Here I have made 2 wheel obstacle avoiding robotic car
The vehicles at present aren't smart. It sounds cool if it alerts when the vehicle comes close to others.
First article in series about Line Following and Lane Following with CV
You want to race with your Carrera slot cars, but have nobody who wants to play with you? So why don´t you race against an Arduino?
A small car based on Arduino platform which can be controlled using Bluetooth and a Android app.
Arduino Parking Sensor with HC-SR04 Ultrasonic Sensor