Collects data on vehicle flow, from detectors upstream of each intersection Is tolerant to detector failure. Uses a sophisticated traffic model to predict the effects of changes in signal timings. Includes bus priority. Optimises splits, cycles and offsets in real time and instructs signals accordingly. Optimisation is adjustable for special user needs.
Occupancy is measured every quarter second.
This creates a profile for each link, to indicate when vehicles will arrive at the stopline, modelling vehicle dispersion along the link. The model also predicts delays and the build-up of congestion as part of the efficiency index. Following optimisation, signals are adjusted to give more green time to the busiest approaches. It adjusts automatically to unpredicted changes caused by road closures, accidents, weather, road developments or other variable factors. However, the standard facilities such as operator display and commands, data entry, screen presentation and data transmission are all unique to Siemens Traffic Controls.