MITSIM supports the simulation of a wide range of traffic control and route guidance devices, including intersection traffic signals (TS), yield and stop signs, ramp meters, lane use signs (LUS), variable speed limit signs (VSLS), portal signals at tunnel entrances (PS), variable message signs (VMS), and electronic route guidance devices.
Control devices can be either link-wide or lane specific. A link-wide device (e.g. VSLS, VMS) controls all the approaching traffic, while a lane specific device (e.g. LUS) controls only the approaching traffic in a particular lane. Control devices are characterized by their location (segment, lane, and longitudinal position), type, initial state, and visibility. Visibility represents the maximum distance from which the device is visible by the approaching drivers.
At any given time, the state of a traffic signal (TS, PS, ramp meters, etc.) can be blank, red, yellow, green, or blank out. The state may also indicate whether the signal is flashing and/or an arrow, representing the priority (protected, yield, or stop) of a particular movement. Stop signs are represented by flashing red and yield signs by flashing yellow.
The state of VMS (including the fixed message signs) is represented by message type (e.g. lane use and lane change regulation for trucks, ETC and HOV vehicles; lane use recommendation for local and through traffic; route guidance, etc.). Depending on the type of message, more information is specified regarding the lane and link to use, and the type (class and group) of vehicles to which the given message is relevant.
In the network database only the initial (or default) states for signal and signs are specified. The real-time state of signals and signs are managed by controllers in TMS.