JPH09180003A - Method and device for modeling three-dimensional shape - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily design a three-dimensional shape of high design property. SOLUTION: A designer 51 puts on a data glove 2 and a head mount display 3. A processor 1 displays an image 52 where a boxel aggregate 53 having boxels with unit volume arrayed in three dimensions and a cutting tool 56 are arranged in a three-dimensional modeling space on the head mount display 3 and moves the cutting tool 56 in the three-dimensional modeling space interlocking with the output signal of the data glove 2. The processor 1 detects a boxel 54 to be cut by the movement of the cutting tool 56 according to the position relation between each boxel in the boxel aggregate 53 and the cutting tool 56 in the three-dimensional modeling space and erases it to generate a free-form surface on the box aggregate 53.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to shape modeling, and more particularly to a method and apparatus for modeling the shape of a three-dimensional object having a free-form surface with high design.

[0002]

2. Description of the Related Art FIG. 8 shows a configuration example of a conventional three-dimensional shape modeling apparatus. In the figure, reference numeral 71 is a processing device provided with a CPU, memory and the like, and 72, 73, 74 and 75 are a keyboard, a mouse, a tablet (or digitizer) and a display device connected to the processing device 71. The input of the shape is performed by the designer using the keyboard 72, the mouse 73, and the tablet 74 to input parameters defining the shape such as dimensions, angles, and geometric coordinates to the processing device 71. In the processing device 71, various arithmetic processes are performed based on the numerical information input from the keyboard 72, the mouse 73, and the tablet 74 to model a three-dimensional shape, and the processed result is displayed on the display device 75 as a two-dimensional image. indicate.

Reference numeral 76 in FIG. 8 shows a display example of the display device 75. In this example, black circles such as P333 are three-dimensional geometric coordinate values and control points input by the operator using the keyboard 72, mouse 73, and tablet 74, and 77 is based on these three-dimensional geometric coordinate values and control points. The processing device 71 shows a free-form surface that is parametrically expressed by, for example, a Bezier interpolation formula. When a free-form surface is formed by the Bezier interpolation formula, it is necessary to give 12 control points to the four three-dimensional geometric coordinate values corresponding to the vertices.
For example, when a surface defined by four three-dimensional geometric coordinate values P333, P303, P003, P033 is formed into a free-form surface, two control points P233, P3 are provided for the vertex P333.
23, two control points P313, P for the vertex P303
203, two control points P103 for the vertex P003,
Two control points P02 for P013 and vertex P033
3 and P133, and four control points P1 in the plane
23, P113, P213, and P223 are given.

[0004]

Conventionally, a three-dimensional shape was modeled as described above. However, the number of control points designated for operating a free-form surface is large, and their three-dimensional coordinate values are calculated. Since it is necessary to input from the keyboard 72, the mouse 73, and the tablet 74, which are not suitable for inputting the three-dimensional shape, it is difficult to accurately specify the control points,
Moreover, the modeling work was complicated. Therefore, there is a problem in that it takes a long time to design a three-dimensional shape having a free-form curved surface having a particularly high design property, and nevertheless it is difficult to design the shape as the designer's image.

The present invention has been proposed in view of such circumstances, and an object thereof is to make it possible to easily design a three-dimensional shape with high designability.

[0006]

In order to achieve the above object, the present invention is based on the use of voxels to design the shape of a three-dimensional object. Here, the voxel is a virtual object having a predetermined shape (for example, a cube) having a unit volume. By using such voxels, it is possible to approximately construct an arbitrary shape by stacking a large number of voxels like blocks. However, in the method of stacking and forming a desired shape, there is a problem that the number of work steps increases, and conversely, by deleting unnecessary voxels from the previously stacked voxel collection, Design the shape. And erasing unnecessary voxels is
In order to facilitate the design of three-dimensional shapes with high design, it is possible to do it as if carving. That is,
A virtual cutting tool linked to the movement of the designer's hand is displayed in the three-dimensional shape modeling space together with the voxel aggregate,
The voxels to be cut are deleted from the voxel aggregate according to the movement of the cutting tool. Here, the virtual cutting tool may be in the shape of a human hand, or may be something like a spatula.

The three-dimensional shape modeling method of the present invention based on the above idea displays an image image in which a voxel aggregate in which voxels are three-dimensionally arranged and a cutting tool are arranged in a three-dimensional modeling space. The step of displaying the cutting tool on the apparatus and the output signal of the three-dimensional position input device for detecting the movement of the hand of the operator are interlocked with the cutting tool.
Moving in a three-dimensional modeling space, detecting a voxel to be cut by the movement of the cutting tool based on the positional relationship of the voxel and the cutting tool in the three-dimensional modeling space, and erasing the voxel And have.

