Champaign-Urbana Community Fab Lab
University of Illinois at Urbana-Champaign
Champaign-Urbana Community Fab Lab

Author Archive

Iteration Project


I decided to iterate my pombot from last week. I had made a skiing robot that pushed itself along on fork ski poles:

My plan for iteration had two parts. First, I wanted to add an ultrasonic sensor. The whole point of the robot is locomotion, which it can’t do if there is a wall in the way. So, I wanted to add a sensor and code to make it turn when it got close to a wall. My other objective was to make it look nicer, since part of the project was that the robot should look like the motion its emulating. For this I planned to give it a little skiing outfit with coat and hat:


Adding Sensors

I started by working to add the sensor. It was easy enough to write the code, harder to debug. Initially, I had some trouble getting anything except 0 from the ultrasonic. After adding print statements and rearranging, I figured out that it was a bad wire. Once I got it to read values, I had to get the bot to turn. My initial plan was to have only one arm rotate when the ultrasonic measured below a threshold. However, testing this on the original bot showed I needed to rethink a little:


It seemed like one arm wasn’t enough force to move the whole thing, so I changed the code to have the arms swing in opposite directions. This worked much better.



I worked off the same cup as the original, but made several changes. Most significantly, I changed out the forks because the original ones had random bits of wood on the bottom to make them taller. I also inverted the way the forks faced because it felt more stable that way.

I moved on to making the skiing outfit. I added a coat made of construction paper and a scarf made of fabric. Since the ultrasonic sensor already kind of looks like goggles, I put them in place of the eyes. Lastly, I made a little hat out of fabric. I didn’t attach the hat permanently because it got in the way when I needed to trace wires, so I didn’t want it to interfere until it worked. During this process, I also rearranged where the wires came out in the hope that they would pull back less. While thinking about the wires, I decided to make a sled, hoping that it could contain all the wiring that doesn’t fit in the cup.




Once everything was finalized, I did a bit more testing to see if my aesthetic changes affected how it worked. For better or for worse, the answer was no. My rewiring and sled didn’t fix the fact that the heavy electronic pull on the bot and stunt it’s progress quite a bit. This is why I’m holding the sled above the ground in the video. On the other hand, it still works even with new forks in a new direction, so at least it didn’t get worse. While testing, I was a bit frustrated trying to keep everything lined up correctly and sitting the right distance from the computer. Since I had a battery pack from a different arduino project, I disconnected from the computer and powered it with that. This had the disadvantage of making the electronics heavier but the advantage that it doesn’t need a computer to run.



At the end, I’m happy with my iteration. I think it moves just as well as the original but looks nicer and has more complexity. It was fun messing with the sensors and constructing the decorations, which were both things I thought about doing in the original project but didn’t have time to. I’m still a bit disappointed that the electronics present such a big barrier to it’s movement, but perhaps that can be worked on in the next iteration.

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Skiing Pom Bot

In class

     This week we got to make little robots, which was very fun. We had class on Halloween, so I decided to make a little ghost. I glued a popsicle stick to a servo and glued that into the cup so that it looked like it was waving. While working on it, I played around with how far and how fast it moved:

Admittedly, it doesn’t look very much like a ghost, but I ran out of time and it didn’t really affect the function so I never finished that part.


Final Project

     While thinking about what sort of robot I should make, I was sitting in my dorm room and my eyes wandered over my box of plastic silverware. For some reason, I was hit with the burst of inspiration to make a skiing robot, using knives as skis. I started sketching my idea:


I eventually decided to use forks for the poles since I had them on hand. I planned to have two servos act like arms to swing the poles and they would push the bot forward. I wasn’t sure exactly how I wanted to make the person, as reflected in my drawing. I wanted the bot to resemble a person skiing. However, having a figure that looks like a human balancing on skis felt like adding unnecessary complication to the bot. In the end, I used the cup from my in class assignment since he already had the googly eyes to look the part.






Adding the third servo to lift the bot


Construction wasn’t too difficult, but it took a lot of trial and error. The biggest problem was realizing that every time the arms swung back they also had to swing forward without pushing backwards. To fix this, I added a third servo to push the bot up as it swung back. This took some planning to build a piece that could support the contraption and also fit back into the cup. I also had to re-glue the servos and forks several times to get the distance from servo to ground correct. 





Holes added for the wire to sit in more convenient places


One of the frustrations I had was with the wires getting in the way of the forks, so I added holes to the cup for the wires to flow out of the top nicely. This makes the project more organized, although the angle the wires pull at sometimes stop it from locomoting unless held at a better angle.





