Fault monitoring device, method and 3D printing system and fault monitoring method thereof

Abstract

The application discloses a kind of fault monitoring equipment, method and 3D printing system and its fault monitoring method, it is related to 3D printing technical field.The present application obtains model printing information;Setting the movement mode of control component and the acquisition mode of camera;Obtain the image of monitored area;The fault feature of monitored area image is calculated, and the fault characteristic value is obtained;According to fault characteristic value, it is judged whether printing error occurs;If printing error occurs, error alarm is sent.The method can monitor the printing failure caused by the lack of material problem that 3D printing equipment may exist in printing process due to nozzle blockage, material breakage and the like, reduce the waste of material and the waste of printing time.

Description

Technical Field

[0001] This invention relates to the field of 3D printing technology, specifically to a fault monitoring device, method, and 3D printing system and its fault monitoring method. Background Technology

[0002] 3D printing equipment employs a layered manufacturing method using fused filament deposition modeling, where a filament of thermoplastic material is heated and melted, then extruded through a nozzle equipped with a micro-nozzle. During operation, based on model data, a computer controls the nozzle and 3D printing substrate to move along a preset path, working in conjunction with the nozzle's extrusion of the filament to build up material layer by layer, ultimately completing the printing of the model. Throughout the lengthy 3D printing process, filament breakage and nozzle clogging are common problems. If these issues are not detected promptly, they can damage both the model and the 3D printing platform, wasting 3D printing material and printing time.

[0003] Therefore, there is an urgent need for a technical method to quickly monitor and diagnose faults during the 3D printing process. Summary of the Invention

[0004] The purpose of this invention is to provide a fault monitoring device, method, and 3D printing system and fault monitoring method thereof to solve the problems in the background art.

[0005] Firstly, this invention provides a fault monitoring device applied to a 3D printing equipment. The 3D printing equipment includes a nozzle and a substrate. The nozzle moves along the X and Y directions, and the substrate moves along the Z direction. The fault monitoring device includes a processor and a camera and a control component electrically connected to the processor. The camera is mounted on the control component. In a first state:

[0006] The control component is disposed in the 3D printing equipment and is used to move the camera so that the optical axis of the camera is parallel to the X direction, and its position in the Z direction is the same as the position of the nozzle of the nozzle in the Z direction, and the coordinate values ​​of the camera in the Y direction and the coordinate values ​​of the nozzle in the Y direction satisfy the following: ,in, B yi This indicates that the movement trajectory of the nozzle corresponding to each layer of the sheet is along the Y direction. i Each coordinate value B xi This indicates that the movement trajectory of the nozzle corresponding to each layer of the sheet is along the X-direction. i Each coordinate value C ys This represents the current coordinate value of the camera along the Y direction. fov This indicates the field of view of the camera in the Y direction. C xis a fixed value, and represents a coordinate value of the camera in the X direction; C is a constant, and takes a value of 2-5;

[0007] The camera is configured to collect a target region image in a preset collection mode, wherein the target region image includes a nozzle image and a printed model image below the nozzle.

[0008] The processor is configured to calculate a shortest distance between a pixel of the nozzle image and a pixel of the printed model image according to the target region image, and determine that the 3D printing device has a filament breakage fault if the shortest distance is greater than a preset threshold.

[0009] Preferably, a field of view of the camera satisfies:

[0010] ;

[0011] wherein, B x_min represents a minimum coordinate value of the nozzle along the X direction, C x represents a coordinate value of the camera in the X direction, L 1 represents a nearest distance from a nozzle of the nozzle head to the layer sheet; L 2 represents a height of the nozzle contained in the monitored region.

[0012] Further, the field of view of the camera is greater than 9°.

[0013] The two, a 3D printing system, comprising a 3D printing device and the aforementioned fault monitoring device, the 3D printing device comprising a nozzle head and a substrate, the nozzle head moving along the X and Y directions, and the substrate moving along the Z direction.

[0014] The three, a fault monitoring method, applied to a fault monitoring device, the fault monitoring device applied to a 3D printing device, the 3D printing device comprising a nozzle head and a substrate, the nozzle head moving along the X and Y directions, and the substrate moving along the Z direction, the fault monitoring device comprising a processor and a camera and a control component electrically connected to the processor, the camera being installed on the control component, in a first state, the control component being arranged in the 3D printing device, the method comprising:

[0015] The control component moves the camera, so that an optical axis of the camera is parallel to the X direction, and a position of the camera in the Z direction is the same as a position of a nozzle of the nozzle head in the Z direction, and so that a coordinate value of the camera in the Y direction satisfies:

[0016] ;