A data glove or a touch glove, for example, is used as the three-dimensional position input device. A head mounted display is used as the display device, for example. Data gloves, touch gloves, and head mounted displays are devices that are widely used in the field of VR (Virtual Reality). By using such a device and moving the cutting tool in the three-dimensional modeling space in conjunction with the movement of the hand, the operator can feel as if he or she entered the three-dimensional modeling space.

The three-dimensional shape modeling apparatus of the present invention includes a memory for holding a voxel aggregate in which voxels are three-dimensionally arranged, a three-dimensional position input device for detecting movements of an operator's hand, and a display device. And a voxel data display control unit for displaying a collection of voxels held in the memory in the three-dimensional modeling space displayed in FIG. 6, and a cutting tool in the three-dimensional modeling space displayed on the display device. A cutting tool display control unit that moves the cutting tool in association with the output signal of the three-dimensional position input device, and movement of the cutting tool based on the positional relationship between the voxel and the cutting tool in the three-dimensional modeling space. A voxel data correction unit that detects a voxel to be cut by and deletes it from the memory.

In the three-dimensional shape modeling apparatus having such a configuration, the voxel data display control unit displays the collection of voxels held in the memory in the three-dimensional modeling space displayed on the display device. The cutting tool display control unit displays the cutting tool in the three-dimensional modeling space, the three-dimensional position input device detects the movement of the operator's hand, and the cutting tool display control unit detects the three-dimensional position input device. Moves the position of the cutting tool in conjunction with the output signal of. Then, the voxel data correction unit detects the voxel to be cut by the movement of the cutting tool based on the positional relationship of each voxel in the voxel aggregate and the cutting tool in the three-dimensional modeling space, and deletes it from the memory. .

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Next, an example of an embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a block diagram of a three-dimensional shape modeling apparatus according to an embodiment of the present invention. The three-dimensional shape modeling device of this example includes a processing device 1, a data glove 2, a head mounted display 3, and an operation unit 4. Although the data glove 2 is used as the three-dimensional position input device in this embodiment, a touch glove may be used. Although the head mounted display 3 is used as the display device, a normal display placed on a desk or the like may be used.

The data glove 2 is a device for detecting the movement of the hand of an operator (not shown), and the position information indicating the movement of the hand detected by the data glove 2 is the processing device 1.
Is transmitted to The head mounted display 3 is attached to the head of an operator (not shown), and provides the operator with an image image of the three-dimensional modeling space transmitted from the processing device 1. Also head mounted display 3
Transmits the viewpoint information of the operator to the processing device 1. The operation unit 4 is a device such as a keyboard, and is used when selecting a voxel aggregate to be processed or the like.

The processing device 1 is a device that controls the main processing of the three-dimensional shape modeling device, and includes a voxel data storage unit 11, a voxel data reading unit 12, and a work memory 1.
3, a voxel data display control unit 14, a cutting tool display control unit 15, a voxel data correction unit 16, and a voxel data writing unit 17 are provided as functional means. The processing device 1 is generally realized by a computer having a CPU, a main memory, and an auxiliary storage device.

The voxel data storage unit 11 is means for storing a voxel aggregate, and includes a basic component storage area 111 for storing one or more basic voxel aggregates, and a voxel aggregate that has been designed or is in the process of being designed. And a finished product storage area 112 for storing one or more of the following.

FIG. 2A is a schematic diagram of an example of a voxel aggregate stored in the basic component storage area 111 of the voxel data storage unit 11. Voxel aggregate 20 of this example
2 is a stack of cubic voxels 21 each having a unit length L on one side as shown in FIG. 2B, which are vertically m, horizontally n, and vertically 1. As a concrete data expression method of such a voxel aggregate 20, an expression method using an array such as B (m, n, l) can be used. Further, in the data of each voxel, as shown in FIG. 2C, a valid flag 22 indicating whether the voxel is valid and a voxel aggregate 20 are set in the three-dimensional modeling space as described later. In this case, the coordinate value 23 of the voxel in the three-dimensional modeling space in the three-dimensional modeling space is included. Here, as the coordinate value 23, in the case of the present embodiment, the coordinate value of the barycentric position 24 of the voxel 21 shown in FIG. 2B is used.

