Easy Parking System (EPS)
The actual parking places in the building are narrow, and year after year, the cars are wider. It’s difficult to park the car without scratching the paint on each side of the car.
That’s why I develop this system with Arduino. The EPS will help you to park your car in such a parking place, with simple light indication.

The context :
Generally, the parking places in the buildings are not supplied by electricity; care must be taken about the power consumption. The EPS will be supplied by USB battery packs to reload regularly; the USB battery packs are here very useful. The battery level is monitored by a Batt-LED on the main box.
The principle:
The principle is to help the driver to park his car in the garage.

The system is made up of 3 boxes:

1. The main box contains the microprocessors, the battery (the USB battery packs) for supply, the left and right alarm lights, and the battery level light. This main box will be installed in the back wall of the parking, so the driver can see the left and the right alarm LEDs as the car enters in the parking. When a light lit, the driver must drive very carefully.
2. Two boxes contain each 1 ultra-sonic sensor which measure the distance between the left/right wall and the left/right side of the car.

These 3 boxes are connected together by cables to transmit power and signals. The cables must be shielded for protection against interference (often, high power cables are near or crossing in the underground parts of the buildings).
The two ultra-sonic sensors (one at each side of your garage) measure the distance between the wall and the side of the car. When the measure is too low (< 5 centimetres for example), the relevant light lit on the main box.

The energy saving system:
As said above, this circuit must save energy, because it is supplied by a battery. The way for that is to set the EPS (including the ultra-sonic sensors) in low-power mode when not in use. The EPS turns on by lighting your car lights for a short time: the sensors are activated during a while (some minutes for example), and then the EPS turns in back in sleep mode. So energy is saved when not in use.

Another question is the supply: as said, the USB battery packs can be used: they are easy to reload, to transport, and to connect (. . . and easy to rob if you let the garage door opened . . .). The EPS consumption is lowered as possible: depending on the battery capacity, reload will be necessary about 1 time per month. When the battery level is too low, the Batt-LED will lit on the main box.
If the EPS is installed in your garage near your home, it may be supplied by a 5 volts wall supply. Nevertheless, the energy saving system will work.

The software was developed with Arduino.