JP5408221B2 - Solid object shaping apparatus and control program - Google Patents

Description

  The present invention relates to a three-dimensional object modeling apparatus and a control program, and more particularly, to a three-dimensional object modeling apparatus that models a three-dimensional object with adjusted weight balance and a control program that controls modeling of a three-dimensional object with adjusted weight balance.

  A technique called rapid prototyping (RP) is known as a technique for modeling a three-dimensional solid object. This technology calculates the cross-sectional shape sliced thinly in the stacking direction based on the data (STL (Standard Triangulated Language) format data) that describes the surface of one three-dimensional shape as a collection of triangles. It is a technology to form and form a three-dimensional object. In addition, as a technique for modeling a three-dimensional object, a melt deposition method (FDM: Fused Deposition Molding), an ink jet method, an ink jet binder method, a stereolithography method (SL: Stereo Lithography), a powder sintering method (SLS: Selective Laser Sintering) ) Etc. are known.

  As an apparatus for modeling a three-dimensional object using such a technique, for example, in Patent Document 1 below, a three-dimensional one in which a binder such as polyethylene and a metal alloy such as stainless steel or titanium are previously compounded at a desired ratio. An apparatus for modeling a three-dimensional object is disclosed. In addition, products that have a plurality of heads capable of injecting a modeling material, and that are modeled by appropriately injecting different materials from the individual heads are also on the market. In this product, different modeling materials can be selectively injected from different heads for modeling, and a three-dimensional object can be modeled by changing colors and textures depending on the modeling material in regions or parts.

Japanese Patent No. 3433219

  Stable independence is an important factor for a modeled object, especially a modeled object for display purposes. Conventionally, when designing 3D data using 3D-CAD (Computer Aided Design), etc. The data itself is made into a weight-balanced outer shape, or a cavity is provided inside it, and the 3D printer side, including the internal structure, faithfully shapes the entered internal and external shapes, so that it can stand on its own. I had a model to do.

  As described above, the conventional 3D printer is specialized in faithfully reproducing the 3D shape and has no function of adjusting the weight balance at the time of modeling, so that “the ground contact area is small”, “inclined”, etc. Due to the reason for the shape of the modeled object, the modeled object may be unstable and not self-supporting, or may be easily overturned.

  In addition, since it is a shape that does not stand on its own with the model body, when modeling a model to be installed on a display stand (support stand) that is integral with or separate from the model, the support point of the model body by the display stand is It is difficult to correctly match the part (center of gravity position) that can stably support the body of the model, and if the support point is set with priority given to the aesthetics at the time of display, the support point will deviate from the center of gravity position and become unstable. There was a thing. Also, when modeling a model to be hung, it is difficult to correctly match the hanging position to the part (center of gravity) where the model body can be stabilized, giving priority to the aesthetics at the time of display. When the suspension position is set, the support point may deviate from the center of gravity and become unstable. Furthermore, when modeling a model with a movable part, the balance may be lost depending on the arrangement of the movable part, and the independence may become unstable.

  This invention is made | formed in view of the said problem, Comprising: The main objective is modeling the solid object which can model the solid object which adjusted the weight balance, and the solid object which adjusted the weight balance. It is to provide a control program for controlling.

  In order to achieve the above object, the present invention is used for modeling in a three-dimensional object modeling apparatus that models a three-dimensional object by sequentially stacking modeling materials, and a data input unit that inputs three-dimensional shape information of a modeling object. A modeling object having the same shape as the modeling object based on a modeling material database storing weight information per unit volume of one or more modeling materials and shape information of the modeling object acquired from the data input unit The weight balance calculation unit that calculates the weight distribution for each part of the modeled object, in which the modeled object is in a stable state with respect to a specific support direction, and the model acquired from the data input unit Shape information of the object, weight distribution information calculated by the weight balance calculation unit, weight information of the one or more modeling materials acquired from the modeling material database, Based on the modeling, a filling rate representing the degree of density of the modeling material or a mixing ratio of a plurality of modeling materials is calculated for each part of the modeling object, and the modeling material is laminated according to the calculated filling rate or the mixing ratio. A modeling parameter generation unit that generates information and a modeling unit that stacks the modeling material according to the modeling information are provided.

  Further, the present invention is a control program that operates in a three-dimensional object modeling apparatus that models a three-dimensional object by sequentially stacking modeling materials, or a control device that controls the three-dimensional object modeling apparatus, Based on the shape information of the modeling object acquired from the data input part which inputs the three-dimensional shape information of the modeling object, and the data input part, the control device has the same shape as the modeling object. The modeling object acquired from the data input unit, the weight balance calculation unit for calculating the weight distribution for each part of the modeled object, in which the center of gravity position is obtained and the modeled object is in a stable state with respect to a specific support direction Shape information, weight distribution information calculated by the weight balance calculation unit, and weight information per unit volume of one or more modeling materials used for modeling stored in advance In order to calculate the filling rate representing the degree of density of the modeling material or the mixing ratio of a plurality of modeling materials for each part of the modeling object, and to stack the modeling material according to the calculated filling rate or mixing ratio It functions as a modeling parameter generation unit that generates modeling information.

  According to the three-dimensional object modeling apparatus and the control program of the present invention, a three-dimensional object with an adjusted weight balance can be modeled.

  The reason is that the three-dimensional object modeling apparatus (control program) acquires the shape information of the modeled object based on the 3D data of the modeled object, obtains the center of gravity position of the modeled object based on this shape information, and is instructed in advance. The weight distribution for each part that is in a stable state with respect to the support conditions is calculated, and based on the shape information, the weight distribution information, and the weight information of the modeling material, the filling rate of the modeling material for each part or a plurality of modeling materials This is because the mixing ratio is calculated and modeling information for modeling each layer is generated.

  As a result, even a modeled object with a small ground contact surface or a modeled object that is inclined and unstable can be made to stand on its own. Moreover, even if it is a molded object of the form mounted in a display stand, it can be supported with the balance at the support point of a display stand. In addition, even a shaped object that is hung can be hung with good balance in a desired direction. Furthermore, even a modeled object with a movable part can be made to stand on its own in various forms.

