Champaign-Urbana Community Fab Lab
Champaign-Urbana Community Fab Lab

3D Printing – Craig Santo

Part 1 (in class)

Part 2

Concept Sketches

Originally, I thought I’d end up doing the Terrible Silverware Set, but I ultimately ended up going forward with the Card Holders because I wanted to design something that I knew I’d definitely keep and use.

I decided to learn Fusion360 to build the card holders, and this was definitely the most difficult part of the assignment. In my opinion, it was worth it to learn a more powerful modeling tool, because playing with many of the options, even if they didn’t get used in my design, has started inspiring me for the final project.

The “core” of the design is relatively simple – a 1.5″ high box, with a 4″ x 3″ base with a 10mm fillet. That’s what’s pictured on the left. On the right is my first draft of the bottom piece that holds the stacked boxes together. Even though I liked how it looked, I realized that the bottom would need to have a harder cut-off, so the stacked boxes simply didn’t slide off of each other. Additionally, in the concept art, the bottom piece also acts as an insert inside of the box that the cards can rest in, but I realized that this wouldn’t provide any benefit, and the cards not at the bottom would slide around anyway.

I was fairly happy with how the main part of the holders turned out – it was the simplest part of the design, anyway. I played with the bottom piece a bit more though, eventually making its shape a just a smaller version of the main box. I then figured that hollowing out the base, leaving only its rim, would save on materials. In retrospect, this wasn’t the case due to printing logistics – plenty of material was still used in building a bed for the print to sit on.

More difficulty came in learning the tool, and making sure things were nice and centered. For instance, in scaling pieces, I needed to calculate non-uniform scaling, and figure out how to translate the scaled pieces to the proper position. For example, the base of the box is a scaled-down version of the box’s dimensions – but I wanted to change the base’s x and z scale such that both had an equal rim size (uniform scaling leads to unpleasing distortion). Here’s a sample of that math. I scaled the 3″ side down to 90% of its original side, and had to calculate how to scale the 4″ dimension to maintain a constant rim-size (the answer was 92.5%).

4in -> 101.6mm
3in -> 76.2mm

76.2mm * .9 = 68.58mm
76.2mm – 68.58mm = 7.62mm

101.6mm – 7.62mm = 93.98mm
93.98mm/101.6mm = .925

The top piece was fairly simple. The above image shows the underside of the box’s top – it’s ultimately two concentric rims. The tops of the box’s sides sit between the two downward facing rims, “locking in” slightly. In retrospect, the top/locking mechanism is the thing I’d like to change the most. At the very least, lengthening the outer rim would make it more secure fairly cheaply. Unlike the base of the box, the lid’s hollow nature did save on material costs – given that I printed the top upside-down, no bedding was really necessary.

I’m pleased with how the final product turned out. Though they’re relatively simple, I got a lot out of designing them, and a simpler design was ultimately a better design. It’s something that other people could easily use, either printing as-is or changing the design dimensions slightly to fit different card decks, perhaps for other games or something. They’re also pretty easily to customize with stickers or something.

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Assignment 4: 3D Lab

This week, we are exploring 3D printing and 3D scanning. This is really exciting as while I have 3D printed something for one of my classes previously, I have never actually designed the product nor have I 3D scanned something.

Castle made on TinkerCAD
Monster on Meshmixer
3D Scanning of myself

After we scanned ourselves, I was surprised by how easy and quick it was to 3D scan. Using the inspector and auto correct feature on Meshmixer, I was able to delete off the unwanted parts of the Scanned diagram.

For the second part of the assignment, I decided to design some flatwares for my enemies. I have combined the idea of a spoon, fork, and knife into the flatware. Although Meshmixer has more features, after playing around with TinkerCAD and Meshmixer I decided to design my flatware on TinkerCAD since it is much more easier to use.

Since it is for my enemy, I designed it so that it is impossible to use. The first flatware is a combination of a spoon and a fork. However, there is a big hole in the spoon, thus no food can be picked up. The fork is also inside the hole of the spoon. This also prevents food to be picked up. The second flatware is a combination of fork and knife. Here, the ends of the fork are connected, which prevents it to pierce through any food. The knife is also in the middle prong of the fork. Since the length of the knife is shorter than the prongs of the fork, it’ll not be able to pick up anything. To make it even more impossible to use, I have made the handles of the flatwares to be really short.

