Project: Lit
Role: Founder and Hardware Developer
Overview #
Iterations is the second phase in the development of Lit, focused on creating and testing three prototypes based on the ESP8266, ESP32-S2, and ESP32-S3 microcontrollers. These prototypes explored hardware limitations, refined key subsystems, and tested wireless synchronization for sound-reactive lighting effects. Each iteration brought valuable insights into optimizing power systems, enhancing user interfaces, and advancing networked connectivity.
Objectives and Challenges #
- Exploration of Hardware Limitations: Evaluated the capabilities of the ESP8266, ESP32-S2, and ESP32-S3 for processing-intensive tasks, including audio signal processing, network synchronization, and real-time lighting effects.
- Subsystem Refinement: Enhanced physical user interfaces, transitioning from basic buttons and potentiometers to rotary encoders paired with OLED displays.
- Power System Optimization: Improved energy efficiency, reduced noise in power supplies, and enabled seamless operation on USB power with battery preservation.
- Network Synchronization: Made use of UDP Multicast-based communication to enable synchronized lighting effects across multiple devices.
My Contributions #
1. Prototyping and Design #
- Developed three prototypes:
- ESP8266 Split Rail Controller: Tested networked sound reactivity using experimental firmware that offloaded audio processing to other devices.
- ESP32-S2 Controller: Incorporated a rotary encoder and I2S microphone for UI control and sound reactivity while evaluating its performance in audio processing. Found significant limitations in its capabilities compared to the S3.
- ESP32-S3 Controller: Added an OLED display and I2S microphone for enhanced sound-reactive functionality and user interactivity.
- Designed and fabricated custom adapter boards for microcontrollers to simplify breadboarding and prototyping.
2. Exploration of Hardware Limitations #
- Implemented experimental firmware to enable the ESP8266 to synchronize lighting effects with audio-reactive data processed on other devices.
- Conducted performance evaluations of the ESP32-S2 and ESP32-S3, identifying the latter as optimal for audio-intensive applications due to its dual-core architecture and advanced processing capabilities.
3. Subsystem Refinement #
- Enhanced user interfaces across iterations:
- Started with basic buttons and slide potentiometers.
- Transitioned to a rotary encoder paired with an OLED display for intuitive, hardware-level control of brightness, effects, and color palettes.
- Tested and refined modular construction techniques to improve the reliability and maintainability of prototypes.
4. Power System Optimization #
- Integrated a USB Pass-Through Circuit using P-Channel Mosfets and Schottky diodes, enabling simultaneous device operation and battery charging without impacting battery health.
- Reduced noise in the split-rail power supply with capacitors, achieving partial stability for the ESP8266. However, due to remaining instability, the design was eventually retired.
- Designed and tested efficient power delivery systems to support both analog and addressable LED systems, minimizing quiescent current draw and ensuring reliable performance.
5. Network Synchronization #
- Leveraged UDP Multicast-based communication for wireless synchronization across devices, enabling real-time lighting effects.
- Experimented with using a Raspberry Pi Zero W as a dedicated router for managing network operations. This approach was abandoned due to insufficient processing power.
6. Practical Construction #
- Used JST-XH connectors and custom protoboards to facilitate modular design and ease of assembly.
- Embedded LED panels seamlessly into enclosures, prioritizing aesthetics and accessibility for testing and maintenance.
Outcomes and Learnings #
- Functional Prototypes: Developed three unique controllers, each addressing specific challenges in power systems, network connectivity, and user interfaces.
- Technical Validation: Demonstrated the feasibility of sound-reactive, networked lighting systems while identifying limitations in certain hardware configurations.
- Scalable Insights: Gained a comprehensive understanding of modular design, power management, and network synchronization for future iterations.
Technical Summary #
- Skills: Microcontroller Integration, Power System Design, Sound Reactivity, Network Synchronization, Modular Prototyping
- Tools: ESP8266, ESP32-S2, ESP32-S3, EasyEDA, KiCad, JST-XH Connectors, FreeCAD, Logic Level Converters
- Features: Audio-Responsive Lighting, OLED UI, Split-Rail Power Supplies, Modular Construction, Wireless Synchronization
Gallery #
ESP32-S3 LED Controller #
Breadboard #
Layout #
Protoboard #
Product #
ESP32-S2 LED Controller #
Continuing with my experiments, and my penchant for using spare parts, I built another controller using the ESP32-S2. I equipped it with a rotary encoder, however my prime interest was in seeing how limited the S2 was compared to the S3, when being tasked with audio processing. The answer was quite - it did in fact work, however it came at the cost of UI responsiveness, with the web server often slowing to a crawl, and the audio processing time entering into the DANGER ZONE.
Breadboarding #
Assembly #
Power Pack #
Installation #
ESP8266 Split Rail LED Controller #
Looking to experiment, I created another controller for a fixed installation using some parts I had lying around. It drives a single string of 5V addressable LED’s, as well as a strip of analog 12V LED’s, both being powered from either 5V USB pass-through, or a single Lithium Polymer Battery. What’s more, using experimental firmware, I was able to have it sync to the audio reactive data from my other devices (without needing to do the processing itself).
Breadboarding #
Power Supply #
Noise #
Mainboard #
Installation #
All-Together #
Live Demo #
Ensemble #
