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Kanada, Y., International SFF Symposium 2013, August 2013.
[ 日本語のページ ]
[ Poster content + explanation ]
[ Updated poster PDF file ]
[ Poster photo ]

IMG_3034_edited-1.jpgAbstract: Usually, objects are horizontally sliced when printed by 3D printers. Therefore, if an object to be printed, such as a collection of fibers, originally have natural direction in shape, the printed direction contradicts with the natural direction. By using proper tools, such as field-oriented 3D paint software, field-oriented solid modelers, field-based slicing algorithms, and non-horizontal FDM 3D printers, the natural direction can be modeled and objects can be printed in a direction that is consistent with the natural direction. This consistence results in embodiment of momentum or force in expressions of the printed object. To achieve this goal, several manufacturing problems, but not all, have been solved. An application of this method is (Japanese) 3D calligraphy.

An online-journal version is available.

Introduction to this research theme: 3D shape formation technologies

Keywords: 3D printing, Three-dimensional printing, Solid Free-form Fabrication, SFF, Fused deposition modeling, FDM, Additive Manufacturing

Kanada, Y., 19th International Symposium on Artificial Life and Robotics (AROB 2014), 2014-1.
[ 日本語のページ ]
[ Paper (updated after the symposium) ]
[ Slides ]
[ Printing process (YouTube) ]

RIMG2281.jpgAbstract: 3D printing technology usually aims reproducing objects deterministically designed by 3D CAD tools. However, 3D printing can generate patterns similar to randomized (non-deterministic) 1D or 2D cellular automata (CA). Cheap fused deposition modeling (FDM) 3D printers can be used for this purpose. By using an FDM 3D printer, melted plastic filament is extruded by a hot nozzle to shape a 3D object. They can generate CA-like patterns with constant head motion and constant filament extrusion and with unintended fluctuation but no explicit randomness. Because of fluctuation, every time the printer generates a different emergent pattern. This paper proposes a method for printing seaweed-like patterns of 1D and 2D CA using FDM, and computational CA models. This method will open a new horizon of 3D printing applications.

Introduction to this research theme: 3D shape formation technologies

Keywords: 3D printing, Three-dimensional printing, Asynchronous cellular automata (CA), Randomness, Fluctuation, Solid Free-form Fabrication, SFF, Fused deposition modeling, FDM, Additive Manufacturing

Kanada, Y., 8th International Workshop on Natural Computing (IWNC 2014), 2014-3.
[ 日本語のページ ]
[ Slides ]
[ Book ]
[ Printing process (YouTube) ]

RIMG2281.jpgAbstract: Fused deposition modeling (FDM) is a 3D-printing method that shapes 3D objects by layering melted plastic filament. The process of this type of 3D printing can be regarded as asynchronous cellular-automata because it generates 1D on-off pattern per a head motion. Especially, by a constant head-motion at reduced constant extrusion-velocity, a 3D printer can generate self-organized grids or similar structures, which is much finer than artificial (i.e., program-controlled) patterns. Depending on the parameter values, i.e., layer depth, extrusion velocity, and so on, the generated pattern varies among regular stripes, stripes with crossing waves, and splitting and merging patterns. Some of the patterns can be simulated by a computational model, i.e., asynchronous cellular automata.

Introduction to this research theme: 3D shape formation technologies

Keywords: 3D printing, Asynchronous Cellular Automata, Randomness, Fluctuation, Solid Free-form Fabrication, SFF, Fused deposition modeling, FDM

Kanada, Y., BIT’s 1st Annual International Congress of 3D Printing, Dalian, China, June 27-29, 2014.
[ 日本語のページ ]
[ Slides w/o movies (PDF) (old ver) ]
[ Full-set slides (for Keynote, 65 MB) (old ver) ]
[ Printing process 1 (YouTube) ]
[ Printing process 2 (YouTube) ]

Abstract – Conventional 3D design methods design only the surface of 3D objects and conventional 3D printing methods only slice and print 3D objects horizontally. We in Dasyn.com develop new 3D design methods that enable designing real 3D objects including the internal structures and textures, and develop new 3D printing methods that enable printing patterns with non horizontal directions. The “real 3D design method” makes transparent objects and objects with holes much more realistic, and the non-horizontal 3D printing method enables naturally-directed objects such as 3D calligraphies. We also develops a naturally randomized or fluctuated 3D printing method. We seek partners who will develop applications of these methods.

