This is the final week of our project and we still have quite some things to do before we are ready for the science fair. Only half way through the project we discovered and really understood all the possiblities of using reaction diffusion in 3D printing. Since we are almost done, our goal is to lead the way for our successors and to also create some visual and scientific material about reaction diffusion in 3D printing to present next Tuesday.
Last week we created a lot of video material of the Belousov-Zhabotinsky reaction. One reaction showed really nice symmetrical spirals that also corresponds with the wanted pressure distribution of the saddle. We decided to use this pattern for our final 3D print. It is shown on the right.
Max has been working with Rhino and Meshmixer for the last two weeks and he created a nice saddle shape which we use to cut out the Avizo files. It is a standard racer bike model but we adapted the upside so that if someone sits on the saddle and the cones are pushed down, the surface will be approximitely flat. We printed a small sample of the saddle to get a better understanding of our final product (shown on the right). The blue parts are solid and the transparent parts are flexibel. We are really happy with this first print but there are two problems we noticed:
– the model can break easily if two solid parts are connected by only flexibel material
– there is no suspension if the hard material from different cones is not seperated completely by flexibel material.
Our first conclusion is that we need a plate underneath the 3D print to support the weaker parts of the saddle. We spend Tuesday morning building this part and added a construction that can fix the saddle onto a bicycle. We want to solve the second problem by magnifying the spiral patterns so that the width of the cones is always big enough to seperate the layers.
We printed a second test model of a sphere. It contains the spiral pattern which we talked about earlier, only this time enlarged. We started testing it and we noticed that there again is very little suspension. This is due to the fact that the hard spiral structure consists of one piece which cannot bend. We want to have a functioning saddle next week so we decided to test some different structures/materials to see if anything works better than our current model. The findings can be found in the research folder.
The rest of our work this week consisted of creating visual material for the science fair and a lot of hours in Rhino and Meshmixer.