How to generate corrective helmet manufacturing data

Abstract

To provide a method of creating data for producing a correction helmet capable of producing a required correction helmet by applying required processing to correction target cranial shape data of a patient and supplying the processed data to a three-dimensional printer.SOLUTION: A method of creating data for producing a correction helmet intended to correct a deformed cranium by using a three-dimensional printer, comprises: an input step of incorporating correction target cranial shape data representing a correction target cranial shape into three-dimensional CAD software and creating mesh data representing correction target cranial surface shape; an offset step of offsetting the mesh data by a predetermined amount in an expanding direction; a ridding step of ridding an unnecessary part from the mesh data; a thickness adding step of adding a predetermined thickness to the mesh data; and an output step of outputting, in the stl format, the mesh data that are offset in the expanding direction, rid of the unnecessary part, and added with the thickness.SELECTED DRAWING: Figure 1-1

Description

[Technical Field]

[0001] The present invention relates to a method for generating corrective helmet manufacturing data for manufacturing a corrective helmet for correcting a deformed skull using a three-dimensional printer. [Background technology]

[0002] Patent Document 1 listed below discloses a corrective helmet for correcting the deformed skull of a patient (usually an infant). It is important that such a corrective helmet be manufactured to an optimal shape that corresponds to the deformed skull of each individual patient by recognizing the skull shape of the individual patient. Meanwhile, Patent Document 2 listed below conceptually discloses a method of determining ideal skull shape data based on three-dimensional scan data showing the skull shape of an infant, and then manufacturing a corrective helmet based on the ideal skull shape data. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 6333514 [Patent Document 2] U.S. Patent No. 6,340,353 Summary of the Invention [Problem to be solved by the invention]

[0004] While Patent Document 1 discloses the production of a corrective helmet using a three-dimensional printer, it does not describe what kind of data is input into the three-dimensional printer to produce the corrective helmet. Meanwhile, Patent Document 2 conceptually describes, as mentioned above, determining ideal cranial shape data based on three-dimensional scan data showing the patient's cranial shape and producing a corrective helmet based on the ideal cranial shape data, but it does not describe what specific processing is performed on the ideal cranial shape data to generate the data to be supplied to the three-dimensional printer.

[0005] The present invention was made in light of the above-mentioned circumstances, and its main technical problem is to provide a new and improved method for performing the required processing on a patient's corrective target cranial shape data (such corrective target cranial data does not necessarily match ideal cranial shape data, and for example, in the case of an excessively deformed skull, it is not always appropriate to correct the skull to the ideal shape), and generating corrective helmet production data that can be supplied to a three-dimensional printer to enable the production of the required corrective helmet. [Means for solving the problem]

[0006] After extensive research, the inventors discovered that the above-mentioned main technical objective can be achieved by importing the data of the corrected target skull shape indicating the corrected target skull shape into appropriate three-dimensional CAD (Computer Aided Design) software and subjecting such data to appropriate processing.

[0007] That is, according to the present invention, the method for achieving the above-mentioned main technical object is as follows: A method for generating corrective helmet manufacturing data for manufacturing a corrective helmet for correcting a deformed skull using a three-dimensional printer, comprising: an input step of importing correction target cranial shape data indicating the correction target cranial shape into three-dimensional CAD software and generating mesh data indicating the correction target cranial surface shape; an offsetting step of offsetting the mesh data by a predetermined amount in an enlargement direction; a deletion step of deleting unnecessary portions from the mesh data; a thickness imparting step of imparting a predetermined amount of thickness to the mesh data; an output step of outputting the mesh data that has been offset in the enlargement direction, has unnecessary portions deleted, and has thickness added; A method is provided comprising:

[0008] Preferably, the deletion step is performed after the offset step, and the thickness imparting step is performed after the deletion step. Preferably, after the input step and before the offset step, an auricle processing step is included, which includes: forming hollowing curves for hollowing out the left and right auricles based on auricle tracing curves that trace the left and right auricles, connecting the left and right hollowing curves to form a hollowing surface, hollowing out the mesh data using the hollowing surface, and filling the hollowed-out portion with a mesh that defines a smoothly connected surface around the periphery. The deletion step preferably includes offsetting the auricle tracing curve by a predetermined amount in the expansion direction, forming a front cut surface based on the offset auricle tracing and the serion, cutting using the front cut surface, cutting below a predetermined collar height, rounding sharp portions generated by the cutting, and generating a cut cylinder that is a cylinder centered on the center point of the skull top surface, and cutting using the cut cylinder. It is desirable to include a lift-up extension step, after the deletion step and before the output step, of adding a lift-up extension mesh that extends the lift-up portion downward by a predetermined amount. Preferably, it is desirable to include a slit forming step, after the cutting step and before the output step, of forming a slit that extends continuously from the upper edge to the lower edge adjacent to the one-side lift-up portion and rounding any sharp portions created by forming the slit. It is preferable to include a ventilation hole forming step, after the deletion step and before the output step, of forming a plurality of ventilation holes at intervals in a main area excluding an outer peripheral area of ​​a predetermined width from the outer peripheral edge of the mesh data. It is desirable to include a round bar joining step, after the slit forming step and before the output step, of forming a solid round bar of a predetermined diameter that extends continuously along the outer peripheral edge of the mesh data except for the area where the slit exists, joining the round bar to the mesh data, and rounding the joined portion. It is desirable to include a display forming step, before the output step, of forming a display containing letters and / or symbols in a predetermined portion of the mesh data. In the output step, it is convenient to output the mesh data in stl format. [Effects of the Invention]