RIMG2281.jpg 1011-04c.jpg

OlympicSymbol.jpg

Introduction to this research theme: 3D shape formation technologies

Keywords: 3D printing, Solid Free-form Fabrication, SFF, Fused deposition modeling, FDM, Transparent plastic

Kanada, Y., 20th International Workshop on Cellular Automata and Discrete Complex Systems (Automata 2014), July 2014.
[ 日本語のページ ]
[ Paper PDF file ]
[ Paper PDF file (extended ver. for IWNC8 book) ]
[ Slides (reduced size) ]
[ Slides (with a movie, Keynote) ]
[ Printing process (YouTube) ]

RIMG2281.jpgAbstract: 3D printers are usually used for printing objects designed by 3D CAD exactly, i.e., deterministically. However, 3D printing process contains stochastic self-organization process that generate emergent patterns. A method for generating fully self-organized patterns using a fused deposition modeling (FDM) 3D printer has been developed. Melted plastic filament is extruded constantly in this method; however, by using this method, various patterns, such as stripes, splitting and/or merging patterns, and meshes can be generated. A cellular-automata-based computational model that can simulate such patterns have also been developed.

Introduction to this research theme: 3D shape formation technologies

Keywords: 3D printing, Three-dimensional printing, Solid Free-form Fabrication, SFF, Fused deposition modeling, FDM, Additive Manufacturing, Asynchronous cellular automata, Randomness, Fluctuation

Kanada, Y., 2014 International Symposium on Flexible Automation (ISFA 2014), 2014-7.
[ 日本語のページ ]
[ Paper PDF file ]
[ Slides PDF file (w/o video) ]
[ Slides (Keynote file with video, for Macintosh) ]
[ Printing process 1 (YouTube) ]
[ Printing process 2 (YouTube) ]

Abstract: Although 3D objects to be printed may have “natural direction” or intended direction for printing, most 3D printing methods slice and print them horizontally. This causes staircase effect on the surface and prevents expression of the natural or intended direction; that is, the natural direction and the printing direction contradict. This paper proposes a methodology for direction-specified 3D printing and methods for designing, partitioning, and printing 3D objects with specified printing direction using a fused deposition modeling (FDM) printer. By using these methods, printed objects do not only have unnatural steps but also enables to express the direction explicitly. By developing and evaluating a set of methods based on this methodology, chained rings of an Olympic symbol are designed, partitioned, and printed by a delta-type 3D printer, which is cheaper but can move quick vertically. The rings were well designed and printed rings look well. Although there are still several unsolved problems including difficulty in deciding part partition points and weakness in the partition points, this methodology will probably enable new applications of 3D printing, such as 3D calligraphy.

Introduction to this research theme: 3D shape formation technologies

OlympicSymbol.jpg

Keywords: 3D printing, Solid Free-form Fabrication, SFF, Fused deposition modeling, FDM

Kanada, Y., IPSJ Summer Programming Symposium 2014 (in Japanese), 2014-8
[ 日本語のページ ]
[ Slides (Japanese PDF version, no movie) ]
[ Slides (Japanese Keynote version, with movie, for Macintosh) ]
[ Slides (English PDF version, no movie) ]
[ Slides (English Keynote version, with movie, for Macintosh) ]
[ Paper PDF file (in Japanese) ]
[ Printing process (YouTube) ]

[ “3D turtle graphics ” Python library and usage example ]

English version of this paper (IJERA)

skewedPyramid.jpgAbstract: When creating forms by using a 3D printer, usually, a static (declarative) model designed by using a 3D CAD system is translated and sent to the printer. However, widely-used FDM-type 3D printers inputs a dynamical (procedural) program that describes control of motions of the print head and extrusion of the filament. If the program is expressed by a programming language or a library in a straight manner, 3D objects can be created by a method similar to turtle graphics. Such a library, “turtle 3D printing” library, which is open-source, was described by Python and used (tried). Although this problem has a problem that it cannot print in the air; however, if this problem is solved by an appropriate method, shapes drawn by 3D turtle graphics can be embodied by this method.

