A method and system for optimizing the control accuracy of a 3D printer based on feedback control

Abstract

The present invention relates to the technical field of data processing, and discloses a method and system for optimizing the control precision of a 3D printer based on feedback control. The method collects existing three-dimensional model data through an installed laser device or scans and stores the three-dimensional model data of an existing object in real time, constructs a sample set based on the collected or real-time scanned three-dimensional model data, and at the same time completes the processing of the three-dimensional model data by numbering, slicing and determining the contour of each layer of slice of the collected three-dimensional model data, and transmits the processed three-dimensional model data to the 3D printer. The printing process of the 3D printer is monitored through an installed Internet of Things monitoring device, and at the same time the real-time monitored data is analyzed, and the 3D printer is accurately controlled according to the analysis result, thereby improving the control precision of the 3D printer.

Description

Technical Field

[0001] The present invention relates to the technical field of data processing, and specifically provides an optimization method and system for the control precision of a 3D printer based on feedback control. Background Art

[0002] With the continuous development of technology and manufacturing, 3D printing technology has become an important technology in the modern manufacturing field. However, due to the diversification of 3D printing materials, there are still many challenges in the current multi-color 3D printing technology, such as low printing efficiency, low precision, and single color of the formed parts.

[0003] Existing technologies such as Chinese Patent Application CN116880788A use a sensing signal acquisition unit to collect local sensing signals of the printer and send them to an online server, a driving signal acquisition unit to collect local driving signals of the printer and send them to the online server, and a status signal acquisition unit to collect local status signals of the printer and send them to the online server. The online server calculates a network resource consumption signal value based on the local sensing signals, local driving signals, and local status signals of the printer, and accurately judges the working state of the 3D printer through the network resource consumption signal value, and then appropriately allocates network resources. However, it fails to solve the problems of 3D printing technology in terms of printing efficiency and precision, and has certain limitations. Summary of the Invention

[0004] (I) Technical Problems to be Solved

[0005] Aiming at the deficiencies of the existing technology, the present invention provides an optimization method and system for the control precision of a 3D printer based on feedback control, which has the advantages of high precision and real-time control, and solves the problem of low printing precision in 3D printing technology.

[0006] (II) Technical Solutions

[0007] To solve the above technical problems of low printing precision in 3D printing technology, the present invention provides the following technical solutions:

[0008] The present invention discloses an optimization method for the control precision of a 3D printer based on feedback control, which specifically includes the following steps:

[0009] S1. Install a three-dimensional laser scanning device, collect existing three-dimensional model data through the installed laser device or real-time scan and store the three-dimensional model data of an existing object, and construct a sample set based on the collected or real-time scanned three-dimensional model data;

[0010] S2. Process the three-dimensional model data in the constructed sample set to obtain processed three-dimensional model data, and input the obtained processed three-dimensional model data into the 3D printer;

[0011] S3. Based on the processed 3D model data obtained, print it using a 3D printer, and install an Internet of Things monitoring device inside the 3D printer to collect various parameters of the 3D printer in real time through the installed Internet of Things monitoring device;

[0012] S4. Based on the various parameters of the 3D printer collected in real time, analyze the various parameters of the 3D printer collected in real time through a data analysis algorithm to obtain the analyzed various parameters of the 3D printer;

[0013] S5. Perform real-time control based on the obtained analyzed various parameters of the 3D printer.

[0014] In the present invention, existing 3D model data is collected through the installed laser device or the 3D model data of an existing object is scanned in real time and stored, and a sample set is constructed based on the collected or real-time scanned 3D model data. At the same time, the 3D model data is processed by numbering, slicing, and determining the contour of each layer of the slice, and the processed 3D model data is transmitted to the 3D printer. The printing process of the 3D printer is monitored through the installed Internet of Things monitoring device, and the real-time monitored data is analyzed at the same time. According to the analysis results, the 3D printer is precisely controlled, improving the control accuracy of the 3D printer.