[0017] in, B yi This indicates that the movement trajectory of the nozzle corresponding to each layer of the sheet is along the Y direction. i Each coordinate value B xi This indicates that the movement trajectory of the nozzle corresponding to each layer of the sheet is along the X-direction. i Each coordinate value C ys This represents the current coordinate value of the camera along the Y direction. fov This indicates the field of view of the camera in the Y direction. C x This represents the coordinate value of the camera in the X direction, which is a fixed value; C It is a constant, with a value ranging from 2 to 5;

[0018] The camera acquires images of the target area according to a preset acquisition method, wherein the images of the target area include nozzle images and images of the printed model below the nozzle;

[0019] The processor calculates the shortest distance between the pixels of the nozzle image and the pixels of the printed model image based on the target area image, and determines that the 3D printing equipment has a filament breakage fault if the shortest distance is greater than a preset threshold.

[0020] The shooting field of view of the camera is also set to satisfy the following: ;

[0021] Among them, among them, B x_min This represents the minimum coordinate value that the nozzle can move to along the X direction. C x This represents the coordinate value of the camera in the X direction. L 1 indicates the closest distance between the nozzle of the spray head and the layer; L 2 represents the height of the nozzles contained within the monitored area.

[0022] Furthermore, the camera acquires images of the target area using one of the preset acquisition methods, including:

[0023] The camera acquires images of the target area according to a preset time period during the printing process of each layer of the printed model.

[0024] In addition, the camera can also acquire images of the target area according to a second preset acquisition method, including:

[0025] The camera is from the printed model. k’ Starting from the layer, every interval k The layer acquires images of the target area according to a preset time period, where...k’ It is an integer and greater than 1. k It is an integer and greater than 1.

[0026] Fourthly, a fault monitoring method for a 3D printing system, applied to a 3D printing system, the 3D printing system including a 3D printing device and a fault monitoring device, the 3D printing device including a nozzle and a substrate, the fault monitoring device including a processor and a camera and a control component electrically connected to the processor, the camera being mounted on the control component, and in a first state, the control component being disposed on the 3D printing device, the method comprising:

[0027] The nozzle moves along the X and Y directions, and the substrate moves along the Z direction to perform model printing;

[0028] The control component moves the camera so that its optical axis is parallel to the X direction, and its position in the Z direction is the same as the position of the nozzle in the Z direction, and the coordinates of the camera in the Y direction satisfy the following:

[0029] ;

[0030] in, B yi This indicates that the movement trajectory of the nozzle corresponding to each layer of the sheet is along the Y direction. i Each coordinate value B xi This indicates that the movement trajectory of the nozzle corresponding to each layer of the sheet is along the X-direction. i Each coordinate value C ys This represents the current coordinate value of the camera along the Y direction. fov This indicates the field of view of the camera in the Y direction. C x This represents the coordinate value of the camera in the X direction, which is a fixed value; C It is a constant, with a value ranging from 2 to 5;

[0031] The camera acquires images of the target area according to a preset acquisition method, wherein the images of the target area include nozzle images and images of the printed model below the nozzle;

[0032] The processor calculates the shortest distance between the pixels of the nozzle image and the pixels of the printed model image based on the target area image, and determines that the 3D printing equipment has a filament breakage fault if the shortest distance is greater than a preset threshold.

[0033] Similarly, the shooting field of view of the camera is set to satisfy: ;

[0034] wherein, B x_min represents the minimum coordinate value that the nozzle can move to along the X direction, C x represents the coordinate value of the camera in the X direction, L 1 represents the closest distance from the nozzle of the nozzle to the layer sheet; L 2 is the height of the nozzle contained in the monitored area.

[0035] The fault monitoring device, method and 3D printing system and the fault monitoring method thereof provided by the present application have at least the following beneficial effects:

[0036] The printing fault caused by the problem that the nozzle does not spit silk due to the nozzle blockage, material breakage and the like in the printing process of the 3D printing device can be monitored in real time and quickly. BRIEF DESCRIPTION OF DRAWINGS

[0037] figure 1 It is a structural schematic diagram of the 3D printing system of the present application.

[0038] figure 2 It is a schematic diagram of the fault monitoring method of the 3D printing system of the present application.

[0039] figure 3 It is a schematic diagram of the relationship between the camera position and the nozzle position in the first perspective of the present application.

[0040] figure 4 It is a schematic diagram of the relationship between the camera position and the nozzle position in the second perspective of the present application.

[0041] Among them, 10-nozzle, 20-substrate, 30-fault monitoring module, 301-camera, 302-regulation component. DETAILED DESCRIPTION

[0042] In order to make the purpose, technical scheme and advantages of the embodiments of the present application more clear, the technical scheme in the embodiments of the present application will be described clearly and completely below in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings herein can be arranged and designed in various different configurations.

