Traffic flow, signals & roadway geometry — how vehicles queue, merge, stop and share intersections and crossings.
Vehicles circulate through a one-kilometre equivalent road segment. Increase density and watch their spacing shrink while the equilibrium speed falls. A detector gantry connects moving vehicles to speed, density and hourly flow.
A two-phase junction serves two conflicting approaches. Change green allocation, demand and saturation discharge. Signals change through green, amber and all-red while the approach queues grow or drain.
An eastbound major road crosses a stopped minor-road movement. Vehicles, stop markings, a highlighted conflict zone and queue counters demonstrate gap acceptance and priority. A teaching fault switch disables yielding so unsafe accepted gaps can be inspected.
An instrumented car approaches a fixed hazard marker. Its first coloured track is reaction distance; the second is braking distance. Change speed, reaction time, deceleration and grade to see whether it stops before the marker.
A car travels around a circular road segment. Inspect its banked road cross-section and force vectors while changing speed, radius, superelevation and the selected friction allowance.
A side-view road cutaway connects two tangent grades with a parabola. Watch a vehicle climb the changing slope while a driver-to-object sight line reveals where the road crest blocks visibility.
A single-lane roundabout has a raised island, splitter islands, entry yield markings and moving circulating traffic. One tested entry stream accepts gaps while upstream circulating vehicles retain priority. Compare queue growth and accepted entries.
A mainline and on-ramp feed a shared bottleneck. A downstream off-ramp separates part of the discharged stream. Animate ramp metering and merge priority while comparing arrival, service and queue conservation.
A work-zone lane restriction reduces service capacity. The stopped queue length grows from cumulative arrivals minus departures, while an upstream shock-front ruler explains how congestion can propagate against vehicle motion.
A dedicated pedestrian phase begins with WALK, then a flashing clearance interval and a steady hold interval. Follow the last permitted starter and compare the configured clearance against crossing distance and walking speed.