simulation of physical penalty
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website racing
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TaserDerby

✨ Inspiration

The project was inspired by the desire to create a fun, high-stakes bridge between the digital world and a physical consequence. We wanted a seemingly trivial betting game to have immediate, tangible, and slightly humorous stakes. The idea was to take the abstract concept of a microscopic sperm race using a dark, blurry "microscope" aesthetic and connect the moment of defeat to a physical penalty relay, making the outcome of the digital simulation matter in the real world.

🕹️ What it does

GoonHacks: Pretty Derby runs a full-screen, physics-based simulation of microscopic racers (sperms) moving toward a top-right goal zone.

Race Setup: The user sets a difficulty threshold $T$ (Top 1 to Top 8) and places a bet on one racer.
Simulation: The game uses randomized, biased physics to drive the racers toward the goal.
Defeat Trigger: If the user's chosen racer fails to finish within the Top $T$ positions, the application sends an HTTP POST request to the linked ESP32-C3 microcontroller.
Physical Penalty: The ESP32 receives the signal and momentarily activates a connected 5V relay, administering a physical consequence (the "penalty pulse") to a separate load.

🏗️ How we built it

The project is split into two distinct parts:

Frontend (Web App)

Built using React and Vite, with all styling handled by Tailwind CSS.

We used the HTML Canvas API within a React component to handle all real-time rendering and physics simulation (a biased random walk).
The UI logic manages fullscreen modals for betting and results.
The defeat logic sends a JavaScript Fetch API POST request to the pre-configured IP address of the ESP32.

Backend (Hardware)

The code uses the ESPAsyncWebServer library to set up a lightweight Wi-Fi server.
The server listens specifically for the /lose endpoint.
Upon receiving the POST request, the code pulses a designated GPIO pin (connected to the relay's control pin) from LOW to HIGH for 2 seconds, then back to LOW.

🚧 Challenges we ran into

The primary challenge was debugging and fixing the Brownout Detection (BOD) resets on the ESP32.

When the high-current 5V relay coil was powered directly from the ESP32's VDD (5V) pin, the sudden current draw caused the voltage to drop below the chip's minimum threshold.
This caused the ESP32 to instantly crash and reboot whenever the "penalty" was triggered.
Solution: We had to implement full power isolation by removing the JD-VCC jumper on the relay module and connecting the coil power (JD-VCC) to a separate, dedicated 5V power supply. This fixed the instability.

🎉 Accomplishments that we're proud of

Successfully implementing a reliable digital-to-physical trigger using a simple HTTP request on a low-power microcontroller.
Creating a surprisingly smooth and visually engaging real-time physics simulation entirely within the HTML Canvas.
Overcoming the complex hardware-level power interference issue (the brownout) to ensure the system is robust and stable under load.

💡 What we learned

We gained valuable experience in embedded networking, particularly in:

Asynchronous server handling on microcontrollers (using ESPAsyncWebServer).
The critical necessity of power isolation and common grounding when interfacing high-current components (relays, motors) with sensitive logic components (ESP32).
Optimizing canvas rendering performance within a modern React application structure.

🚀 What's next for GoonHacks: Pretty Derby

Expand Physics: Introduce obstacles and power-ups into the microscopic environment to make the race visually more complex and strategically deeper.
Persistent Scoreboard: Add a database layer (like Firebase) to track user history and total penalties delivered.
External Data Integration: Pull external randomized data (weather, stock market fluctuations) to influence racer speeds, making the "microscope" seem like it's reacting to the world.