It is a figure which classify | categorizes and demonstrates the method of adjusting the weight balance of a molded article. It is a figure which shows the example of the structure for adjusting a weight balance by density. It is a figure which shows typically the structure of the head in the case of adjusting a weight balance using a some modeling material. It is a block diagram which shows the structure of the three-dimensional object modeling apparatus which concerns on one Example of this invention. It is a flowchart figure which shows the modeling procedure (when adjusting a weight balance) of the solid thing which concerns on one Example of this invention. It is a figure explaining the weight balance of the inclined modeling thing. It is a figure explaining how to obtain | require a gravity center position. It is a figure explaining the method to adjust the weight balance of the inclined molded article. It is a figure which shows the support range which should respond | correspond with the gravity center position which maintains weight balance. It is a flowchart figure which shows the procedure which adjusts to the gravity center position which maintains a weight balance. It is a figure which shows the gravity center position which maintains the stable weight balance. It is a flowchart figure which shows the procedure which adjusts to the gravity center position which maintains the stable weight balance. It is a figure which shows an example of the molded article supported by one point. It is a figure which shows an example of the molded article supported by multiple points. It is a figure which shows an example of the molded article suspended at one point. It is a figure which shows the gravity center position in the case of hanging at multiple points. It is a figure which shows an example of the molded article which becomes independent in a some form (pose). It is a figure which shows an example of the molded article which becomes independent in several forms (state reversed up and down). It is a figure which shows the method of designating a support surface. It is a figure which shows the method of designating a support surface and a support direction. It is a figure which shows the other example of the method of designating a support surface and a support direction. It is a figure which shows the other example of the adjustment method of the weight balance of a present Example. It is a figure which shows the other example of the adjustment method of the weight balance of a present Example. It is a figure which shows typically the conventional method (melting material deposition method) which models a solid thing. It is a figure which shows typically the conventional method (inkjet method) which models a solid thing. It is a figure which shows typically the conventional method (inkjet binder method) which models a solid thing. It is a figure which shows typically the conventional method (optical modeling method) which models a solid thing. It is a figure which shows typically the conventional method (powder sintering method) which models a solid thing.

  As shown in the background art, a technique called rapid prototyping is known as a technique for modeling a three-dimensional solid object, and as a technique for modeling a three-dimensional object, a melt deposition method (FDM) or an ink jet is used. Methods, an ink-jet binder method, an optical modeling method (SL), a powder sintering method (SLS), and the like are known.

  In the melt deposition method (FDM), as shown in FIG. 22, the head piles up the modeling material while moving like a stroke in the layer at the height. For example, a thermoplastic material is heated to be fluidized, and a cross-sectional shape is drawn while being extruded from one nozzle. Further, if necessary, the thermoplastic support material is heated and melted and extruded from the other nozzle. And when the supplied material cools, a thin hardened layer is formed. After repeating this process, a solid object is formed by dissolving the support.

  In the ink jet method, as shown in FIG. 23, the ink is moved in the Y direction while reciprocating in the X direction as in a general paper ink jet printer. For example, a thermoplastic material (build material) is melted by heating and dropped from one inkjet nozzle based on the cross-sectional shape. Further, if necessary, a thermoplastic support material is heated and melted and dropped from the other inkjet nozzle onto the outer periphery or inner periphery of the model. And when the dripped material cools, a thin hardened layer is formed, and the top of the layer is cut each time it is further stacked. By repeating this process, a three-dimensional object is formed and the support is dissolved later.

  Further, in the ink jet binder method, as shown in FIG. 24, after spreading the powder, the binder is dropped on the basis of the cross-sectional shape with an ink jet nozzle, and the powders are bonded together to form a thin solidified layer. And a powder is spread | laid thinly on the solidified layer made, and a solid thing is modeled by repeating this process.

  Further, in the optical modeling method, as shown in FIG. 25, the surface of the resin is hardened and the lower layer is bonded by scanning the resin liquid surface according to the cross-sectional shape with a laser beam. Then, the table is lowered by the thickness of one layer, and this process is repeated to form a three-dimensional object.

  In the powder sintering method, as shown in FIG. 26, the powders are scanned according to the cross-sectional shape with an infrared laser beam after the powders are spread, thereby forming a thin solidified layer. At this time, bonding to the lower layer is also performed by sintering. And a powder is spread | laid thinly on the solidified layer made, and a solid thing is modeled by repeating this process.

  By using such a technique, it is possible to model a three-dimensional object that looks the same as the modeling object. However, these methods are methods for modeling a three-dimensional object using a modeling material having a uniform density, and do not model a three-dimensional object in consideration of weight balance. In some cases, it is impossible to create a model that is stable and independent.

  In order to solve this problem, some products have a plurality of heads capable of injecting a modeling material, and appropriately mold different materials from individual heads to model, for example, when modeling an automobile tire, It is made of hard resin, the tire part is made of rubber-based soft material, or the remote control is made, the case is made of hard resin, and the button part is mixed with rubber-based soft material to reproduce flexibility You can do it. However, this conventional device simply forms the material by specifying the material to be formed for each part, and does not control the weight balance, so it is still possible to create a stable and independent model. I can't.

  Therefore, in one embodiment of the present invention, limited information such as “outer shape”, “support condition”, and “weight per unit volume of modeling material” is used to control the position of the center of gravity of the model during modeling. By doing so, a modeled object that has been unstable in itself, supported, and suspended so far can be maintained in a stable state without being inclined.

  Specifically, a three-dimensional object modeling apparatus that operates by a melt deposition method (FDM) or an ink jet method is provided with a 3D data input unit, a weight balance calculation unit, and a modeling parameter generation unit. Based on the outer shape of the modeling object, the weight balance calculation unit obtains the center of gravity position of the modeling object based on the outer shape information of the modeling object, and the modeling object is in a stable state under the specified support conditions. The modeling parameter generation unit calculates the filling rate of the modeling material for each part by using the outer shape information of the modeling object, the weight distribution information, and the weight information of one or more modeling materials. Alternatively, the mixing ratio is calculated, and modeling information for producing a modeled object is generated according to the calculated filling rate or mixing ratio.

