V2V Collision Avoidance

# Overview **V2V Collision Avoidance** is an advanced driver assistance system (ADAS) built on **Vehicle-to-Vehicle (V2V)** communication. Every car on the network continuously broadcasts its own motion state — speed, heading and position — and each car combines what it receives from its neighbours with its onboard sensors to detect an imminent collision and warn the driver in time to react. A camera or a radar only sees what is in front of it. A V2V link reaches around blind corners, past obstructing vehicles and into blind spots — a vehicle knows about the car it cannot see. When the driver does not respond to the warning, the system brakes the car itself. --- # Safety Applications The system implements five cooperative ADAS applications: - 🛑 **EEBL — Emergency Electronic Brake Lights** A hard-braking vehicle ahead warns the cars behind it, including those with no line of sight to it. - 🚗 **FCW — Forward Collision Warning** Warns of a rear-end collision risk, and below a critical distance brakes the vehicle autonomously. - 👁️ **BSW — Blind Spot Warning** Warns that a vehicle the driver cannot see is occupying the adjacent lane before a lane change. - ⛔ **DNPW — Do Not Pass Warning** Warns against overtaking while an oncoming vehicle is approaching. - 🚦 **IMA — Intersection Movement Assist** Warns of vehicles crossing at a blind intersection. --- # System Architecture ## Main ECU — Raspberry Pi The main ECU carries the collision-avoidance logic: it fuses the sensor readings with the motion data received over the air, evaluates each of the five applications and drives the warnings and the braking action. It runs a custom **Embedded Linux** image built with the **Yocto Project**, with the project's own layer and recipes. ## Communication ECU — ESP32 Wireless exchange between vehicles runs on the **ESP32** over **ESP-NOW**, a connectionless protocol that carries short packets between peers directly, with no access point and no association delay — which is what makes it usable for a safety message. The two ECUs are linked over **UART**. ## Sensors and Actuators - **HC-SR04 ultrasonic** — obstacle and distance detection - **HMC5883L magnetometer** — heading, so a received position can be resolved into "ahead", "behind" or "in the next lane" - **DC motors with an H-bridge** — traction and autonomous braking - **LCD and buzzer** — the driver-facing warning interface --- # Software Design Each application is built as its own layered stack — application, service and hardware-abstraction layers over the drivers — so a safety feature can be reasoned about, tested and replaced on its own. The book documents the context diagram, the layered architecture and the API description for every one of the five. --- **Class of 2023 — Electronics and Communication Engineering, Faculty of Engineering, Al-Azhar University.**