It is desirable that the basic unit 111 of the voxel data storage unit 11 stores in advance various voxel aggregates having an outer shape such as a rectangular parallelepiped, a cylinder, a torus, a sphere, and a cone. At this time, all the valid flags 22 shown in FIG. 2C of each voxel are validated.

Referring again to FIG. 1, the voxel data reading unit 12 is a means for inputting selection information of voxel data from the operation unit 4 and reading the corresponding voxel aggregate from the voxel data storage unit 11 into the work memory 13. is there. At this time, the voxel data reading unit 12 sets a specific coordinate value in the three-dimensional modeling space to the three-dimensional modeling space coordinate value 23 of each voxel forming the voxel aggregate shown in FIG. 2C. . For example, the barycentric position 24 of a specific voxel of a voxel aggregate is made to coincide with a specific coordinate value in the three-dimensional modeling space, and the coordinate value is set to 3 in FIG. 2 (c) of the specific voxel.
The three-dimensional modeling space coordinate values 23 are set, the three-dimensional modeling space coordinate values of the centroid positions 24 of the remaining voxels are sequentially calculated, and the three-dimensional modeling space coordinate values 23 are set.

The voxel data display control unit 14 periodically reads out the voxel aggregate stored in the work memory 13, and according to the three-dimensional modeling space coordinate value 23 of each voxel shown in FIG. Create an image of the outline of the head mount display 3
It is a means for transmitting to and displaying. At this time, the voxel data display control unit 14 controls the VR (Virtual Reality).
In consideration of the operator's viewpoint information transmitted from the head mounted display 3, as is often done in
Control is performed to display the outline of the voxel aggregate viewed from the operator's viewpoint.

The cutting tool display control unit 15 is means for controlling the display of the cutting tool in the three-dimensional modeling space. The cutting tool to be displayed may be a tool in the image of a spatula or the like, or the image itself of the operator's hand may be regarded as a cutting tool. Alternatively, a plurality of cutting tools may be prepared so that any tool can be selected by selection from the operation unit 4.

The cutting tool display control section 15 inputs the detection information of the movement of the operator's hand from the data glove 2, and moves the cutting tool in the three-dimensional modeling space so as to be linked to the movement. Display control. Also,
The current coordinate value of the cutting tool in the three-dimensional modeling space is transmitted to the voxel data correction unit 16. Here, as the coordinate value to be transmitted, the coordinate value of each vertex of the outer shape of the cutting tool is used in this embodiment. Therefore, when using a cutting tool having a rectangular parallelepiped shape, the coordinate values of a total of eight vertices are transmitted to the voxel data correction unit 16.

The voxel data correction unit 16 calculates the coordinate value of each voxel in the voxel aggregate stored in the work memory 13 in the three-dimensional modeling space and the cutting tool's 3 values.
It is a means for detecting a voxel to be cut by the movement of the cutting tool based on the coordinate value in the dimensional modeling space and deleting it from the work memory 13. Here, the voxel is deleted by turning off the valid flag shown in FIG. 2C in this embodiment.

The voxel data writing unit 17 is a means for reading a voxel aggregate whose design has been completed or is in the process of being designed from the work memory 13 and stores it in the finished product storage area 112 of the voxel data storage unit 11.

FIG. 3 is a flowchart showing a processing example of the processing apparatus 1. First, the operator inputs the selection information of the voxel aggregate to the processing device 1 from the operation unit 4. As described above, since the voxel aggregate having various outer shapes is stored in the basic component storage area 111 of the voxel data storage unit 11, it is preferable to select the one having a final three-dimensional shape. Of course, it is also possible to select the voxel aggregate stored in the finished product storage area 112. The voxel data reading unit 12 of the processing device 1 inputs the selection information from the operation unit 4 to read the corresponding voxel aggregate from the voxel data storage unit 11, and for each voxel of the voxel aggregate, see FIG. The three-dimensional modeling space coordinate value 23 shown in c) is set and stored in the work memory 13 (S
1). When the voxel aggregate is stored in the work memory 13, the voxel data display control unit 14 starts display control, and the three-dimensional modeling space coordinate value 23 and the valid flag in each voxel of the voxel aggregate stored in the work memory 13 and the valid flag. According to 22, the image image of the outer shape of the object constituted only by the voxels for which the valid flag 22 is turned on is displayed on the head mounted display 3 (S2). This allows the head mounted display 3
The operator wearing the can recognize the outer shape of the object to be processed.

