Stopbar
Draw roads that snap together, then run the junction as a signal, an all-way stop, or a roundabout. Signals can be fixed time or actuated. Speeds are in mph and queues are in feet.
What you can change
Drag between the dots to add a road. A third leg turns a point into a junction. Click the junction and switch it among a signal, an all-way stop, and a one-lane roundabout. Add a left pocket for a protected arrow, or a right pocket for a turn lane. On a roundabout the right pocket becomes a slip lane.
Timing starts on fixed time. Actuated rests on green until another approach is waiting, holds for a vehicle close to the bar, and gaps out about 3 seconds later. The numbers in that mode are maximum greens. Yellow stays 3.2 s and the all-red stays 1.4 s.
What the sketch leaves out
The grid is orthogonal. Roundabouts are one lane. A permitted left shares its lane with through traffic. There is no right turn on red, and editing the map clears the vehicles. The time–space diagram follows one approach. Treat the queues and delay as a way to see the phasing, then do the capacity work in a model built for the project.