Obstacle avoidance is made possible by using IR sensors which detect the obstacle. I was controlling the robotic car from my Android device and the car kept breaking because it would crash into things. So I added an obstacle avoidance system.
I have used the Arduino Uno to driver the motors using a motor driver and an IR sensor which is controlled over BLE.
I used four IR sensors which actually are used as proximity sensors to sense the obstacles in front or back or left or right side of the metal chassis thereby stopping the car before it hits the obstacle.
IR sensor which acts as proximity sensor
I use this to connect the micro controller with the Android or any other Bluetooth device.
I have used LM293D as the motor driver to drive our car using the micro controller.
Sena Bterm app
This application lets us to control our car over Bluetooth this app is the interference between our phone and the Arduino.