Live occupancy tracking for university buses

The problem

Students wait up to half an hour for the bus without knowing where it is, and may board to find it full and have to get off and wait for the next one. The university has no real data on crowding, so it assigns buses by guesswork rather than data — one line overflows while another runs empty at the same hour.

How it works

1. CountingTwo consecutive light beams on the door detect a passenger passing and their direction.
2. AccountThe count goes up when a passenger boards and down when one leaves, and the current count updates live.
3. PositioningThe positioning module reads the bus's location periodically.
4. SendingThe passenger count and location are sent to the server over the cellular network.
5. DisplayThe app shows the bus on the map with the number of free seats.
6. AnalysisA university dashboard shows the crowding level on each line at every hour.

Project features

• Two-way counting tells boarding from leaving passengers, so the count stays right for the whole trip.
• Live location together with free seats — the information is only fully useful to students when both are combined.
• It works without Wi-Fi: data is sent over the cellular network as the bus moves between areas.
• A crowding report per line and hour, letting the university assign buses based on real data.
• The system takes no photos and identifies no one: counting is fully anonymous using a light beam.

Expected challenges

These are the main obstacles to expect during the build, laid out clearly so you know them before you start.

• ⚠ Heavy crowding causes counting errors: two passengers passing together count as one, so periodic correction is needed.
• Direct sunlight on the door saturates the light detector and gives wrong readings.
• Bus vibration misaligns the light beam, so solid mounting is an essential part of the project.
• The cellular signal drops when moving between areas, so readings must be stored and sent later.
• Powering the device from the bus's electrical system involves voltage spikes that can damage the controller unless isolation and regulation circuits are used.

The consultation gives you a solution for each one.