurs in the 3D printing device; or

[0147] When the first detection values ​​and the second detection values ​​of a plurality of consecutive model layers all meet the preset condition, it is determined that an abnormal situation of model printing failure occurs in the 3D printing device.

[0148] Reference number 5, based on reference number 2, obtaining the first detection value and the second detection value, including:

[0149] The higher value of the detection value of the printing platform during the process of lifting the printing platform after the model layer is exposed is used as the first detection value, and the lower value of the detection value of the printing platform during the process of lifting the printing platform after the model layer is exposed is used as the second detection value; or

[0150] using the detection value of the printing platform during the process of separating the printing platform from the material trough as the first detection value, and using the detection value of the printing platform after the printing platform is separated from the material trough as the second detection value; or

[0151] The high value of the detection value of the printing platform during the process of lifting the printing platform after the model layer is exposed is used as the first detection value, and according to the area of ​​the currently printed model layer, one of the following methods is selected as the method for determining the second detection value: the low value of the detection value of the printing platform during the process of lifting the printing platform after the model layer is exposed is determined as the second detection value, and the detection value of the printing platform after the printing platform and the material trough are separated is used as the second detection value;

[0152] The highest value of the detection value of the printing platform in the process of lifting the printing platform after the model layer is exposed is used as the first detection value, and according to whether the printing platform passes through the liquid surface in the process of lifting the printing platform after the model layer is exposed, one of the following methods is selected as the method for determining the second detection value: the lowest value of the detection value of the printing platform in the process of lifting the printing platform after the model layer is exposed is determined as the second detection value, and the detection value of the printing platform after the printing platform and the material trough are separated is used as the second detection value.

[0153] Reference number 6, based on reference number 5, the high value includes one or more values; the low value includes one or more values;

[0154] When the high value includes a value, the high value is a maximum value of the detection value of the printing platform during the process of lifting the printing platform; when the low value includes a value, the low value is a minimum value of the detection value of the printing platform during the process of lifting the printing platform; or

[0155] When the high value includes multiple values, the average of the multiple high values ​​is used as the first detection value; when the low value includes multiple values, the average of the multiple low values ​​is used as the second detection value.

[0156] Reference number 7, based on reference number 5, the method further includes:

[0157] The value of the time axis interval of the release is taken as the detection value of the printing platform during the process of separating the printing platform from the material tank, and the value of the time axis interval of the completion of the release is taken as the detection value of the printing platform after the printing platform and the material tank have been separated, wherein the time axis can be obtained by the motor movement of the printing platform, or by estimating the time of lifting and falling of the printing platform after exposure; or

[0158] Identify the maximum value of the detection value of the printing platform that rises and then falls during the process of lifting the printing platform, and regard the process of the detection value rising and then falling as the process of separation of the printing platform from the material trough, and regard the process after the detection value falls as the process after the printing platform and the material trough have been separated.

[0159] Reference numeral 8, based on reference numeral 5, selecting one of the following methods as a method for determining the second detection value based on the area of ​​the currently printed model layer: determining the second detection value by taking a lower value of the detection value of the printing platform during the process of lifting the printing platform after the model layer is exposed, or determining the second detection value by taking a detection value of the printing platform after the printing platform is separated from the material trough, including:

[0160] If the area of ​​the currently printed model layer is less than or equal to the first preset area, then in the process of lifting the printing platform after exposing the model layer, the lowest value of the detection value of the printing platform located after the first detection value on the time axis is determined as the second detection value;

[0161] If the area of ​​the currently printed model layer is larger than the first preset area, the detection value of the printing platform after the printing platform and the material trough are separated is used as the second detection value.

