First Mechanical Engineering Project

In my ME 170 class, we have been learning how to use the ProEngineer Wildfire software. This is basically a CAD program that allows you to make a 3-D model and engineering drawings for any part or assembly of parts you want. Most of the time, we have a lab that accompanies each week of lectures where we learn about all the different functions we can use to make our parts, but a few weeks ago we were tasked with making a creative part of our choice, which would then be rapid prototyped on the 3-D printer in the Mechanical Engineering Lab. This was really an individual project, but one of my friends is in my lab section, and we decided to make two individual parts that could then be connected to each other to make one bigger part. We decided on making a replica of the Ark of the Covenant (the biblical box containing the original stone tablets of the 10 commandments and other holy relics). Now, since the location and even the very existence of such an object is arguable, we decided to use the interpretation of what it looks like in Indiana Jones: Raiders of the Lost Ark. I think we did a pretty good job...

Here's the Ark from the movie

This is the Ark that we made

To make the Ark, I used ProE to design the lid, while my friend designed the box it sits on. All in all, this took over 10 hours (each) for us to do. Obviously, the more complicated the design, the more time it takes to make, but there were a lot of aspects to this that were more complicated than we thought. For instance, this is not an assembly in which pieces must fit together and have a specific function. Rather, it is more of an artistic piece. The only thing we really had to collaborate on was the general design and making sure the lid fit on the box properly. Beyond that, we each pretty much did what we wanted. But, like I said, this is an artistic design, and ProE is more of a technical software. That meant that we had to make something look aesthetically pleasing, and then assign numbers and dimensions to it so it could be represented using the geometry from the software.

The base of the lid wasn't too difficult. I made a solid box and cut out quarter cylinders along the top and bottom edges, giving it the tapering edge. The hard part was then putting the angels on top. To make the angels, I actually started with the wings first. This was where I initially drew what I thought it should look like, then altered the dimensions of each line, arc, circle, and fillet so it was represented by a number (remember this software needs specific geometry, or strong dimensions, to work properly). Next, I put the two wings on either side of where I figured the angels should go, and made another shape that looked as close to a kneeling person as I could (this was especially difficult to do using only lines, arcs, circles and fillets). When both parts were finished, the files were sent to the lab where they use a process called stereolithography to make a prototype of our design. We just got the parts back the other day, and we're pretty happy with how it turned out! Overall, I think our final product was pretty close to what we had envisioned. We were definitely ambitious with this project, but I'm glad we worked as hard as we did on it because it paid off.

Our current (and final) project is one with at least 12 parts, with at least one moving relative to the other. Once again, we've chosen a pretty difficult design, but I'll post more about that later.