Impossible Flatwares
Spoon+Fork & Fork+Knife
Final Print of the Impossible Flatware

Once my final design was printed, I decided to connect the two flatwares together with a string of ribbon so that it’s even more abstract than before!

Overall, I think that this 3D printing assignment is very interesting and very exciting to me. While it is much easier to pick up how to use TinkerCAD, I think that it’s harder to pick up the skills to use Meshmixer. Since my current flatware is actually flat, if I were to improve on it, I would try to make the flatwares to be more curved (just like real spoons).

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3D Printing/Scanning

This is my idea sheet for this project.
This is my first 3D model I created in class for the castle and the alien. I really like my alien because it’s kind of cute with its ice cream cone sticking into his head.
This is the side of the 3D model of myself scanned. It was kind of cool and sad to find out how hunched I am. It reminded me to have a better posture.
This is before I exported the file and it is showing all the errors with the lines and circles. The different colors indicate different kinds of errors.
This is the model I created for the first prompt. Surprisingly it took me quite a long time to create this as I had to resize and angle all of them to make them look good together when grouped.

First Prompt
I really love cooking. My favorite dish to make is pasta. Sometimes it gets a little crazy making a good al dante pasta dish because you have to watch the noodles and the sauce at the same time. So I created a little concurrent pasta cooker. The left part of this model is the noodle cooker. The light purple cooks the pasta and the lasers in the pot will detect the noodles that are already al dante. To prevent those noodles from getting overcooked, it gets sent to the outer part of the pot which will have the noodles circling around the pot and keep them moist. When all the noodles are cooked, it will go into the swirly pipe and come out of the pipe into the saucepan on the right. the three blue swirly lines are portraying the noodles coming out of the pot. You can cook the sauce in the pot on the right and you will be able to control when to drop the noodles into your saucepan. I’m attaching the image below to show how my noodle cooker looks inside. It was a bit more difficult than I thought to create this model because the pipes were coming in all different angles so to resize and repositioning them took me quite long. I’m very happy about my model because it reflects my imagination pretty well. One downside about this model is that it cost me over $15 to use a water-soluble material and over 9 hours to print them.

Since I have some parts of my model floating in the air, I would need a support system to print them. However, that is what it would have looked like if I printed it with a normal material. The staff at the MakerSpace told me that it will look atrocious if I used the normal material to print it.
This is what it would have looked like if I used the water-soluble material. It would be very easy to remove the support system and have them look cool. However, it would cost me $15 and over 9 hours to print them. I was afraid that I would have to pay multiple times if they didn’t come out right. So I decided to not print them.

Prompt #2

This is the model I created using scanned version of myself and the tower that is in my hometown. Dabo Tower in that picture is a very well-known historic tower in my hometown city called Gyeongju in South Korea. It is a very historic city and there are a lot of towers that monumentalize royal people who have passed away. In Korea, many older generations desire to be buried in town where they were born. Since, Gyeongju is where I was born and share a lot of good memories with my family, I thought about having my afterlife self there. I wanted to change the little heads that are attached to the tower. However, I couldn’t do that because the tower is the model that I downloaded from the website and I couldn’t manipulate elements of the model. I tried to separate the segments but ungrouping was not allowed. The difficult part about building this model was to have both files in certain size in order to export it from the MeshMixer to stl. file where I can import them to TinkerCad. My head attached to the skeleton body resembles many of the historic monuments and towers in that city. I wanted to make a symbolic model that reflects my dream to spend the later life and leaving legacy in my hometown just like how respected Kings are buried in that city.

Prompt #3

This is my model I created using the famous LOVE sculpture. I wanted to recreate the model by making the letter “O” into a heart shape to emphasize its meaning of “love”. I first had to distort my scanned model to make it into a heart shape. I used various type of brushes in the MeshMixer to make it smoother and put some points to go in more. It was kind of difficult to make it into a perfect heart shape because I didn’t want to lose the main shape of myself.

This is the scanned version of me that has been shaped into an upside down heart. It’s not perfectly looking like a heart. I cut part of my arms and smoothed them out. I pull the center part to make it look like a heart.