[0015] Preferably, constructing a sample set based on the collected or real-time scanned 3D model data includes the following steps:

[0016] Set the format of collecting existing 3D model data and real-time scanning and storing the 3D model data of an existing object as an STL format file;

[0017] The structure of the STL format file is composed of n triangular patches.

[0018] Preferably, processing the 3D model data in the constructed sample set includes the following steps:

[0019] S21. Obtain the topological information of all triangular patches in the STL format file, and number them based on the obtained topological information;

[0020] S22. Based on the numbered 3D model obtained, slice it by setting a height and determine the contour of the cutting plane;

[0021] S23. Collect the determined contour of the cutting plane, arrange them in reverse order according to the height of the cutting plane, and output the information on the number of layers of the cutting plane generated after slicing;

[0022] Set the information on the number of layers of the cutting plane generated after slicing output as the processed 3D model data, and input the processed 3D model data into the 3D printer.

[0023] Preferably, obtaining the topological information of all triangular facets in the STL format file and numbering based on the obtained topological information includes the following steps:

[0024] Read the number n of triangular facets in the STL format file, select a vertex on the contour of the 3D model data as the initial point, and based on the selected initial point, sequentially traverse the vertex coordinates of each triangular facet;

[0025] Set up a linked list for numbering, and set the triangular facet where the initial point is located as the first number in the linked list;

[0026] When it is detected during the traversal that the two coordinates of two triangular facets are the same, set the two triangular facets with the same two coordinates as adjacent facets;

[0027] Based on the traversal order, insert the number of the later traversed triangular facet after the number of the adjacent facet and update the number until all triangular facets are traversed.

[0028] Preferably, based on the obtained numbered 3D model, slicing is performed by setting a height and determining the contour of the cutting plane includes the following steps:

[0029] Set the slicing thickness, and slice it evenly from the bottom of the 3D model upwards with a horizontal cutting plane perpendicular to the Z axis according to the set thickness;

[0030] After slicing is completed, connect the intersecting line segments formed by all triangular facets and the cutting plane to determine the contour of the cutting plane, and calculate all the contours of the cutting plane;

[0031] The calculation formula for the contour of the cutting plane is as follows:

[0032] Set the height of cutting plane 1 as h, and the three vertex coordinates of triangular facet ABC are respectively: A(x 1 , y 1 , z 1 ), B(x 2 , y 2 , z 2 ), C(x 3 , y 3 , z 3 ), and the intersection coordinates D 1 , D 2 The calculation formula is as follows:

[0033]

[0034] Among them, x represents the abscissa, y represents the ordinate, z represents the vertical coordinate, and h represents the height of the cutting plane.

[0035] The present invention obtains the topological information of all triangular facets in an STL format file, numbers them based on the obtained topological information, slices the three-dimensional model after numbering by setting a height, determines the contour of the cutting plane. At the same time, collects the determined contour of the cutting plane, arranges them in reverse order according to the cutting plane height, outputs the information on the number of cutting planes generated after slicing, and transmits the output data to a 3D printer, improving the accuracy of the data of the 3D printer.

[0036] Preferably, the various parameters of the 3D printer are collected in real time by the installed Internet of Things monitoring device, including:

[0037] The installed Internet of Things monitoring device includes: a printing image comparison device, a material flow detection device, and a temperature detection device

[0038] The various parameters of the 3D printer include: material flow and temperature.

[0039] Preferably, based on the various parameters of the 3D printer collected in real time, the analysis of the various parameters of the 3D printer collected in real time by a data analysis algorithm includes the following steps:

[0040] S41. Comparison of material flow detection;

[0041] Set the minimum threshold and the maximum threshold of the material flow during 3D printing;

[0042] Compare based on the set threshold and the material flow value detected in real time by the material flow detection device to determine whether the material flow is normal during 3D printing;

[0043] S42. Comparison of 3D printer temperature detection;

[0044] Set the maximum threshold of the 3D printer temperature during 3D printing;

[0045] Compare based on the set threshold and the 3D printer temperature value detected in real time by the temperature detection device to determine whether the 3D printer temperature is normal during 3D printing;

[0046] S43. Comparison of model contour detection.