[0162] Reference numeral 9, based on reference numeral 8, determining that an abnormal situation of model printing failure occurs in the 3D printing device according to the magnitude relationship between the first detection value and the second detection value, includes:

[0163] If the area of ​​the currently printed model layer is less than or equal to the first preset area, then when the difference between the first detection value and the second detection value is less than or equal to a first preset threshold, it is determined that an abnormal situation of model printing failure occurs in the 3D printing device;

[0164] If the area of ​​the currently printed model layer is larger than the first preset area, then when the difference between the first detection value and the second detection value is less than or equal to a second preset threshold, it is determined that an abnormal situation of model printing failure occurs in the 3D printing device, and the first preset threshold is the same as or different from the second preset threshold.

[0165] Reference number 10, based on reference number 9, the method further includes:

[0166] If the area of ​​the model layer is less than or equal to the first preset area and greater than the second preset area, then when the release height of the model layer is less than the liquid level of the to-be-cured material contained in the trough and has a preset height difference from the liquid level or the release height of the model layer is less than the preset height, and the difference between the first detection value and the second detection value is less than or equal to a first preset threshold, it is determined that an abnormal situation of model printing failure occurs in the 3D printing device, and the second preset area is less than the first preset area.

[0167] Reference number 11, based on reference number 10, the value range of the first preset area is 45 mm×45 mm to 55 mm×55 mm;

[0168] The second preset area has a value range of 10 mm×10 mm to 20 mm×20 mm;

[0169] The preset height is less than the liquid level of the material to be solidified contained in the trough;

[0170] The selected value range of the liquid level height is 15 mm to 20 mm.

[0171] Reference numeral 12, based on reference numeral 8, the detection value includes the detection value obtained during each lifting process of the printing platform when printing multiple model layers continuously;

[0172] The determining, based on the magnitude relationship between the first detection value and the second detection value, that the 3D printing device has an abnormal situation in which the model printing fails, includes:

[0173] If the area of ​​the currently printed model layer is less than or equal to a first preset area, then when the difference between the first detection value and the second detection value of a first number of consecutive model layers is less than or equal to a first preset threshold, it is determined that an abnormal situation of model printing failure occurs in the 3D printing device;

[0174] If the area of ​​the currently printed model layer is larger than the first preset area, then when the difference between the first detection value and the second detection value of a second number of consecutive model layers is less than or equal to a second preset threshold, it is determined that an abnormal situation of model printing failure occurs in the 3D printing device, wherein the first number is larger than the second number, and the first preset threshold is the same as or different from the second preset threshold.

[0175] Reference numeral 13, based on reference numeral 5, selecting one of the following methods as a method for determining the second detection value, based on whether the printing platform passes through the liquid surface during the process of lifting the printing platform after the model layer is exposed: determining the lower value of the detection value of the printing platform during the process of lifting the printing platform after the model layer is exposed as the second detection value, and determining the detection value of the printing platform after the printing platform is separated from the material tank as the second detection value, including:

[0176] determining whether the printing platform passes through a liquid surface during the process of lifting the printing platform after the model layer is exposed;

[0177] If the printing platform passes through the liquid surface during the process of lifting the printing platform after the model layer is exposed, a lower value of the detection value of the printing platform located after the first detection value on the time axis during the process of lifting the printing platform after the model layer is exposed is determined as the second detection value;

[0178] If the printing platform does not pass through the liquid surface during the process of lifting the printing platform after the model layer is exposed, the detection value of the printing platform after the printing platform is separated from the material tank is used as the second detection value.

[0179] Reference numeral 14, based on reference numeral 13, determining whether the printing platform passes through the liquid surface during the process of lifting the printing platform after the model layer is exposed includes:

[0180] If, during the process of raising the printing platform, the detection values ​​of the printing platform show a trend of first rising, then falling, then rising, then falling, then the printing platform is determined to have passed through the liquid surface during the process of raising the printing platform after the model layer is exposed; the trend of first rising, then falling, then rising, then falling is a trend of first at least a third number of detection values ​​rising, then at least a fourth number of detection values ​​falling, then at least a fifth number of detection values ​​rising, then at least a sixth number of detection values ​​falling; or,

[0181] Obtain the position interval of the movement of the printing platform during the lifting of the printing platform, and obtain the liquid level height of the material tank during the lifting of the printing platform. Then, determine whether the printing platform passes through the liquid surface during the lifting of the printing platform after the model layer is exposed through the position interval and the liquid level height.