It was very interesting to learn about 3D modeling and scanning. I am glad to know how these things do amazing things and help out a lot of people. I had a very difficult time putting my ideas into actual models. I think it will take me some time to learn how to make my imaginations into an actual thing using the 3D printer. One difficulty I had was the pricing and the timing of the printing. I think in the future, I would have those things in my mind before designing my models so complex. I’m overall happy about how my models look but I wish it didn’t cost me so much time and money to print them out.

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3D printing – Renuka Nannapaneni

I chose to model the bit of plastic used to turn a lamp on and off. I lost the knob to turn on the lamp that was given with my apartment furniture. To not loose my security deposit, I decided to print the knob.

I needed to see precise measurements of how big the barrel around the existing metal knob would be and I found that a bit difficult to do in TinkerCad (bc of the ruler tool) so I used the online software Onshape, which I’ve had some experience with, so it was much easier to see the sizes.

I ran into a problem when I was using Onshape when I tried to sketch on a rounded edge (to create the turn handles on the barrel). So then I imported my object from Onshape to TinkerCad where it was easy to drag the two rectangular pieces into the barrel. I didn’t need precise measurements for the handles so it worked very well.

These are my trial models I created during lab section in class.

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3D Printing Assignment – Youngheon Lee

For the last 2 weeks, I got a chance to work with 3D printing. From designing and scanning to even printing my own creation. To start to get familiar with the program, I got access to TinkerCAD and made a castle. It was easy and fun playing around with shapes to create my own castle. Then I made on to put some aliens in the castle with the basic shapes and other shapes such as sunglasses, peace sign and bunny ears. I even took one of the aliens to meshmixer to play around and make it more like an alien. The pictures on the bottom are my castle and aliens.

This is my castle and two aliens I made!
This is my alien after it went through the meshmixer

For the first prompt, I chose to make a chopstick for people who don’t know how to use them. I started by understanding how I use chopstick and what kind of support and guide people might need. I figured that people have hard time holding a chopstick to start with. For my chopstick, I made a ring on each piece of chopstick so people can put it on and get an understanding of where the finger should be placed. One piece obviously has ring more towards the center because that’s where the thumb will go. If you look carefully, the ring radius is slightly bigger for the thumb piece compared to the other one. (I did this from my insight that people have thicker thumb compared to their index finger) The other piece will be put on the index finger and the heart on that piece is indication of where to press when actually using the chopstick to pick up things. I also made one end of chopstick have smaller radius so, it can pick up more detailed products. The final tinkerCAD model is pictured below. (Sorry for the annoying pixels)

For my second prompt, I decided to choose an art piece and combine it with myself! I started this by scanning myself in 3D from a help from my friend. I only need my torso and face, so the scanning process was easily done through Ipad scanning. I, then, started to search for famous sculptor or painting that is modeled in 3D. As a big fan of Banksy, I started my search from there. Banksy is famous graffiti artist who is known for criticizing the modern society with fun twist to an existing objects or people. Most famous art piece would be the ‘girl with ballon’ and ‘flower thrower’. I found a 3D modeled piece of Banksy’s art named ‘policeman and ballon dog’. This is originally a wall paint and tried to mock the police by changing the K9 dog into a balloon dog.

This is me scanned, I have no idea why it’s just black but you can see the general shape.
This is the original ‘police with ballon dog’ wall paint
This is the 3D model I downloaded from Thingiverse

Then I moved scanned myself and policeman to the Meshmixer to mix! When I first imported the files, unknown error occurred and it didn’t let me mix the two. However, I re-opened the files and finally I could mix it. I didn’t really have much knowledge on Meshmixer so, I started out by transforming myself and combined it with the police. The process took a long time since I was a beginner with Meshmixer. I finally got a right mix and I did some editing. I flattened out all the neck part that was sticking out and I flattened the police uniform so I could make it similar to what I was wearing while being 3D scanned. Even though my face isn’t really recognizable, I’m still satisfied with the results. The results are shown below.

This is a process picture of my face being absorbed into the policeman’s face
This is the end product. The top of my head and the hat is actually natural when you see it from meshmixer. Sorry for the blurry picture.

