Project Arcadia is an interactive recycling station. The goal of this project is to encourage active recycling by engaging people in self-motivated interactions. We built this recycling station - disguised as an arcade machine, that calls on people to vote on two sides of a trivial argument, and takes votes with empty liquid containers. The machine counts the number of votes, and detects whether the recycled material was put in the right slot. Then it gives visual and audio feedback based on what was inserted and whether that was recycled correctly.

My Role
Experience Designer

Conducted field research to investigate the environment and discovered opportunity for improvement.
Carried out preliminary tests to collect evidence that led us to develop the solution.
Designed the experience map, fleshed out visual and audio interactions.
Figured out technical solutions to detect the input and gives the desired output.
Created the system map showing the relations between interaction status, sensors, and the processing logic.

Product Engineer

As the primary visual designer and product engineer in our team, I
Embodied our concept and turned it into a physical product design.
Built the 3D model on 1:1 scale.
Built the product physically.


Set up vote topic

Correct recycling

Wrong material

What Problem?

As Americans, we create an enormous amount of trash. The average person produces about 4.4 pounds per day (the global average is 2.6 pounds), and most of it is comprised of recyclable items.

To tackle the trash problem


Using recycled plastic to make new products saves 66% of the energy over using the virgin material. Recycling of aluminum cans saves 95% of the energy required to make the same amount of aluminum from its virgin source.

Wait... What's wrong with recycling?

While government and enterprises take initial acts to increase recycling rates, we are seeing this interesting phenomenon: Mixed trashcans always fill faster than recycle bins.


In order to understand what prevents people from correct recycling, two team members did an observation in the Georgia Tech Student Center.

Two recycle bins were in the observation area. Mixed trashcans out-numbered recycle bins and were mostly placed in the open area.

Location: Georgia Tech Student Center, First floor
Time: One hour during lunch peak time


During this one-hour lunch peak, we observed no one putting anything in the recycle bins, but mixed trashcans quickly filled up.

Why did this happen? We had some hypothesis:

  • Location: Mixed trashcans were more accessible -Most of them were in the open area close to where people sit and eat.
  • Ease of use: Most people were in a hurry and didn't even stop when passing by the trash cans. Putting trash in the recycle bins, however, requires extra time reading signs and sorting the trash.

What we learned from our observation

People won't put in extra effort to get rid of their trash -They just go to the closest trashcan and dump the trash without looking.

Mixed trashcans were placed in more accessible locations for a reason: they take less space and improve efficiency in such busy areas. It won't work to replace all of them with recycle bins.


After we figured why mixed trashcans fill faster than recycle bins, the team started brainstorming ideas. We collected more than 20 ideas in 2 brainstorming sessions, and discovered 4 themes.

  • Make recycle bins easier to read and understand
  • Shape trashcans to restrict the objects that go into it
  • Engage people in motivating interactions in recycling
  • Educate about trash problem and benefits of recycling
Pick a direction

After searching for existing solutions online and discussing the pros and cons of each idea, we thought the 3rd theme would lead us further. Because restricting the trashcan slot shape has been attempted by others, and it didn't solve the problem well. As shown in the photo of trashcans in the Seatle airport, people ignore the hints of slot shapes and put all things in the "trash" slot anyway. Educating and raising awareness has also been done a lot of times. We were afraid that it does nothing other than raising awareness. Lastly, we couldn't come up with a brilliant idea that helps people read the recycle bins and save their time separating the trash. Shaping the slots was a good attempt but it failed. So we decided to try encouraging people to spend extra time and take extra steps in recycling by making it attractive.

Initial concept

Then we started to construct the concept of an interactive recycle bin, which took the two most motivating elements: "gaming" and "competing".

How did we know if our concept works?

In order to better design the experience for a dedicated environment, we narrowed down our design space to Georgia Tech campus. Because the key to success in our approach is to motivate people to participate in a voting contest on trivial arguments. It requires every participant to have a strong ownership of the community. Thus it makes sense to choose a campus environment because it has a strong community nature.

Target Users

We created the following personas to help us resonate empathy with the users' goals, needs, motivations, and lifestyles.

We wanted to find out if our users will be truly motivated to vote on trivial topics. So we conducted a validation test to see how much participation can we receive.


