DUBINA 2021 by Anton Dubina - HTML preview

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Materialization visualization

The basis of the project activity is software. Design tools are programs that perform various functions. The creation of the DUBINA EVO vehicle information model began with a preliminary design. The sketch was created in the free bitmap graphics editor Krita. It is open source software included with KDE. Krita is developed primarily for artists and photographers and is distributed under the terms of the GNU GPL. The program supports non-destructive editing of layers and masks, work in various color spaces and with various color models — RGB, CMYK, LAB, in the mode from 8 to 32 bits with floating point per channel. In addition, popular filters (such as unsharp masking), adjustment layers, masks and dynamic filters, as well as a series of retouching tools are implemented. However, the main priority of the developers is the realization of opportunities for artists. The concept of the car, its overall dimensions and design features were presented in the draft design. After determining the main dimensions and design features, drawings of the future car were created.

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Krita program interface.

Drawings were made in the LibreCAD program. LibreCAD (formerly CADuntu) is a cross-platform, open and free CAD system for 2D drafting and design, built on the basis of QCad. LibreCAD allows you to solve problems of twodimensional design, such as the preparation of engineering and construction drawings, diagrams and plans. Works under Linux, Windows and Mac OS X operating systems. Distributed under the GNU General Public License version 2. The source code is written in the C ++ programming language using the Qt libraries. Further, a three-dimensional model was built using the drawings. The Blender program is optimal for 3D modeling. Blender is a comprehensive program that combines all the current 3D modeling capabilities. The program is not demanding on the characteristics of the computer, it is possible to carry out design planning, organize an assembly structure and prepare a model for printing on a 3D printer. The use of all basic types of modeling: free forms and sculpting, working with solids (including direct editing), the ability defining parametric dimensions, as well as support for obj and stl formats as imported geometry. All elements that are modeled can be used as further templates for work. The software supports various 3D file formats for import and export, including Alembic, 3D Studio (3DS), Filmbox (FBX), Autodesk (DXF), SVG, STL (for 3D printing), UDIM, USD, VRML, WebM

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LibreCAD program interface.

Three-dimensional models of car parts were assembled into assembly units and connected to the main parts of the car. The car body was built in sculpting mode. The construction was started by creating one polygon, which was split into 4 equal polygons. Adding one polygon after another gave the body shape. In places requiring more polygons, polygons have been subdivided by the required number. After constructing and editing the longitudinal half of the body, the symmetry modifier was applied. The modifier creates a symmetrical copy of the part. The resulting part changes its shape when the original part changes its shape. By connecting two symmetrical parts of the body, the result is a body when changing, the shape of which on one side changes the shape of the other side. To give the body smooth, smooth lines used three-dimensional patterns. A cylinder was used to build an even circumference of the wheel arches. By applying the cylinder to the wheel arch as a template, the polygon lines were aligned. To draw straight lines on the doors and the threshold of the case, rectangular planes were used. Three-dimensional patterns allow you to check the straightness of polygon lines from all sides. To visually determine the smoothness of the shape of the case, materials with a glossy surface are used. The visual determination of surface smoothness is influenced not only by the type of material, but also by the color.

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Blender program interface.

Details of mechanisms, gears of reducers were made in FreeCAD program. FreeCAD is an open source general purpose parametric CAD system (based on the LGPLv2 + license). The basis of geometric modeling of solids in FreeCAD is the principle of boundary representation, at the same time there is support for polygonal meshes. The geometric core of FreeCAD is OpenCASCADE. In addition to mechanical engineering tasks, FreeCAD can be used for tasks such as architectural design, or engineering analysis by the finite element method. Freecad supports over 30 file formats for importing. For the manufacture of car parts, 3D printing was used. 3D printing technology is universal. Part size for 3D printing is limited only by the size of the printer. A 3D printer is a peripheral device that uses the method of layer-by-layer creation of a three-dimensional object from a digital 3D model. No additional equipment is required for 3D printing. All types of parts are produced on one printer. In order to print a part on a 3D printer, you must first convert the original 3D model format into a G-code. G-code is a conditional naming of the programming language for numerically controlled devices (CNC). It was created by the Electronic Industries Alliance in the early 1960s. The Slic3r program is used to convert STL format to G-code format.

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FreeCAD program interface.

In this program, you can set the print speed, fill factor and more. After conversion, the file with the G-code is loaded into the 3D printer. Due to layer-bylayer shaping, parts of any complexity can be produced. Various materials are used for 3D printing. The most common PLA, ABS, PVA plastics, nylon, rubber, metal powder. The most productive 3D printing process is the stereolithography process. In the process of stereolithography, a layer of material is formed over the entire surface area simultaneously. The bright rays of light from the projector strike the clear glass. The glass is at the bottom of the bath with liquid lightcuring material. A projector under the glass transmits a cross-sectional image of each part of the part. Thus, the material on the glass hardens and is pulled layer by layer up from the bathroom.

The car is controlled by a program written in the Arduino IDE. It is a crossplatform application (for Windows, MacOS, Linux) developed in C and C ++. It is used to write and download programs to Arduino-compatible boards, as well as to boards from other manufacturers. Source code for The IDE is released under the GNU General Public License Version 2. The Arduino IDE supports both C and C ++ using special structuring rules. The Arduino IDE provides a software library from the Wiring project that provides many common input and output routines. User-written code only needs two basic functions to run the sketch and the main program loop, which are compiled and linked to the program stub main () to an executable loopback executor with the GNU toolchain, also included in the IDE distribution.

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Sparkmaker 3D printer and printed parts.