FA 2 - Computer Aided Design

Fab Academy 2

Computer Aided Design

INDEX:

Here you will find an Index with links to easily navigate through the section content.

1

Intro:

Description and reflections of this weeks learnings.

2

2D Design:

Here is an explanation of some basic concepts of Illustrator an vectorial image software.

3

2D Design Process:

Some basic explanation of how I used illustrator.

4

3D Design:

Description of the web tool I used for creating my website and how to connect it to my Git.

5

3D Design Process:

These are some basic concepts I learned of Rhino and used in the design of the first version of my project.

6

Reflections and Considerations:

Some final comments and learnings about this process.

1 - INTRO:

In this week we learned different possibilities to visualize our project using 2D and 3D design software, but one of the most interesting things was to see that there are a lot of softwares the we might have not used before that are Open Source and free tu use. Personally I am very used to the Adobe suit, and I'm more familiar with 3D software for animation like Cinema 4D and Maya, but another learning from this week was that even dough there are many different 2D and 3D softwares, you will find some easier than others for doing certain stuff.

2 - 2D Design:

2D stands for two dimensions, which basically means that your image will have a height and a width, but not a depth. It is basically how you see things when you close one eye. Anyway, with the use of lights, shadows and perspectives you can also simulate static 3D design using 2D software. In 2D design there are two basic types of images: Vectors and Bitmaps.

A Vector is a mathematical/geometrical approach to an image, in which you define certain shapes and give them some characteristics like filling colors and lines, and it has the advantage that it lets you scale these shapes as much as you want, to bigger or smaller scales, without loosing resolution of them, since the shape is always going to be the same, in different size, but filled with exactly the same color. (AI, SVG, PDF).

A Bitmap is an image generated by pixels that have different colors, and when you look those pixels from far, the mix of those images gives you the perception of colors and shadows. So, the more amount of pixels an image has to represent a certain area, the more resolution it will have. The problem with Bitmap images is that you could have pretty heavy files with them and also, that you will lose resolution if you star shrinking it or expanding it, because in those proceses it will loose pixels or generate new fake pixels to simulate the new size. (JPG, JPEG, PNG).

3 - 2D Design Software:

For the 2D design part, I used Adobe Illustrator, a paid vector software from the Adobe family, to create the logo of my project and a two dimensional visualization of what I imagine POWAR will look like.

For this, the first thing I did was to draw a sketch on a notebook using a pencil to imagine how the box will look, but trying to make it look tridimensional with the use of perspective. So the first thing I did was creating a new file on illustrator and imported the pencil sketch I did in the side, so I could compare it while I was designing the vector one. Then I aded some grids that would let me manage a similar perspective, and started creating the different objects separately, giving to each one a different color and some color characteristics like transparency to get some cool material effects. I also downloaded the plant from a free-vector page, and in the end added some lights to simulate how it will look like.

The process was basically creating shapes with lines, taking the grids in count, and then filling those shapes with colors and adding some transparencies.

POWAR AI FILE

4 - 3D Design:

3D stands for three dimensions, which means that the object you create will not only have height and width, but also will have depth, which is how our eyes see objects in real life because of the perception our eyes give to our brain when seeing something with two different points of view and mixing them.

When designing in 3D, each software has its own proprietary file format, and each industry has some favorite ones because of certain characteristics, but there are some neutral formats that are common between most 3D softwares and can hold different information like shapes o geometry, the materials or the appearance of the shape, lightning and other scene characteristics, and animations. I'm going to explain a bit about some of them, or at least the ones I used most during my FabAcademy, using an explanation I found in this article of All3DP.

STL:
STL (STereoLithography) is one of the most important neutral 3D file formats in the domain of 3D printing, rapid prototyping, and computer aided manufacturing. It generates a mesh which represents the geometry or shape of the object, but without any other characteristics like colors, appearance, lightning or animations. STL encodes the surface geometry of a 3D model approximately using a triangular mesh and it ignores appearance, scene, and animations. It is one of the simplest and leanest 3D file formats available today.

OBJ:
Is a format that includes the geometry mesh of the object but it can also store appearance related information, so it can be used in multi color 3D printing and others. The OBJ file format supports both approximate and precise encoding of surface geometry. When using the approximate encoding, it doesn’t restrict the surface mesh to triangular facets. If the user wants, he can use polygons like quadrilaterals. When using precise encoding, it uses smooth curves and surfaces such as NURBS. The OBJ format can encode color and texture information. This information is stored in a separate file with the extension .MTL (Material Template Library). It does not support any kind of animation. The format specifies both ASCII and binary encodings, but only the ASCII encoding is open source.

FBX:
FBX is a proprietary file format which is widely used in the film industry and video games. It supports geometry and appearance related properties like color and textures. It also supports skeletal animations and morphs. Both binary and ASCII files are supported. FBX is one of the most popular choices for animation. In addition, it is also used as an exchange format which facilitates high fidelity exchange between 3DS Max, Maya, MotionBuilder, Mudbox and other proprietary software.

COLLADA:
Collada is a neutral file format used heavily in the video game and film industry, and supports geometry, appearance related properties like color, material, textures, and animation. In addition, it is one of the rare formats supporting kinematics and physics. The COLLADA format stores data using the XML markup language.

