This is a story of Me and Leticia’s journey on our midterm project.

We started bouncing ideas back and forth- we considered a skateboarder doing a kickflip, a trombone slide moving in and out, and many others before finally deciding to do a Whac-A-Mole inspired project. I say inspired because it only mimics the motion of moles in Whac-A-Mole, but does not actually allow one to whack the moles down.

We started with some initial sketches of our project, planning out dimensions and spacing so that we had some clear direction to develop our illustrator files.

Initial sketches for design

Not fully included in the sketches is our cam design. We decided to move forward with a snail cam design because that would give the impression of a rise, like the moles peeping out of a hole, and then an instant drop as if the moles are trying to avoid getting hit. Then, we moved over to illustrator and created the cuts that would be required for each individual piece in our design. Most of the parts could be created using the shape-builder and other tools in adobe illustrator, but for the gears we used the website “Gear Generator” We set the number of teeth to be 16, which was a trial that we assumed would work based on the spacing of the model the website generated for us.

Illustrator files (these are from the final, but the shapes are generally the same aside from a few changes and different dimensions)

Now that we had the illustrator files ready, our next step was to create a low-fidelity prototype with cardboard to check the fit and practicality of our design, and to ensure that our dimension calculations from drawings were accurate and that the product was to the proper size that we envisioned for the final. We cut out the pieces on cardboard and then began assembly, starting with the frame.

The low-fidelity frame

The frame was 20cmx20cm, and after assembling it in the low-fidelity, we liked the size and decided to move forward with those dimensions. We continued assembly, using hot glue to place the parts together until we reached our final low-fidelity prototype.

Video of Low-Fidelity Prototype

Low-fidelity prototype and video

Our low-fidelity prototype was very useful and allowed us to understand a number of things about our project that we like and that needed to change, as listed below:

Changes:

• The cam shafts were not placed in line with the holes that the moles poke out of, so we needed to ensure that they are aligned.
• The holes used to hold the moles up (not where they poke out of) are too large, and allow the moles to move too much, allowing it to get stopped by friction too easily. We needed the sides to be just small enough that the piece could slide smoothly up and down, but would not move too far out of place in the x and y direction (assuming +z is upward from the table surface).
• The cam needed to be taller. The moles were barely sticking out, so we had to make the maximum radius larger.
• We needed to design caps for the end of the cam shafts so that they would not move side-to-side.
• We needed large followers to give the bottom of the moles more surface area to glide along the cams
• Needed to make the diameter of the gears smaller, so that they would fit together

What we liked

• Verification that the snail cam would create movement, and the type of movement that we wanted
• The size of our design, not too large, almost where it feels like you’re playing with a toy.

Though there is not many bullet points for what we liked, we were happy with our low-fidelity prototype because we gained valuable insight as to what changes we would have to make. Next, we moved on to developing our medium-fidelity prototype. We made adjustments to the dimensions for the rod holes, designed different snail cams, and made appropriate adjustments to all the critiques we found from our list above. We began thinking about how we wanted to incorporate our metal piece, as well as our sign design. We decided that we wanted the handle to be made out of metal as it would be stronger than wood and functionally contribute to our design. We decided that the sign would cover the front of the moles so that the user would not see them from the front as they went up and down. We decided to leave the inner mechanisms exposed because Leticia and I agreed that we enjoy design where one can see how the product actually works. We also made the decision to attach the first layer (where the moles rest) to the sides of our supports, to see if it would be more visually appealing. We also decided that we would use two snail cams for each follower, as this would still create the same motion, but would decrease the accuracy we need to get the cam directly in the middle of the follower, and allowed us to increase the size of the snail cams without them intersecting with each other by spacing them out.

After waiting in a long queue for the laser cutter, we were able to get our cuts complete and begin assembling our medium fidelity prototype. This allowed us to see if the adjustments we made were appropriate and also allowed us to test the friction between the wood-on-wood for the cams and the followers.

 

Medium Fidelity Prototype and its parts

After it was assembled, we found that all the dimension adjustments we made were correct. The cam shafts were aligned nicely under the moles, the holes for the cam shafts were in the right place and fit the rods nicely, allowing it to spin freely, gluing the first layer to the sides did make it look nicer, and the gears moved smoothly with one another. However, now that our dimensions were mainly set for the frame, we began our battle with friction. The edges of the snail cams were not smooth after being burnt from the laser cutter, and the followers often got stuck on the cams. Additionally, we still didn’t make the hole for the mole to come through small enough, and causing the moles to still get stuck on the side. To combat this, we used two long, straight pieces of wood to make the hole smaller to see if that would make the cams rise, and they did. So, we took the measurements for the distance from one rod to another and used that for the size of the mole holes.

Also, we took a poor approach to assembling our medium-fidelity design, which gave us important insight on how to assemble our final design effectively. On the medium-fidelity project, we built the frame first and then tried to squeeze the cams and gears in, which caused extreme difficulty, and inaccuracy in the placement of our cams. For our final, we knew we would have to work slowly but surely from the inner workings out, placing and gluing one piece at a time.