  Thereby, not only an external appearance design but the modeling thing which can be maintained in the stable state can be provided to a user.

  In order to describe the above-described embodiment of the present invention in more detail, a three-dimensional object forming apparatus and a control program according to an embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a diagram illustrating a method for adjusting the weight balance of a modeled object, FIG. 2 is a diagram illustrating an example of a structure for adjusting the weight balance by density, and FIG. 3 is a plurality of modeling materials. It is a figure which shows typically the structure of the head in the case of adjusting a weight balance using. FIG. 4 is a block diagram showing the configuration of the three-dimensional object forming apparatus of the present embodiment, and FIG. 5 is a flowchart showing the three-dimensional object forming procedure of the present embodiment. 6 to 21 are diagrams showing specific examples relating to adjustment of the weight balance.

  In the following examples, an article to be modeled is referred to as a modeling object, and an article that is modeled on the modeling object and is manufactured by a three-dimensional object modeling apparatus is referred to as a modeling object. Moreover, the raw material utilized when producing a modeling thing is called modeling material.

  The filling rate is the ratio of the volume of the modeling material to the unit space volume and represents the degree of density. When the filling rate is less than 100%, the portion other than the modeling material in the space corresponds to a gas such as air, a liquid such as water, or a vacuum. The mixing ratio is a ratio of the volume ratio (filling rate) of each modeling material in the unit space volume and is synonymous with the filling rate ratio. For example, when the filling rate of modeling material A = 20%, the filling rate of modeling material B = 30%, and the filling rate of modeling material C = 50%, the mixing ratio of ABC is 2 to 3 to 5, and the ABC total The filling rate is 100%. Further, when the filling rate of the modeling material A = 20%, the filling rate of the modeling material B = 20%, and the filling rate of the modeling material C = 50%, the mixing ratio of ABC is 2 to 2: 5, and the ABC total The filling rate is 90%.

  When producing a modeling object based on a modeling object, in this embodiment, the weight balance of the modeling object is adjusted by changing the filling rate (roughness / density) or mixing ratio of the modeling material in whole or in part. However, there are various methods for adjusting the weight balance. Hereinafter, a specific description will be given with reference to FIG.

  [Method of partially changing the weight per unit volume of a modeled object using one type of modeling material (see FIG. 1 (a))]

  In the case of this method, the external shape information of the modeling object is created from the shape information for each part included in the three-dimensional data (CAD data, design data, etc., hereinafter referred to as 3D data) of the modeling object, Based on the weight information per unit volume of the modeling material mounted on the device and the created external shape information, the filling rate of the modeling material for each part is obtained, and each part is shaped according to the filling rate obtained for each part. The entire model is then made. In order to adjust the filling rate, for example, the honeycomb structure, sponge structure, and corrugated structure shown in FIG. In addition, as described above, the head shape can be devised so that air is entrained, the amount of entrained air can be adjusted, and cavities can be formed at a rate corresponding to the site.

  [Method for partially changing the weight per unit volume of a modeled object using a plurality of types of modeling materials (see FIGS. 1B and 1C)]

  In the case of this method, from the shape information of each part included in the 3D data of the modeling object, the external shape information of the modeling object is created, and the weight information per unit volume of the plurality of modeling materials mounted on the apparatus Based on the created outer shape information, a mixing ratio of a plurality of modeling materials for each part is determined, and the modeling materials mixed according to the determined mixing ratio are stacked to produce a modeled object. For example, when injecting a modeling material from a head, as shown to Fig.3 (a), you may adjust the mixing ratio of a some modeling material in a head according to a site | part (refer the left figure). A mixing unit for mixing the modeling material may be arranged in the front stage of the head, and the modeling material mixed by the mixing unit may be ejected from the head according to the part (see the right figure). Moreover, as shown in FIG.3 (b), each modeling material may be inject | poured into a separate head, a head may be switched for every site | part, and a desired modeling material may be inject | emitted (refer the left figure). A material selector for switching a plurality of modeling materials may be arranged in the front stage of the head, and the modeling material selected by the material selector may be ejected from the head according to the part (see the right figure).

  When comparing the case where the filling rate is changed using one type of modeling material and the case where the mixing ratio is changed using a plurality of types of modeling material, the former can be realized with a single material. One means is sufficient, and the structure can be simplified, but the upper limit of weight is limited to the state of modeling with a filling rate of 100%, and if the filling rate is lowered to make it lighter, the strength of the model can not be secured There is. On the other hand, the latter can increase the upper limit of weight by using a heavy modeling material, and the light portion can be modeled with a light modeling material, so that a decrease in strength can be prevented. A complex structure for mixing or selective injection is required. Thus, since each has a merit and a demerit, it is preferable to select suitably which one is employ | adopted according to the form of the molded article to produce.

  Next, a description will be given of an apparatus for producing a modeled object with the weight balance adjusted using the method shown in FIG. FIG. 4 is a block diagram illustrating the configuration of the three-dimensional object forming apparatus of the present embodiment. This three-dimensional object forming apparatus is an apparatus that forms a three-dimensional object using a melt deposition method (FDM), an ink jet method, or the like, and includes three blocks, a control block 10, a head moving mechanism block 20, and a modeling material handling block 30. Consists of Hereinafter, each block will be described.

[Control block]
The control block 10 includes a 3D data input unit 11, a weight balance calculation unit 12, a modeling parameter generation unit 13, a modeling material database 14, and the like.

  The 3D data input unit 11 acquires and analyzes 3D data in a file format standardized in the industry or a file format unique to each company from a computer device, transfers the external shape information to the modeling parameter generation unit 13, and The information that defines the information and the support conditions of the modeled object is transferred to the weight balance calculation unit 12. The method for acquiring 3D data is not particularly limited, and may be acquired using wired communication, wireless communication, short-range wireless communication such as Bluetooth (registered trademark), USB (Universal Serial Bus) memory, or the like. You may acquire using this recording medium. In addition, the 3D data may be acquired directly from a computer device that designs a modeling target, or may be acquired from a server that manages / stores 3D data.