3DS:
3DS is a proprietary file format used in architecture, engineering, education, and manufacturing. It retains only the most basic information about geometry, appearance, scene, and animation, and uses a triangular mesh to encode the surface geometry approximately, the total number of triangles being limited to 65536. It stores appearance related properties like color, texture, material, transmissivity etc. Scene information such camera position, lights can also be stored, but the format does not support directional light sources.

IGES:
IGES (pronounced eye-jess) is a neutral old timer used primarily in the defense industry and in the field of engineering. It was developed in the mid-seventies by the US Air Force. The IGES format is an ASCII encoding that is extremely flexible when it comes to representing surface geometry. It has the ability to use circuit diagrams, wireframes, precise free-form surfaces or CSG for storing geometry related information. The format can also store colors but does not support material properties like textures, material type etc. Animation is also not supported.

STEP:
STEP (The Standard for the Exchange for Product Data) or ISO 10303 was developed as a successor of the IGES file format. It is widely used in engineering related fields like automotive and aeronautic engineering, building construction etc. The corresponding file format is *.STP. The STEP format supports all the features supported by the IGES format. In addition, it can also encode topology, geometrical tolerances, material properties like textures, material types, and other complex product data.

5 - 3D Design Process:

To make the first modeling of my machine, I used the Rhino 3D 5.4 (MAC version) and began testing the technique of creating complete cubes and then extruding the interior, but then I realized that in order to later have the parts I would need ready to cut, it was better to create each of the parts separately and then join them.

That's why I started with the cube creation tool and with them I created what the sides of the box would be in acrylic sheets. For this I contemplated that the acrylic sheets would be 5mm thick. This structure is not a perfect 6-sided cube, since at the top it will carry the lighting and irrigation systems, which will come contained in a wooden box.

The Rhino tool of cubes, allows you to give them an initial point, then two secondary points that would be the points in X and Z, and at the end of the height, which would be the point Y. For this it is very important to keep in mind that the view is the indicated one, since this will affect how the commands work.

POWAR 3D FILE

ACRYLIC STRUCTURE:

(5mm thick acrylic panels)

- 1 Base (600mm x 600mm).
- 2 Lateral (600mm x 1200mm).
- 2 front and rear (590mm x 1200mm).

OBJECT SNAPS TOOL:

I repeated this process for each of the parts starting in point 0 and then with the OBJECT SNAPS TOOL and adjusted it to SNAP at the END and INTERSECTION of the pieces, and thus joined each corner with the corresponding corner of the other piece that should be connected.

* Using the top and front view, is a good way to see if everything is alligned, so it is important to be changing between views to check that everything is placed correct.

OBJECT MATERIALS:

By double-clicking the screen, you can open the OBJECT MATERIAL window, in which you can choose the colors for the materials and different options you want to apply to them like transparency, color, gloss, or even add a texture from a JPEG or PNG image.

To give a reinforcement to the bottom of the acrylic cube, which would contain the water used for irrigation and moisture, I propose to use 10mm thick boards, and I built the support in the same way as the acrylic water tank, but at the moment of I putting them together, I want to reverse the order of the lateral connection leftovers. Saying with this that, on the side that has the less wide sides of acrylic, will come the widest of wood sides, and vice versa.

WOOD PARTS:

LOWER BASE
(10mm thick wood panels):

- 1 Base (620mm x 620mm).
- 2 Laterales (600mm x 200mm).
- 2 frontales y traseros (620mm x 200mm).

UPPER TOP
(10mm thick wood panels):

- 1 Base (620mm x 620mm).
- 2 Laterales (600mm x 200mm).
- 2 frontales y traseros (620mm x 200mm).

The top and the bottom part are exactly the same, but what changes is the possition and orientation.

WATER FILTER:

LOWER BASE
(5mm thick acrylic panel):

- 1 Base (590mm x 590mm).

HOW IT WORKS? (how is it made)

It´s an acrylic panel with lazer cutted holes of 5mm, with a 30 mm separation between them for the water to pass by into the bottom tank.

For this I created the base acrylic panel, and then created an array of cilinders with the RECTANGULAR ARRAY TOOL in Rhino by added the settings I wanted and started trying with the different measures so that the array fits the size. Then I extruded the material from the panel.

WATERING SYSTEM:

WATER PIPES

This would be the system that pumps tha water from the tank up, and drain it again above the plant.

For this I created a cilinder, extruded it and also used the RECTANGULAR ARRAY TOOL.

6 - Reflections
and Considerations:

Personally, for 2D design I prefer to use Adobe Photoshop or Illustrator (depending if I'm working in vectors or bitmaps, something that I will explain later), but I discovered that Inkscape work pretty well to add some details to the schematics or to separate them before generating a file for the SRM. Inkscape also works pretty well for turning a raster or vector into a GCODE.

In the 3D softwares side, Cinema, Maya and others work pretty well for animations, while others like Rhino, Solid Works or Fusion 360, work better for product or architecture modeling. Also, in the case of Rhino, you can also use it with the Grasshopper tool, which lets you do amazing stuff going from parametric design, up to controlling a robot or CNC machine. Even dough, In my FabAcademy journey, I discovered that I like way more to use Fusion 360 because I find it more friendly than Rhino. I have not used yet Blender, but will give it a try in the future.

Here you can see some more Fusion 360 design videos y did during my FabAcademy journey.

Mobirise free maker - Check this