Finally, I chose to make and print a Iphone stand that allows me to charge while standing up. Since most of my friends are in Korea, I face-time them a lot and the battery runs too quickly that I have to constantly charge my phone. When charging, it’s a hassle to place my phone without the cords getting tangled. So, I decided to make an iphone stand with a hole under it for the charger to go through. I started the sketch on paper and quickly moved on the TinkerCAD to make it. I also, have to search up the dimensions of iphone to make sure I get the right height and radius of the hole. I started by making the legs then moved onto make the body. I added on a longer leg to make the stand more stable. The body is made with a deep enough hole to keep an iphone in place without the stand falling back. After I designed the product on TinkerCAD, I went on to print it. The supports were created by auto-support and I did a 15% fill-in because I didn’t want to take too much time on printing. The design was already measured to scale so, no modification was needed before printing.

This is my model on TinkerCAD
This is my phone stand printing!

After 54 minutes, I got my first 3D printing done!!!! I carefully took off the supports and put my phone in it to see if the measurements were right. My phone fitted perfectly and I’m really excited to used it for myself. All throughout the process, I didn’t have much problem but if I were to print again, I will try to make the legs a little longer so I have more room for the charger. Still, I’m really satisfied with what I got and really want to print more things in the future.

This is the printed stand with the support on the bottom
This is my little stand holding up my Iphone!! I will take it home and use it right away!
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Coin sorter-3D modeling&printing

Part 1: in-class exercises


Illini castle


Added antennas and wings

3. 3D scanning:

My face (with cone hat)

Part 2: Coin sorter (3D printed part)


I saw my friend having problem with coins where he spends long time searching for quarters from piles of coins to do his laundry. I decided to make him a gift.

My friend can make better use of his time if coins are sorted.

Initial sketch:

Coins will be sorted by going through rotary sorter.
Assembly sketch.

I made 4 different parts in this project: Coin inserter, rotary sorter, body, and coin collectors for each types of coins.


1. Coin inserter

Coin inserter drawing with dimensions.
3D modeling with TinkerCAD.
Finish design

2. Rotary sorter

Rotary sorter drawing with dimensions.
3D modeling with TinkerCAD

3. Coin collectors

Coin collectors drawing with dimensions.
3D modeling with TinkerCAD

4. Body

Body drawing with dimensions.
3D modeling with TinkerCAD


Assembly order
Added collectors
Added rotary sorter
Added coin insertor and finish

Final design:

coin sorter with coins
top view
side view

Finish Product:



Like always initial planning was crucial for this project. Because 3d printing actually take a very long time, I couldn’t take a chance to fail and go for second try. I triple check dimensions and fitting of each parts before I start printing.

Accounting for tolerance

During printing process, I encounter few surprises.


Cost of 3D printing was higher than I expected. I estimated my cost around $5, but actual cost of printing was around $20.


Time duration of 3D printing is surprisingly long. Without any failure, it took over 13 hours.

3.Availbiltiy and reliability of 3D printer:

I visited Fab lab and makerlab in business building. It seems like half of the 3D printer were broken or going through repair. I was lucky that I arrived early and printer was available, but I can imagine people not finishing their project because they couldn’t find available printer.

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Response #2

Power, Access, Status: The Discourse of Race, Gender, and Class in the Maker Movement

            I think what needs to be done first, before even trying to shift the conversation away from one about needs and problems to one of assets and opportunities is to address the misconceptions. I don’t know much about the ‘Maker Space’ in general, but the article firstly points out that it’s seen as being inclusive and open. Taking from an early article I read, I think it’s important for the movement to be self-aware and understand that it’s born out of a place of privilege and sometimes, exclusivity. I think while making knows no boundaries, who qualifies as “Maker” definitely does. The article even states “only certain types of Making are truly considered as part of the culture”. I think one of the biggest disparities is definitely in classes. Making has to include a certain level of non-necessity, whereas if you make because your livelihood depends on it, you’re excluded from the movement.

            It’s important that these conversations surrounding inclusion are taking place. So many businesses and organizations often focus on diversity without paying much attention to “inclusion”. Just because you invite different people to a space, doesn’t mean that they are being made to feel welcome or even like they belong. I watched a TED talk recently that discussed this very issue. Janet Stovall makes the point that organizations need to be single-minded if they want to overcome issues as big as these. While her talk is primarily about race, her methods can be applied to class, gender, and any other characteristics that make individuals different. Stovall suggests that we address real problems, use real numbers, and enforce real consequences. She says that “diversity is a numbers game. Inclusion is about impact. Companies can mandate diversity, but they have to cultivate inclusion”. She points out that research shows that it takes 30% of critical mass for minorities to feel that their voices are actually heard.