  Based on the external shape information acquired from the 3D data input unit 11, the weight balance calculation unit 12 calculates the position of the center of gravity of the closed region (modeled object) surrounded by the 3D external shape and is surrounded by the 3D external shape. The relative weight of each part obtained by dividing the closed area is adjusted so that the weight balance can be achieved in the entire closed area. Then, information on the relative weight of each part after adjustment (referred to as weight distribution information) is transferred to the modeling parameter generation unit 13.

  The modeling parameter generation unit 13 is a unit volume or unit volume of one or more modeling materials acquired from the external shape information acquired from the 3D data input unit 11, the weight distribution information acquired from the weight balance calculation unit 12, and the modeling material database 14. The type, filling rate, and mixing ratio of the modeling material for each part are specified based on the per weight information, and the lamination method of the modeling material for each part is determined based on the information. Then, the mechanism control information for injecting the modeling material to a desired place is transmitted to the head moving mechanism block 20, and data for defining the modeling material for each layer is referred to as the modeling material handling block 30 (referred to as modeling slice data). .)

  The 3D data input unit 11, the weight balance calculation unit 12, and the modeling parameter generation unit 13 may be configured as hardware or function as the 3D data input unit 11, the weight balance calculation unit 12, and the modeling parameter generation unit 13. It is good also as a structure which comprises as a control program and operates the said control program with the apparatus which controls a solid object modeling apparatus or the said solid object modeling apparatus.

  The modeling material database 14 stores unit volume or weight information per unit volume of one or more modeling materials used for modeling, and provides the stored weight information to the modeling parameter generation unit 13. Note that the modeling material database 14 is not necessarily provided inside the three-dimensional object modeling apparatus, and may be provided outside the three-dimensional object modeling apparatus as long as the modeling parameter generation unit 13 can be referred to.

[Head moving mechanism block]
The head moving mechanism block 20 includes a head moving block 21 and a stage moving block 22. The head moving block 21 includes an X direction moving unit 21a and a Y direction moving unit 21b, and the stage moving block 22 includes a Z direction moving unit 22a.

  The head moving block 21 (the X direction moving unit 21a and the Y direction moving unit 21b) drives a motor and a driving mechanism (not shown) according to the mechanism control information acquired from the control block 10, and sets a head for injecting a modeling material to X. It can be freely moved in the direction (lateral direction) and the Y direction (lateral direction).

  The stage moving block 22 (Z direction moving unit 22a) drives a motor and a driving mechanism (not shown) according to the mechanism control information acquired from the control block 10, and moves the modeling stage in the Z direction (downward), or moves the head. The distance between the head and the modeled object is adjusted by moving the block 21 in the Z direction (upward).

[Building material handling block]
The modeling material handling block 30 includes a modeling material supply unit 31, a modeling material injection unit 32, a support material supply unit 33, a support material injection unit 34, and the like.

  The modeling material supply unit 31 selects a modeling material or mixes a plurality of modeling materials according to the modeling slice data acquired from the control block 10 and supplies the selected or mixed modeling material to the head. In addition, the modeling material injection unit 32 injects the modeling material onto the modeling stage in accordance with the modeling slice data acquired from the control block 10 and stacks it at a desired filling rate. In addition, the modeling material supply part 31 and the modeling material injection | emission part 32 may each be mounted in a three-dimensional object modeling apparatus, and may each be mounted in multiple numbers.

  The support material supply unit 33 supplies, to the head, a support material that is removed by water, heat, a release agent, or the like after the completion of modeling according to the modeling slice data acquired from the control block 10. Further, the support material injection unit 34 injects the support material onto the modeling stage according to the modeling slice data acquired from the control block 10 and stacks them. This support material plays a role like a pillar that supports the upper layer of the modeling material when modeling an overhanging part or the like when modeling in the upward direction. Therefore, when producing a modeled object that is not overhanging, the support material supply unit 33 and the support material injection unit 34 can be omitted.

  Next, a procedure for producing a modeled object with adjusted weight balance using the three-dimensional object modeled apparatus having the above configuration will be described with reference to the flowchart of FIG.

  First, 3D data such as CAD data and design data of a modeling target is created using a computer device.

  The 3D data created by the computer device is taken in by the control block 10 (3D data input unit 11) of the three-dimensional object modeling apparatus, and grasps the outer shape based on the 3D data. Then, the external shape information is sent to the modeling parameter generation unit 13 (S101). Further, the external shape information and information on the support conditions (support surface and support direction) embedded in the 3D data or designated by the user are sent to the weight balance calculation unit 12. Note that the above support conditions include, for example, a grounding surface, a support point, a support direction, and the like when a model is supported by a method such as “place”, “support”, “hang”, etc. It is.

  The weight balance calculation unit 12 adjusts the weight (unit volume or weight per volume) for each three-dimensional region without changing the three-dimensional outer shape of the modeling target (S102). For example, it is necessary to calculate the center of gravity when modeling the entire model with a uniform weight (the unit volume or the weight per unit volume is the same), or to change the center of gravity to the desired position. Calculate the weight distribution for each part of the object.

  More specifically, if the object to be modeled is intended for display, it is required to prevent it from tilting or overturning even if an earthquake or other external force is applied. In order to display in a well-balanced and stable manner, we do not create a model with a uniform weight (the weight per unit volume or volume is the same), but weigh each part (weight per unit volume or volume). It is desirable that the weight balance is adjusted by changing the center of gravity, and the center of gravity of the modeled object has a desired relationship with the ground contact surface. For example, in the case of a figurine supported by a surface, it is preferable that the vertical line of the center of gravity position coincides with or is close to the center of the ground contact surface. In addition, if it is supported from below by a point or supported by being suspended at a point, it is preferable that the vertical line of the center of gravity position of the modeled object coincides with or is close to the support point. Therefore, the weight balance calculation unit 12 does not set the entire modeled object to a uniform weight, but dares to change the weight of each part and obtains a weight balance at which the modeled object becomes stable.