[0047] Preferably, the model contour detection comparison includes the following steps:

[0048] S431. Extract the contour image of the projection of the three-dimensional model printed in 3D on the projection plane;

[0049] S432. Extract the contour of the cutting plane from the processed three-dimensional data;

[0050] S433. Match the sectional plane contour in the processed three-dimensional data with the projected contour image of the 3D printed three-dimensional model on a plane;

[0051] S434. Determine the matching degree between the 3D printed three-dimensional model and the sectional plane contour in the processed three-dimensional data according to the coincidence degree of the contour lines;

[0052] Let M(Θ) represent the 3D printed three-dimensional model, the projected image of the 3D printed three-dimensional model on the two-dimensional plane be m(M(Θ)), and the sectional plane contour image in the processed three-dimensional data be P m(M(Θ)) ; For the input three-dimensional model D, the contour image obtained through contour extraction is P D ; Use the similarity function S(Θ) to judge the contour images P m(M(Θ)) and P D for their coincidence degree;

[0053]

[0054] where Q 0 (Θ) is the area of the overlapping part of the two contours P m(M(Θ)) and P D , Q(C m(M(Θ)) ) and Q(P D ) are the areas of the corresponding contours respectively; 0 ≤ S ≤ 1, the larger S is, the more similar the two regions are, and when the two regions overlap, S = 1;

[0055] Set the threshold for the matching degree between the 3D printed three-dimensional model and the sectional plane contour in the processed three-dimensional data.

[0056] The present invention realizes the monitoring of the 3D printing process by comparing the material flow rate detection, the 3D printer temperature detection, and the coincidence degree of the comparison contour lines to judge the matching degree between the 3D printed three-dimensional model and the sectional plane contour in the processed three-dimensional data, ensuring the accuracy of the 3D printing process.

[0057] Preferably, the real-time control based on the obtained analyzed parameters of the 3D printer includes the following steps:

[0058] S51. Perform real-time control on the 3D printer based on the material flow rate detection comparison;

[0059] When the material flow rate value detected by the material flow rate detection device in real time is less than or equal to the set minimum material flow rate threshold, stop printing and check whether there is a blockage in the material delivery pipe of the 3D printer;

[0060] When the material flow rate value detected by the material flow rate detection device in real time is greater than or equal to the set maximum material flow rate threshold, reduce the material flow rate by adjusting the pressure of the material delivery pipe of the 3D printer;

[0061] S52. Perform real-time control of the 3D printer based on the comparison of the temperature detection of the 3D printer;

[0062] When the temperature value of the 3D printer detected in real time by the temperature detection device is greater than or equal to the maximum threshold of the set 3D printer temperature, stop printing;

[0063] S53. Perform real-time control of the 3D printer based on the comparison of the model contour detection;

[0064] When the cross-sectional plane contour in the 3D printed three-dimensional model does not coincide with the processed three-dimensional data, continuously adjust the 3D printed three-dimensional model according to the degree of similarity until the contour image areas coincide;

[0065] Continuously adjusting the 3D printed three-dimensional model according to the degree of similarity includes the following steps:

[0066] Continuously adjust the 3D printed three-dimensional model by the linear interpolation method;

[0067] Set the current printing point coordinates of the 3D printed three-dimensional model as w(x w , y w ), the next printing point coordinates as e(x e , y e ), and the deviation function F w of the printing point is expressed as follows:

[0068] F w = y w x e - x w y e

[0069] When the calculated deviation function F w of the printing point is 0, it means that the current printing point is printed correctly. When the calculated deviation function F w of the printing point is > 0, it means that the current printing point is printed too high, and then adjust it in the positive x-axis direction. When the calculated deviation function F w of the printing point is < 0, it means that the current printing point is printed too low, and then adjust it in the positive y-axis direction.

[0070] The present invention continuously adjusts the 3D printed three-dimensional model by the linear interpolation method, establishes the deviation function between the current printing point and the next printing point, and continuously adjusts the 3D printed three-dimensional model based on the calculation result of the deviation function, improving the control accuracy of the 3D printer.