[0009] According to the present invention, the patient's corrective target skull shape data is input into three-dimensional CAD software, and the required processing is performed to generate corrective helmet production data that can be supplied to a three-dimensional printer to produce the required corrective helmet. [Brief explanation of the drawings]

[0010] [Figure 1-1] 1 is a portion of a flowchart illustrating a preferred embodiment of a method of the present invention for generating corrective helmet manufacturing data for correcting a deformed skull using a three-dimensional printer. [Figure 1-2] 1 is a portion of a flowchart illustrating a preferred embodiment of a method of the present invention for generating corrective helmet manufacturing data for correcting a deformed skull using a three-dimensional printer. [Figure 2] Schematic diagram of mesh data showing the target skull surface shape for correction. [Figure 3] Schematic diagram showing the trace curve of the pinna. [Figure 4] 4 is a schematic diagram showing a hollowed-out surface formed based on the trace curve of FIG. 3; [Figure 5] Schematic diagram showing the hollowed-out state using the hollowed-out surface shown in Figure 4. [Figure 6] 5 is a schematic diagram showing interpolated mesh data in which the cutout portion shown in FIG. 4 is filled with a mesh that defines a smooth surface. [Figure 7] FIG. 4 is a schematic diagram showing offset mesh data. [Figure 8] Schematic diagram showing the front cut surface. [Figure 9] Schematic diagram showing front cut mesh data. [Figure 10] FIG. [Figure 11] Schematic diagram showing lower cut mesh data. [Figure 12] Schematic diagram showing a cut cylinder. [Figure 13] Schematic diagram showing mesh data for a top surface cutout. [Figure 14] Schematic diagram showing mesh data for kneading extension. [Figure 15]FIG. 10 is a schematic diagram showing slit formation mesh data. [Figure 16] FIG. 10 is a schematic diagram showing ventilation holes generated in mesh data. [Figure 17] Schematic diagram showing mesh data for producing a corrective helmet. DETAILED DESCRIPTION OF THE INVENTION

[0011] A preferred embodiment of the method of the present invention for generating corrective helmet manufacturing data for correcting a deformed skull using a three-dimensional printer will now be described in more detail with reference to the accompanying drawings.

[0012] Referring to the flowchart shown in FIG. 1, in step n-1, the correction target cranial shape data indicating the correction target cranial shape is input into three-dimensional CAD software installed on a computer, and mesh data 2 indicating the correction target cranial shape is generated (input step). The three-dimensional CAD software may be any suitable type that is commercially available, and for example, the "Grasshopper" function in three-dimensional CAD software sold under the product name "Rhinoceros" is used. can be preferably used. The corrective target cranial shape data can be generated by three-dimensionally scanning the patient's skull (usually the area above the patient's neck, including the skull) to identify deformations in the patient's skull shape and determining how to correct such deformations. For example, the data can be conveniently generated by the method disclosed in the specification and drawings of the patent application filed by the applicant on the same date as this application (titled "Method for Determining Corrective Target Cranial Shape"). Figure 2 shows a schematic diagram of the corrective target cranial shape represented by the generated mesh data 2. In step n-1, it is desirable to also incorporate information indicating the center point of the top surface of the skull (shown by triangle A in Figure 2) and information indicating the height of the cerion (shown by triangle B in Figure 2) along with the mesh data (the use of this information, i.e., triangles A and B, will be discussed further below).

[0013] In step n-2, the left and right pinnae are traced to generate pinna tracing curves 4 (FIG. 3). Next, in step n-3, as shown in FIG. 4, hollowing curves (closed endless curves) for hollowing out the left and right pinnae are generated based on the pinna tracing curves 4, and the left and right hollowing curves are connected to generate hollowing surfaces 6, and the mesh data 2 is hollowed out using the hollowing surfaces 6 (FIG. 5). Thereafter, in step n-4, the portions 8 hollowed out by the hollowing surfaces 6 are filled with meshes 10 that define surfaces that are smoothly connected to the surrounding areas, thereby forming filled mesh data 12. The processing in steps n-2 to n-4 is intended to prevent subsequent processing from becoming complicated due to the presence of protruding pinnae.