  The modeling parameter generation unit 13 acquires weight information per unit volume of the modeling material to be used from the modeling material database 14 (S103). The shape of the modeling object is reproduced based on the external shape information obtained by analyzing the 3D data, the weight distribution information acquired from the weight balance calculation unit 12, and the weight information of the modeling material acquired from the modeling material database 14. And, in order to achieve the obtained weight balance, modeling information (mechanism control information for the head moving mechanism block 20; It converts into modeling slice data with respect to the modeling material handling block 30 (S104). And if conversion is completed, it will move to actual modeling operation | movement (S105).

  For example, if it is a three-dimensional object modeling apparatus that injects UV-cured resin from a modeling head and injects UV-curing resin and solidifies it by injecting and stacking modeling materials melted by heat, the injection position of the modeling material While moving in three dimensions, the molding material is injected and laminated at the same time. Also, if you want to model using one type of modeling material, UV curing resin stored in the tank is irradiated with ultraviolet laser to solidify and stack, powder modeling material stored in the tank is melted with laser, binder It can also be applied to a method of stacking while applying an adhesive called.

  As described above, in this embodiment, the external shape information, the support condition information, and the weight information per unit volume of the modeling material are used, and the weight balance of the modeled object is adjusted at the time of modeling. A modeled object whose lowering is unstable can be maintained in a stable state without tilting. In addition, as a method of making the model self-supporting, a method of changing the shape of the ground contact surface or adding a supporting member to make it self-contained can be considered, but in this example, the three-dimensional original shape is maintained, It is characterized by making it possible to create a model that is stable and independent. Hereinafter, a specific example will be described.

First, the case where a model of a tilted building as shown in FIG. If all the tilted cylindrical or columnar regions in FIG. 6B are modeled with a uniform weight (for example, the weight per volume is 5 g / cm ³ ), the center of gravity is located at the approximate center of the solid. Therefore, it is easy to fall down like the left figure. On the other hand, as shown in the right figure, the cylindrical or columnar shape is divided into regions at the positions indicated by broken lines, and the upper part is shaped with a small weight per volume (for example, 2 g / cm ³ ) and the lower part is per volume. If the weight is increased (for example, 7 g / cm ³ ), the position of the center of gravity approaches the center of the ground contact surface, so that it is difficult to fall down.

Here, the method of obtaining the center of gravity will be described. The object is composed of small molecules, and gravity acts on each molecule. The center of gravity is the point of action in which these gravitational forces concentrate on one point. In the three-dimensional object, the configuration can be divided into minute volumes to obtain the respective centroids, and the centroid of the entire object can be obtained by the resultant force. The center of gravity of each minute volume is the position of the intersection of diagonal lines as shown in FIG. Although the finely dividing the volume of the small region calculation accuracy of the center of gravity is improved, since the amount of calculation to finely increase or fixing the volume as 1 cm ^3, such as 100 divided in each direction of XYZ, the number It may be fixed.

  Further, the object having the shape as shown in FIG. 7B is divided into two parts A and B, and the centroids G1 and G2 are obtained by the intersections of the respective diagonal lines. Next, an arbitrary straight line G1-D is drawn from the center of gravity G1 of A, and a point C obtained by reversing the mass ratio on G1-D is obtained. Subsequently, a straight line CG parallel to D-G2 is drawn from the point C to obtain an intersection that intersects G1-G2. Thereby, the center of gravity G of objects having different shapes can be obtained.

  Next, a method for adjusting the center of gravity of the cylindrical shape or the columnar shape will be described. First, as shown in FIG. 8A, the center of gravity during uniform modeling is obtained. As described above, as described above, it can be obtained by subdividing the whole into a region of a minute volume and searching for a position where moments with respect to the center of gravity of all the minute regions are balanced.

  Next, as shown in FIG.8 (b), the surface (support surface) which can stand independently is specified. At that time, when the support surface has a shape having a vertex, a range surrounded by a broken line connecting the vertexes of the support surface is obtained. Then, it is determined whether or not the vertical line passing through the previously determined center of gravity passes through the region surrounding the support surface. It can be determined that it is independent when it passes through the area and is not independent when it does not pass. A method for designating the support surface will be described later.

  Next, as shown in FIG. 8C, when the modeled object does not stand on the support surface, the center of gravity position is moved by forming the model nonuniformly, and the vertical line of the center of gravity intersects the region surrounding the support surface. Change the weight balance as follows.

  Here, as a minimum condition for the modeled object having the support surface (ground surface) to stand on its own without falling down, as shown in FIG. 9, when the modeled object is installed with the support surface facing down, the center of gravity of the modeled object It is necessary that the line drawn from the position in the vertical direction intersects the inside of the surface surrounded by the line (broken line in the figure) connecting the outer periphery or the apex of the support surface.

  The operation of the three-dimensional object forming apparatus in this case will be described with reference to the flowchart of FIG. First, the weight balance calculation unit 12 obtains the position of the center of gravity when the entire 3D shape is made with a uniform weight (S201), specifies the support surface in the 3D shape, and obtains the region connecting the vertices of the support surface (S202). ). Next, the weight balance calculation unit 12 determines whether or not the vertical line of the center of gravity passes through the inside of the region surrounding the support surface (whether or not the model is independent from the positional relationship between the center of gravity position and the support surface) ( S203) When it is determined that it does not stand on its own, the weight distribution for each part of the model is changed, and the center of gravity is moved to the inside of the support surface (S204). Then, the modeling parameter generation unit 13 generates machine control information for controlling the head moving mechanism block 20 and modeling slice data for controlling the modeling material handling block 30, and models a modeled object with a desired weight balance (S205).

  In addition, as an optimum condition for a modeled object having a support surface (grounding surface) to be stable and independent, as shown in FIG. 11, when the modeled object is installed with the support surface facing down, the center of gravity of the modeled object It is important that the line drawn vertically from the position passes as close as possible to the mechanical center of the support surface (black circle in the figure).

