Paul Gröneveld @ Fab Academy 2016 >>> Computer-aided design

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The assignment for this week is: model a possible final project (raster, vector, 2D, 3D, render, animate, simulate, ...) ,and post it on your class page 2D, 2.5D design grid programs

Just to remind the reader of my site: I want to design a Robotic Beehive.

Photo from hand sketch

Below there is a photo from my iphone. I like to draw big on a flip over papaer. Cross sections makes thinks often much more clear compared to 3d sketching. This is a sideview cross section from the robotic bee hive. You see five drawer (axis Z12345). These can open with a screw spindle and a stepper motor. On the right you see an H-robot, with two motors. This system can take out a honeycomb frame and work with is. The honeycomb frame ac be connected to the front of a drawer. This way the dawer will be the z-axis for milling on a frame.


Sketchbook Xpress on tablet

What I like about Sketchbook express is that it is a 2d flexible hand sketch tool that you can use with a stylus-pen on your tablet. Very often it is for me useful to think about constructions and mechanisms not in 3d but in 2d, with side views and cross sections. Maximum 3 layers can be used and when you get used to it this is good enough. In the below animated gif, different sketchers of constructions are presented.


Animated video hand sketch

For generation ideas together with other people in a flexible way we use a project table in our department of the university. From different sources information can be projected on a screen made of glass. On top of this screen people can write and draw their thoughts and comments. Automatically the generated ideas are harvested, captured with a camera above the screen. After the meeting the information can be shared with the team for elaboration. In this case I use the screen with just a white background.

More information on the projecttable

The video below shows the first prototype of the Project table. Four different devices can be connected to the table for presenting information. All people who are joining the meeting can write and draw comments on the screen directly. It can be wiped off immediately because the information is captured with a camera above the screen. After a meeting the information is shared in a video.


After a video tutorial on Gimp, I can draw the conclusion that Gimp is a light version of Photoshop. The good thing about Gimp is that it is open source and free to use. Working with the layers is quite good until there are too many layers. Because I had too many I had to use too much time to sort it out. For this reason I show the incomplete drawing. The ruler function is great for the shapes that I need. My conclusion so far: nice software and easy to install.


Solidworks 2D sketch only

While using Gimp I was annoyed that it was not so parametric and precise adjustment were not easy to do. Still working in 2d can be very effective like I mentioned before. Thinking in 3d is more often complicated to understand. For this reason I started making parametric sketches in Solidworks. These sketches are side views from the robotic beehive. The sketches are animated in a gif to explain the movement from the different parts.



Inside a beehive there are many frames. These frames must be easy to take out from the hive. The problem here is that bee's like to glue all things together on the inside. Bee-keepers use a special tool to take out the frames. In the robotic beehive this can be don with a mechanism. In the sketch below the idea is drawn by hand. Later I tried to model it in Sketchup. My opinion about Sketchup: It is good to use for global ideas. When it has to be acurate it is more difficult to use. However I saw projects in Fablab Enschede where complex models were made in sketchup. Even for molded plastic parts. I need to learn more about it If I decide to use this program.






Onshape is like a combination from Google drive and Solidworks. Not all the features are available from Solidworks, but many shapes can be made. The user interface is quite different. They thought about the interaction very well is my first opinion. I know Solidworks well and I use google drive a lot. This is why I like Onshape! Down side is that you can only make 10 parts for free....


Solidworks 3d

Before I started modelling in Solidworks I first sketched the idea in Sketchbook Xpress. It is a bottle with a complex shape that will be cast in beeswax.


To elaborate further on this wax casting idea I used the project table with a white back ground. The bottle is sketched in 2d. The problem with the mold on the inside is that is not possible to take it out unless the core is separated in smaller parts. The smaller parts can be taken out from the inside through the hole in the centre. The outside of the bottle is also complicated to cast. When the cavity (outside mould) is separated in six parts, it is possible to take the casted part out of the mold. After the bottle the lid is sketched. The outside of the lid is comparable with the outside of the bottle. This time only three parts for the outside mould are needed. On the inside three hooks have an undercut for molding. To make casting possible “lifter” are needed. These are parts that slide in with an angle when opening the mold.

In the animation below screen dumps from Solidworks are shown from the bottle, the inside of the mold (core) and the outside of the mold (cavity).

The inside and outside of the bottle can be explored with the 3d stl-viewer below.


Honingpot- Combine1- Combine1 by fablacademypaul on Sketchfab

Files for sharing:

From Github: Beeswax honeypot plus 3d printed mold for casting.. Click "view raw" to download.

The beeswax honey pot plus 3d printable mold for casting can be downloaded here. It is a complex mold for the outside and inside.