Self Parking is a automatic parking system found in modern cars. It makes use of various sensors like cameras, sonars, infrared rangefinders etc. to gather information about the surroundings of a car and then use complex processing algorithms to park the car without the help of the driver. It is different from parking assistant systems which helps the actual human driver by providing information about the surroundings. Automatic parking is thus a marvel which we are going to see in almost all the cars of tomorrow. Automatic parking is less error prone than human and can make better utilization of scarce and tight parking spaces.
After seeing an ad of the new Volkswagen Passat, I had an urge to do something with a toy car. I found a GP2D120X Infra-Red distance sensor manufactured by Sharp in my parts bin and decided to use that with an AVR microcontroller. Since there was only a single distance sensor, I could not implement parallel parking since it requires sensors at the front, rear and sides. So I choose the option of perpendicular parking.
The car was made of wood and two DC motors with gearsets were fitted to power the robot. The car was powered by a 6V Lead -Acid battery.The circuit consisted of the AVR microcontroller, motor driver, and a voltage regulator, and is given below. Note that the power supply of the microcontroller is not indicated in the circuit, and a regulated 5V should be given to it
The distance sensor outputs an analog value depending on the distance of the object infront of it. This value is sampled by the ADC of the microcontroller. It then compares this value with a threshold (which depends on the length of the car) and if the value s above the threshold
The circuit diagram is given below:
All the relevant files are here. Here is a video of the car in operation