A custom LED installation shaped by a mathematical spiral pattern has been built to respond to audio input in real time. The project, developed by an independent creator, uses a Voronoi tessellation based on the golden ratio to arrange 89 individually addressable RGB LEDs in a radial configuration that mimics natural growth patterns seen in sunflowers and other plants.

The underlying algorithm begins with evenly spaced points along a radial line, each rotated by an increment of the golden ratio (approximately 137.5 degrees). This creates a spiral distribution that naturally clusters points in patterns resembling phyllotaxis, the arrangement of leaves or seeds in plants. From this point cloud, a Voronoi diagram was generated to define cell boundaries, which were then extruded into a three-dimensional lattice structure.

Each cell was designed to house a single LED, with a precisely sized cavity carved to accommodate the component. The geometry was exported and processed using CAD software, where modifications were made to prepare the model for 3D printing. After printing, translucent mulberry paper was affixed to the front of each cell to diffuse the light, creating a soft, organic glow. The paper was secured using adhesive and mechanical fasteners, though its fragility presented challenges during assembly.

The LEDs were controlled using an STM32 microcontroller programmed with custom firmware written in C++. A lookup table stored the spatial coordinates of each LED, allowing the system to calculate polar coordinates and apply mathematical functions to determine brightness and color patterns. One such pattern, a pulsating sine wave modulated by time, created a dynamic radial effect that became central to the visual output.

Audio reactivity was introduced by integrating a digital microphone (INMP441) connected via I2S interface. The microcontroller used ARM CMSIS libraries to perform real-time frequency analysis, enabling the LED patterns to shift in response to sound levels and spectral content. This allowed the installation to react to music, such as the rhythmic complexity of Jon Hopkins' "Neon Pattern Drum," with visual changes synchronized to audio input.

Initial versions of the hardware used a perfboard prototype, which proved susceptible to mechanical noise and electrical interference. To improve stability, a custom printed circuit board was designed and fabricated, integrating the microcontroller, microphone, and power regulation components. This transition required learning surface-mount soldering techniques and PCB design software, but resulted in a more reliable and compact build.

A second iteration adopted a modular approach, using five identical PCBs arranged in a ring to form a circular backplate. This design leveraged batch manufacturing constraints and simplified assembly, though hand-soldering the densely packed LEDs remained labor-intensive. The project was temporarily paused during the development phase but later resumed with support from collaborators who assisted in soldering and mechanical integration.

The system was later upgraded to use an ESP32 microcontroller, enabling wireless connectivity and local web-based interaction. Firmware written in Rust allows users to upload custom code and WebAssembly modules through a web interface, turning the installation into an interactive platform for creative coding experiments.

Future improvements under consideration include using surface-mount LEDs to reduce soldering complexity, incorporating acrylic layers for additional protection, and exploring magnetic attachment methods for the paper faces. The creator has expressed interest in eventually producing limited runs of the device for personal use or small-scale distribution, though no commercial plans have been finalized.

The project remains an example of how mathematical concepts can be translated into physical, interactive art through iterative engineering and open-source development.