HCDE 451|Assignment 4: 3D Printed Object
The Design Challenge:
For this project, my task was to create a 3D model for prototyping physical objects that could be used in everyday life. In particular, I was asked to use the following primitive operations for 3D modelling: extrusion, revolution and boolean(adding or subtracting one object from another).
Design:
I decided to create a soap dish prototype since I feel very frustrated to clean the mess that soap left on my sink top. A soap dish can be useful to protect the sink area from soap scum and water residue.
The design process was simple. I began by sketching out my ideas and used Rhino for 3D modelling to employ extrusion, revolution, and boolean operations. Finally, I converted the 3D object to an STL file and printed using PLA filament.
Sketching:
I started by sketching out the basic structures and some potential shapes and figures for the soap dish. I first thought of designing a round-shaped soap dish, but it would take up more space than a rectangular soap dish. I also considered designing a basket-shaped soap dish, but it won’t help to prevent soap from contacting the counter.
I searched for the dimensions of different soap dishes online and finalized my design to a 5.5"×3.5"×1.5" cuboid with round edges and grooves on top. After sketching out my idea, I quickly moved on to 3D modelling the object on Rhino.
Prototyping: 3D Modeling
I started by drawing a 5.5" by 3.5" rectangle and used the Fillet operation to trim the four edges. Then, I used the ExtrudeCrv command to drive the rectangle upward in a straight line to create a solid(cuboid).
To add the grooves, I first created a slender rectangle and then used the Revolve operation to rotate the rectangle by 360 degrees to make a cylinder. The most challenging part was to move the cylinders, make them partially embedded to the cuboid and make sure the grooves have equal intervals. Finally, I used the BooleanDifference command to subtract the cylinders from the rectangular solid.
Prototyping: Printing
After 3D modelling, I converted my design to an STL file and printed it out using one of the 3D printers at the UW CoMotion Makerspace.
Analysis:
Overall, I’m very satisfied with my prototype. It fulfils its purpose and my expectations.
Challenges:
Before this design challenge, I have never done 3D printing, and it took me days to get familiar with Rhino. I watched a lot of tutorials on YouTube as well as asking my friends who are familiar with Rhino. My biggest challenge was to work on different planes in Rhino. It was difficult trying to join different components together because it was really hard to tell if the surfaces snap-on accurately.
Frustrations:
To get the model prototype, I printed three times in total since the first two attempts both failed. The first attempt failed because I was running out of filament. It was really hard to estimate whether the filament is enough to cover the entire print job, and, after the first try, I learned to look at the estimate filament weight and weigh the filament on a balance before I start to print. The printer was out of order for my second attempt so I printed three times.
Pros and Cons:
Pros: Overall, I believe Rhino is a powerful software. I think it is a professional tool made for designers and engineer. In particular, it contains a variety of commands and functions to use. The grids and measurements systems are very clear and accurate. The different planes are very helpful for 3D modelling.
Cons: It is very hard to get to know how to use each command in the beginning. The user interface seems complex which makes it intimidating to use. It takes time to get familiar with the multi-plane view.
Reflection:
I really enjoyed my overall experience using Rhino and the 3D printer. I believe 3D modelling and 3D printing are incredibly useful and empowering. It allows designers to create medium to high fidelity prototypes without spending a significant amount of money on buying materials. I’m glad that I get to learn and practice 3D modelling and printing in this project.
Prototype (2nd Iteration):
Based on the feedback I received from my instructors and peers and test out the first prototype myself, I created a second iteration. In particular, I decided to create two components: the soap dish body and a cover(see the image below). The soap dish(left) can be put inside the cover(right).
I realized when using the first prototype, even though the grooves are helpful, water tends to flow out from the side. For the second iteration, I made a flat soap dish and a cover so that water won’t be leaking out from the side.