  The operation of the three-dimensional object forming apparatus in this case will be described with reference to the flowchart of FIG. First, the weight balance calculation unit 12 obtains the position of the center of gravity when the entire 3D shape is made with a uniform weight (S301), specifies the support surface in the 3D shape, and obtains the mechanical center position of the support surface (S302). ). Next, the weight balance calculation unit 12 determines whether the vertical line of the center of gravity passes through the mechanical center position (whether the model is sufficiently stable and independent from the positional relationship between the center of gravity position and the mechanical center of the support surface). (S303), and if there is room for further stabilization by changing the position of the center of gravity, the weight distribution for each part of the model is changed so that the vertical line of the center of gravity approaches the mechanical center of the surface. (S304). And the modeling parameter production | generation part 13 produces | generates the modeling control data which controls the machine control information which controls the head moving mechanism block 20, and the modeling material handling block 30, and models a modeling thing by the weight balance which can be stabilized independently. (S305).

  As mentioned above, although the case where a modeling thing was made to stand on a support surface was demonstrated, as a method of displaying a modeling thing, there also exists the method of supporting with a point from the bottom, and the method of hanging. When supporting from the bottom on the support surface (grounding surface), the vertical direction of the support surface is the support direction, and the support direction can be determined uniquely, but when supporting or hanging at a point, information on the support direction is separately provided I need it. Therefore, in this embodiment, after clarifying the direction and position for supporting the modeled object, a modeled object having a suitable center of gravity with respect to the support direction and the support point is produced.

  FIG. 13 is an example of a model supported from below by one point. In this case, the case where the center of gravity of the modeled object is right above the support part or in the vertical direction is most stable, and the stress applied to the support part increases as the position of the center of gravity moves away from the position, so that the model easily falls. Therefore, the weight balance calculation unit 12 obtains a weight balance such that the center of gravity of the model matches or approaches a desired position that is stable at the time of display, so that a stable model can be modeled.

  FIG. 14 is an example of a model that is supported from below at a plurality of points. In this case, since the center of gravity of the modeled object is always one point, when there are a plurality of support parts, a virtual support part (usually an intermediate point between the two support parts) is considered in consideration of the resultant force of the plurality of support parts. And the weight balance calculation part 12 calculates | requires the weight balance that the gravity center of a molded article corresponds or approaches the vertical line which passes along a virtual support part, and makes it possible to model a stable molded article.

  FIG. 15 is an example of a model that is suspended and supported at one point. When hanging at a single point, specify the hanging position and the hanging direction (supporting direction against gravity). The reason for designating the support direction is that if the support direction is not designated, the form shown in the right figure may be obtained. In this case, the case where the center of gravity of the modeled object is directly below the suspended position or in the vertical direction is most stable, and the stress applied to the suspended position increases as the position of the center of gravity moves away from the position, and the tilt tends to occur. Therefore, the weight balance calculation unit 12 obtains a weight balance such that the center of gravity of the model matches or closes to the hanging position, so that a stable model can be modeled.

  FIG. 16 is an example of a model that is suspended and supported at a plurality of points. In the case of hanging at two points, the resultant force applied to the two support points is applied to the hook. When the model is placed in the desired orientation, the resultant force applied to the hook is the same as the vertical line passing through the hook, and the center of gravity of the model is most stable when the resultant or vertical line intersects the model. As the position of the center of gravity moves away from the position, the stress applied to the two support parts increases and the inclination tends to occur. Therefore, the weight balance calculation unit 12 obtains a weight balance such that the center of gravity of the model matches or approaches a desired position that is stable at the time of display, so that a stable model can be modeled.

  As described above, the case where the modeling object has a fixed shape has been described. However, one or more parts are movably connected to the modeling object, and a plurality of states are taken by moving one or more parts. There are also things to get. For example, when a robot or doll model as shown in FIG. 17 is formed, even if it is a pose that easily tilts forward, backward, left and right, the center of gravity is brought to the middle point to expand the range of self-supporting. In addition, as shown in FIG. 18, the center of gravity is brought to the middle point in a standing state, a lying state, or a standing state, so that a stable state can be maintained.

  In this case, the weight balance calculation unit 12 obtains an optimal center of gravity position in each movable state for a modeled object having a plurality of display shapes (modeled object having a movable part), The virtual center of gravity position (usually the midpoint) is obtained according to the calculated formula, and the weight distribution of each part is adjusted so that the obtained position becomes the center of gravity position. It becomes possible to form a modeled object that becomes a state.

  However, since the respective optimum center-of-gravity positions respectively obtained at the plurality of movable positions do not coincide with the intermediate positions obtained by the calculation, the stability with respect to each movable position is not the best. However, modeling to match the optimum center of gravity of one movable position improves that it is not self-supporting or extremely unstable in the display state at another movable position, and is relatively stable at multiple movable positions. It becomes possible to provide a model that is self-supporting.

  As described above, various methods for adjusting the weight balance have been described. However, as described above, in order to adjust the weight balance of a modeled object for display, it is necessary to specify a support surface (support part) and a support direction. is there. Below, the method of designating a support surface (support part) and a support direction is demonstrated concretely.

  As shown in FIG. 19A, there is a method of embedding an attribute indicating that the surface is a supporting surface with respect to a specific surface of the modeled object, as shown in FIG. For example, the support surface attribute is embedded in the bottom surface of the inclined cylinder. This method is a method of designating a specific surface by clicking the mouse cursor or touching the touch panel on the arrangement work screen of how to arrange the modeling object in the modeling area, which is performed before modeling. .

  In addition, as a method for specifying the support part and the support direction, as shown in FIG. 19B, at the time of creating the three-dimensional shape data, an attribute indicating that the part is a support part and support for the specific part of the modeled object. There is a method in which the direction information is embedded, and the indication direction information of the model is embedded in the file data. This method is performed before modeling, in the arrangement work screen of how to arrange the modeling object in the modeling area, specify a specific part by clicking the mouse cursor or touching the touch panel, etc. This is a method for designating the support holding direction by clicking the mouse cursor or drawing a direction line on the touch panel. Further, in this method, the support site can be designated by the origin-based spatial coordinate position in the modeling area, and the designated direction can be designated by the vector value from the origin.

