Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.2 9/18/84; site noscvax.UUCP Path: utzoo!watmath!clyde!burl!ulysses!mhuxr!mhuxt!houxm!mtuxo!mtunh!mtung!mtunf!ariel!vax135!petsd!pesnta!hplabs!sdcrdcf!sdcsvax!noscvax!powers From: powers@noscvax.UUCP (William J. Powers) Newsgroups: net.bicycle Subject: Re: left turns Message-ID: <998@noscvax.UUCP> Date: Thu, 4-Jul-85 15:40:25 EDT Article-I.D.: noscvax.998 Posted: Thu Jul 4 15:40:25 1985 Date-Received: Sun, 7-Jul-85 05:50:29 EDT References: <605@intelca.UUCP> <1636@reed.UUCP> <328@varian.UUCP> <2@uw-june> <331@varian.UUCP> Organization: Naval Ocean Systems Center, San Diego Lines: 29 > > In fact, these sensors are adjustable, but if the sensitivity is made > > too high, a really massive piece of metal (like a truck) > > can activate the one in the adjacent lane. This can cause problems > > like a left-turn signal going on when no one is waiting to make a left > > turn! So you see, it's not quite as simple as it seems at first. > > > Obviously, any device of this type can be misadjusted. My point > is that if the device cannot be adjusted to accomadate the opera- > tion of all vehicles-- trucks, cars, motorcycles and bicycles-- > that legally use the road then the device is inadequate and a > more reasonable system should be adopted. Also, I can't quite > believe that the sensitivity required to sense a bicycle directly > over the loop is even close to that required to sense a truck in > the adjacent lane. Even if it is, to occasionally set off a left > turn arrow when no one is there seems more desirable than not > setting it off at all for motorcycles and bicycles. > I know that in Los Angeles they have evidently solved this problem. I don't know how. Maybe some of you LAans know or can find out. Here in San Diego we have initiated a study to solve this problem. Another suggestion that might work is to add an inductor or some such resonant circuit to a bicycle that would increase its sensitivity. I do not, however, have sufficient information on the workings of these loop detectors to attempt to design such a system. If something as simple as this could be made to work the bicycling community would be greatly indebted ( not to mention the profits that might be involved ). Bill Powers