Week 02 - Computer-Aided Design
Goals
- Try several CAD softwares (2D and 3D)
- Create a 3D model of a part of the final project
Week's exploration and achievements
3D design softwares:
- I already had previous experience with Freecad and Tinkercad.
- This week I discovered two new softwares, Fusion 360 and Blender.
- I used Fusio 360 to create a model of a noh theater.
- I used Blender to create a rendering of that model. I only scratched the surface of that software which would require much more days of practice to be handled correctly.
- Overall I am really satisfied with Fusion 360, which combines great user interface, parametric design and efficiency. It seems it also has a lot of workbenches and features I haven't tested yet. Tinkercad is way too limited and I remember having some troubles navigating in Freecad's interface. As for Blender, it's not optimized for parametric design and technical parts. I'll thus probably mainly use Fusion 360 for the future weeks.
- [Edit]: I also tested to generate 3D models with code thanks to the software OpenSCAD during the week 3D scanning and printing, don't hesitate to have a look.
2D design softwares:
- I already had previous experience with the 2D vector design softwares Inkscape and Adobe InDesign.
- This week I used Inkscape to design a sign for our fablab. I then cut it with the lasercutting machine in various materials (plywood, bronze mirror acrylic and green acrylic) to create inlays.
- To make my design, I used a Path effect to create an interesting sun pattern, and other classic operations on paths.
- I don't really know about great alternatives to Inkscape, except Adobe InDesign, which is a very expensive software whereas Inkscape is open source and free. Inkscape is quite powerful and well documented, which makes it one of the most used software for 2D vector design in Fablabs. Also, I have experience in Inkscape. I'll thus carry on with Inkscape during Fabacademy.
- It's also possible to create 2D designs in Fusion 360 or other 3D design softwares, for example by exporting sketches in a .dxf format.
- [Edit]: I also experimented generating graphics with code thanks to the Javascript library p5.js during the Wildcard Week, don't hesitate to have a look.
3D Design in Fusion 360
As explained in the previous week, I have to think about a space structure for my light toolkit. A theater stage felt quite logical for such a 3D exploration. Nevertheless I wasn't too much appealed by occidental traditional theater stage, which are opened mainly on one side - the public's side. I had images of more oriental stages, with openings on many sides, wood based and quite cubic.
I looked for "japanese small theater" and found that noh theater stages looked a lot at what I was looking for! They have:
- the wood minimalistic aesthetic that I appreciate
- a lot of openings : the pillars exactly structure space without restraining it and invite to much modularity
- the shape allows to hide light elements in the floor
- the japanese aesthetic goes well with my idea of paper screens
Here are some images of noh theater that inspired me. The upper one is the largest noh theater in Japan, located in Nagoya (see the image source) and the second one is the Oshimah noh theater in Hiroshima (photo taken for the Nohgaku theater company by Sohta Kitazawa).
I was eager to learn how to use Fusion because it's a very widely known software in Fablabs, and it looks both powerful and accessible. I'm really not so good in 3D modeling yet and had recent experience only with Tinkercad and FreeCad (I used more professional softwares such as Catia during my engineering studies but that was years ago and I don't remember anything about them).
To create my noh stage inspired model, I looked at some pictures and plans of noh theaters. I will focus on the square main stage in the middle, and will not reproduce the gallery. If I go on with this idea, I may add the backstage behind the square main stage.
Here is the model I managed to create this week with Fusion 360:
Here is a short video showing the design process in Fusion 360:
Main stage base, vertical and horizontal pillars
I started drawing a sketch on the xy plane (Create menu). I draw a rectangle with one corner coincident to the origin of xy, then adjusted its dimensions (Create menu while drawing a sketch). For now I didn't create a dedicated parameter, I just set one side length to 314mm and the other to d1, which is the dimension of the first side. Since it is a rectangle it has parallel constraints, I then have a fully constrained shape. I click on Finish Sketch.