Programming was pretty simple, too. The arms basically just had to use the sweep code. Because the servo was flipped, I did have to change the left servo to go to pos-1 while the right servo went to pos. In between the for loops, I just had to have the third servo switch between two angles that I found experimentally. In the end, I had this code:



     I’m pretty happy with my bot, though it is clearly a rough draft. For my redesign, I think I’ll keep the silverware because they sort of inspired me in the first place. However, I’d like to make the figure look a little nicer as it currently is full of random holes. I figure my second attempt will look less slapdash since I have a better idea of where things need to be glued. The coding I did for this bot wasn’t very complex, so  I’d also like to look into adding an ultrasonic sensor to make it stop if it gets close to something.

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Arduino Storyboard

In class

This week we started working with Arduinos. I already have a bit of experience with them, so I had no trouble setting up the led circuits and making them blink SOS:


However, the capacitive touch sensor gave me a bit of trouble. I got it to work for awhile, and then it would randomly stop and only give off 0’s. Every once in awhile it would go back to working for seemingly no reason. I did notice the difference between when I touched the resistor and when I touched the tin foil, so I worked on the threshold code even though I couldn’t test it very well.



Since I’m pretty familiar with Arduino, I wanted to come up with something challenging. I have a game controller and a strand of Neopixels, so I started thinking about things I could do with that. I came up with the following image:

Basically, sometimes I’m in my room just hanging out, and sometimes I’m there to study. The same goes for my roommate. I thought it would be cool for the lights to indicate to the other which one it is. For example, if one of us needs to focus the lights could be red and if not they could be blue. The color could be altered based on how long you hold the joystick.



It turns out, to actually connect the joystick to the Arduino, I needed to use a second program called Processing. Luckily, the language was basically the same as Arduino, and I was able to figure it out with the help of a tutorial. I really enjoyed working on this part, so I actually added some other modes using the buttons on the controller. After ‘A’ is pressed, the joystick controls the light color as originally planned. After pressing ‘B’, the joystick can be held back and released to fling a single pixel across the strip. Pressing ‘X’ lets the joystick control with pixel will light up so it looks like its moving:


Writing the logic for the joystick wasn’t very complicated, it just took some planning. Most notably, sometimes it was easier to keep track of variable in the Processing code and then send them to the lights, and sometimes it was easier to send raw data to the Arduino code and deal with it there. In the end, I had this code:

Even though there was a lot to think about, I had a lot of fun both making it and playing with the finished prototype.



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Sewing Project

In class:

The first week, I got to work with a sewing machine for the first time. Because of some difficulties with how it was set up I had trouble at first. Maxx was able to fix whatever was wrong and I got some practice sewing straight lines as well as curves. After that we started drawstring bags. Making the bag itself was not too hard. However, trying to figure out what should be sewn where and why was quite confusing at times.


The in-class project for the second week went a bit smoother. To get practice with embroidery, we needed a design that had at least 3 colors. I went with this shooting star design from Gravity Falls. I was able to make the patch without any hiccups, although I would face problems with embroidery later, with the final project.


Final Project:

I decided to make a box pouch patterns. I have a lot of electronics scattered around, and another container would be useful in organizing them. Therefore, I incorporated electronics into the design for my embroidery. I put a circuit around my name to make it both personalized and relevant:


When I started to construct my pouch, the first problem I faced was the embroidery. For awhile, the machine seemed to keep getting stuck and bunched up. The straight lines bordering my name turned into curves. One of the staff members pointed out that I was using a sewing machine that had a foot for sewing rather than embroidery, and helped me fix the problem. On the bright side, while failing on my first attempt I also noticed that the design was way too small, so I resized it when working on the second attempt.

Attempt #1


While sewing up the box, I ran into the same confusions as the drawstring bag. It was hard to tell what should be sewn together and how to keep the other parts out of the way of the needle. I found the first sewing step to be especially tricky, which was a disheartening way to start. However, I soon got into the swing of it and felt much better.



I have come out of this project with a new respect for sewing. On first appearance it looks pretty easy- the machine practically does it for you. But I learned about the tricky little things you don’t see – cutting the fabric the right amount, lining everything up, keeping track of which part of the fabric is on the outside or inside. Overall, I’m fairly happy about my final product, but it was quite challenging work.

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Allison Quinlan 3D Printing

Castle and Alien

My first dealings with 3D modelling went pretty smoothly. We were supposed to create a castle and an alien in Tinkercad. I played around with making holes for the windows and doors with different shapes and tried my best to get all the pieces flush with each other in the way I wanted. I made the alien by stacking a bunch of torus with a dodecahedron on top and grouping them. I also imported the alien into Meshmixer and messed with smoothing the rings to look more like a single object.