[0071] The present invention also discloses a 3D printer control precision optimization system based on feedback control, including a material feeding pipe, a material flow detection device, a printing image comparison device, a temperature detection device, a three-dimensional laser scanning device, a model slicing module, a contour determination module, and a printer analysis and control module;

[0072] The three-dimensional laser scanning device is used to collect existing three-dimensional model data in real time or scan and store the three-dimensional model data of existing objects in real time;

[0073] The model slicing module is used to slice the collected three-dimensional model data at a set height;

[0074] The contour determination module is used to determine the sectional plane contour data of each layer of the three-dimensional model after slicing;

[0075] The material feeding pipe is used to convey materials into the 3D printer;

[0076] The material flow detection device is used to monitor the material conveying flow rate of the material feeding pipe in real time;

[0077] The temperature detection device is used to monitor the temperature change of the 3D printer in real time;

[0078] The printing image comparison device is used to compare the sectional plane contour in the three-dimensional data with the projected contour image of the 3D printed three-dimensional model on a plane;

[0079] The printer analysis and control module is used to control the 3D printer according to the analysis and comparison results.

[0080] (III) Beneficial effects

[0081] Compared with the prior art, the present invention provides a 3D printer control precision optimization method and system based on feedback control, having the following beneficial effects:

[0082] 1. The invention collects existing three-dimensional model data through the installed laser device or scans and stores the three-dimensional model data of existing objects in real time, constructs a sample set based on the collected or real-time scanned three-dimensional model data, and at the same time completes the processing of the three-dimensional model data by numbering, slicing, and determining the contour of each layer of the sliced data, and transmits the processed three-dimensional model data to the 3D printer. The printing process of the 3D printer is monitored through the installed Internet of Things monitoring device, and the real-time monitored data is analyzed at the same time. The 3D printer is accurately controlled according to the analysis results, improving the control precision of the 3D printer.

[0083] 2. The invention improves the accuracy of the data of the 3D printer by obtaining the topological information of all triangular facets in the STL format file, numbering them based on the obtained topological information, slicing the numbered three-dimensional model by setting a height, determining the profile of the cutting plane, collecting the determined cutting plane profiles, arranging them in reverse order according to the cutting plane height, outputting the information on the number of cutting planes generated after slicing, and transmitting the output data to the 3D printer.

[0084] 3. The invention monitors the 3D printing process by comparing the material flow rate, detecting the temperature of the 3D printer, and comparing the degree of coincidence of the contour lines to determine the matching degree between the 3D printed three-dimensional model and the cutting plane profile in the processed three-dimensional data, ensuring the accuracy of the 3D printing process.

[0085] 4. The invention continuously adjusts the 3D printed three-dimensional model by the linear interpolation method, establishes a deviation function between the current printing point and the next printing point, and continuously adjusts the 3D printed three-dimensional model based on the calculation result of the deviation function, improving the control accuracy of the D printer. BRIEF DESCRIPTION OF THE DRAWINGS

[0086] Figure 1 It is a schematic structural diagram of the optimization process of the control accuracy of the 3D printer of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0087] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0088] The present invention discloses a method for optimizing the control accuracy of a 3D printer based on feedback control, which specifically includes the following steps:

[0089] 3D printer preparation stage:

[0090] S1. Install a three-dimensional laser scanning device, collect the existing three-dimensional model data through the installed laser device or real-time scan and store the three-dimensional model data of the existing object, and construct a sample set based on the collected or real-time scanned three-dimensional model data;

[0091] Set the formats of collecting the existing three-dimensional model data and real-time scanning and storing the three-dimensional model data of the existing object as STL format files;

[0092] The structure of the STL format file is composed of n triangular facets;

[0093] S2. Process the 3D model data in the constructed sample set to obtain the processed 3D model data, and input the obtained processed 3D model data into a 3D printer;

[0094] Processing the 3D model data in the constructed sample set includes the following steps:

[0095] S21. Obtain the topological information of all triangular facets in the STL format file, and number them based on the obtained topological information;

