MECHANICAL DESIGN

Goals:
Do the mechanical design for your final project

At the lab
My final project doesn't have an specific and big mechanical design so I was thinking about doing a couple of things that are mechanical: a handlebar for my final project and pan tilt that will move the case of my final project as well.
With this handlebar I can fix the case of my final project in the mast or the boom of the boat. And with the pan tilt I will mesure the movements of the case, once this is made.

The handlebar
One of the goals of my final project will be fixing a case inside of a boat, so I was planing to fix the case in the same mast of the boat. One accelerometer will mesure movement parameters constantly. To do this I was thinking in a PLA mount that with the help of some screws will fix my case to the mast.

Designing
I design the object in Inventor. Inventor is a powerfull 3D designing tool. You will have to get used to it because is not specially intuitive but once you manage it it'd very easy and confortable to use and change the parameters. So firstly I design an object that could work for my case, which is going to be a dodecahedron. I print the first prototype with the Ultimaker 2 and see how it is:

It is a bit weak and maybe it's too long for what I need so I design another object very similar but with less high. Also the material suport was impossible to remove:



After some pre-designs these two are the objetcs that I create to fix the case. The mechanical solution is:
- Screws of 6mm x 3
- PLA material

It moves some degrees in order to position the case wherever is more suitable. I made some tests on the field and it works pretty decent







Once it is made it's time to test in on the mast of the sailing boats:



The Pantilt
I also made a Pan tilt. With this mechanical object I could support the case of my final project on it and mesure the movements that this is making with the accelerometer.

For that purpose I design a regular PLA pantilt; it's a bit modified version of the regular one but it also works with two stepper motors. I print the parts of the object with the Ultimaker 2 and the result is the expected.

I forgot to draw some holes in some pieces of the .stl object so I had to make a couple of holes by myself. Be sure you finish the object as it should be before starting printing.

These are some pictures of the result and a video of its movements:






What I have learned
I realize that making simple mechanism is very useful to fix things wherever you need. It doesn't have to be very complicated ones to work well. With some simple PLA objects and some screws is quite easy tro create mechanism. The handlebar worked fine and the case was fix in the mast without problems, same with the pantilt, which it was a bit diffcult to aligned some specific pieces but at the end it worked well.

You can download all the files related to this week here.