Nowadays, passenger counting operations are often developed on surveys, throughout the territory and using manual procedures: even though these may be capable of providing highly accurate values, which can be taken as a reference point in analysing the precision of the automatic systems, the manual procedures are not usually homogeneous in surveys, since they inevitably depend on the operator who performs them and may also be influenced by the time of the day – early morning versus the last hours of the day – and by a repetitive task.
On the other hand, the APC (Automatic Passenger Counting) systems, can be much more appropriate and of greater interest, as related to this short analysis. It is important to underline that – even though most of them are still at a development stage – the passenger counting technologies available on the market are various and the issues of different kinds; the combinations of technologies are such that no solution can be considered to date better than others or economically preferable a priori; every solution should be analysed in detail for applying it thereafter to the actual conditions of the public transport system or company.
As for the vision people counting system, there are different counting solutions in the market, but almost all of them are based on the ability of two stereo cameras to capture images of the area under the device. These systems, which are installed above the doors, are capable of calculating passengers entering and leaving buses, trams or trains with high accuracy. These systems usually have integrated LED, so that the system can work in almost any kind of lighting conditions. The adjustable count threshold allows children to be distinguished from adults by measuring the height of the passengers.
The biggest feature of these devices is that they can record time and date information, allow users to carry out required statistical analysis in the future, and can verify all results at any time by comparing with video records. For example, Reamol people counting systems are easy to install, and according to some construction workers, the counting accuracy is more than 98%.
The analyzer is an important component of the connection between the sensor and the server (whether on-board or remote) of the APC system: it determines the number of passengers fed by the input and output according to the signal transmitted by the sensor.
As shown in Figure 7, the analyzer is connected to the following basic functional units:
Power supply (9-36V DC)
Processing based on micro control
bus interface 2
wireless transmission modem.