Using the scanners was very fun, if a bit tricky at first. My group had some difficulty angling the ipad to fit our subjects in the box. After some trial and error and realizing we could change the box size, we each made a scan of ourselves. In our first few scans we accidentally cutoff some body parts, but by my turn we had gotten the hang of it:

I also did a scan using the kinect. Because of the way the camera was held, the model had me leaning at a 45 degree angle, but I was able to correct for it in Meshmixer:


For the first deadline, I made these sketches:


Flatware – I decided to make flatware that is usable but very inconvenient. On first glance, it doesn’t seem that bad, but once you actually use it it seems impossible. I designed a plate that has a ton of dividers, making each section to small to hold a decent amount of food. The cup has a parabola shape so that it would spill most (but not all) its contents when set down. The silverware is attached together so that it is impossible to actually use the knife and infeasible to use the fork or spoon.

Cultural – I have lived in Illinois my whole life, so I looked into redesigning something important to the state. I’ve long thought that the Illinois flag (like most of the state flags, actually) didn’t seem to represent Illinois very well. Plus, its kind of ugly. For my design, I thought about how Illinois is often described as being nestled in cornfields, so I put a rough Chicago skyline in between some stalks of corn.

Art – The art piece I looked at is called “The Light Inside” by James Turrell. A lot of his work seems to create optical illusions using light. This piece is actually an underground tunnel with light along the sides. However, when seen in a 2D picture it almost seemed reversed. I sketched an abstract shape that makes the actual tunnel part of his piece solid and the blocks of light on the side would be carved out.

Custom Part – The part I need is some kind of organizer for my bookbag. I don’t like digging around through my calculator, pens, earbuds, and whatever else is in there every time I need a pencil. Though it looks pretty simple, I did take the time to measure out the stuff in my bookbag and make sure there was wiggle room so that I could actually fit my stuff in its dedicated compartment.



I decided to go forward with my flatware design. While creating the writeup about my sketches, I realized that a better way to categorize my design was that they are for very small serving sizes. The plate dividers keep you from piling on too much food and the cup will hold a small amount of liquid even when tipped over. The silverware didn’t really fit the theme, so I redesigned them to be tiny. It would take ages to eat a substantial amount of food with a spoon that can only hold a single pea or a knife that’s almost a chopstick.

We were warned not to underestimate how long it will take to print something, but I did anyway. I ran into several problems while trying to print my pieces. I started with the cup, which was started over twice because of jammed printers. Eventually it did come out, however I promptly broke it. There were supports keeping it upright, but when I tried to take them off I snapped the whole bottom off.

I moved on to print the silverware. Luckily, the problems I had with this one were easy to catch early, so it took less time. The first time I tried to print it I realized the bottom of the spoon was on the platform, but this bottom was lower than the rest of the object. When I tried to print, nothing was sticking because the platform was a centimeter below the nozzle. I flipped it over and printed again, and it came out fine.

The plate surprisingly went without any hiccups, although it did take the longest to print.


At the beginning of the semester I said I was the most excited about 3D printing because I’ve been exposed to it a lot but I’ve never actually used one. After doing the unit I’d say it has been the most educational so far. I learned a lot about the best ways to design and position objects for printing. For example, if I were to do the cup again I would print it upside down to avoid breaking it. I also got better at using 3D modeling software. I never realized how much thought goes into making an object the right shape and size. Overall, this experience has shown me that 3D printers are very cool, but very frustrating. I look forward to trying to use them again in the future.

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Paper Circuits

Project 1:

The first project was rather straightforward, but it was good practice at using the copper tape and making mitered corners.  I did have a bit of trouble getting it to light up at first. After some thinking I realized the battery was facing the wrong way, and it lit up fine:


Project 2:

For  the quote project, I had more freedom. I chose the quote, “Beauty is a light in the heart”. When I saw this quote I thought of an image with the LED in a literal heart. I used the other LED as the ‘i’ in the word ‘light’. I also used the copper as a decorative border and underline because I liked how it looks. I didn’t have to use a resistor for this one, but I did learn how to use the resistor calculator when checking if I needed one. I also used this project to try making a parallel circuit, which was useful when approaching my final project. 


Project 3:

I wanted to do something space themed for my final project. I liked the idea of having a star field of LEDs with a rocket. When I started sketching out ideas I also thought it would be cool to have an Earth that the rocket was lifting off from, so I added city lights down on the planet.