            It’s these kinds of numbers that the Maker Space needs to work on, not how many “opportunities” there are for women. They need to set goals that are impactful and set deadlines to achieve them and have a fire lit beneath them, with consequences for failure. I think saying that women are the problem, or that minorities are the problem is a form of deflection. And I think that the Maker Space is just another example of companies not addressing the important numbers, while also ignoring the context of its conception, and the exclusivity of its semantics.

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Fulfilling a “Need”

For the Playful Design Symposium, we are creating versions of chess. For our game, we need pieces with some sort of mechanism that allows you to mark the bottom as different.

After brainstorming different methods, I settled on prototyping a twisting mechanism similar to my salt shaker at home. The idea is that as you turn the mechanism you can show or hide the crown symbol on the bottom of the piece.

Beginning to create version 1

The first version required a piece to be floating inside of everything, so I realized that wouldn’t work & scrapped it before even printing.

Version 2. The main visual differences are the addition of an axle & the deletion of a brim on the top that previously held the turning plate within the mechanism.

The second version had layers sitting on top of each other. When I printed it, it come out as one piece. The supports had glued it all together. Breaking the supports meant breaking the pieces irreparably apart.

Printing version 2 at BIF’s Makerlab.
Version 2
Version 2 separated

The third version addressed the issue of gluing things together by printing them separately. I simply gave up on 3D printing it all the way made & figured I could use superglue to attach the axle afterwards. I also gave up on the idea of a wall around the plate that spins and instead changed a cutout slice to a cutout circle.

Version 3

When this version printed, the design seemed sound, but the measurements were off. So version 4 was the same design with a larger axle & larger holes.

From top to bottom, version 4, version 3, version 2
Simply changing the size of the hole & axle meant ungrouping everything.
Version 4. In this version, as well as in version 3, I printed the pieces separately.
Version 4 assembled.

By the end of this project, I became a little more comfortable with the software, mostly through having to redo it so many times.

Lessons I applied from past projects:

Simplify- I scaled down my ambition & simplified my life by using this project to create something I already needed to create as well as by choosing to use the simplest software. Using the simplest software felt like a cop out but I didn’t need the fancy stuff & it allowed me to work on it from home.

Better Documentation- You’ll notice I still have awkward holes in the photo documentation of my project, but I did document more of the process than I have in the past. Next time I’ll probably take fewer photos but make sure they span the whole process.

Snap- I learned in Inkscape that you can turn off the snap function so that knowledge made it easier to turn off the snap function in Tinkercad.

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3D Printing Assignment

For the past two weeks, we have been taught how to use “print” 3D files using the 3D printer in the Fab Lab. The first week, Emilie introduced us to TinkerCAD. TinkerCAD is basically an easy, browser-based 3D design and modeling tool for all. She asked us to create a castle using the shapes available and make a creature to live in it. The process at first was quite hard, but I eventually got the hang of it.

After creating the creature, we were then taught how to use Autodesk Meshmixer to better our 3D creature. First we downloaded the file then imported in Meshmixer. Emilie then taught us on how to use tools to smooth out our 3D creatures and even add some extra features unto it. I decided to smooth out parts of my creature and add a human head on the creature’s forehead.

For the end of the week, Emilie told us to think of ideas based on the prompts that were given in the assignment requirement.
1. Themed Set Of utensils: I imagined a set of chopsticks that can be plugged on to add ons that are in the shape of a fork and a spoon for space saving sakes.
2. Make a part I need: I need an Apple Watch stand

The next meeting, Emilie taught us how to use the 3D scanner using two methods. The first method is using the iScanner that is connected to the iPad. My group took turns in scanning one another for the experience. It was an interesting device to use. The second method was using the Kinect which is to be connected to a computer. This method requires the person holding the scanner (ME) to be still while the subject spins. All in all it was a great experience.

This a 3D scan of my face after going some editing process in the Meshmixer software

Then Emilie told us to create the 3D model of the idea we came up from last week. After weighing my options, I was more intrigued to make my first choice because it would be more interesting than the latter choice. I used TinkerCAD to create the 3D design of the utensils. I have to admit, even though the design looks very simple, it takes a lot of time to get the measurements right and keeping everything in shape. I ended up spending about 3 hours just for the design only.