[0014] Next, in step n-5, the interpolated mesh data 12 is offset by a predetermined amount in the enlargement direction. The operator uses the 3D CAD software installed on the computer. Input the offset mesh data 14 after offsetting. Figure 7 shows the offset mesh data 14 after offsetting, and the shape shown in Figure 7 is enlarged by a predetermined amount compared to the shape shown in Figure 6. As disclosed in Patent Document 1, the main body (i.e., shell) of a corrective helmet is conveniently formed from an appropriate synthetic resin by powder sintering layer deposition using a three-dimensional printer, and it is desirable that a liner made from foamed synthetic resin or the like is disposed on the inner surface of the corrective helmet formed in this manner. The offset in step n-5 takes into consideration the thickness of the liner disposed on the inner surface of the main body of the corrective helmet. It is preferable that the offset amount be a value slightly smaller than the thickness of the liner. R .

[0015] On the other hand, in step n-6, the pinna trace curve 4 generated in step n-2 is offset by a predetermined amount in the expansion direction. The operator uses the 3D CAD software installed on the computer.Next, in step n-7, as shown in Fig. 8, based on the offset pinna tracing curve and the serion (triangle B in Fig. 2) acquired in step n-1, a front cut surface 16 is generated by preferably combining the offset pinna tracing curve and a horizontal plane passing through the serion. Then, in step n-8, the offset mesh data 14 is cut out using the front cut surface 16. Fig. 9 shows front cut mesh data 18 formed by cutting the offset mesh data 14 with the front cut surface 16. In step n-9, as shown in Figs. 10 and 11, a portion of the front cut mesh data 18 below a horizontal plane 20 passing through a predetermined collar height is cut out to form lower cut mesh data 22. The horizontal plane 20 at the predetermined height is appropriately set based on the target corrected skull shape. The operator uses the 3D CAD software installed on the computer. In step n-10, sharp portions of the lower cut mesh data 22 generated by the cuts in steps n-8 and n-9 are rounded. Next, in step n-11, as shown in Figures 12 and 13, a cut cylinder 24 is generated, which is a cylinder of diameter d centered on the center point of the top surface of the target corrected skull shape (see triangle A in Figure 2), and is preferably tilted downward and backward at a predetermined tilt angle α. This cut cylinder 24 is used to create an opening 26 by hollowing out the center of the skull top surface that is not the target of deformed skull correction, and top surface hollowed-out mesh data 28 is formed. The diameter d may be approximately 10 cm. The tilt angle α is set appropriately based on the target corrected skull shape. The operator uses the 3D CAD software installed on the computer. Thus, steps n-6 to n-10 constitute a deletion step for deleting unnecessary portions from the offset mesh data 14. If desired, step n-5 (mesh offset step) can be performed after steps n-6 to n-10 (deletion step).

[0016] In step n-12, the massaged portion is tilted downward, forward or backward by a predetermined angle β as required, and extended by a predetermined amount, thereby generating massaged portion extension mesh data 30 (massage extension step). The downward extension amount X of the massaged portion and the tilt angle β are appropriately set according to the target corrected skull shape. The operator uses the 3D CAD software installed on the computer. The extension of the massaged portion helps the infant to wear the helmet more stably. Next, in step n-13, a predetermined thickness t is assigned to the massaged portion extension mesh data 30 (FIG. 14) (thickness assignment step). The thickness t, which corresponds to the thickness of the corrective helmet body (shell) to be manufactured, may be about 3.0 mm. The operator uses the 3D CAD software installed on the computer. Next, in step n-14, a slit 32 is formed adjacent to the rear edge of the massaged part, extending continuously from the upper end to the lower end, and then in step n-15, the sharp portion created by forming the slit 32 is rounded (slit forming step).Thus, mesh data 34 is formed in which thickness is added and the slit 32 is formed.

[0017] In step n-16, as shown in FIG. 16, a plurality of ventilation holes 36 are generated at predetermined intervals in an area about 10 to 20 mm inward from the outer periphery of the mesh data 34 (ventilation hole forming step). The number, arrangement, shape and dimensions of the ventilation holes 36 are set appropriately. The operator uses the 3D CAD software installed on the computer. Enter.