[0043] Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the claimed present application, but only represents selected embodiments of the present application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present application without creative labor are within the scope of protection of the present application.

[0044] It should be noted that the embodiments and features in the present application can be combined with each other in the case of no conflict.

[0045] It should be noted that similar reference numerals and letters refer to like items in the following drawings, and thus, once an item is defined in one drawing, it is not necessary to further define and explain it in the subsequent drawings.

[0046] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship commonly understood by those skilled in the art, and are only for the convenience of describing the present application and simplifying the description, and thus cannot be understood as indicating or implying that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first", "second", and the like are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0047] In the description of the present application, it should also be noted that, unless otherwise explicitly specified and limited, the terms "arrangement", "installation", "connection", "connection" should be broadly understood, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0048] In one embodiment of the present application, reference can be made to figure 1 As shown in the figure, a fault monitoring device can be used to monitor the printing process of a 3D printing device. The 3D printing device in the embodiment includes at least a nozzle 10 and a substrate 20, wherein the nozzle 10 moves along the X and Y directions, and the substrate 20 moves along the Z direction. The fault monitoring device in the embodiment includes a processor and a camera 301 and a control assembly 302 electrically connected to the processor, and the camera 301 is installed on the control assembly 302. In a first state, i.e. when the fault monitoring device is applied to monitor the 3D printing device;

[0049] The camera 301 is used to collect target area images in a preset collection mode;

[0050] The aforementioned processor calculates the shortest distance between the pixels of the nozzle image and the pixels of the printed model image according to the target area images, and determines that the 3D printing device has a filament breakage fault in the case that the shortest distance is greater than a preset threshold.

[0051] And, in combination figure 4 As shown in the figure, the shooting field of view of the aforementioned camera 301 needs to meet:

[0052] ;

[0053] Wherein, B x_min represents the minimum coordinate value that the monitored nozzle 10 can move along the X direction, C x represents the coordinate value of the camera 301 in the X direction, L 1 represents the closest distance from the nozzle of the nozzle 10 to the layer sheet; L 2 is the height of the nozzle contained in the monitored area.

[0054] Based on the actual situation, for the commonly used 3D printing equipment on the market, the length of the substrate 20 along the X direction is generally-300~300mm, C x Generally set to-400mm, the layer spacing Δ d Take 0.3mm, take 20 layers, at this time That is, in this embodiment, the shooting field of view of the camera 301 fov >9° can meet the collection requirements.

[0055] Considering that only the center part of the raw image collected by the camera with a large shooting field of view contains the monitored area, on the one hand, it leads to the need for cutting processing of each frame of raw image collected, increasing the processing flow and time, on the other hand, it also wastes the resolution of the camera, therefore, preferably, the shooting field of view of the camera 301 is designed to be 10 degrees, which is conducive to obtaining higher spatial resolution image quality, and the coverage rate of the monitored area in the raw image is large, and subsequent cutting processing is not needed.

[0056] In another embodiment of the present application, a fault monitoring method based on the aforementioned fault monitoring device is involved, at this time, the aforementioned control assembly 302 is arranged on the aforementioned 3D printing equipment, and the aforementioned fault monitoring method comprises:

[0057] The camera 301 is moved by the control assembly 302, so that the optical axis of the camera 301 is parallel or approximately parallel to the X direction, while keeping the position of the camera 301 in the Z direction the same as the position of the nozzle of the nozzle 10 in the Z direction, and making the coordinate value of the camera 301 in the Y direction satisfy: Wherein, B yi represents the first i directional coordinate value of the motion track of the nozzle corresponding to one layer of layer sheet along the Y direction,Each coordinate value B xi This indicates that the movement trajectory of the nozzle corresponding to each layer of the sheet is along the X-direction. i Each coordinate value C ys This indicates the current coordinate value of the camera 301 along the Y direction. fov This indicates the field of view of the camera 301 in the Y direction. C x This represents the coordinate value of the camera 301 in the X direction, which is a fixed value; C It is a constant, with a value ranging from 2 to 5;

[0058] In this embodiment, the camera 301 acquires images of the target area according to a preset time period during the printing process of each layer of the printing model, or the camera 301 acquires images of the target area from the printing model at the next specified time period. k’ Starting from the layer, every interval k The layer acquires images of the target area according to a preset time period, where... k’ It is an integer and greater than 1. k It is an integer greater than 1. Meanwhile, the aforementioned target area image includes the nozzle image and the printed model image below the nozzle.

