Tuesday, February 12, 2013

Hex City III

  •  With such a street network, you can do some funky things with the signals. For example: Use three-phase signals, so each of the 3 directions are 'green' in turn, for right or left turns. Or put a roundabout at each intersection. You could also make some of the legs one-way streets...
     
    SimCity Traffic network 2 - trinary. More geographically uniform, with three directions instead of 2.
     
    The signals alternate by street color. For example: At a given intersection, on red's 'turn': Cars on a red street may turn left or right, cars on a green street may turn right, and cars on a blue street may turn, but must yield. Then it's blue's turn, then green's, then red's again. 
     
    At any intersection, 4 of the possible 6 turning movements are being made at any given time. Traveling in as straight a line as possible, a driver will have to make a left 50% of the time. At a given intersection, 33% of the time they will immediately be able to make a left. So chances of stopping (for a straight path) at any given intersection are about 1 in 6. Half of those stops will require waiting for one color to go, and half for two colors to go. 
     
    Single and double lanes only. The grid-scale is analogous to secondary arterials, at mile to half-mile spacing. 
     
    High-traffic places would have traffic arrows to tell you when you can go. Medium traffic places would have a two or 3-way stop, and low-traffic locations would have zero or one stop-sign.