There are two programs-
1)
the parking sensor program which tells the distance between the wall and robot in four divisions which are 3 2 1 0.
2)
this is the other program which starts only when sufficent light is provided. it catches the ball when the ball is thrown because of the sound sensor. when it hits an obstacle it turns back. this ends with the robot returning us the ball back.
Talking about the sensors used the ultrasonic sensor is used as a parking sensor. the sound sensor is almost invisible , it is under the claw. the touch sensor acts as a bumper and lastly the light sensor is on the top making the robot light sensetive...............................................................................................
You might be thinking why this project is called so. this is because it is just like an elephant- it can pick up up huge things with its trunk and transport them safely. one exception to this is that an elephant cannot run so fast.
pic-1-US sensor
pic-2-touch sensor
pic-3-sound sensor