Introduction to this research theme: 3D shape formation technologies

Keywords: 3D printing, Three-dimensional printing, Solid Free-form Fabrication, SFF, Fused deposition modeling, FDM, Additive Manufacturing, 3D turtle graphics, Turtle graphics

Kanada, Y., 4th International Conference on Additive Manufacturing and Bio-Manufacturing
(ICAM-BM 2014, Beijing)
, 2014-11.
[ 日本語のページ ]
[ Slides PDF file (w/o video) to be uploaded ]
[ Slides (Keynote file with video, for Macintosh) ]
[ Paper PDF file - not presented at the conference ]

[ "Generative art" shop (Japan only) ]

Abstract: Direction-specified 3D modeling and FDM-based printing methods enable expression of natural directions, such as hairs, fabric, or other directed textures, in modeled objects. This paper describes a method for creating various shapes of generative artistic objects with several specialized attributes by applying three new techniques to the direction-specified methods for better artistic expressions. The most important technique is “deformation”, which enables deforming simple 3D models to create varieties of shapes much more easily in generative design processes. The second technique is called the spiral/helical printing method, which enables consistent print-direction vector field, i.e., filament directions, of the surface consistent with those of the interior portion and enables seamless or less-seam printing results. The third technique controls light reflection while printing by using the spiral/helical printing method with transparent PLA. It enables the printed objects reflect light brilliantly. The proposed method with these three techniques was implemented as a Python library and evaluated by printing various shapes, and it is confirmed that this method works well and objects with attractive attributes can be created.

deformation-3dp.jpg

Introduction to this research theme: 3D shape formation technologies

Keywords: Fused deposition modeling, FDM, Direction-specified 3D printing, Direction-specified 3D modeling, Spiral/helical printing, Light reflection control, Generative art, Algorithmic design, Transparent plastic

Kanada, Y., Artificial Life and Robotics, Vol. 19, No. 4, pp. 311-316, November 2014, http://dx.doi.org/10.1007/s10015-014-0182-9
[ 日本語のページ ]
[ Springer's page (preprint) ]
[ Paper (draft) ]
[ Original paper (ISAROB 2014) ]
[ Printing process (YouTube) ]

RIMG2281.jpgAbstract: 3D printing technology usually aims at reproducing objects deterministically designed by 3D CAD tools; however, the author has discovered that 3D printing can also generate self-organizing patterns similar to stochastic (or randomized) 1D cellular automata (CA). A method for generating patterns similar to randomized 1D or 2D CA by using a fused deposition modeling 3D printer is thus proposed. With constant head motion and constant filament extrusion and without explicit randomness, this method generates very fine emergent patterns with natural fluctuation. By means of this method, each time a different pattern is generated. In addition, a computational CA model that simulates the above process is also proposed. The proposed method will open a new horizon of 3D printing applications.

Introduction to this research theme: 3D shape formation technologies

Keywords: 3D printing, self-organization, asynchronous cellular automata (CA), natural randomness, fluctuation, fused deposition modeling (FDM)

Kanada, Y., I/O 2015-4 (in Japanese).

[ 日本語のページ ]

Abstract: When printing a plate (dish) using a 3D printer, normally, so-called “support” material, which is disposed after printing, is required to be printed and to support the plate. However, try to create thin plates without using such superfluous material! Some devices are required to print them, but it is not so difficult.

IO201504dish1.jpg IO201504dish2.jpg

This article was revised and published as an English paper: 3D-Printing Plates without “Support”

Introduction to this research theme: 3D shape formation technologies

Keywords:

Kanada, Y., Int. Journal of Engineering Research and Applications (IJERA), Vol. 5, No 4, Part-5, April 2015, pp.70-77.
[ 日本語のページ ]
[ Paper PDF file (IJERA) ]
[ Paper PDF file (local) ]

この論文の日本語版 (IPSJ)

skewedPyramid.jpgAbstract: When creating shapes by using a 3D printer, usually, a static (declarative) model designed by using a 3D CAD system is translated to a CAM program and it is sent to the printer. However, widely-used FDM-type 3D printers input a dynamical (procedural) program that describes control of motions of the print head and extrusion of the filament. If the program is expressed by using a programming language or a library in a straight manner, solids can be created by a method similar to turtle graphics. An open-source library that enables “turtle 3D printing” method was described by Python and tested. Although this method currently has a problem that it cannot print in the air; however, if this problem is solved by an appropriate method, shapes drawn by 3D turtle graphics freely can be embodied by this method.