[0059] Based on the two preset acquisition methods for acquiring target area images of the aforementioned camera 301, the aforementioned L The closest distance between the nozzle and the layer, as indicated by 1, can be determined in two different ways.

[0060] Firstly, if the camera 301 is configured to acquire images of each layer of film and a nozzle failure occurs, then... L The value of 1 is approximately one interlayer spacing Δ d Interlayer spacing Δ d The thickness is typically 0.1~0.3mm;

[0061] Secondly, if the acquisition method of camera 301 is set to start from the first... k’ Starting from the layer, every interval k When the camera 301 is acquiring images from the layered film and a nozzle malfunctions by not spouting silk, the maximum value of L1 is: k The distance between each layer, i.e. k* Δ d .

[0062] When using the aforementioned processor to determine if a filament breakage fault has occurred in a 3D printing device, a threshold can be set according to actual needs. For example, the threshold can be determined based on the distance between the nozzle pixels and the layer pixels during normal printing. Another example is when acquiring images of the monitored area for each layer, the threshold can be equal to or less than Δ. d Δd This is a layer spacing distance (layer thickness). If the aforementioned minimum distance exceeds the threshold, it indicates that printhead 10 is not spouting filament, and a printing error has occurred.

[0063] In another embodiment, the aforementioned fault monitoring method is applied to a 3D printing system, which relates to a fault monitoring method for a 3D printing system.

[0064] Specifically, the aforementioned 3D printing system includes the aforementioned 3D printing equipment and the aforementioned fault monitoring equipment.

[0065] In this embodiment, the 3D printing equipment includes a nozzle 10, a substrate 20, a fault monitoring module 30, a filament feed module (not shown in the figure), and the aforementioned processor (not shown in the figure). The fault monitoring module 30 includes a control component 302 and a camera 301. The control component 302 can control the camera 301 to translate along the Y direction. The fault monitoring module 30 and the processor are communicatively connected. The processor can control the translation of the nozzle 10 in the X and Y directions and the translation of the substrate 20 in the Z direction, and control the fault monitoring module 30 to perform fault monitoring.

[0066] When printing a model using a 3D printing device, the paths for each layer are obtained based on the slicing file of the 3D model. The movement paths of the nozzle 10 in the X and Y directions and the interlayer spacing between layers are determined. Under processor control, the substrate 20 moves along the Z direction, and the nozzle 10 moves according to its path in the X / Y plane, extruding filament from the nozzle. The hot-melt material adheres to the substrate or the previously cured layer. After each layer is printed, the substrate 20 is moved down one interlayer spacing along the Z direction. This process is repeated layer by layer until all layers are deposited, forming the final model. During the printing process of this 3D printing device, the position of the nozzle 10 in the Z direction is fixed.

[0067] The fault monitoring module 30 is disposed on one side of the substrate 20. The control component 302 is specifically an electric displacement stage used to adjust and control the coordinate position of the camera 301 along the Y direction. The camera 301 is specifically a camera module, preferably a self-focusing camera module, but it can also be a non-focusing camera module. When the nozzle 10 moves along the X direction, the camera 301 automatically focuses to ensure that the image of the nozzle 10 captured by the camera 301 is clear. The coordinates of the center position of the imaging focal plane of the camera 301 are set as the camera coordinates. The optical axis of the camera 301 is parallel or approximately parallel to the X-axis. After the fault monitoring module 30 is fixedly assembled, the center of the focal plane of the camera 301 is used as the origin. The position values ​​of the camera 301 in the X and Z directions are fixed values, while the coordinate value in the Y direction changes with the control of the control component 302. The position coordinates of the nozzle 10 are represented by the center coordinates of the nozzle on the nozzle 10. The position of the nozzle 10 in the Z direction is a fixed value. The position of the camera 301 in the Z direction is consistent with the position of the nozzle 10 in the Z direction. That is, the coordinate value of the focal plane center of the camera 301 in the Z direction is the same as the coordinate value of the nozzle 10 in the Z direction.

[0068] In this embodiment, you can refer to figure 2 As shown, the aforementioned 3D printing system fault monitoring method includes:

[0069] Step S1: Obtain model printing information;

[0070] Specifically, when the 3D printing equipment starts the printing task of the 3D model, the processor obtains the model printing information based on the 3D model's slice file. This information includes the interlayer spacing, the total number of layers, the motion trajectory of the nozzle 10 corresponding to each layer, and the printing start time for each layer. The motion trajectory of the nozzle 10 corresponding to each layer refers to the coordinates of the nozzle 10 during the printing process. B x , B y The trajectory of change in chronological order.