[0182] Reference numeral 15, based on reference numeral 1 or any of the above embodiments, the abnormal situation of model printing failure includes one or more of the following situations: model bottom falling, model damage, and model fracture; and the detection value used to characterize the force condition of the printing platform during the process of raising the printing platform includes:

[0183] taking a higher value of the detection value of the printing platform during the process of the printing platform being lifted as a third detection value;

[0184] The detection value includes a third detection value, and judging whether an abnormal situation of model printing failure occurs in the 3D printing device based on the detection value includes:

[0185] If the third detection value is less than or equal to a third preset threshold, it is determined that an abnormal situation occurs in the 3D printing device where the model printing fails.

[0186] The embodiments of the present application are described above in conjunction with the accompanying drawings, but the present application is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of this application, ordinary technicians in this field can also make many forms without departing from the purpose of this application and the scope of protection of the claims, all of which are within the protection of this application.

Claims

1. A method for detecting printing anomalies in a 3D printing device, characterized in that: The 3D printing device includes a printing platform and a material trough, and the method includes: Controlling the printing platform to lift in a vertical direction to drive the model layer on the printing platform to separate from the release film at the bottom of the trough; During the process of raising the printing platform, obtaining a detection value for characterizing a force condition of the printing platform; According to the detection value, it is determined whether an abnormal situation of model printing failure occurs in the 3D printing device.

2. The method according to claim 1, characterized in that The detection values ​​include a first detection value and a second detection value, and judging whether an abnormal situation of model printing failure occurs in the 3D printing device based on the detection values ​​includes: Determining, based on a magnitude relationship between the first detection value and the second detection value, that the 3D printing device has an abnormal situation in which the model printing fails, the first detection value and the second detection value being detection values ​​obtained at different time points or in different time intervals during the process of raising the printing platform, wherein the different time intervals may overlap or not overlap with each other; The determining, based on the magnitude relationship between the first detection value and the second detection value, that the 3D printing device has an abnormal situation in which the model printing fails, includes: When the first detection value and the second detection value meet a preset condition, determining that an abnormal situation of model printing failure occurs in the 3D printing device; The preset conditions include one or more of the following conditions: the difference between the first detection value and the second detection value is less than or equal to a preset threshold, the absolute value of the difference between the first detection value and the second detection value is less than or equal to a preset threshold, the change slope of the first detection value and the second detection value with respect to the time axis is less than a preset change slope, and the ratio of the first detection value to the second detection value is within a preset ratio range; The detection value includes a detection value obtained during the lifting process of the printing platform when printing one model layer, or a detection value obtained during the lifting process of each printing platform when printing multiple model layers continuously; When the first detection value and the second detection value meet a preset condition, determining that the 3D printing device has an abnormal situation in which the model printing fails includes: When the first detection value and the second detection value of one of the model layers meet the preset condition, determining that an abnormal situation of model printing failure occurs in the 3D printing device; or When the first detection values ​​and the second detection values ​​of a plurality of consecutive model layers all meet the preset condition, it is determined that an abnormal situation of model printing failure occurs in the 3D printing device.

