Week 4 was all about conceptualising and perfecting our product idea. On Monday we decided to continue with the bike saddle and we ditched the chair seating and shoe sole ideas (but maybe in the future..?). In the picture shown below (which is of a chair seating instead of a saddle) you can see our thought process:
1. 2D pressure distribution
2. Belousov-Zhabotinsky reaction
3. 3D printed bicycle saddle
It starts with the identification of high and low pressure points on the saddle. A lot of research has been done in this field so we decided to use measurements from specialized researchers. The next step is to feed this information to the Belousov-Zhabotinsky reaction. We know from previous weeks that this can be achieved in different ways. Due to time pressure we are forced to use one of the less accurate methods which is controlling the starting point of the reactions by adding solution A in the right proportions. The final shape is then very dependent on nature’s random way of developing a pattern. Hopefully this week we can crack the method a bit more to come up with a shape that fits the pressure distribution well enough.
We film the reaction and create a stack of 2D images that represents the process over time. This information is fed to Avizo and we create a 3D model of the oscillating rings (where the height of the model is the passage of time). Once this has been done, we save it as an STL file and we move on to the next and final step. The pattern has to be measured and scaled to the real size and the the periphery of the saddle has to be cut out. One of the big problems is that Avizo turns the file into a mesh which is really difficult to work with in Rhino. Therefor we are now working with meshmixer software which makes this step a lot easier.
This week we also printed our first prototype made of two materials. The first thing we learned is the minimal thickness that the Connex3 can print. The blue part of the cilinder is the Belousov-Zhabotinsky reaction printed in hard material. The structure was lost because we scaled it too small. With this experiment we know all the scaling values we have to use for a proper pattern. The transparent part of the cilinder is flexibel material. We noticed that it bends really easily but there is not a lot of supsension when you push it in. We are going to research this further next week.