[0071] Step S2: Set the motion mode of the control components and the acquisition mode of the camera;

[0072] In this embodiment, the acquisition method of camera 301 can be:

[0073] Camera 301 is configured to acquire images of each layer of film. Specifically, during the printing process of each layer, camera 301 acquires images at intervals of time T. The time interval T refers to the time at which the camera acquires an image every T time intervals, starting from the start time of printing each layer.

[0074] In this embodiment, the acquisition method of camera 301 can also be:

[0075] Set camera 301 from the... k’ Starting from the layer, every interval k Layer by layer, camera 301 acquires images. Specifically, when the first... k’ Starting from the first layer, for the first... k’ In the first layer, camera 301 acquires images according to a time period T; for the first layer... k'+k+1 In the first layer, camera 301 acquires images according to a time period T; for the first layer... k'+2k+1 Layer by layer, camera 301 acquires images according to a time period T;... Since camera 301 does not need to acquire images during each layer printing process, but rather during each printing... k After layer-by-layer imaging, camera 301 acquires images. This reduces the power consumption of camera 301. Furthermore, if the nozzle fails to sputter, the very small interlayer spacing (typically 0.1mm) makes it difficult to identify 0.1mm tomographic features from the acquired images. k As the printing time of each layer increases, this discontinuity will increase. k This increases the accuracy and ease of identifying tomographic features in the acquired images. k The value of is an integer greater than 1. k Taking a value between 5 and 20 is beneficial for the calculation of fault characteristics in the subsequent step S4, and the waste of material is negligible when a printing error is detected.

[0076] The motion mode of the control component 302 refers to the trajectory of the camera 301 along the Y direction controlled by the control component 302, that is, the way the coordinates of the camera 301 in the Y direction change over time.

[0077] In this embodiment, the aforementioned control component 302 can move in the following manner:

[0078] The Y-coordinates of the control camera 301 and the printhead 10 are kept synchronized. That is, the processor extracts all B values ​​corresponding to the nozzles on the current layer to be printed, based on the movement trajectory of the printhead. yi The values ​​are arranged in ascending order of time to obtain a set of motion vectors, [( t 1 , B y1 ),( t 2 , B y2 ), ..., ( t i , B yi ),…,( t n, B yn )],in, t i Indicates the first i indivual B yi The value corresponds to the printing time. B yi Representative at the t i The nozzle of spray head 10 is in the Y direction at the time. i Each coordinate value. Under the control of the processor, the control component 302 controls the camera 301 to move along the Y direction according to the aforementioned motion vector and... t i Coordinates corresponding to time C yi The value is equal to B yi .

[0079] In this embodiment, the aforementioned control component 302 can also move in the following manner:

[0080] Under the control of the processor, the control component 302 controls the camera 301 to move intermittently. That is, when the coordinate values ​​of the camera 301 and the nozzle of the nozzle 10 in the Y direction satisfy the following relationship (1), the control component 302 does not move in the Y direction; when the following relationship (1) is not satisfied, the control component 302 controls the camera 301 to move along the Y direction to the coordinate position of the nozzle.

[0081] (1);

[0082] in, B yi This indicates that the nozzle movement trajectory of the nozzle 10 corresponding to each layer of the sheet is along the Y direction. i Each coordinate value B xi This indicates that the aforementioned nozzle movement trajectory corresponding to each layer of the sheet is along the X-direction. i Each coordinate value C ys This indicates the current coordinate value of the camera 301 along the Y direction. fov This indicates the field of view of the camera 301 in the Y direction. C x This represents the coordinate value of the camera 301 in the X direction, which is a fixed value; C It is a constant, which can be 2 or greater than 2, preferably 2 to 5.

[0083] Specifically, such as figure 3As shown in the figure, point P represents a certain printing time point in the printing process of layer by layer. The nozzle of printhead 10 is at position P, and the coordinates of position P are ( B xi , B yi The coordinates of camera 301 at position C are ( C x , C ys The field of view of camera 301 along the Y direction is fov. When these two sets of coordinates satisfy the above formula (1), it means that the nozzle of nozzle 10 is within the shooting range of camera 301, that is, camera 301 can collect an effective target image; when the above two sets of coordinates do not satisfy the above formula (1), camera 301 is controlled to move along the Y direction, thereby controlling camera 301 to move along the Y direction.

[0084] Furthermore, as the layers begin to print, the coordinates of the current camera 301 are calculated. C ys and the first coordinate point B y1 If the difference satisfies equation (1), it means that the nozzle of the nozzle 10 is within the camera's shooting range, i.e., the camera 301 can acquire the target image, and the control component 302 does not move in the Y direction. If it does not satisfy the equation, the control component 302 controls the camera 301 to move along the Y direction to the coordinates. B y1 The position, where the coordinates of the current camera in the relation are... C ys The value is equal to B y1 The value is then calculated for the next coordinate.