This is the design I ended up with. The indentations on the base of the spoon is where the chopsticks go in to act as a handle

I then printed the design I created in the lab. The process took a long time so I left it in the lab to print. Another thing that I realized that I needed to add some supports so that my design was cooled down correctly. I used one of the Flashforge printers because the design I had in mind was not that complicated.

I initially thought I had some errors in the design process, so it did not print correctly. However, after coming to the lab for the third time, Emilie told me that the printers I had been using were not correctly calibrated. Hence my file won’t even print. So I tried using a different printer, and after almost 2 hours of waiting, my design was successfully printed.

I tried peeling off the supports but it created defects to my original design 🙁

I was quite excited when my 3D printed utensils were ready. However, that all changed when I was trying to peel off the supports. It kinda chipped my original design, hence the chopstick end cannot fit in the indentations of the spoon/fork head. Moreover, the supports on the spoon head won’t even budge no matter what force I did to it. So this prototype needs some more adjustments in future iterations.

If I were to reiterate the process again, I would:
1. Separate the 3 items into three different files, so that I can print using different colors using 3 different printers
2. Use a bigger printer to accommodate the size of my original design
3. Create a screw mechanism at the end of the chopsticks so that it would stick to the utensil addon better.
4. Tweak the mechanisms a bit to create a support that is easy to peel and won’t ruin my design

All in all, I really enjoyed the project we had this week. I really had to channel in my inner designer to complete the project. What I realized from this project is that one needs to have a good design in order to create something. In addition, I also learned that it is okay to fail sometimes, we should take those failures as lessons and apply it to better our future iterations or other designs.

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3D Printing-1: Planning

Draft parts of the reading light.

After thinking about what I could do for the final 3D product, i have decided to make a reading light. I just started with a base (star) and the arm (hole cylinder). I hope to learn how to incorporate LED lights inside the reading light. These screenshots show the very drafty initial design of the reading light in Tinkercad.

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3D Printing Assignment

Some Background (Trash is Bad)

For the 3D printing assignment, I am printing a component I designed from scratch. Its function (allow a Pi Zero to be mounted a rod) may not be immediately apparent, but its part of a larger side-project I want to work on this semester.

My overall goal is to make a “smart trash picker,” with the goal of using location data to incentivize and analyze garbage collection within a community. A complete product would be able to detect when someone picks up a piece of rubbish using the trash picker and records the user’s current location (if they consent). At a later time, this location data could be uploaded to some cloud database for further analysis.

The trash pickers I want to use. The blue oval is where I plan to mount the Pi Zero W to the trash picker (discussed later in the blog)

Why bother augmenting garbage collection with location data? Here are some use cases that could benefit a community:

  • “Gamification” of trash collection to incentivize citizens to pick up trash off of their streets. Say for every piece of trash you pick up, you get k points. The citizen with the most points at the end of the month could be recognized with their name in the paper, on a plaque, or some other form of praise. A public leaderboard could tickle people’s competitive side (“I want to get more points than Johnny this week”), encouraging them to go out and clean up their streets.
  • Townships could use the location data to determine which areas of their territory were accumulating the most trash. Councils could use this information to determine where to place more trash cans, or to investigate if a nearby agent was the source of the surplus trash (thanks Jeff Ginger for this suggestion)
  • Greek societies could document community service hours for members by associating trash collection data with a member ID

Through this project, I am attempting to synthesize information from two classes I am taking this semester, INFO 490 (Intro to Makerspace) and CS 498 (Internet of Things), into this project that’s been sitting on my back-burner for a while.