  Even with the above-described designation method, there is no problem in the processing to realize a weight-balanced molded article, but a support surface and a support part, which are not necessary for a conventional 3D printer that does not consider the weight balance at the time of installation, Designation of the support direction is necessary in the control of this embodiment. Therefore, a method for simplifying this designation operation is proposed. That is, since the work itself of arranging a modeled object in a modeling area on a computer device before modeling is an action also performed by a conventional 3D printer, the instruction operation can be simplified by substituting this arrangement operation as a specified operation. Like that.

<Omitting method for designating support surface>
Specifically, in order to simplify the designation of the support surface, as shown in FIG. 19 (c), the surface facing the modeling stage surface is determined in advance to be the support surface of the modeled object. In this method, the support surface is uniquely determined simply by placing the modeled object in the same direction as the actual display direction in the work of arranging the modeled object in the modeling area on the computer device. Can do. Moreover, it can also determine beforehand that a specific surface (for example, side surface of a virtual stage) may be used as a support surface of a modeling object with respect to a modeling stage surface. In this method, the work surface is placed on the computer area on the computer device, and the support surface is uniquely determined simply by placing it in a direction laid 90 degrees with respect to the display direction of the finished work. Can do.

<Omitting method of designation of support direction>
In order to simplify the designation of the support direction, as shown in FIG. 19C, a direction perpendicular to the modeling stage surface is determined in advance as the support direction. In this method, the support direction is uniquely determined simply by arranging the modeled object in the same direction as the actual display direction in the operation of arranging the modeled object in the modeling area on the computer device. Can do. Further, it can be determined in advance so that a direction perpendicular to a specific surface (for example, a side surface of the virtual stage) with respect to the modeling stage surface is a support direction. In this method, the support direction is uniquely determined simply by placing the modeled object in the modeling area on the computer device and arranging it in the direction where the completed modeled object is laid 90 degrees with respect to the display direction. Can do.

  As described above, a self-supporting modeled object was created by adjusting the weight balance. However, since the modeled object is tilted as shown in FIG. 20A, the density and mixing ratio of the modeling material are limited to the limit. Even when the balance is adjusted every time and the position of the center of gravity is moved, the modeled object may not stand by itself or may not be sufficiently stable. In such a case, as shown in FIG. 20B, a support material for preventing the fall can be automatically added.

  Further, as shown in FIG. 21A, a suspended member can be added to the upper part of the center of gravity whose weight balance is adjusted, as shown in FIG. Alternatively, by marking the upper part of the center of gravity where the weight balance is adjusted, it is possible to easily know the optimum site for adding the suspension member. In addition, as shown in FIG. 21B, a fitting portion with the support base can be added to the lower part of the center of gravity whose weight balance is adjusted, as shown in FIG. Alternatively, by marking the lower part of the center of gravity where the weight balance is adjusted, it is possible to easily know the optimum site for adding the fitting portion with the support base.

  In addition, this invention is not limited to the said Example, The structure and control can be changed suitably, unless it deviates from the meaning of this invention.

  For example, in the above-described embodiment, the three-dimensional object forming apparatus using the melt deposition method (FDM) or the ink jet method is described, but for any method that can stack the forming material by adjusting the filling rate and the mixing ratio, The same can be applied.

  INDUSTRIAL APPLICABILITY The present invention can be used for a three-dimensional object modeling apparatus such as a 3D printer that models a three-dimensional object and a control program that operates on the apparatus.

DESCRIPTION OF SYMBOLS 10 Control block 11 3D data input part 12 Weight balance calculation part 13 Modeling parameter production | generation part 14 Modeling material database 20 Head movement mechanism block 21 Head movement block 21a X direction moving part 21b Y direction moving part 22 Stage moving block 22a Z direction moving part 30 modeling material handling block 31 modeling material supply unit 32 modeling material injection unit 33 support material supply unit 34 support material injection unit

Claims (20)

