Traffic Queue app for iPhone and iPad

This App is designed for determination of the maximum length of queued vehicles on an isolated intersection. For the App development there have been used simulation methods, which are the combination of analytical calculation and experiment, and herewith it allows to adequately reproduce a real process at a signal controlled intersection. The main component of this process is the arrival of vehicles to the intersection, namely the time intervals between cars that are described in the App by probability laws of distribution.

A user can easily increase the number of approaches to the intersection (up to 4) in the App and select the necessary number of traffic lanes at each of them (up to 3), including the location map. Moreover, it is possible to modify regulation characteristics (cycle length, of green and yellow signals) and traffic conditions at the intersection (traffic density, distribution by principal directions, proportion of trucks and buses in a traffic flow etc.).

The App gives the following results:
- Average maximum length of queued vehicles that arises at the beginning of a green signal with “k” simulations (by number of cars and in meters);
- Average maximum length of queued vehicles “per cycle” with “k” simulations (by number of cars and in meters);
- Maximum length of queued vehicles at the beginning of a green signal with “k” simulations (by number of cars);
- Maximum length of queued vehicles “per cycle” with “k” simulations (by number of cars).

A queue “per cycle” – is a queue that arises at the beginning of green signal and a number of cars that approach the intersection while the queue passes by. The end of time interval, during which the cars that are approaching green signal are counted in the App, is the moment when the last car in a queue that has arisen at the beginning of a green signal, takes off.

The queue length size at the beginning of a green signal can be used for the settlement of optimal characteristics of traffic light signals at the intersections, particularly during regulation by separate directions (signal groups). And the size of queue “per cycle” can be used to determinate the length of additional extension at the approach to the intersection, which is introduced with an aim to increase the intersection capacity.

The queued vehicles length size within this App is very close to those, which are shown by PTV Vissim specialized software, and the slightest deviations can be seen during Hyper-Erlang distribution with parameter a=3.

The App is designed for students, postgraduates and teachers of Traffic Management specialties; it will be also useful for traffic engineers at project organizations or consulting companies.