I then extruded the sketch towards the z-axis
I created an offset plane (Construct menu) on the top surface of my shape, with the offset left to zero.
On that offset plane, I created another sketch in which I draw a centered rectangle. I linked one side dimension to the other as I did with the first rectangle. I then extruded it, using the default operation join. Afterwards I created a shell that you can see in the following screenshots, but finally I removed this operation later on.
I created an offset plane on the top surface of my last extruded volume. I could then create a midplane (Construct menu) between the top plane and the xy bottom plane.
I then used the mirror feature (Create menu) to mirror my bottom extrusion relatively to the midplane created above.
Time to create the pillars of my stage! I created another offset plane on the newly created top surface, then created a sketch.
You can see on my screenshots that at first I tried to project some bottom shapes to that plan (projections in purple), but finally I went another way and didn't use these projections. I traced a centered rectangle and specified some dimensions. Again, I didn't use parameters yet but made sure that the x dimensions were linked to the y dimensions.
I then extruded it to make my first pillar.
I created a first midplane by selecting the front surface and the back surface of the taller extruded square. It's parallel to the yz plane.
Then, I created a second midplane by selecting the lateral surfaces. This midplane is parallel the xz plane.
I could now use the mirror operation to mirror my first pillar relatively to one of the midplane (I started with the one parallel to XZ). Then, I mirrored these two features (the two pillars) relatively to the second midplane.
I now have four pillars precisely linked one to another. I decided to try another the pillar height. I then had to go back in a previous feature, which is the extrusion corresponding to the first pillar and modify the distance of extrusion.
I could check that all pillars are correctly changing height at the same time. This is very convenient and I changed this height several time during my design process!
Then I created an offset plane on the intern surface of my parent pillar and create a sketch on it. The x and y axis allowed me to place a centered rectangle in the vertical middle of the pillar. I then linked the dimensions of my square in x and y.
Once my sketch validated, I could now extrude it and choose the extent type "to another object"
Then I created an axis through to planes (Construction menu) at the intersection of my two midplanes. This allowed me to create a circular pattern of my horizontal pillar, relatively to that axis. Note : I encountered a problem trying to do my circular pattern, I validated it but nothings happened. It worked when I changed the Compute Type 'Adjust' to 'Identical'. Not sure why though.
Here I have a good base for my stage!
Movable floor
I want to be able to place some light elements inside stage. A removable floor will then be placed on top. I can think of several options that can be used alternatively in my kit: * A transparent acrylic floor * A semi-transparent acrylic floor * An acrylic floor covered with a thin layer of wood, to be able to see the light through it * A wooden floor.
I then created a sketch on my floor's plane, draw and adjusted a rectangle, filleted the corners and extruded it with a cut operation, to create the space for my removable floor.
Next I had to create the space below to hide my light elements inside the stage. If you followed carefully you may have seen that at first I applied a shell operation to my stage. But finally I found it to confusing and hard to dimension correctly, so I removed that feature and created a completely new pocket inside my full stage. For this, I created a horizontal plane, then draw a rectangle in a sktech, added an horizontal offsetplane some millimeters above the original xy plance, anf finally extruded my rectangle with a cut operation and an extent to the offsetplane I just mentioned.
To complete my stage I needed to create a new body corresponding to my removable floor. I thus extruded my previous sketch (the one with the filleted corners) but this time with a New body operation. I rename this newly created body "Floor".
Roof structure
As it is very long to document each step individually as precisely as I did in the above, and also as I went back and forth in my design ideas, doing a lot of touch ups, I am only putting some screenshots. I mainly used the following operations :
- creating offsetplanes and midplanes
- creating sketches
- drawing rectangles / center-rectangles / other linear shapes
- adjust dimensions
- project geometries on a plane ('P' shortcut)
- coincident constraints
- collinear constraints
- horizontal/vertical constraints
- extrusion, mainly with the extent type 'to an object'
- mirror
- sweep
- pattern on path
Above: modification of the vertical pillars heigth.