In illustrator, we printed out more snail cams, made the mole hole smaller, and we also decided to change our design for how the first layer would sit. We had a bar go across the sides of the design, and we decided we would have the first mole layer sit on that, so that it received support from our side supports, making the device more durable. Finally, the size of the snail cams were satisfactory, so we kept that same design for our final prototype. Now that all the adjustments were made, we decided to move into designing our final prototype.

We cut out our wood parts, including the sign, and then began to consider our metal piece, and our post-processing methods we wanted to use for the wood and metal. For the metal piece, we decided on a handle that would be shaped like a mole. I used the waterjet cutter to cut this part, and it came out fairly nicely. I filed the edges as they were sharp immediately after the cut, and then I finished it with a smoke gray spray paint to maintain the metal look, and keep the colors consistent with our base brown colors.

Handle after spray paint

For our final assembly, we decided to use wood glue for the frame and base, and then superglue for the inner workings, as superglue was easier to apply with accuracy in smaller spaces, such as between the cams and the cam shaft. For the wood, we sanded the frame it for a nice, smoother feel to it, and specifically put extra focus into the sides of the snail cam and follower to reduce friction between them. For color, we decided to stain all parts except the inner workings (to ensure there’s no added friction) using a “classic black” but very lightly (by applying it and almost immediately wiping it off) with the vision that it would give a darker, earthy view to the product.

Staining and sanding the product

The sanding turned out as we expected, but the stain actually stained the top layer and the moles significantly more than the other parts that we. We considered reprinting and restaining but, it still had the earthy look to it that we wanted, and the fact that the top layer was dark almost made it feel like it represented dirt, so we liked the aesthetics of it enough to keep it as it was.

Now, all of the parts were ready to assemble. As stated earlier, we took our time to assemble from the inner workings to the outside frame, we also ensured that we left enough time for the wood glue to dry, so that parts were flush and it looked like a quality assembly. We placed the gears on, then the cams one-by-one, checking it with the followers each time to ensure that they were equally centered across the middle of the mole stem, so that it would go up evenly. We also used a straight edge to ensure that the snails were at the exact same orientation. Finally, we randomly oriented the snails so that the movement of the moles would be random, like in the game.

After approximately 5 hours of careful assembly, we had all our parts glued together, and we were so happy when we found that there were no serious issues with the workings of our design. Two obstacles we encountered were that the holes on the side supports did not fit the rod, and there was one piece of wood that had a ridge which caught on the follower multiple times, stopping the machine. To fix these errors, we used 1/4″ washers (same size as the rod) on the outside of the side supports to prevent the rod from moving around, and we sanded the ridge away on the follower, and the design worked like a charm. It was one of the most satisfying feelings ever to see it finally work after putting in so many hours and late nights in the OEDK (~25 hrs). Here’s a video of the final product:

Copy of Movie of How it Works (1)

And here are our slides for the project:

https://docs.google.com/presentation/d/1C3goBNbSrNDsAMvEcpOnyi7cpgYnkSONUVwOJ5gpLhY/edit?usp=sharing

Reflection:

Brendan:

Being probably the most time-intensive project I’ve worked on to date, this assignment taught me a significant amount about how I work, think, and manage my time in projects.

• I often think that others can read my mind and vision during a design, and I immediately take action, expecting my partner to help me but not communicating clearly what I am doing. I need to work on communicating my ideas clearly and ensuring that my partner and I are always on the same page when working on something concurrently.
• It is easy for me to rush ahead and be excited about seeing a design come together, and forget to focus on the details, but in order to actually have a successful project, I must plan out EVERY aspect of design and assembly, to ensure no unnecessary or easily avoidable mistakes are made. This is why I assembled the frame before the inner workings on the medium-fidelity prototype.
• Next time I work on a project, I will make a materials and tools list and gather all the things I need before working on an aspect of the project. When I utilized this in the final prototype, it made the assembly so much more successful and less stressful.
• I often let fear of failure prevent me from actually starting to work on a design, which leads me to procrastinate. I left the medium-fidelity and low-fidelity prototypes to the night before the check-ins each time because I was afraid of approaching errors, even though that is the point of the prototypes. I need to start embracing and seeking out any possible errors in design, similar to acting like I am someone who is trying to criticize my project in any way possible. For example, with the snail cams I knew that they had to be longer from the beginning, but I ignored that because I just wanted to get the parts cut out as soon as possible.
• Finally, I learned that I enjoy working in a team and I believe it is so important to have multiple perspectives on a project, but when actually performing work on one aspect of the project, I think it is important to split up the work to individuals, so that individualized methods for performing the same tasks don’t contradict and decrease efficiency.

This project was extremely valuable to my development as a designer and a team worker, and though it was tough at times, I’m so glad for it.

Cost Estimate:

Wood: 2x sheets of 1/4″ thick wood – $5.75 per

Metal: 1x sheet of Aluminum – $60.00

Overhead (OEDK laser cutter, waterjet cutter, washers, and rods) – $40.00

Labor: 25 hours of labor by two people at $25.00 – $1250.00

Total Cost: $1386.50