Smart Trash Picker Design v1

To actually build this “smart trash picker,” I figured I’d need to create a few components

  • A sensor to detect when someone has picked up trash. My plan for this is to use an IR break-beam sensor embedded within the handle of the trash picker so when someone closes the handle enough, the IR beam is broken and we detect the trash collection
  • A method to record the user’s current location. My plan for this is to write an Android app that uses the GPS on the user’s phone to grab their current location, then records that location.
  • Some method to notify the app that it needs to record the user’s location when they pick up a piece of trash with the trash picker. My plan for this is to use a Raspberry Pi Zero W physically attached to the trash picker. When the IR beam is broken, a wire to the GPIO pins of the Pi Zero would notify code running on the Pi Zero to send a Bluetooth message to the Android app, requesting that the app record the current user’s location.
  • [Optional] A cloud database that the Android app can upload location data to at the end of the day, when the user has access to a WiFi network. My plan for this is to use some Azure offering (e.g. Cosmos DB). Disclaimer, I am starting as a SWE at Microsoft after I graduate.
A Pi Zero W, with a quarter for scale

The third bullet point requires that the Pi Zero W and an external power supply be attached to the trash picker. So for this 3D printing assignment, I wanted to print a mounting so that the Pi Zero could be attached to the trash picker’s rod. For prototyping, I can’t just duct-tape the Pi Zero W to the rod because the Pi Zero W has exposed computer parts that can’t tolerate rough bindings like tape or rubber bands: I need some sort of mounting to screw the Pi Zero W into, then secure that mounting to the trash picker in a more aggressive manner.

This is my first time working with CAD software and 3D printing in, so for this assignment I’m restricting my printing to just be something that the Pi Zero W can screw onto and attach to the rod of the trash picker with a rubber band/strap/hose clamp; I am consciously not printing a mount for the power supply, a full case for the Pi Zero W, or a handle to embed the IR sensors within for this assignment. Hopefully as I get more comfortable with 3D printing, I could design and print parts for those as well…but walk before you run.

Build Process For Pi Zero W Mount

Initial Measurements and Design

Before I hit the FlashForge printers, I had to take some measurements so I could design the mounting with the correct sizes. I borrowed a roommate’s calipers and measured aspects of the trash picker and some of the power supplies I might use to power the Pi Zero W. I found a schematic for the Pi Zero W as a PDF online.

Some measurements I recorded for various power supplies and the trash picker itself. The main measurement I needed was the outer diameter of the trash picker rod.

I’m studying Computer Science, so I’m not an expert in mechanical designs. Luckily, one of my roommates is studying Mechanical engineering, so I asked him how to best mount something to a cylinder (since the trash picker rod is a cylinder). He quick doodled some designs for me

Some of the rough designs drawn by my Mech E roommate.

My main takeaway was that I was going to have some mounting that was attached to the trash picker using some sort of band (hose clamp or strap), that mounting should have some circular indentation for the rod to sit in, and the Pi Zero W would be attached to that mounting using screws leftover from a fan mounting I happen to have for a Raspberry Pi 3 (both Pi models have the same sized screw holes, M2.5).

CAD in Fusion 360

I created my design in Fusion 360 partly because I wanted to try out a “more advanced” CAD design program, but also because my dad has a CNC router and I’ve read that knowing your way around Fusion 360 can help you with cutting out 3D models in wood using that CNC router.

My STL files and Fusion 360 project files can be found on a Thingiverse Thing I created–you can find it on Thingiverse here

I used “Sketches” in Fusion 360 to make a 2D drawing of the Pi Zero schematic and the main “box” of my mounting. My first sketch uses the dimensions given in the Pi Zero schematic to place the M2.5 screw holes in the right places, and then I added 3mm holes centered at the Pi’s screw holes for a reason i’ll explain later.

In the second picture, the innermost sketch (outlined by pink lines and shown in the first picture) has the dimensions of the Pi Zero W and the M2.5 screw holes positioned where they are on the Pi Zero W board. The outermost sketch has the length and width of the whole bracket itself, which are wider and longer than the Pi Zero W so to provide space for the band to wrap around each end, as well as 3mm diameter holes centered where the Pi Zero W holes are. I extruded from these two sketches to make the bracket have a 2.5mm hole throughout the whole bracket, but a 3mm cylindrical cavity for only some of the bracket; this 2.5mm diameter to 3mm diameter transition allows the screw heads to sit within the bracket without falling through the bracket. The top-down view illustrates this the best.

Then I used a 0.475 diameter cylinder to cut a circular cavity in the mounting that the trash picker rod would sit in.

I made two “final” versions of the bracket that were ready to print: v5 which added fillets on the top edges to make it easier for the band to wrap around the bracket, and v6 that did not have fillets on the top edges. I figured v5’s fillets were a better physical design, but I thought the slight overhang the fillets created would make it unsuitable to print. I decided to print v5 first and only print v6 if v5’s print failed. To my delight, v5 printed with no issues.