[0096] Read the number n of triangular facets in the STL format file, select a vertex on the contour of the 3D model data as the initial point, and based on the selected initial point, sequentially traverse the vertex coordinates of each triangular facet;

[0097] Set up a linked list for numbering, and set the triangular facet where the initial point is located as the first number in the linked list;

[0098] Further, when it is detected during the traversal that the two coordinates of two triangular facets are the same, set the two triangular facets with the same two coordinates as adjacent facets;

[0099] Based on the traversal order, insert the number of the later traversed triangular facet after the number of the adjacent facet, and update the number until all triangular facets are traversed;

[0100] S22. Based on the numbered 3D model obtained, slice it by setting a height, and determine the contour of the cutting plane;

[0101] Set the slicing thickness, and slice the 3D model evenly from the bottom upward with a horizontal cutting plane perpendicular to the Z-axis according to the set thickness;

[0102] Further, after slicing is completed, connect the intersecting line segments formed by all triangular facets and the cutting plane to determine the contour of the cutting plane, and calculate all the contours of the cutting plane;

[0103] The calculation formula for the contour of the cutting plane is as follows:

[0104] Set the height of cutting plane 1 as h, and the three vertex coordinates of triangular facet ABC are respectively: A(x 1 ,y 1 ,z 1 ), B(x 2 ,y 2 ,z 2 ), C(x 3 ,y 3 ,z 3 ), and the intersection point coordinates D 1 , D 2 The calculation formula is as follows:

[0105]

[0106] Among them, x represents the abscissa, y represents the ordinate, z represents the vertical coordinate, and h represents the height of the tangent plane;

[0107] S23. Collect the determined tangent plane contours, arrange them in reverse order according to the height of the tangent plane, and output the information on the number of layers of the tangent plane generated after slicing;

[0108] Set the information on the number of layers of the tangent plane generated after slicing as the processed 3D model data, and input the processed 3D model data into a 3D printer;

[0109] 3D printer execution stage:

[0110] S3. Based on the obtained processed 3D data, print through a 3D printer, install an Internet of Things monitoring device in the 3D printer, and collect various parameters of the 3D printer in real time through the installed Internet of Things monitoring device;

[0111] The installed Internet of Things monitoring device includes: a printing image comparison device, a material flow detection device, and a temperature detection device;

[0112] Various parameters of the 3D printer include: material flow and temperature;

[0113] S4. Based on the various parameters of the 3D printer collected in real time, analyze the various parameters of the 3D printer collected in real time through a data analysis algorithm to obtain the analyzed various parameters of the 3D printer;

[0114] S41. Material flow detection and comparison;

[0115] Set the minimum threshold and maximum threshold of the material flow during 3D printing;

[0116] Based on the set threshold and the material flow value detected in real time by the material flow detection device, determine whether the material flow during 3D printing is normal;

[0117] S42. 3D printer temperature detection and comparison;

[0118] Set the maximum threshold of the 3D printer temperature during 3D printing;

[0119] Based on the set threshold and the 3D printer temperature value detected in real time by the temperature detection device, determine whether the 3D printer temperature during 3D printing is normal;

[0120] S43. Model contour detection and comparison:

[0121] S431. Extract the contour image of the projection of the 3D printed three-dimensional model on the projection plane;

[0122] S432. Extract the tangent plane contour from the processed three-dimensional data;

[0123] S433. Match the tangent plane contour extracted from the processed three-dimensional data with the projection contour image of the 3D printed three-dimensional model on the plane;

[0124] S434. Determine the matching degree between the 3D printed three-dimensional model and the tangent plane contour in the processed three-dimensional data according to the coincidence degree of the contour lines;

[0125] Let M(Θ) represent the 3D printed three-dimensional model, the projection image of the 3D printed three-dimensional model on the two-dimensional plane be m(M(Θ)), and the tangent plane contour image extracted from the processed three-dimensional data be P m(M(Θ)) ; For the input three-dimensional model D, the contour image obtained after contour extraction is P D ; Use the similarity function S(Θ) to judge the contour images P m(M(Θ)) 、P D 's coincidence degree;