Next, when the operator wears the data glove 2 and instructs the processing device 1 to perform the calibration from the operation part 4, the cutting tool display control part 15 three-dimensionally models the position information generated by the data glove 2. In order to map to the space, the origin position of the cutting tool, the scale, etc. are calibrated (S3), and the image of the cutting tool is displayed on the head mounted display 3 (S).
4).

After that, the operator moves the hand wearing the data glove 2 to process the outer shape of the voxel aggregate with a cutting tool (S5). In this cutting processing S5, the cutting tool display control unit 15 moves the cutting tool displayed on the head mount display 3 in the three-dimensional modeling space according to the position information from the data globe 2, and at each time. The coordinate values of the cutting tool in the three-dimensional modeling space are transmitted to the voxel data correction unit 16.
In the voxel data correction unit 16, based on the coordinate values of each voxel in the voxel aggregate stored in the work memory 13 in the three-dimensional modeling space and the coordinate values of the cutting tool in the three-dimensional modeling space, The voxel to be cut by the movement of the cutting tool is detected, and the detected voxel is erased. That is, the valid flag 22 of FIG.
Turn off.

Various methods are conceivable as a method for determining the voxels to be erased. In the present embodiment, for example, as shown in FIG. 4, in the voxel data correction unit 16, the three-dimensional area in the three-dimensional modeling space occupied by the cutting tool according to the coordinate values of the cutting tool notified from the cutting tool display control unit 15. Process S11 for obtaining P every moment and the area P
A process S1 of searching the work memory 13 for voxels in which the three-dimensional modeling space coordinate values 23 are included and deleting the voxels.
The method of repeating 2 and 2 is used.

The operator repeats the above-described processing operations to form the voxel aggregate into a final shape. When the end instruction is input to the processing device 1 from the operation unit 4, the voxel data writing unit 17 causes the work memory 13 to operate.
The voxel aggregate stored in is stored in the finished product storage area 112 of the voxel data storage unit 11 (S6). The valid flag 22 of the voxel aggregate thus saved
The modeling result is an aggregate consisting only of voxels for which is turned on.

FIG. 5 is a schematic view of a situation where the operator is performing a modeling work of a three-dimensional shape. The operator 51 wears the data glove 2 and the head mount display 3, and the data glove 2 detects the movement of the hand of the operator 51 and sends the position information to the processing device 1. The head mounted display 3 also sends position information as viewpoint information to the processing device 1. The processing device 1 causes the voxel aggregate and the cutting tool to move to 3 by the operation as described above.
An image image arranged in the dimensional modeling space is displayed on the head mounted display 3 as indicated by reference numeral 52 in the figure. In this image 52, 53 is a voxel aggregate, 54 is one voxel thereof, 55 is a character reflecting the position of the operator's hand as a position in the three-dimensional modeling space, and 56 is a character of a cutting tool. Shown respectively. Reference numeral 58 is a locus of movement of the cutting tool 56 in the three-dimensional modeling space as the operator 51 moves the hand wearing the data glove 2 (this locus itself is not displayed). Then, 57 is a boundary surface newly generated as a result of voxel erasing by the voxel data correction unit 16 with the movement of the cutting tool 56, which is a free-form surface generated by the operator 51.

In the above embodiments, the array is used as the data structure for expressing the voxel aggregate, but it may be expressed by the list structure. For example, when the voxel is a cube, there can be adjacent voxels for each of its six faces, so that the data of each voxel has six bidirectional pointers 61 to 66 as shown in FIG. If it exists, the data address of the adjacent voxel is set. 67 is a three-dimensional modeling space coordinate value used in the same manner as the three-dimensional modeling space coordinate value 23 of FIG. When the list structure is used, the valid flag shown in FIG. 2C is not used, the data of the voxel is erased, and the bidirectional pointer of the voxel adjacent to the voxel is changed to the NULL value.

Further, in the above embodiment, the voxel data storage unit 11 stores a voxel aggregate having a basic outer shape such as a cube and a rectangular parallelepiped and a voxel aggregate already designed, and uses them to create a new one. Modeled the outer shape. However, a voxel aggregate is generated from the measurement data obtained by measuring the actual size and shape of the product with a three-dimensional measuring machine or a CT scan device, and the generated voxel aggregate is stored in the voxel data storage unit 11. It may be used for design. Also, a combination of a plurality of voxel aggregates corresponding to the actual product thus generated may be stored as a new voxel aggregate.