Georgia Tech Architecture Building
Georgia Tech Klaus building
Georgia Tech Clough Learning Commons
Over a weekend

In a Friday night, we put together 5 sloppy voting boxes and distributed them secretly across the campus.

We retrieved the boxes on Monday morning. To our surprise, we received plenty of notes even there were fewer people during the weekend.

Proof of concept

The result was absolutely exciting. Not only did we see sticker notes in the boxes, but a lot of them were also written and commented. It proved that people cared enough that they were willing to spend the time to share their opinions.

At this point, we had solid proof that the core of our idea - "Increase motivation" was working.


Audio Interaction Design

In addition to visual interactions, we designed a series of audio tones for our recycling machine. The audio tones will provide users with prompt feedbacks of valid input, and give hints about whether the recycling was correct or incorrect.

Containers Inserted
Correct or Incorrect?

The sound of containers will immediately play once bottles or cans are inserted. Following that, the elevating tone rings if the insert is correct (cans in aluminum, bottles in plastic), and vice versa.

Visual Design

Product Engineering

I used to be an industrial designer, now it's the time where my education in industrial design and HCI come together (yes that's why I love tangible interaction design so much). I wanted the physical existance of our product to echo the golden memories of gaming in the arcade. The shape of our recycling machine resembles an arcade machine, on which each side represents one standpoint of the argument. There are 4 inserting slots (2 on each side) for disposing containers, and 2 drains for emptying remaining liquid. On the top of each side there is a digital display showing the current score of that team. The center of the front panel is reserved for visual feedback of correct or incorrect recycling.

Inside the machine there are 3 tanks. Objects made in the same material will be joined in the tanks for collection. Different tanks are connected to the slots on the front through tunnels.

To get ready for implementation, I built the 3D model on 1:1 scale in Fusion 360. The 3D model helped us get the precise measurement for the different parts of the machine.

System Design

The team spent a lot of time figuring out the technical solutions. I have made this flowchart below to explain how our system works.

The sensors we used include 4 infrared sensors, 4 self-made conductivity sensors, 2 flow sensors.

Other electronics we used to produce the audio and visual feedback are 2 LED strips, 2 7-Segment displays, and a laptop that does all the processing.

We Started Building

After several late-night Home Depot runs, our arcade machine started to embody. We assembled the entire thing with mostly wood boards, thanks to the carefully designed cut slots by David. The team's favorite part of building was painting the surface and least favorite was sanding it.

Implementing the electronics was a challenge. We used Arduino to read and control all the electronics. Our processing code runs on a laptop which we hide at the back of the kiosk.

The team had fun building it. The following group pictures were taken when we were making fun of "real human-computer interface" by mimicking "indifferent", "happy", "sad" emojis behind the kiosk. This joke inspired our final design of layering acrylic faces on the middle of the screen and edge lighting it to give feedback on correct or incorrect recycling.

Building Was Complete!

After some final touching, the building was complete. We lit the edges with fluorescence wire which was my favorite part because it brought out the arcade scent and really helped it stand out in the dark.

Video Demo

Road Tests

We rolled out our machine on the "LaunchPad Demo Day" at Georgia Tech. It attracted a lot of people to see and interact with our machine. We put together a clip of that day, and it's just fun to look at.

Video Coming soon.


I learned to design intuitive feedbacks for interactive system

Through this semester-long project, I learned a lot about designing feedback to prompt users about further interactions. The audio and visual feedbacks need to be consistent, self-explanatory and right on time. Some usual occasions are recognition, rejection, warning, confirmation.

Users don't interact with our product the way we designed to

As occurred in our road tests, people pour water into the recycling machine in order to gain more points for their teams. That ends up wasting water which is the opposite of our purpose (a bug in our code enabled counting multiple points instead of 1 during one liquid flow detection). We should include that thought in the earlier phase and design our system to be more robust.

The power of brainstorm

We pivoted a lot in the early ideation phase. The final concept resulted from a lot of creative thinking, which didn't seem to connect directly to the problem. But we proved the rationale in the later experiment.

How to collaborate in teamwork

Teamwork is more than 1 + 1. All members in a team should understand each others' skillsets and learn from others. We can create better results when we support each other and, most importantly, love what we are making!