Introduction to this research theme: 3D shape formation technologies

Keywords: 3D printer, Turtle graphics, Fused Deposition Modeling, FDM

Kanada, Y., International Journal of Computer, Control, Quantum and Information Engineering, WASET, Vol. 9, No. 4, pp. 689-693, 2015.
[ 日本語のページ ]
[ Paper PDF file (Publisher site) ]
[ Paper PDF file (local site) ]

Abstract: Objects are usually horizontally sliced when printed by 3D printers. Therefore, if an object to be printed, such as a collection of fibers, originally has natural direction in shape, the printed direction contradicts with the natural direction. By using proper tools, such as field-oriented 3D paint software, field-oriented solid modelers, field-based tool-path generation software, and non-horizontal FDM 3D printers, the natural direction can be modeled and objects can be printed in a direction that is consistent with the natural direction. This consistence results in embodiment of momentum or force in expressions of the printed object. To achieve this goal, several design and manufacturing problems, but not all, have been solved. An application of this method is (Japanese) 3D calligraphy.

Note: This is the on-line journal version of a poster for SFF 2013

Introduction to this research theme: 3D shape formation technologies

Keywords: 3D printing, Three-dimensional printing, Solid free-form fabrication, SFF, Fused deposition modeling, FDM, Additive manufacturing

NaturalDesign3DP.jpg
Kanada, Y., I/O 2015-8 (in Japanese).

[ 日本語のページ ]

Abstract: 3D printers usually prints artificially-designed objects; however, certain unexpected patters are often generated. Let's enjoy such "naturally designed" patterns!

Introduction to this research theme: 3D shape formation technologies

Keywords:

Kanada, Y., International SFF Symposium 2015, August 2015.
[ 日本語のページ ]
[ Preliminary paper PDF file ]
[ Slide PDF file ]

1201-03-01-P1311432c.jpgAbstract: Material is stacked vertically and layer-by-layer in conventional additive manufacturing (AM) methods. An object with overhang or skewed stacking structure, such as a plain dish or an empty sphere, is difficult to be created by these methods without support material. This paper proposes a layer-less fused-deposition-modeling (FDM) method that enables mostly horizontal stacking of filament without support material. Such filament-stacking is enabled by increasing the height of the print head gradually, i.e., without layer transitions that make horizontal stacking difficult. The proposed method also allows controlling printing directions and various printing-direction-dependent expressions, such as fiber-like textures or brilliance, which make AM products attractive as final products for consumers or as some kinds of industrial products. Objects to be printed can be modeled as directed solid models designed by a component-based method (i.e., a new CAD based method) or a generative method, which are completely different from conventional CAD based methods.

Introduction to this research theme: 3D shape formation technologies

1011-04.jpg  1038-10.jpg 

Keywords:

Kanada, Y., International Journal of Computer, Control, Quantum and Information Engineering, WASET, Vol. 9, No. 5, pp. 568-574, 2015.
[ 日本語のページ ]
[ Paper PDF file (Publisher site) ]
[ Paper PDF file (local site) ]

Abstract: When printing a plate (or dish) by an FDM 3D printer, the process normally requires support material, which causes several problems. This paper proposes a method for forming thin plates without using wasteful support material. This method requires several extraordinary parameter values when slicing plates. The experiments show that the plates can, for the most part, be successfully formed using a conventional slicer and a 3D printer; however, seams between layers spoil them and the quality of printed objects strongly depends on the slicer.

Introduction to this research theme: 3D shape formation technologies

Keywords: Fused deposition modeling (FDM), 3D printing, Support-less, Layer seam, Slicer

Kanada, Y., 2015 JSME Annual Meeting, S044 Next Generation 3D Printing, 2015-9 (in Japanese).
[ 日本語のページ ]
[ Paper PDF file ]

Abstract: In 3D printing methods such as FDM, the direction of printing dominates the appearance and the nature of the printed objects. However, the direction cannot be specified in conventional 3D-printing methods. In this presentation, methods for designing and printing direction-specified 3D objects and the advantages of these methods are described.

Introduction to this research theme: 3D shape formation technologies

Keywords: Printing direction specification, Direction-specified design, Additive manufacturing, AM, Computer-aided design, CAD

Kanada, Y., 2015 JSME Annual Meeting, G120 General Session in Design Engineering and Systems, 2015-9 (in Japanese).
[ 日本語のページ ]
[ Paper PDF file ]

Abstract: As well as in computer programming, both declarative and procedural methods should be available in industrial product design. However, design for 3D printing is mostly based on declarative CAD as well as other areas of product design. This presentation reports a method for generative (procedural) design.

