Hardware Evolution for Air Horn Project

Hardware V0: Initial Prototype

The first prototype utilized a simple setup with:

  • Small Lead-Acid Battery: Served as the power source.
  • Battery Balancer: Ensured the battery’s cells were evenly charged.
  • Fuse Box: Provided overcurrent protection.
  • Relay and Push-Button: Used to trigger the horn manually.

This version was functional but limited in scalability and convenience.

Hardware V0

Hardware V1: Upgraded Design

The second iteration transitioned to a more robust and modular setup:

Power Source

  • Car Jump Starter: Replaced the lead-acid battery.
    • These devices are widely available and can deliver the high-power 12V required to run the air compressor and trigger the horn valves.
    • Many units seem to use a connector compatible with EC5 connectors, making them a reliable and easy-to-use 12V power supply.

Control System

  • LilyGo Relay Unit:
    • Equipped with 6 relays for versatile control.
    • Features a BLE-capable ESP32 microcontroller for wireless communication and control.

Connectivity Enhancements

  • External Antennas:
    • Since the hardware is located in the frunk, external antennas ensure reliable BLE connectivity.

This upgraded design improves functionality and lays the groundwork for remote operation and enhanced usability.

Hardware V1

Summary of Improvements

FeatureHardware V0Hardware V1Hardware V2 (WIP)
Power SourceLead-acid battery and simple fuse boxCar jump starter with EC3 connectorsBracket and easy disconnect cable
Control SystemRelay and push-buttonLilyGo relay unit with ESP32Battery and Presure monitoring
ConnectivityNoneBLE with external antennas; only iOSAndroid and BLE button panel support
Other FunctionsNoneQuick Connect for Air toolsConnectors for plug in strobes or sirens
ScalabilityLimitedSoftware; scalable, but limitedHardware templates

The transition from Hardware V0 to V1 highlights significant enhancements in power management, control capabilities, and connectivity, making the system more efficient and adaptable for future iterations.

Further improvements

This project is never done and can always be improved. This is on the to-do list:

  1. Detach Horns Split the design in two so the horns are on a separate board and can also be mounted on roof rails while the compressor remains in the frunk
  2. Clean up Make wire-looms and improve overal finish of the project. Also add a bracket for the car jump starter
  3. Add Quick Connect fitting So you can also connect air pistol or tire inflator.
  4. Recreate in Fusion360 Recreate the wood template in Fusion 360 to be able to model in CAD and use CNC router to create wood templates