[0085] In this embodiment, comparing the two movement modes of the aforementioned control component 302, controlling the camera 301 to move intermittently using the control component 302 is less efficient than keeping the coordinates of the camera 301 in the Y direction and the nozzle 10 in the Y direction synchronized. This may save more power and extend the service life of the control component 302.

[0086] In this embodiment, the acquisition mode of camera 301 and the movement mode of control component 302 can be arbitrarily combined. For example, in one embodiment, the acquisition mode of camera 301 is set to start from the first... k’ Starting from the layer, every interval k The camera 301 acquires images layer by layer, and the movement of the control component 302 is to control the coordinate values ​​of the camera 301 in the Y direction and the nozzle of the nozzle 10 in the Y direction. B yThe values ​​remain synchronized; in this combination, when performing the first... k’ , k'+k+1 , k'+2k+1 When printing layer by layer, the control component 302 controls the coordinate position of the camera 301 along the Y direction. When printing other layers, the control component 302 does not control the movement of the camera 301 in the Y direction.

[0087] Step S3: Acquire images of the monitored area; interval k Layer acquisition begins;

[0088] During the printing process of each layer of film, camera 301 acquires images according to a time period T (after sampling begins, an image is acquired every T during the acquisition process of that layer; the acquisition period for the layer for which an image needs to be acquired is T, which is a fixed value obtained by dividing the average printing time per layer by the number of films; for example, if it is determined that 20 films will be acquired, the average printing time per layer / 20 = T). The time period T is a preset value and can be set according to actual needs. For example, if the time period T is 2s, then camera 301 will acquire an image every 2s.

[0089] The monitored area includes the nozzle of printhead 10 and several printed layers near the nozzle.

[0090] Since the shooting optical axis of camera 301 is parallel or approximately parallel to the X direction, the coordinates of camera 301 in the Z direction are consistent with the coordinates of nozzle 10 in the Z direction. Combined with the setting of the movement mode of control component 302 in step S2, the monitored area can always be covered by the central field of view of camera 301.

[0091] refer to figure 4 The field of view of camera 301 fov The aforementioned relation is satisfied, namely: At all times, the camera is able to capture images of the monitored area.

[0092] in, B x_min This represents the minimum coordinate value that the nozzle of nozzle 10 can move to along the X direction. C x This represents the coordinate value of the camera 301 in the X direction. L 1 indicates the closest distance between the nozzle of the nozzle 10 and the sheet. If the acquisition method of the camera 301 is set to acquire images of each sheet and a fault occurs where the nozzle 10 does not spout silk, L The value of 1 is approximately one interlayer spacing Δ d Interlayer spacing Δ d The typical range is 0.1~0.3mm; if the acquisition method of camera 301 is set to start from the first...k’ Starting from the layer, every interval k When the camera 301 is acquiring images from the layered film, and a fault occurs where the nozzle 10 fails to spout silk, L The maximum value of 1 is k The distance between each layer, k* Δ d ; L 2 represents the height of the nozzles within the monitored area, typically set to 2mm.

[0093] By following steps S1 to S3, it can be ensured that the camera can obtain images of the monitored area.

[0094] Step S4: Calculate the fault features of the monitored area image to obtain fault feature values;

[0095] When a certain layer (such as the first one mentioned above) k’ Layer, or first k'+k+1 , or the k'+2k+1 After the layer is printed, camera 301 acquires multiple images (e.g., the 20 images mentioned earlier) of the monitored area during the layer printing process. The multiple raw images acquired by camera 301 are first subjected to conventional image processing operations, such as grayscale processing, noise reduction, and filtering, to obtain the first image. Then, a feature recognition algorithm is used to obtain the pixel coordinate set of the nozzle image and the pixel coordinate set of the printed layer image in the first image. The pixel coordinate set of the nozzle in the first image refers to the set of coordinates of all pixels (including the pixels of the filaments inside the nozzle) constituting the nozzle image in the first image, denoted as the nozzle pixel coordinate set. The pixel coordinate set of the printed layer in the first image refers to the set of coordinates of all pixels (including the filaments inside the nozzle) constituting the printed layer image in the first image, denoted as the layer pixel coordinate set. The process involves calculating the closest pixel pairs between the nozzle pixel coordinate set and the layer pixel coordinate set. Specifically, multiple images of the monitored area are processed as follows: The coordinates of a pixel in the nozzle pixel coordinate set are compared with the coordinates of every pixel in the layer pixel coordinate set using Euclidean distance calculations. This yields a series of Euclidean distances. This process is repeated for all pixels in the nozzle pixel coordinate set, obtaining the Euclidean distance between each pixel coordinate in the nozzle pixel coordinate set and each pixel coordinate in the layer pixel coordinate set. The minimum value among these Euclidean distances is used as a feature value for that image. Finally, multiple feature values ​​are obtained for multiple images. These feature values ​​undergo routine data processing, such as outlier removal. The average value of the processed feature values ​​is then calculated and used as the fault feature value.