Introduction to this research theme: 3D shape formation technologies

Keywords: Declarative method, Procedural method, Generative design, Additive manufacturing, AM, Computer-aided design, CAD

Kanada, Y., 8th International Conference on Leading Edge Manufacturing in 21st Century (LEM 21), 2015-10.
[ 日本語のページ ]
[ Paper PDF file ]

1201-03-01-P1311432c.jpgAbstract: Instead of printing layer by layer, thin 3D objects can be printed in better quality (without seams between layers) by printing helically or spirally by fused deposition modeling (FDM). When printing helically or spirally, the amount of extruded filament can be modulated using a bitmap; that is, “zero” in bitmap means “thin” and “one” means “thick” (or vice versa). This process generates a thin object, such as a sphere, pod, or dish, with a bitmapped picture or characters. A typical example is a globe, which is printed using a bitmapped world map.

Introduction to this research theme: 3D shape formation technologies

Keywords: Computer-Aided Manufacturing (CAM), Additive manufacturing, Fused deposition modeling (FDM), Helical/spiral 3D printing, Bitmap, Texture

Kanada, Y., XIIIV Generative Art Conference (GA 2015), 2015-12.
[ 日本語のページ ]
[ Paper PDF file ]
[ Slides PDF file ]

Abstract: 3D models are usually designed by 3D modelling tools, which are not suited for generative art. This presentation proposes two methods for designing and printing generative 3D objects. First, by using a turtle-graphics-based method, the designer decides self-motion (self-centered motion) of a turtle and print a trajectory of the turtle as a 3D object (Fig. A). The trajectory is printed using a fused-deposition-modelling (FDM) 3D printer, which is the most popular type of 3D printer. Second, by using the assembly-and-deformation method, the designer assembles parts in a palette, each of which represents stacked filaments, applies deformations to the assembled model, and prints the resulting object by an FDM 3D printer. The designer can also map textures, characters, or pictures on the surface of the object. Various shapes can be generated by using the assembly-and-deformation method. If the initial model is a thin helix with a very low cylinder (i.e., an empty cylinder with a bottom), shapes like cups, dishes, or pods with attractive brilliance can be generated, and a globe and other shapes can be generated from a helix (Fig. B).

Introduction to this research theme: 3D shape formation technologies

GA2015-FigA.jpg

GA2015-FigB.jpg

Keywords: Design, Directed 3D printing, Fused deposition modelling (FDM)

Kanada, Y., in Y. Suzuki and M. Hagiya, ed., Recent Advances in Natural Computing, 2016.
[ 日本語のページ ]
[ Springer.com page ]
[ Amazon.co.jp page ]

Abstract:
3D printers are usually used for printing objects designed by 3D CAD exactly, i.e., deterministically.However, 3Dprinting process contains stochastic selforganization process that generate emergent patterns. A method for generating fully self-organized patterns using a fused depositionmodeling (FDM) 3D printer has been developed. Melted plastic filament is extruded constantly in this method; however, by using thismethod, various patterns, such as stripes, splitting and/or merging patterns, and meshes can be generated. A cellular-automata-based computational model that can simulate such patterns have also been developed.

Introduction to this research theme: 3D shape formation technologies

Keywords: 3D printing, Asynchronous cellular automata (CA), Randomness, Fluctuation, Fused deposition modeling (FDM)

Kanada, Y., IPSJ SIG on Programming, 2015 5th Meeting, 2016-2 (in Japanese).

[ 日本語のページ ]
[ Paper PDF file ]
[ Slides Keynote file (for Mac) with video ]
[ Slides PowerPoint file with video ]

Abstract: When manufacturing or 3D-printing a product using a computer, a program that procedurally controls manufacturing machines or 3D-printers is required. G-code is widely used for this purpose. G-code was developed for controlling of subtractive manufacturing, and a designer historically wrote programs in G-code; however, in recent development environments, the designer describes a declarative model by using CAD, and the computer converts it to a G-code program. However, because the process of additive man- ufacturing, such as 3D printing, is more intuitive than subtractive manufacturing, it sometimes seems to be advantageous to describe an abstract procedural program by the designer for this purpose. This paper, thus, proposes a method for generating G-code by describing an abstract Python program using a library for procedural 3D-design and for printing by a 3D printer, and shows use cases. Although shapes printable by this method are restricted, this method can eliminate layers and layer seams and eliminate support material, which is necessary for conventional methods when an overhang exists, and it enables seamless and artistic printing.

