GPS tracker

When I was in the army, we would often have exercises where we need to setup some equipment in the field and establish a security perimeter around to prevent access from unauthorized personnel. During those exercises, the sergeants and lieutenants would sometimes disguise themselves as enemies and try to access the equipment to see how successful we would be at stopping them. I didn't like the idea of staying alert for long periods of time and instead wanted to receive some kind of warning whenever a superior would be arriving in our vicinity so I designed a GPS tracker that I intended to put on his car.

The tracker consists of two parts: A GPS beacon (black box in the picture), which is the device to track, and the tracker itself (grey box in the picture), which reports on the position of the beacon.

As such the beacon is a fairly simple device: it embeds a GPS module, NRF24L01 wireless module and Arduino pro mini to interact with the former two. Its only task is to broadcast GPS data periodically using the wireless module.

On the other hand, the tracker is also equipped with GPS and NRF24L01 modules but also a magnetometer and display. The distance and angle to the beacon can be computed based on their respective GPS locations, which can then be displayed on the screen.