FIG. 7 shows the combination of two voxel aggregates into one.
An example of a method of generating one voxel aggregate is shown. First, as shown in FIG. 3A, one voxel aggregate 61 generated from the data of the point group whose dimension and shape of the product is measured by a three-dimensional measuring machine, and another voxel aggregate generated in the same manner. The body 62 is taken into the three-dimensional modeling space 63 and displayed on the head mounted display. Next, as shown in FIG. 6B, the voxel aggregate 62 is grasped by the character 64 of the data glove and released at a desired position in contact with the voxel aggregate 61. At this time, the three-dimensional modeling space coordinate value of each voxel that constitutes the voxel aggregate 62 is corrected according to the movement. Then, when the voxel aggregate 65 in which the voxel aggregate 61 and the voxel aggregate 62 are combined is stored, the three-dimensional modeling space coordinate value of each voxel is examined, and the voxel aggregate 61 and the voxel aggregate 62 are adjacent to each other. The addresses of the other voxels are set in the bidirectional pointers 61 to 66 shown in FIG. 6 of the partial voxels. As a result, the voxel aggregate 6 of the sum of the voxel aggregate 61 and the voxel aggregate 62
5 can be obtained.

[0033]

As described above, according to the present invention,
A voxel assembly placed in a 3D modeling space can be modeled into a 3D shape by freely processing it as if engraving with a cutting tool that works in conjunction with hand movements. It is possible to easily design a three-dimensional shape having a free-form surface with high designability that cannot be represented by the image of the designer.

[Brief description of the drawings]

FIG. 1 is a block diagram of one embodiment of the present invention.

FIG. 2 is an explanatory diagram of a voxel aggregate, voxels, and voxel data.

FIG. 3 is a flowchart showing a processing example of an embodiment of the present invention.

FIG. 4 is a flowchart showing an example of a method for detecting voxels to be cut by a cutting tool.

FIG. 5 is a schematic view of a situation where an operator is performing modeling work of a three-dimensional shape.

FIG. 6 is a diagram showing another example of a data structure expressing a voxel aggregate.

FIG. 7 is an explanatory diagram of a method of combining two voxel aggregates to generate one voxel aggregate.

FIG. 8 is an explanatory diagram of a conventional three-dimensional shape modeling device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Processor 11 ... Voxel data storage part 111 ... Basic part storage area 112 ... Finished product storage area 12 ... Voxel data reading part 13 ... Work memory 14 ... Voxel data display control part 15 ... Cutting tool display control part 16 ... Voxel data Modifying unit 17 ... Voxel data writing unit 2 ... Data glove 3 ... Head mounted display 4 ... Operation unit

Claims (6)

[Claims] 1. Using a voxel having a unit volume of 3
A three-dimensional shape modeling method for designing the shape of a three-dimensional object, wherein an image image in which a voxel aggregate in which voxels are three-dimensionally arranged and a cutting tool are arranged in a three-dimensional modeling space is displayed on a display device. A step of moving the cutting tool in the three-dimensional modeling space in conjunction with an output signal of a three-dimensional position input device that detects a movement of an operator's hand; and the voxel and the three-dimensional shape of the cutting tool. Detecting a voxel to be cut by the movement of the cutting tool based on a positional relationship in a modeling space, and erasing the voxel, the three-dimensional shape modeling method. 2. The three-dimensional shape modeling method according to claim 1, wherein a data glove or a touch glove is used as the three-dimensional position input device. 3. The three-dimensional shape modeling method according to claim 2, wherein a head mounted display is used as the display device. 4. Using voxels having a unit volume, 3
A three-dimensional shape modeling device for designing the shape of a three-dimensional object, comprising: a memory that holds a voxel aggregate in which voxels are three-dimensionally arranged; a three-dimensional position input device that detects movement of an operator's hand; A voxel data display control unit that displays a collection of voxels held in the memory in the three-dimensional modeling space displayed on the device, and a cutting tool in the three-dimensional modeling space displayed on the display device, A cutting tool display control unit that moves the cutting tool in association with an output signal of the three-dimensional position input device, and a positional relationship of the cutting tool based on a positional relationship between the voxel and the cutting tool in the three-dimensional modeling space. A voxel data correction unit that detects a voxel to be cut by movement and deletes it from the memory. 3-dimensional shape modeling apparatus that. 5. The three-dimensional shape modeling apparatus according to claim 4, wherein a data glove or a touch glove is used as the three-dimensional position input device. 6. The three-dimensional shape modeling device according to claim 5, wherein a head mounted display is used as the display device.