Introduction to this research theme: 3D shape formation technologies

Keywords: 3D printing, Additive manufacturing, Declarative model, Declarative description, Procedural description, 3D printer, G-code

Kanada, Y., Rapid Prototyping Journal, Vol. 22, No. 4, 2016.
[ 日本語のページ ]
[ Paper PDF file ]
[ Manuscript PDF file ]


Summarized abstract:

A methodology for designing and printing 3D objects with specified printing-direction using fused deposition modelling (FDM), which was proposed by a previous paper, enables the expression of natural directions, such as hairs, fabric, or other directed textures, in modelled objects. This paper aims to enhance this methodology for creating various shapes of generative visual objects with several specialized attributes.


The proposed enhancement consists of two new methods and a new technique. The first is a method for “deformation.” It enables deforming simple 3D models to create varieties of shapes much more easily in generative design processes. The second is the spiral/helical printing method. The print direction (filament direction) of each part of a printed object is made consistent by this method, and it also enables seamless printing results and enables low-angle overhang. The third, i.e., the light-reflection control technique, controls the properties of filament while printing with transparent PLA. It enables the printed objects to reflect light brilliantly.


...



Introduction to this research theme:
3D shape formation technologies


Structured abstract:

Purpose
A methodology for designing and printing 3D objects with specified printing-direction using fused deposition modelling (FDM), which was proposed by a previous paper, enables the expression of natural directions, such as hairs, fabric, or other directed textures, in modelled objects. This paper aims to enhance this methodology for creating various shapes of generative visual objects with several specialized attributes.
Design/methodology/approach
The proposed enhancement consists of two new methods and a new technique. The first is a method for “deformation.” It enables deforming simple 3D models to create varieties of shapes much more easily in generative design processes. The second is the spiral/helical printing method. The print direction (filament direction) of each part of a printed object is made consistent by this method, and it also enables seamless printing results and enables low-angle overhang. The third, i.e., the light-reflection control technique, controls the properties of filament while printing with transparent PLA. It enables the printed objects to reflect light brilliantly.
Findings
The proposed methods and technique were implemented in a Python library and evaluated by printing various shapes, and it is confirmed that they work well and objects with attractive attributes, such as the brilliance, can be created.
Research limitations/implications
The methods and technique proposed in this paper are not well-suited to industrial prototyping or manufacturing that require strength or intensity.
Practical implications
The techniques proposed in this paper are suited for generatively producing various a small number of products with artistic or visual properties.
Originality/value
This paper proposes a completely different methodology for 3D printing than the conventional CAD-based methodology and enables products that cannot be created by conventional methods.

Keywords:

Kanada, Y., IPSJ Transactions on Programming, Vol. 9, No. 4, pp. 1–9, 2016-9.

[ 日本語のページ ]
[ Paper PDF official version ]
[ Paper PDF file (prelimimary version) ]
[ Paper PDF file (Japanese version (refereed) -- not published) ]

Abstract: When manufacturing or 3D-printing a product using a computer, a program that procedurally controls manufacturing machines or 3D printers is required. G-code is widely used for this purpose. G-code was developed for controlling subtractive manufacturing (cutting work), and designers have historically written programs in G-code, but, in recently developed environments, the designer describes a declarative model by using computer-aided design (CAD), and the computer converts it to a G-code program. However, because the process of additive manufacturing, of which FDM-type 3D-printing is a prominent example, is more intuitive than subtractive manufacturing, it is some- times advantageous for the designer to describe an abstract procedural program for this purpose. This paper therefore proposes a method for generating G-code by describing a Python program using a library for procedural 3D design and for printing by a 3D printer, and it presents use cases. Although shapes printable by the method are restricted, this method can eliminate layers and layer seams as well as support, which is necessary for conventional methods when an overhang exists, and it enables seamless and aesthetic printing.

Introduction to this research theme: 3D shape formation technologies

Keywords: 3D printing, additive manufacturing, declarative model, declarative description, procedural description, 3D printer, G-code