[0018] Meanwhile, in step n-17, the outer periphery of the mesh data 34 is extracted. Next, in step n-18, the length of the outer periphery of the opening 26 formed on the top surface, excluding the slit 32, that extends continuously, and the length of the other outer peripheries of the mesh data 34 (i.e., excluding the outer periphery of the opening 26), excluding the slit 32, that extend continuously, are calculated. At this time, the intervals of the interrupted portions in the slit 32 portion are appropriately selected. The operator uses the 3D CAD software installed on the computer. input doIn step n-19, two solid round bars 38 (see FIG. 17) of the length calculated in step n-18 are formed. The diameter of the solid round bars 38, which constitute the thick reinforcing portion reinforcing the outer periphery of the corrective helmet, may be approximately 6 mm. Next, in step n-20, one solid round bar 38 is connected to the mesh data 34 so that it extends continuously around the outer periphery of the opening 26 formed in the top surface, except for the slit 32, and the other solid round bar 38 is connected to the mesh data 34 so that it extends continuously around the other outer periphery of the mesh data 34 (i.e., excluding the outer periphery of the opening 26), except for the slit 32. In step n-21, the joints of the solid round bars 38 are smoothed to form a smooth connection. In this way, mesh data 40 for producing the corrective helmet is generated, as shown in FIG. 17. Steps n-17 to n-21 constitute a round bar joining process.

[0019] In the illustrated embodiment, furthermore, in step n-22, a mark (not shown) containing letters and / or symbols indicating the ID data and / or an appropriate trademark of the corrective helmet is formed (mark forming step). Such a mark may be in the form of a local cutout of the mesh data 40 or a local scraping off of the front or back surface of the mesh data 40. The mark to be formed is The operator uses the 3D CAD software installed on the computer. input vinegar do.

[0020] In step n-23, the mesh data 40 is output to a three-dimensional printer (not shown) in an STL format suitable for producing a corrective helmet with a three-dimensional printer. Then, a corrective helmet of the required shape is produced with the three-dimensional printer. [Explanation of symbols]

[0021] 2: Mesh data showing the target corrected skull shape 4: Pinna tracing curve 6: Hollowed out surface 8: Hollowed out part 10: Compensation mesh section 12: Compensation mesh data 14: Offset mesh data 16: Front cut surface 18: Front cut mesh data 20: A horizontal plane passing through a specified collar height 22: Bottom cut mesh data 24: Cut cylinder 26: Top surface cutout opening 28: Mesh data for top surface hollowing 30: Sideburn extension mesh data 32: Slit 34: Mesh data with thickness added and slits formed 36: Ventilation hole 38: Round bar 40: Mesh data for making corrective helmets

Claims

1. A method for generating corrective helmet production data for producing a corrective helmet for correcting a deformed skull, the corrective helmet having a main body and a liner disposed on the inner surface of the main body, using a three-dimensional printer, by a computer having three-dimensional CAD software installed therein, an input step of inputting the correction target cranial shape data indicating the correction target cranial shape and information indicating the center point of the cranial summit surface and the height of the cerion into three-dimensional CAD software, and generating mesh data indicating the correction target cranial surface shape; an offsetting step of offsetting the mesh data by a predetermined amount in an enlargement direction; a deletion step of deleting unnecessary portions from the mesh data; a thickness imparting step of imparting a predetermined amount of thickness to the mesh data; an output step of outputting the mesh data that has been offset in the enlargement direction, has unnecessary portions deleted, and has thickness added; Including, the predetermined amount in the offset step is smaller than the thickness of the liner; The method is characterized by including, after the input step and before the offset step, an auricle processing step of forming hollowing curves for hollowing out the left and right auricles based on auricle tracing curves that trace the left and right auricles, connecting the left and right hollowing curves to form a hollowing surface, and hollowing out the mesh data using the hollowing surface.

2. 2. The method according to claim 1, further comprising a round bar joining step of extracting an outer periphery of the mesh data, calculating a length that extends continuously around the outer periphery of the mesh data, forming a solid round bar of the calculated length, and joining the solid round bar to the mesh data so that the solid round bar extends continuously around the outer periphery of the mesh data.

3. 3. The method of claim 1 or 2, wherein the deletion step includes offsetting the pinna tracing curve by a predetermined amount in the expansion direction, forming a front cut surface based on the offset pinna tracing and the serion, and cutting with the front cut surface, cutting downward from a predetermined collar height, rounding sharp portions created by the cutting, and creating a cut cylinder centered on the center point of the skull top surface and inclined downward and posteriorly by a predetermined angle, and cutting with the cut cylinder.

4. The method according to any one of claims 1 to 3, further comprising a step of adding a massage extension mesh that extends the massaged portion downward by a predetermined amount after the removing step and before the outputting step.

5. 5. The method according to claim 1, further comprising, after the removing step and before the outputting step, a slit forming step of forming a slit adjacent to the one-side massaged portion, the slit extending continuously from the upper edge to the lower edge, and rounding off any sharp portions produced by forming the slit.

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