Jul 8, 2025
OurCity is a hybrid physical-digital city-building game that teaches empathy and spatial reasoning to children aged 7–10. By placing sensor-equipped blocks on a physical board, players receive dynamic, projected feedback from in-game characters who guide them through emotionally-driven prompts. The game encourages collaboration, role-playing, and real-world urban planning concepts in a playful, age-appropriate format.
I co-developed the interaction design, fabricated the board, engineered all sensing and logic electronics, and collaborated with our Unity developer to integrate real-time feedback.
Project Goal
Design an interactive play system to help children practice empathy by building cities for fictional residents with diverse needs.
Concept
Players enter a fictional storyline—like Loaf-A-La Town or Knightingsdale—and help residents rebuild their city. Each round, in-game characters prompt players with needs ("place a hospital near the senior center", or "make sure the power station is central to the city"). As players construct physical buildings, the system detects their placements and triggers feedback and animations in a projected digital twin.
This interaction teaches decision-making with consequences and encourages discussion, collaboration, and imaginative worldbuilding.
 |
Resident characters like Kelly and Zeek provide context, needs, and feedback, simulating real-world community concerns.
Gameplay Loop
Choose a storyline (Atlantia, Knightingsdale, etc.)
Meet the characters and receive building prompts
Physically build on the shared board using sensor blocks
System detects structures, updates the projection
Characters give feedback, and the city evolves
Technical System
I led development of the sensing system that underpins the game's interaction model.
Block Detection: Used stacked variable resistors integrated with copper tape and a custom MUX circuit (CD4051) to identify unique combinations of buildings.
No Internal Wiring: All detection is handled via contact-based resistance changes—blocks don’t require power or internal circuits, only a resistor and taped contacts.
Real-Time Feedback: Arduino reads values and sends them to Unity, triggering character responses and environmental animations.
Blocks use passive components—resistors and copper tape—to be uniquely identified via analog signals.
Custom Arduino + MUX system polls all zones and transmits unique analog profiles to Unity in real time.
Fabrication Process
I built the board using layered acrylic and wood, laser-cut to fit our detection zones and wiring. I prototyped block components in Solidworks and iteratively refined connections to ensure durable, kid-friendly interaction. Testing showed the importance of:
Tight contact between copper pads and board surface
Blocks large enough for grip but small enough for multi-user gameplay
Sturdy fabrication to withstand stacking and repeated use
Caption: “Prototyped building blocks and accessories were refined for grip, stackability, and consistent electrical contact.”
Board consists of 3 functional layers: road pattern, detection surface, and electronics base.
User Testing + Reflection
We tested with children and peers to evaluate learning engagement and technical reliability.
What worked well:
Kids immediately role-played based on character prompts (“I want to build the hospital near my grandma”)
Collaborative decisions encouraged empathy and compromise
Sensor system correctly identified buildings >95% of time
What we improved:
Resistor spacing for easier detection
Stronger contact pressure via lip design
More guided prompts for early rounds to reduce friction
Ultimately, OurCity turned kids into tiny urban planners—balancing design constraints, neighborhood needs, and imagination.
Reflection
OurCity was a deeply interdisciplinary project. I translated abstract educational goals—like empathy and collaboration—into a tangible, playable system. Designing the sensing and fabrication pipeline required thinking across hardware, interaction, and pedagogy.
We wanted kids to feel agency and ownership while being nudged toward more thoughtful, connected design decisions. I’m proud of the technical design and how it supported those broader goals.