[0126]

[0127] Among them, Q 0 (Θ) is the area of the overlapping part of the two contours P m(M(Θ)) and P D , Q(C m(M(Θ)) ) and Q(P D ) are the areas of the corresponding contours respectively; 0 ≤ S ≤ 1, the larger S is, the more similar the two regions are, and when the two regions overlap, S = 1;

[0128] Set the matching degree threshold between the 3D printed three-dimensional model and the tangent plane contour in the processed three-dimensional data;

[0129] S5. Perform real-time control based on the analyzed parameters of the 3D printer obtained;

[0130] S51. Perform real-time control on the 3D printer based on the detection and comparison of the material flow rate;

[0131] When the material flow rate value detected by the material flow rate detection device in real time is less than or equal to the set minimum material flow rate threshold, stop printing and detect whether there is a blockage in the material supply pipe of the 3D printer;

[0132] When the material flow rate value detected by the material flow rate detection device in real time is greater than or equal to the set maximum material flow rate threshold, reduce the material flow rate by adjusting the pressure of the material supply pipe of the 3D printer;

[0133] S52. Real-time control of the 3D printer based on temperature detection and comparison of the 3D printer;

[0134] When the temperature value of the 3D printer detected in real time by the temperature detection device is greater than or equal to the maximum threshold of the set 3D printer temperature, stop printing;

[0135] S53. Real-time control of the 3D printer based on model contour detection and comparison;

[0136] When the 3D printed three-dimensional model does not coincide with the cutting plane contour in the processed three-dimensional data, continuously adjust the 3D printed three-dimensional model according to the similarity degree until the contour image areas coincide;

[0137] Continuously adjusting the 3D printed three-dimensional model according to the similarity degree includes the following steps:

[0138] Continuously adjust the 3D printed three-dimensional model by the linear interpolation method;

[0139] Set the current printing point coordinates of the 3D printed three-dimensional model as w(x w , y w ), the next printing point coordinates as e(x e , y e ), and the deviation function F w of the printing point is expressed as follows:

[0140] F w = y w x e - x w y e

[0141] When the calculated deviation function F w = 0 of the printing point, it means that the current printing point is printed correctly. When the calculated deviation function F w > 0 of the printing point, it means that the current printing point is printed too high, and then adjust it in the positive x-axis direction. When the calculated deviation function F w < 0 of the printing point, it means that the current printing point is printed too low, and then adjust it in the positive y-axis direction;

[0142] The present invention also discloses a 3D printer control precision optimization system based on feedback control, including a feeding pipe, a material flow detection device, a printing image comparison device, a temperature detection device, a three-dimensional laser scanning device, a model slicing module, a contour determination module, and a printer analysis and control module;

[0143] The three-dimensional laser scanning device is used to collect existing three-dimensional model data in real time or scan and store the three-dimensional model data of an existing object in real time;

[0144] The model slicing module is used to slice the collected three-dimensional model data at a set height;

[0145] The contour determination module is used to determine the cutting plane contour data of each layer of the three-dimensional model after slicing;

[0146] The material conveying pipe is used to convey materials into the 3D printer;

[0147] The material flow detection device is used to monitor the material conveying flow rate of the material conveying pipe in real time;

[0148] The temperature detection device is used to monitor the temperature change of the 3D printer in real time;

[0149] The printing image comparison device is used to compare the cutting plane contour in the three-dimensional data with the projected contour image of the 3D printed three-dimensional model on a plane;

[0150] The printer analysis and control module is used to control the 3D printer according to the analysis and comparison results.

