Safe Transportation Research & Education Center

Automated methods are commonly used to count motorized vehicles, but are not

frequently used to count pedestrians. This is because the automated technologies

available to count pedestrians are not very developed, and their effectiveness has

not been widely researched. Moreover, most automated methods are used primarily

for the purpose of detecting, rather than counting, pedestrians (Dharmaraju et al.,

2001; Noyce and Dharmaraju, 2002; Noyce et al., 2006).

Automated pedestrian counting technologies are attractive because they have the

potential to reduce the labor costs associated with manual methods, and to record

pedestrian activity for long periods of time that are currently difficult to capture

through traditional methods. Data input and storage may also be less time

consuming than with manual methods.

On the other hand, the capital costs of automated equipment may be high;

specialized training may be required to operate it; and automated devices are

generally not capable of collecting information on pedestrian characteristics and

behavior. For these reasons, automated devices are not appropriate for all

pedestrian data collection efforts.

The choice between which method is more appropriate to collect pedestrian data

must be based on the accuracy level desired, budget constraints, and data needs

specifications.

Automated Counting Technologies

Much of the research on automated pedestrian tracking devices has focused on

pedestrian detection, not pedestrian counting. Extensive reviews of pedestrian

detection technologies were conducted by Noyce and Dharmaraju (2002) and by

Chan et al. (2006). Technologies include piezoelectric sensors, acoustic, active and

passive infrared, ultrasonic sensors, microwave radar, laser scanners, video imaging

(computer vision).

Of the technologies listed above, those most adaptable to the purpose of pedestrian

counting are: infra-red beam counters; passive infrared counters; piezoelectric pads;

laser scanners; and computer vision technology. None of these devices are widely

used for the purpose of counting pedestrians outdoors, but all have some potential to

be adapted for that purpose.

This report describes each of these technologies in detail, and discusses some of

the technical strengths and weaknesses of each method. It is important to be aware

that technical limitations are only one consideration among many when choosing an

appropriate counting device. The device “packaging,” such as the method and

location of installation may be equally important. For example, the location and

accessibility of the device may create liability issues or promote vandalism.