A sketch of my third project


I started planning my circuit as a big series circuit, because it seemed simplest. However, in a series circuit the voltage drop across each circuit adds up. I calculated that I needed 6 batteries with that design, so I decided to think about parallel circuits. In the end, I connect the star lights in parallel and the Earth lights in parallel and then connected those two circuits in series. This meant I only needed two batteries. My design was a bit too complicated to use the resistor calculator, so I used the equation to find I needed a 60 ohm resistor. 

My plan for the circuit of the stars and lights


I decided to sandwich my circuit between two pieces of paper so I would have the freedom to put copper tape wherever it was needed as well as put design elements wherever they looked good. This was helpful because I was able to easily access all bits of the circuit while troubleshooting and then cover it all up once it worked [pic]

The circuit powering my circuit

I covered the circuit with another sheet of paper to keep the circuit hidden from the design

I did have a bit of trouble with it not lighting up. I used the multimeter to determine that each of the circuits worked individually, but when I connected the switch nothing went on. I eventually realized I made the same mistake as in the first project – the batteries were backwards.


Once I had the lights working, I did some research into making the rocket and added the switch. I also added another battery. Although two was enough to light it up, I wanted the lights really bright against the dark sky. 3 batteries increased the overall voltage and therefore the current so that the lights were brighter.

Adding the rocket to the circuit

Final product!



Though this project took the most thinking so far, I really enjoyed it. I have done circuits for physics, those classes usually do something boring like light a single bulb. It was really interesting to apply the physics and math to a creative project that I was interested in. Of course, I also had difficulties. I spent a lot of time thinking about the best way to build the circuit and then wondering if I did the math right. While actually building the circuit, I learned troubleshooting techniques. In order to figure out that the battery was the problem, I had to narrow down the problem by finding out what works until I was left with what doesn’t. Overall, I’m happy with my design. My biggest problem is that sometimes the lights are a bit flickery. I suspect some of the connections aren’t very strong and simply need to be reinforced with more copper tape.

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Robot Sticker

Since the prompt says to make something original, I was inspired to use the image of something I had a hand in building in the first place. My sticker is the image of the first robot I built with my team in high school, Talos:

Build Process:

I was able to find a picture of the robot easily, but converting it to a sticker design was another matter. The image was too complex to simply split with Inkscape because the colors weren’t defined enough and no outside edges. To fix this, I used the image to trace my own design of Talos. This allowed me to be creative about what pieces should be the same color and which pieces could be excluded entirely. In the end, I had this design:

When I went to get the stickers cut, I ran into some minor errors. I initially loaded the sheet incorrectly so that the machine wasn’t holding on to the right side properly. This resulted in a scribble instead of a shape. Luckily, a very nice fab lab employee helped me load it correctly, and it worked much better the second time:

[First try in the bottom right, second try on the top left]

I expected putting all the pieces together to be the most difficult part. While I wasn’t wrong, I still think it went pretty smoothly. The pieces were smaller than I expected them to be, but with a steady hand I was able to put them in place fairly well.

[In progress on the left and finished product on the right]


Overall, I’m quite happy with my sticker. Picking out colors for each component and finding scrap pieces that were large enough was an interesting challenge, and I like the overall design I ended up with. Despite my little problem, the printing process itself was quite simple. I actually found it kind of fun lining up the vinyl to match the grid on the screen.

The trickiest part was lining up all the pieces, so if I had to do it again I would improve that. I learned that most of the design thinking in this process happens before and after using Silhouette. Figuring out what should be broken into parts and then how to put it back together took some time, but it was a fun puzzle. The cutter is quite straightforward and enjoyable to use.


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Laser Nametag

For my name tag, I wanted to do something fun and related to a fandom I like. After going through a couple of ideas, I decided make mine themed on the book/show Good Omens.

Design and Build Process

Initially, I had lots of different ideas floating around in my head, but none of them were quite complete and  I couldn’t settle on one. I decided to start making some designs, thinking that maybe when I saw them for real it would help me narrow down my options. This worked fairly well to get me to settle on the Good Omens theme.. After I chose it, however, I majorly changed the design from something like this:

to my final design:

I did this mostly because I needed to have 4 pictures/text on it and I liked how it looked better when I started adding images to the book design than the wing design.

I also encountered some problems using the machine. The color of my lines had red at 253 and a few other little things were off. Once I went back and fixed that in Inkscape, it worked perfectly!


Overall, I’m happy with how it turned out. I like how intricate the laser was able  to make the design, especially in the drop cap letters. As far as improvements go, its a little bit singed in certain parts.  Also, one of the wings ended up a bit lighter than I wanted, which could be fixed with more practice learning how the gray scale on the computer translates to the color on the real product.

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