3. The method according to claim 2, characterized in that Obtaining the first detection value and the second detection value includes: The higher value of the detection value of the printing platform during the process of lifting the printing platform after the model layer is exposed is used as the first detection value, and the lower value of the detection value of the printing platform during the process of lifting the printing platform after the model layer is exposed is used as the second detection value; or using the detection value of the printing platform during the process of separating the printing platform from the material trough as the first detection value, and using the detection value of the printing platform after the printing platform is separated from the material trough as the second detection value; or The high value of the detection value of the printing platform during the process of lifting the printing platform after the model layer is exposed is used as the first detection value, and according to the area of ​​the currently printed model layer, one of the following methods is selected as the method for determining the second detection value: the low value of the detection value of the printing platform during the process of lifting the printing platform after the model layer is exposed is determined as the second detection value, and the detection value of the printing platform after the printing platform and the material trough are separated is used as the second detection value; The higher value of the detection value of the printing platform during the process of lifting the printing platform after the model layer is exposed is used as the first detection value, and according to whether the printing platform passes through the liquid surface during the process of lifting the printing platform after the model layer is exposed, one of the following methods is selected as the method for determining the second detection value: the lower value of the detection value of the printing platform during the process of lifting the printing platform after the model layer is exposed is determined as the second detection value, and the detection value of the printing platform after the printing platform and the material tank are separated is used as the second detection value; The high value includes one or more values; the low value includes one or more values; When the high value includes a value, the high value is a maximum value of the detection value of the printing platform during the process of lifting the printing platform; when the low value includes a value, the low value is a minimum value of the detection value of the printing platform during the process of lifting the printing platform; or When the high value includes multiple values, the average value of the multiple high values ​​is used as the first detection value; when the low value includes multiple values, the average value of the multiple low values ​​is used as the second detection value; The method further comprises: The value of the time axis interval of the release is taken as the detection value of the printing platform during the process of separating the printing platform from the material tank, and the value of the time axis interval of the completion of the release is taken as the detection value of the printing platform after the printing platform and the material tank have been separated, wherein the time axis can be obtained by the motor movement of the printing platform, or by estimating the time of lifting and falling of the printing platform after exposure; or Identify the maximum value of the detection value of the printing platform that rises and then falls during the process of lifting the printing platform, and regard the process of the detection value rising and then falling as the process of separation of the printing platform from the material trough, and regard the process after the detection value falls as the process after the printing platform and the material trough have been separated.

4. The method according to claim 3, characterized in that According to the area of ​​the currently printed model layer, one of the following methods is selected as the method for determining the second detection value: determining the lowest value of the detection value of the printing platform during the process of lifting the printing platform after the model layer is exposed as the second detection value, and determining the detection value of the printing platform after the printing platform is separated from the material trough as the second detection value, including: If the area of ​​the currently printed model layer is less than or equal to the first preset area, then in the process of lifting the printing platform after exposing the model layer, the lowest value of the detection value of the printing platform located after the first detection value on the time axis is determined as the second detection value; If the area of ​​the currently printed model layer is larger than the first preset area, the detection value of the printing platform after the printing platform and the material trough are separated is used as the second detection value; The determining, based on the magnitude relationship between the first detection value and the second detection value, that the 3D printing device has an abnormal situation in which the model printing fails, includes: If the area of ​​the currently printed model layer is less than or equal to the first preset area, then when the difference between the first detection value and the second detection value is less than or equal to a first preset threshold, it is determined that an abnormal situation of model printing failure occurs in the 3D printing device; If the area of ​​the currently printed model layer is larger than the first preset area, then when the difference between the first detection value and the second detection value is less than or equal to a second preset threshold, it is determined that an abnormal situation of model printing failure occurs in the 3D printing device, and the first preset threshold is the same as or different from the second preset threshold; The method further comprises: If the area of ​​the model layer is less than or equal to the first preset area and greater than the second preset area, then when the release height of the model layer is less than the liquid level of the to-be-cured material contained in the trough and has a preset height difference from the liquid level or the release height of the model layer is less than the preset height, and the difference between the first detection value and the second detection value is less than or equal to a first preset threshold, it is determined that an abnormal situation of model printing failure occurs in the 3D printing device, and the second preset area is less than the first preset area; The first preset area has a selection range of 45 mm × 45 mm to 55 mm × 55 mm; The second preset area has a value range of 10 mm × 10 mm to 20 mm × 20 mm; The preset height is less than the liquid level of the material to be solidified contained in the trough; The selected value range of the liquid level height is 15 mm to 20 mm.