[0096] Step S5: Determine whether a printing error has occurred based on the fault characteristic value. If a printing error is determined to have occurred, proceed to step S6; otherwise, return to step S3.

[0097] In this embodiment, the threshold value for the fault characteristic value of a printing failure is preset and can be set according to actual needs. For example, the threshold can be determined based on the distance between the nozzle pixel and the layer pixel during normal printing. Another example is that when acquiring an image of the monitored area for each layer, the threshold can be equal to or less than Δ. d Δ d This refers to the interlayer spacing (layer thickness) mentioned earlier.

[0098] The fault characteristic value obtained in step S4 is compared with the threshold. If it exceeds the threshold, it means that the printhead is not spouting filament, and a printing error is determined to have occurred. Then, proceed to step S6.

[0099] If the fault characteristic value is within the threshold range, it indicates that the printhead is spitting out filament, and it is determined that no printing error has occurred. Then, return to step S3.

[0100] Step S6: Issue a printing error alarm and stop the printing job.

[0101] In this embodiment, if a printing error is confirmed, a printing error alarm is issued. The printing error alarm can be displayed in text form on the control panel or warned in sound form.

[0102] The 3D printing fault monitoring method provided by this invention can monitor printing faults that may occur in 3D printing equipment during the printing process, such as nozzle blockage or material breakage, which may cause the nozzle to not spout filament.

[0103] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A fault monitoring device, characterized in that, Applied to a 3D printing device, the 3D printing device includes a nozzle and a substrate, the nozzle moves along the X and Y directions, and the substrate moves along the Z direction. The fault monitoring device includes a processor and a camera and a control assembly electrically connected to the processor. The camera is mounted on the control assembly. In a first state: The control component is disposed in the 3D printing equipment and is used to move the camera so that the optical axis of the camera is parallel to the X direction, and its position in the Z direction is the same as the position of the nozzle of the nozzle in the Z direction, and the coordinate values ​​of the camera in the Y direction and the coordinate values ​​of the nozzle in the Y direction satisfy the following relationship: ,in, B yi This indicates that the movement trajectory of the nozzle corresponding to each layer of the sheet is along the Y direction. i Each coordinate value B xi This indicates that the movement trajectory of the nozzle corresponding to each layer of the sheet is along the X-direction. i Each coordinate value C ys This represents the current coordinate value of the camera along the Y direction. fov This indicates the field of view of the camera in the Y direction. C x This represents the coordinate value of the camera in the X direction, which is a fixed value; C It is a constant, with a value ranging from 2 to 5; Under the control of the processor, the control component controls the camera to move intermittently. That is, when the coordinate values ​​of the camera and the nozzle of the spray head in the Y direction satisfy the above relationship, the control component does not move in the Y direction; when the above relationship is not satisfied, the control component controls the camera to move along the Y direction to the coordinate position of the nozzle. The camera is used to acquire images of a target area according to a preset acquisition method, wherein the target area image includes a nozzle image and an image of the printed model below the nozzle; The processor is configured to calculate the shortest distance between the pixels of the nozzle image and the pixels of the printed model image based on the target area image, and determine that the 3D printing equipment has a filament breakage fault if the shortest distance is greater than a preset threshold.

2. The fault monitoring device according to claim 1, characterized in that, The camera's field of view satisfies: ； in, B x_min This represents the minimum coordinate value that the nozzle can move to along the X direction. C x This represents the coordinate value of the camera in the X direction. L 1 indicates the closest distance between the nozzle of the spray head and the layer; L 2 represents the height of the nozzles contained within the monitored area.

3. The fault monitoring device according to claim 1, characterized in that, The camera has a field of view greater than 9°.

4. A 3D printing system, characterized in that, The invention includes a 3D printing device and a fault monitoring device as described in any one of claims 1 to 3, wherein the 3D printing device includes a nozzle and a substrate, the nozzle moving along the X and Y directions, and the substrate moving along the Z direction.