Printing My Model and Assembly

I saved my v5 model (a single body in Fusion 360) as an STL file and imported it to the FlashForge program for one of the Fab Lab 3D Printers. I used 15% hexagon fill and oriented the body within the printer program so the below picture was a top-down view of the print. The print took 1 hour and 12 minutes to finish.

Top-down view of the part as it was oriented in the 3D printing program

The print came out almost perfect, but I overestimated the accuracy of how the screw holes would be printed…I had to file away a small amount of the 2.5mm and 3mm openings so my screws would fit within the holes.

After the filing and a giving the screws a bit of “motivation,” the screws correctly sat within the mounting. I screwed together the rest of the screw kit to the Pi Zero W, and then screwed my printed bracket to the Pi Zero W. It was very satisfying when the screws poking out of the bracket perfectly lined up with the holes on the Pi Zero W.

Now came the best part: finishing the build. I used two (9/16″ to 1 1/16″) hose clamps to secure my printed bracket to the trash picker. With those clamps tightened, the Pi Zero W was fully secured to the trash picker and my build was complete.

Going Forward

With the Pi Zero now able to be securely fastened to the trash picker, I can move forward with other parts of the physical parts of the prototype (i.e. embed the IR sensor in the handle). I can quick duct-tape a battery to the rod to test that the system is at least functional (when I partially close the handle, the IR sensor notifies the Pi Zero W and the Pi Zero W sends a Bluetooth message or lights up an LED, and the whole system is portable). After making sure things work within the constrained environment of indoors, I can move on to making a case for the Pi Zero W, battery, and IR sensors so the whole system is durable enough to work outdoors…but that’s work for the future.

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Readings & Summaries

  • What was the author’s argument?
  • How did they support it/make the argument?
  • What key points were the take-aways?

“Why I Am Not a Maker”

The author argues that the culture surrounding making has a hierarchy of makers placed above non-makers, and she also suggests that this culture is informed by the history of making in which men and male creations were prioritized.

One of the biggest takeaways for me was that this gendered history only recognizes male creations that weren’t just, as the author puts, “for the hearth and home”. She supports this by using anecdotes from Silicon Valley and examples related to coding. But I disagree with a lot of what she says. I think a lot of makers have been recognized throughout history, as the history of inventions is a long and diverse one. Privilege and gender play a large role in the title of “maker” undeniably, but how exclusive is it really? I think a lot of “caregiving” inventions are recognized for their value as well. A lot of environmental products I believe fall under this category of caregiving in relation to the planet. A lot of inventions for the less fortunate have become really really successful and they’re not just made to make a profit or because “the world needs more stuff”. The LifeStraw water filter is a great example of this. Sure the time and resources could have been spent making another brand of vacuums, but the makers behind that project developed that product with people in mind. They tried to solve a widely ignored problem, for ethical reasons, not just financial incentives.

I think making can be a rebel movement. I think often times people make products that counteract typical capitalistic manufacturing. When products aren’t single use, when they’re long-term, and made with sustainable products that is “going up against the system” of fast, casual, disposable manufacturing.

I understand that a lot of women’s work goes unrecognized. And I completely agree. But this article is tearing down “makers” as if there’s nothing redeemable about them.

As I began to read the next article I realized that this issue, and these articles definitely require you to already be familiar with the maker space culture and I definitely am not. I don’t know who’s qualified or who’s excluded, and I feel like my knee-jerk reaction shows how much I don’t know the context. That being said, I think being exposed to the culture before reading these articles would have been helpful.

“Power, Access, Status: The Discourse of Race, Gender, and Class in the Maker Movement”

This author makes a lot of good points including that the Maker movement is white and rich, diversity and inclusion efforts shift the responsibility to women and minorities, and that the movement as a whole is being run like a brand for rich white guys rather than a movement because of financial incentive. The other backs up these claims with evidence from Make Magazine, various quotes, and statistics from the Maker Faire.

I think my main take-away from this article is that there are a lot of societal issues that effect Makers that are not only unchecked but sometimes unrecognized by the people operating in the Maker space themselves. In addition, the author calls out how some diversity efforts think it’s enough to just recruit diverse makers “and stir” and there’s a lot more than needs to be done to make these spaces accessible.

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