Once a container leaves the port, the people responsible for it often lose sight of it until it arrives. Speaking with a shipping company, I learned how real this problem is: they had no way of knowing a container's condition until it reached its destination, by which point any damage, delay or theft had already happened.
I built an IoT-based telemetry system to change that. A compact sensor unit mounts on the container and tracks its location with a GPS module, so the shipper can see where it is at any point in the journey.
The unit also guards the doors. A magnetic reed switch is fixed to the door frame with a magnet on the door, so the moment a door is opened the circuit breaks and the system records a tamper event. A light sensor inside the container backs this up, since any light inside a sealed container means it has been opened.
Alongside location and door status, the unit monitors shock and tilt, temperature and humidity. The system flags tampering, route deviations, impacts and other anomalies with automated alerts.
Each reading is sent as live telemetry, so a shipping company can follow every container in real time and act on a problem while the container is still on the move, rather than discovering it at the destination.