5. The method according to claim 4, characterized in that The detection values ​​include detection values ​​obtained during the lifting process of each printing platform when printing multiple model layers continuously; The determining, based on the magnitude relationship between the first detection value and the second detection value, that the 3D printing device has an abnormal situation in which the model printing fails, includes: If the area of ​​the currently printed model layer is less than or equal to a first preset area, then when the difference between the first detection value and the second detection value of a first number of consecutive model layers is less than or equal to a first preset threshold, it is determined that an abnormal situation of model printing failure occurs in the 3D printing device; If the area of ​​the currently printed model layer is larger than the first preset area, then when the difference between the first detection value and the second detection value of a second number of consecutive model layers is less than or equal to a second preset threshold, it is determined that an abnormal situation of model printing failure occurs in the 3D printing device, wherein the first number is larger than the second number, and the first preset threshold is the same as or different from the second preset threshold.

6. The method according to claim 3, characterized in that According to whether the printing platform passes through the liquid surface during the process of lifting the printing platform after the model layer is exposed, one of the following methods is selected as the method for determining the second detection value: determining the lower value of the detection value of the printing platform during the process of lifting the printing platform after the model layer is exposed as the second detection value, and determining the detection value of the printing platform after the printing platform is separated from the material tank as the second detection value, including: determining whether the printing platform passes through a liquid surface during the process of lifting the printing platform after the model layer is exposed; If the printing platform passes through the liquid surface during the process of lifting the printing platform after the model layer is exposed, a lower value of the detection value of the printing platform located after the first detection value on the time axis during the process of lifting the printing platform after the model layer is exposed is determined as the second detection value; If the printing platform does not pass through the liquid surface during the process of lifting the printing platform after the model layer is exposed, the detection value of the printing platform after the printing platform is separated from the material tank is used as the second detection value.

7. The method according to claim 6, characterized in that The determining whether the printing platform passes through the liquid surface during the process of lifting the printing platform after the model layer is exposed includes: If, during the process of raising the printing platform, the detection values ​​of the printing platform show a trend of first rising, then falling, then rising, then falling, then the printing platform is determined to have passed through the liquid surface during the process of raising the printing platform after the model layer is exposed; the trend of first rising, then falling, then rising, then falling is a trend of first at least a third number of detection values ​​rising, then at least a fourth number of detection values ​​falling, then at least a fifth number of detection values ​​rising, then at least a sixth number of detection values ​​falling; or, Obtain the position interval of the movement of the printing platform during the lifting of the printing platform, and obtain the liquid level height of the material tank during the lifting of the printing platform. Then, determine whether the printing platform passes through the liquid surface during the lifting of the printing platform after the model layer is exposed through the position interval and the liquid level height.

8. The method according to any one of claims 1 to 7, characterized in that The abnormal situation in which the model printing fails includes one or more of the following situations: the model bottom falls off, the model is incomplete, and the model is broken; during the process of raising the printing platform, obtaining the detection value used to characterize the stress condition of the printing platform includes: taking a higher value of the detection value of the printing platform during the process of the printing platform being lifted as a third detection value; The detection value includes a third detection value, and judging whether an abnormal situation of model printing failure occurs in the 3D printing device based on the detection value includes: If the third detection value is less than or equal to a third preset threshold, it is determined that an abnormal situation occurs in the 3D printing device where the model printing fails.

9. A 3D printing device, characterized in that: include: A material trough, for containing the material to be cured; A printing platform, used to carry the printed model, and the printing platform moves relative to the material trough to realize model printing; a memory storing programs or instructions; A processor, wherein when executing the program or instruction, the processor implements the steps of the printing abnormality detection method for a 3D printing device according to any one of claims 1 to 8.

10. A readable storage medium having a program or instruction stored thereon, characterized in that: When the program or instruction is executed by a processor, the steps of the printing abnormality detection method for a 3D printing device according to any one of claims 1 to 8 are implemented.

Images