Overview
An embedded hardware system that mounts in a trailer hitch receiver to detect and document dangerous tailgating. The device uses LiDAR for distance measurement, OBD2 for vehicle speed, and a camera module for license plate photography — all coordinated by a Raspberry Pi with intelligent power management.
The Challenge
Tailgating causes thousands of accidents per year, and victims often have no evidence to support their claims. The goal was to build an affordable, self-contained device that automatically detects when a following vehicle is dangerously close, captures photographic evidence, and logs the event with speed and distance data.
What I Built
- TF-Luna LiDAR integration for real-time distance measurement of following vehicles
- OBD2 Bluetooth connection (Vgate iCar Pro) for live speed data — tailgating thresholds adjust based on current speed
- Pi Camera Module 3 triggered automatically when tailgating is detected, capturing the offending vehicle's license plate
- Self-latching relay power circuit via GPIO — the system powers itself on when the vehicle starts and initiates graceful shutdown when it loses OBD2 signal
- Event logging with timestamp, speed, distance, and photo reference for each incident
Tech Stack
Python, Raspberry Pi Zero 2W, TF-Luna LiDAR, OBD2 Bluetooth, Pi Camera Module 3, GPIO relay control
Built by Mike Cunningham · February 23, 2026