[0151] Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principle and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A 3D printer control accuracy optimization method based on feedback control, characterized in that: The following steps are involved: S1. Install a 3D laser scanning device, collect existing 3D model data or scan and store 3D model data of existing objects in real time through the installed laser device, and build a sample set based on the collected or real-time scanned 3D model data; S2, processing the three-dimensional model data in the construction sample set to obtain processed three-dimensional model data, and inputting the obtained processed three-dimensional model data into the 3D printer; S3, printing the processed three-dimensional model data through a 3D printer, installing an Internet of Things monitoring device in the 3D printer, and collecting various parameters of the 3D printer in real time through the installed Internet of Things monitoring device; S4, based on the various parameters of the 3D printer collected in real time, analyzing the various parameters of the 3D printer collected in real time through a data analysis algorithm to obtain the analyzed various parameters of the 3D printer; S5, performing real-time control on various parameters of the 3D printer based on the analysis; The step of constructing a sample set based on the collected or real-time scanned three-dimensional model data comprises the following steps: Set the format of collecting existing 3D model data and real-time scanning and storing the 3D model data of existing objects to be STL format files; The structure of the STL format file is composed of n triangular facets; The processing of the three-dimensional model data in the sample set comprises the following steps: S21, obtaining topological information of all triangular facets in the STL format file, and numbering them based on the obtained topological information; S22, based on the obtained numbered three-dimensional model, slicing is performed by setting a height, and a cutting plane contour is determined; S23, collecting the determined cutting plane contours, arranging them in reverse order according to the cutting plane heights, and outputting the cutting plane layer number information generated after slicing; Setting the information of the number of cutting plane layers generated after the output slicing as processed three-dimensional model data, and inputting the processed three-dimensional model data into the 3D printer; The method of analyzing the various parameters of the 3D printer collected in real time by a data analysis algorithm comprises the following steps: S41, material flow detection comparison; Set the minimum and maximum thresholds for material flow during 3D printing; Based on the set threshold, the material flow value detected in real time by the material flow detection device is compared to determine whether the material flow during 3D printing is normal; S42, 3D printer temperature detection comparison; Set the maximum threshold of the 3D printer temperature during 3D printing; Based on the set threshold, the temperature value of the 3D printer detected in real time by the temperature detection device is compared to determine whether the temperature of the 3D printer is normal during the 3D printing process; S43, model contour detection and comparison; The model contour detection and comparison comprises the following steps: S431, extracting a contour image of the projection of the 3D-printed three-dimensional model on the projection plane; S432, extracting the cutting plane contour in the processed three-dimensional data; S433, matching the cut plane contour in the extracted three-dimensional data with the contour image of the 3D printed three-dimensional model projected on the plane; S434, judging the matching degree between the 3D printed three-dimensional model and the cutting plane contour in the processed three-dimensional data according to the overlap degree of the contour lines; Assume that M(Θ) represents the 3D printed three-dimensional model, the projection image of the 3D printed three-dimensional model on the two-dimensional plane is m(M(Θ)), and the contour image of the cutting plane in the extracted three-dimensional data is P m(M(Θ)) ; For the input 3D model D, the contour image obtained after contour extraction is P D ; Use the similarity function S(Θ) to judge the contour image P m(M(Θ)) , P D degree of overlap; Among them, Q0(θ) is the two contours P m(M(Θ)) With P D The area of ​​the overlapped part, Q(P m(M(Θ)) ) and Q(P D ) are the areas of the corresponding contours; 0≤S≤1, the larger S is, the more similar the two regions are. When the two regions overlap, S=1; Setting a threshold for the matching degree between the 3D printed 3D model and the cutting plane contour in the processed 3D data; The real-time control of the various parameters of the 3D printer based on the analysis comprises the following steps: S51, real-time control of 3D printer based on material flow detection comparison; When the material flow value detected in real time by the material flow detection device is less than or equal to the set material flow minimum threshold, printing is stopped to detect whether the material delivery pipe of the 3D printer is blocked; When the material flow value detected in real time by the material flow detection device is greater than or equal to the set material flow maximum threshold, the material flow is reduced by adjusting the pressure of the 3D printer feed pipe; S52, controlling the 3D printer in real time based on the 3D printer temperature detection comparison; When the temperature value of the 3D printer detected in real time by the temperature detection device is greater than or equal to the maximum threshold value of the set 3D printer temperature, printing is stopped; S53, real-time control of 3D printer based on model contour detection and comparison; When the 3D printed three-dimensional model does not coincide with the cut plane contour in the processed three-dimensional data, the 3D printed three-dimensional model is continuously adjusted according to the degree of similarity until the contour image area coincides; Based on the degree of similarity, the 3D printed 3D model is continuously adjusted, including the following steps: Continuously adjust the 3D printed 3D model through linear interpolation; Set the current printing point coordinates of the 3D printed 3D model to w(x w ,y w ), the coordinates of the next printing point are e(x e ,y e ), the deviation function F of the printed point w The expression is as follows: F w =y w x e -x w y e When the calculated print point deviation function F w = 0, it means that the current printing point is printed correctly. When the calculated deviation function F of the printing point w >0, it means that the current printing point is printed upward, and then adjusted in the positive direction of the x-axis. When the calculated deviation function F of the printing point w When <0, it means that the current printing point is printed downward and then adjusted in the positive direction of the y-axis.