Finally I went in Modify appearance and chose a default texture to apply to my objects (with a drag and drop). I used alternatively oak unfinished and bamboo semigloss for the wood.
Testing the light elements
I took the opportunity of having my 3D stage model to think about where I would place my light elements. I didn't think so much about their design yet but I think they will be quite slim, with a led strip inside.
For the light elements, I made three minimalistic designs, then tried to place one of them at different places of the stage. You can see on the images that I wanted to be able to put some of them under the roof, maybe with some magnets. They would thus be between the roof's slats. But afterwards I thought that it would be too bad not to place them in other directions. I'll maybe place a false ceiling, a bit like a created a fake floor.
Fancy roof and staircase
For fun I added a fancy roof and a small staircase. I used the following operations:
- Plane at angle
- Sweep
- Project on a plane
- Extrude (join, new body or cut)
- Mirror
- Fillet
For the staircase I used:
-
Offset plane
-
Midplane
-
Sketch lines
-
Extrude
I went to the render window to calculate an automatic rendering.
3D Rendering in Blender
I wanted to try the software Blender to render my model. I thus exported it from fusion in .stland imported it in Blender.
Unfortunately I didn't have much time to test it.
I only had the time to attempt applying some texture to my object. I thus downloaded some texture from polyhaven. I dowloade a plywood texture and a laminate wood.
First I selected my object then went to Material properties then added a material, renamed it and selected 'Image' as a Base color. I then imported one of my jpg / png file. You then need to select Display in preview material mode in the top right corner (Viewport Shading menu) of the 3d Viewport window (spheric icons).
I managed to do it with the default cube but not with the theater stage. Either in the 3D Viewport Window or the Shading menu I couldn't see the texture applied on my object. I resized the theater stage in case it was a dimension issue but that didn't seem to solve my problem.
After some research online, I went to the UV editing window, selected my object, then unwrapped it. It allowed me to apply my texture to the theater stage, even if it's far from good looking.
I hope I'll find some time to watch some basic tutorials about rendering in Blender in the next days!
2D Design
Inkscape
I already have some experience in Inkscape, so I didn't dig much more in the software for this week. I'm thus documenting a design which isn't related to my final project. This design was lasercut in wood and colored acrylics (bronze mirror and green) to create a part of a big sign for our Fablab.
This is the final design :
Here is the logo I want to customise. I first checked that the dimensions fit in my plank.
I wanted to design a sort of sun. I started with a simple straight line with two points, then add an effect on path, that is rotate copies. I played with the parameters to find something that I was satisfied with.
The black lines are the part of the Fablab Sorebonne-Université logo I want to customise. I placed my blue sun on the logo, then added a circle.
Since I'll have to manipulate the circle path, I transform the object into path wit Path > Object to Path. I do the same with the rays to be able to manipulate them independetly.
With the tool Select nodes, I added some nodes to the circle at the intersection of the circle and the rays (manually, after trying some path operation that didn't succed). I then used the operation delete a segment bewteen two nodes. I also used the operation cut according to path on the rays and the logo to remove exactly the part pointing out of the logo. Note that you need to separate the rays to do so (and duplicate the logo for each operation).
Once everything was neat, I duplicated the logo shape and changed the outline width for a much thicker one.
This is maybe not the cleaner way to make my closed shapes it bu it was very efficient: I painted the inside of my shapes with the paint bucket. That created new shapes.
Finally I could just keep these painted shapes, and add a fine red outline (I use red because that's how I'll tell the lasercutting machine that I want to cut these outlines). I also added a circle that I cut according to path.
I added some other floral shapes on the left part of the logo, thanks to the Bézier tool. That's it! Now I just have to cut the parts according to their fill colors (I used the filling colors only to visualize the result.)
I used a MDF board (3mm) as a base, then plywood (3mm), and acrylic infills in bronze mirror and green (3mm too). My colleague Stephane did the bottom with a CNC machine in thick plywood and thin aluminium.