5. A fault monitoring method, characterized in that, A fault monitoring device is applied to a 3D printing device, the 3D printing device including a nozzle and a substrate, the nozzle moving along the X and Y directions, the substrate moving along the Z direction, the fault monitoring device including a processor and a camera and a control component electrically connected to the processor, the camera being mounted on the control component, and in a first state, the control component being disposed in the 3D printing device, the fault monitoring method including: The control component moves the camera so that its optical axis is parallel to the X-direction, and its position in the Z-direction is the same as the position of the nozzle in the Z-direction, and the coordinates of the camera in the Y-direction and the coordinates of the nozzle in the Y-direction satisfy the following relationship: ； in, B yi This indicates that the movement trajectory of the nozzle corresponding to each layer of the sheet is along the Y direction. i Each coordinate value B xi This indicates that the movement trajectory of the nozzle corresponding to each layer of the sheet is along the X-direction. i Each coordinate value C ys This represents the current coordinate value of the camera along the Y direction. fov This indicates the field of view of the camera in the Y direction. C x This represents the coordinate value of the camera in the X direction, which is a fixed value; C It is a constant, with a value ranging from 2 to 5; Under the control of the processor, the control component controls the camera to move intermittently. That is, when the coordinate values ​​of the camera and the nozzle of the spray head in the Y direction satisfy the above relationship, the control component does not move in the Y direction; when the above relationship is not satisfied, the control component controls the camera to move along the Y direction to the coordinate position of the nozzle. The camera acquires images of the target area according to a preset acquisition method, wherein the images of the target area include nozzle images and images of the printed model below the nozzle; The processor calculates the shortest distance between the pixels of the nozzle image and the pixels of the printed model image based on the target area image, and determines that the 3D printing equipment has a filament breakage fault if the shortest distance is greater than a preset threshold.

6. The method according to claim 5, characterized in that, Also includes: The shooting field of view of the camera is set to satisfy: ; in, B x_min This represents the minimum coordinate value that the nozzle can move to along the X direction. C x This represents the coordinate value of the camera in the X direction. L 1 indicates the closest distance between the nozzle of the spray head and the layer; L 2 represents the height of the nozzles contained within the monitored area.

7. The method according to claim 5 or 6, characterized in that, The camera acquires images of the target area according to a preset acquisition method, including: The camera acquires images of the target area according to a preset time period during the printing process of each layer of the printed model.

8. The method according to claim 5 or 6, characterized in that, The camera acquires images of the target area according to a preset acquisition method, including: The camera is from the printed model. k 'Starting from the layer, every interval' k The layer acquires images of the target area according to a preset time period, where... k ' is an integer greater than 1, k It is an integer and greater than 1.

9. A method for fault monitoring in a 3D printing system, characterized in that, An application in a 3D printing system, the 3D printing system including a 3D printing device and a fault monitoring device, the 3D printing device including a nozzle and a substrate, the fault monitoring device including a processor and a camera and a control component electrically connected to the processor, the camera being mounted on the control component, and in a first state, the control component being disposed on the 3D printing device, the 3D printing system fault monitoring method including: The nozzle moves along the X and Y directions, and the substrate moves along the Z direction to perform model printing; The control component moves the camera so that its optical axis is parallel to the X-direction, and its position in the Z-direction is the same as the position of the nozzle in the Z-direction, and the coordinates of the camera in the Y-direction and the coordinates of the nozzle in the Y-direction satisfy the following relationship: ； in, B yi This indicates that the movement trajectory of the nozzle corresponding to each layer of the sheet is along the Y direction. i Each coordinate value B xi This indicates that the movement trajectory of the nozzle corresponding to each layer of the sheet is along the X-direction. i Each coordinate value C ys This represents the current coordinate value of the camera along the Y direction. fov This indicates the field of view of the camera in the Y direction. C x This represents the coordinate value of the camera in the X direction, which is a fixed value; C It is a constant, with a value ranging from 2 to 5; Under the control of the processor, the control component controls the camera to move intermittently. That is, when the coordinate values ​​of the camera and the nozzle of the spray head in the Y direction satisfy the above relationship, the control component does not move in the Y direction; when the above relationship is not satisfied, the control component controls the camera to move along the Y direction to the coordinate position of the nozzle. The camera acquires images of the target area according to a preset acquisition method, wherein the images of the target area include nozzle images and images of the printed model below the nozzle; The processor calculates the shortest distance between the pixels of the nozzle image and the pixels of the printed model image based on the target area image, and determines that the 3D printing equipment has a filament breakage fault if the shortest distance is greater than a preset threshold.

10. The 3D printing system fault monitoring method according to claim 9, characterized in that, Also includes: The shooting field of view of the camera is set to satisfy: ; in, B x_min This represents the minimum coordinate value that the nozzle can move to along the X direction. C x This represents the coordinate value of the camera in the X direction. L 1 indicates the closest distance between the nozzle of the spray head and the layer; L 2 represents the height of the nozzles contained within the monitored area.

Images