2. The method for optimizing the control accuracy of a 3D printer based on feedback control according to claim 1, characterized in that: The step of obtaining the topological information of all triangular facets in the STL format file and numbering them based on the obtained topological information comprises the following steps: Read the number of triangle patches n in the STL format file, select the vertex on the 3D model data outline as the initial point, Based on the selected initial point, traverse the vertex coordinates of each triangle patch in turn; Set a linked list for numbering, and set the triangle patch where the initial point is located as the first number in the linked list; When it is detected during the traversal process that the two coordinates of two triangular patches are the same, the two triangular patches with the same coordinates are set as adjacent patches; Based on the traversal order, the numbers of the triangle patches traversed later are inserted after the numbers of the adjacent patches, and the numbers are updated until all the triangle patches are traversed.

3. The method for optimizing the control accuracy of a 3D printer based on feedback control according to claim 2, characterized in that: The method of slicing the obtained numbered three-dimensional model by setting a height and determining a cutting plane contour comprises the following steps: Set the slice thickness, and slice the 3D model evenly from the bottom to the top along the cross-section plane perpendicular to the Z axis according to the set thickness; When the slicing is completed, all the intersecting line segments formed by the triangle facets and the cutting plane are connected to each other, the cutting plane contour is determined, and all the cutting plane contours are calculated; The cutting plane contour calculation formula is as follows: Set the height of cutting plane 1 to h, the coordinates of the three vertices of triangle patch ABC are: A(x1, y1, z1), B(x2, y2, z2), C(x3, y3, z3), the calculation formula of the intersection coordinates D1 and D2 of cutting plane 1 and triangle patch ABC is as follows: Among them, x represents the horizontal coordinate, y represents the vertical coordinate, z represents the vertical coordinate, and h represents the height of the tangent plane.

4. The method for optimizing control accuracy of a 3D printer based on feedback control according to claim 1, characterized in that: The real-time collection of various parameters of the 3D printer by the installed IoT monitoring device includes: The installed IoT monitoring equipment includes: print image comparison equipment, material flow detection equipment and temperature detection equipment; The parameters of 3D printers include: material flow and temperature.

5. A system for implementing the 3D printer control accuracy optimization method based on feedback control according to any one of claims 1 to 4, characterized in that: It includes a material conveying pipe, a material flow detection device, a printing image comparison device, a temperature detection device, a 3D laser scanning device, a model slicing module, a contour determination module and a printer analysis and control module; The three-dimensional laser scanning device is used to collect existing three-dimensional model data in real time or scan and store the three-dimensional model data of existing objects in real time; The model slicing module is used to slice the collected three-dimensional model data according to a set height; The contour determination module is used to determine the cutting plane contour data of each layer of the three-dimensional model after segmentation; The material delivery pipe is used to deliver the material into the 3D printer; The material flow detection device is used to monitor the material conveying flow of the conveying pipe in real time; The temperature detection device is used to monitor the temperature change of the 3D printer in real time; The printed image comparison device is used to compare the cut plane contour in the three-dimensional data with the contour image projected on the plane by the 3D printed three-dimensional model; The printer analysis control module is used to control the 3D printer according to the analysis and comparison results.

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