Our roads are designed for cars, and there are often sensors that control lights or count vehicles in the road that don't pick up bikes; I often stop at an intersection waiting for a light to change, (yes, some cyclists do stop at red lights) and find that it never does unless I go hit the pedestrian button; the sensors don't know I am there. As for pedestrians, it is almost impossible to track how many of them there are and where they are moving. Mesh Cities, a terrific new website covering the "sustainable, intelligent cities of tomorrow today", shows how a Spanish company, Libelium, may have solved this problem: they track the bluetooth signal from the phones that just about everyone carries these days. The company describes it:
Understanding the flow and congestion of vehicular traffic is essential for efficient road systems in cities. Smooth vehicle flows reduce journey times, reduce emissions and save energy. Similarly the efficient flow of pedestrians in an airport, stadium or shopping centre saves time and can make the difference between a good and a bad visit. Monitoring traffic - whether road vehicles or people - is useful for operators of roads, attractions and transport hubs.
My first reaction was that not everyone has a bluetooth equipped cellphone, but given that there is just over a cellphone per person in the USA (much less than Europe, where there are about 1.3 cellphones per person) it probably won't be long until they do. More at MeshCities
More on cyclists and pedestrians and cars:
Curing Car Vs. Cyclist Road Wars With A New Rule: "Just Don't Steal The Right-Of-Way"
Cyclists, Motorists and the Law
Green Box Biking and Safety: It's All in Our Heads