Sensors detect a free space by sensing the presence or absence of a metal vehicle over it and sending that state, in real time, to the cloud — which relays the information to the driver's app. It's like having a "switch" in every space: on (occupied), off (free). The difference from old-style enforcement is that no one needs to walk around checking space by space; the space itself reports its status.
How the sensor "feels" the car
The most common technology relies on the vehicle's effect on the Earth's magnetic field. A car is a large mass of metal: when it parks over the sensor, it distorts the local magnetic field, and the device reads that variation as "occupied." When the vehicle leaves, the field returns to normal and the state switches to "free." There are also sensors that combine this measurement with motion detection or short-range radar, increasing accuracy and reducing false positives (such as a light motorcycle or a passing metal object).
Where the sensor sits
- In the ground: embedded in the asphalt or fixed to the surface of the space, powered by a long-life battery.
- Overhead/side-mounted: on poles or walls, aimed at the space, common in areas where opening the pavement is undesirable.
- By camera: a single camera can monitor several spaces through computer vision, identifying which are occupied in the image.
How the information reaches you
Detecting the change is only the beginning. The sensor needs to communicate that state:
- The device records the transition (free ↔ occupied).
- It sends the signal over a long-range, low-power wireless network designed for thousands of sensors spread across the city.
- The cloud updates the occupancy map.
- The app shows the available space — in cities served by Areatec, this appears in Digipare, helping the driver head straight to an area with an open spot.
Why this matters for the city
Knowing in real time which spaces are free reduces the time drivers spend circling in search of a spot — one of the biggest sources of congestion and pollution in city centers. The same data feeds Areatec's intelligence engine, Aretron, which analyzes occupancy patterns to support mobility decisions, such as adjusting charging areas and understanding peak-demand hours.
Detection summary
| Method | How it detects | Characteristic |
|---|---|---|
| Magnetic ground sensor | Distortion of the magnetic field by metal | Low power, installed in the space |
| Radar/motion | Wave reflection / change in the scene | Good against false positives |
| Camera + computer vision | Analysis of the space's image | One camera covers several spaces |
In the end, the "magic" is simple: the space stopped being passive and started reporting its own status, in seconds, to whoever is looking for somewhere to park.