Cycling Tips & Stories

If you bicycle much, you have noticed that some traffic signals will detect bicycles and automatically change. Others seem to be completely oblivious to the presence of bicyclists.

The article "How to turn the signals green" has some good advice for getting those pesky signals to turn for you:

This article describes how cyclists can maximize their probability of being detected by various types of sensors. If these techniques do not work for you at a particular traffic signal, report the defective traffic signal to your local traffic engineering department. After all, cyclists also have the same legal rights as other drivers at traffic signals, and deserve signals that work for them. . . .

To maximize the likelihood that an inductive loop sensor will detect your bicycle, it is important to position your bike over the most sensitive portion of the loop. There are several common shapes of inductive loop sensors, each with a different "sweet spot" for bicycles as shown in Figure 1. The two most common shapes are the dipole loop (Figure 1(a)) and the quadrupole loop (Figure 1(b)). For either of these two loop patterns, position both wheels directly over the sawcut for the wire, choosing either side for the dipole loop and using the center sawcut for the quadrupole loop. (The center sawcut of the quadrupole has twice as many wires in it as the outer sawcuts and is a more sensitive location.) If the signal does not detect you, you may wish to try leaning the bike over toward the center of the dipole loop, or to either side for the quadrupole loop.

Related:

Links: Detection of Bicycles at Demand-Actuated Traffic Signals

Tips&Stories: How to bicycle safely in traffic--

permanent link to article: "How to turn the traffic signal green"
posted by Brent Hugh at 5/25/2007 07:19:00 PM |comment on this article