In a three-dimensional object modeling apparatus that forms a three-dimensional object by sequentially stacking modeling materials,
A data input unit for inputting three-dimensional shape information of the modeling object;
A modeling material database for storing weight information per unit volume of one or more modeling materials used for modeling;
Based on the shape information of the modeling object acquired from the data input unit, the center of gravity of the modeling object having the same shape as the modeling object is obtained, and the modeling object is in a stable state with respect to a specific support direction. , A weight balance calculation unit for calculating a weight distribution for each part of the modeled object,
Based on the shape information of the modeling object acquired from the data input unit, the weight distribution information calculated by the weight balance calculation unit, and the weight information of the one or more modeling materials acquired from the modeling material database. The modeling information for calculating the filling rate representing the degree of density of the modeling material or the mixing ratio of a plurality of modeling materials for each part of the modeling object and laminating the modeling material according to the calculated filling rate or mixing ratio A modeling parameter generation unit for generating
A modeling part that laminates the modeling material according to the modeling information;
A three-dimensional object shaping apparatus comprising: When making the modeled object self-supporting on a support surface designated in advance,
The model object is configured so that the weight balance calculation unit is arranged inside a region surrounded by a line connecting the outer periphery or the apex of the support surface, in which the center of gravity of the model object is extended in the vertical direction. The three-dimensional object shaping apparatus according to claim 1, wherein a weight distribution for each part is calculated.   The weight balance calculation unit calculates a weight distribution for each part of the modeled object so that a point obtained by extending the center of gravity of the modeled object in the vertical direction matches or approaches the center point of the support surface. The three-dimensional object shaping apparatus according to claim 2. When supporting the modeled object with one support site specified in advance,
The weight balance calculation unit calculates a weight distribution for each part of the modeled object so that a point obtained by extending the center of gravity of the modeled object in the vertical direction matches or approaches the support part. Item 3. A three-dimensional object shaping apparatus according to Item 1. When supporting the modeled object with a plurality of support parts specified in advance,
The weight balance calculation unit obtains one virtual support part from which the modeled object is stable with respect to the specific support direction from the plurality of support parts, and extends the center of gravity position of the modeled object in the vertical direction. The three-dimensional object modeling apparatus according to claim 1, wherein the weight distribution for each part of the modeled object is calculated so that the point matched or approaches the virtual support part. When making the modeled object having a movable part self-supporting on a support surface designated in advance,
The weight balance calculation unit obtains each center of gravity position when the movable unit is at a plurality of specific stop positions, obtains a specific center of gravity position from a plurality of center of gravity positions according to a predetermined calculation formula, and the shaped article The weight distribution for each part of the modeled object is arranged so that a point obtained by extending the specific gravity center position in the vertical direction is arranged inside a region surrounded by a line connecting the outer periphery or the apex of the support surface. The three-dimensional object forming apparatus according to claim 1, wherein the three-dimensional object forming device is calculated. When making the modeled object stand by a plurality of support surfaces specified in advance,
The weight balance calculation unit obtains each center of gravity position when the shaped object stands on each support surface, determines a specific center of gravity position from a plurality of center of gravity positions according to a predetermined calculation formula, Weight distribution for each part of the modeled object so that a point obtained by extending the specific gravity center position in the vertical direction is arranged inside an area surrounded by a line connecting the outer periphery or the apex of each supporting surface. The three-dimensional object shaping apparatus according to claim 1, wherein the three-dimensional object shaping apparatus is calculated.   The weight balance calculation unit calculates a weight distribution for each part of the modeled object so that a point obtained by extending the specific gravity center position of the modeled object in the vertical direction matches or approaches the center point of the support surface. The three-dimensional object modeling apparatus according to claim 6 or 7, When hanging the modeled object at one support point specified in advance,
The weight balance calculation unit calculates a weight distribution for each part of the modeled object so that a point obtained by extending the center of gravity of the modeled object in the vertical direction matches or approaches the support point. Item 3. A three-dimensional object shaping apparatus according to Item 1. When hanging the modeled object at a plurality of pre-designated support points,
The weight balance calculation unit obtains one virtual support point at which the model is stable with respect to the specific support direction from the plurality of support points, and extends the center of gravity position of the model in the vertical direction. The three-dimensional object modeling apparatus according to claim 1, wherein a weight distribution for each part of the modeled object is calculated so that the point that is made coincides with or approaches the virtual support point. A three-dimensional object modeling apparatus that models a three-dimensional object by sequentially stacking modeling materials, or a control program that operates on a control apparatus that controls the three-dimensional object modeling apparatus,
The three-dimensional object shaping apparatus or the control apparatus,
A data input unit for inputting three-dimensional shape information of the modeling object;
Based on the shape information of the modeling object acquired from the data input unit, the center of gravity of the modeling object having the same shape as the modeling object is obtained, and the modeling object is in a stable state with respect to a specific support direction. , A weight balance calculation unit for calculating a weight distribution for each part of the modeled object,
The shape information of the modeling object acquired from the data input unit, the weight distribution information calculated by the weight balance calculation unit, and the pre-stored per unit volume of one or more modeling materials used for modeling Based on the weight information, for each part of the modeled object, a filling rate representing the degree of density of the modeling material or a mixing ratio of a plurality of modeling materials is calculated, and the modeling material is determined according to the calculated packing rate or mixing ratio. A modeling parameter generation unit that generates modeling information for stacking,
A control program characterized by functioning as When making the modeled object self-supporting on a support surface designated in advance,
The model object is configured so that the weight balance calculation unit is arranged inside a region surrounded by a line connecting the outer periphery or the apex of the support surface, in which the center of gravity of the model object is extended in the vertical direction. The control program according to claim 11, wherein the weight distribution for each part is calculated.   The weight balance calculation unit calculates a weight distribution for each part of the modeled object so that a point obtained by extending the center of gravity of the modeled object in the vertical direction matches or approaches the center point of the support surface. The control program according to claim 12. When supporting the modeled object with one support site specified in advance,
The weight balance calculation unit calculates a weight distribution for each part of the modeled object so that a point obtained by extending the center of gravity of the modeled object in the vertical direction matches or approaches the support part. Item 12. The control program according to Item 11. When supporting the modeled object with a plurality of support parts specified in advance,
The weight balance calculation unit obtains one virtual support part from which the modeled object is stable with respect to the specific support direction from the plurality of support parts, and extends the center of gravity position of the modeled object in the vertical direction. The control program according to claim 11, wherein the weight distribution for each part of the modeled object is calculated so that the point that has been matched or approaches the virtual support part. When making the modeled object having a movable part self-supporting on a support surface designated in advance,
The weight balance calculation unit obtains each center of gravity position when the movable unit is at a plurality of specific stop positions, obtains a specific center of gravity position from a plurality of center of gravity positions according to a predetermined calculation formula, and the shaped article The weight distribution for each part of the modeled object is arranged so that a point obtained by extending the specific gravity center position in the vertical direction is arranged inside a region surrounded by a line connecting the outer periphery or the apex of the support surface. The control program according to claim 11, wherein the control program is calculated. When making the modeled object stand by a plurality of support surfaces specified in advance,
The weight balance calculation unit obtains each center of gravity position when the shaped object stands on each support surface, determines a specific center of gravity position from a plurality of center of gravity positions according to a predetermined calculation formula, Weight distribution for each part of the modeled object so that a point obtained by extending the specific gravity center position in the vertical direction is arranged inside an area surrounded by a line connecting the outer periphery or the apex of each supporting surface. The control program according to claim 11, wherein the control program is calculated.   The weight balance calculation unit calculates a weight distribution for each part of the modeled object so that a point obtained by extending the specific gravity center position of the modeled object in the vertical direction matches or approaches the center point of the support surface. The control program according to claim 16 or 17, wherein: When hanging the modeled object at one support point specified in advance,
The weight balance calculation unit calculates a weight distribution for each part of the modeled object so that a point obtained by extending the center of gravity of the modeled object in the vertical direction matches or approaches the support point. Item 12. The control program according to Item 11. When hanging the modeled object at a plurality of pre-designated support points,
The weight balance calculation unit obtains one virtual support point at which the model is stable with respect to the specific support direction from the plurality of support points, and extends the center of gravity position of the model in the vertical direction. The control program according to claim 11, wherein a weight distribution for each part of the modeled object is calculated so that a point that has been matched or approaches the virtual support point.

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