Dealing with city hall - traffic light sensors

This is probably nowhere near the right rec.bicycle NG for this
question, but none of the other ones look right either, and because
there are a lot of smart guys here, here goes:

A few of the traffic lights on my way home from school don't respond to
my bike. I can lay it down over the easy-to-see sensor loops on the
street, but it does no good. These are at locations where the
cross-traffic is too fast and line-of-sight too short to permit plunging
across the intersection safely. And they city does not provide
crosswalks with handy "Press to walk" buttons.

I don't know if there is a specification for how sensitive the pickup
loop has to be, whether that specification is sufficient for it to sense
a bike, and how to find out whether my city's (Carlsbad, CA) sensors are
supposed to meet that spec.

I'd like to hear from anyone who has knowledge about this, and whether
anyone has a suggested strategy to approach the city's traffic
department about it.

--

Mike "Rocket J Squirrel" Elliott
71 Type 2: the Wonderbus
84 Westfalia: Mellow Yellow ("The Electrical Banana")
KG6RCR

"Mike Rocket J. Squirrel Elliott" m writes:

A few of the traffic lights on my way home from school don't respond to
my bike. I can lay it down over the easy-to-see sensor loops on the
street, but it does no good. These are at locations where the
cross-traffic is too fast and line-of-sight too short to permit plunging
across the intersection safely. And they city does not provide
crosswalks with handy "Press to walk" buttons.

When this happens to me, I make a call to the roads department of
the responsible government. Usually they fix it within a week by
adjusting the sensor or painting a bike line. Have you tried
making a call? It may not be as big a deal as you think.
--
Ben Pfaff
email:
web: http://benpfaff.org

Around here you're allowed to run such lights after a cycle, then
treating it as a two way intersection. Good law in my opinion. I
usually don't wait the full cycle if there's no traffic.

FWIW, the law was originally for motorcyclists.

If the light doesn't trip after a full cycle, the sensor is defective
and I cross against the red when traffic is clear.

Then I report to the appropriate public works department that the
sensor is defective and is forcing law-abiding road users to cross
against the red.

They're generally pretty good about going out and adjusting the
sensor -- it's not hard to do, and a lot less expensive than
defending the city from a lawsuit when someone gets hit because of a
defective sensor.

--
is Joshua Putnam
http://www.phred.org/~josh/
Books for Bicycle Mechanics and Tinkerers:
http://www.phred.org/~josh/bike/bikebooks.html

On 10/6/2005 7:15 PM Joshua Putnam wrote:

If the light doesn't trip after a full cycle, the sensor is defective
and I cross against the red when traffic is clear.

Then I report to the appropriate public works department that the
sensor is defective and is forcing law-abiding road users to cross
against the red.

They're generally pretty good about going out and adjusting the
sensor -- it's not hard to do, and a lot less expensive than
defending the city from a lawsuit when someone gets hit because of a
defective sensor.


Not safe to cross this intersection against the red, but all the more
reason for them to want to make adjustments. Thanks, guys! I'll give the
city a call!

--

Mike "Rocket J Squirrel" Elliott
71 Type 2: the Wonderbus
84 Westfalia: Mellow Yellow ("The Electrical Banana")
KG6RCR

On Thu, 06 Oct 2005 14:50:29 -0700 "Mike Rocket J. Squirrel Elliott"
m wrote:

I don't know if there is a specification for how sensitive the pickup
loop has to be, whether that specification is sufficient for it to sense
a bike, and how to find out whether my city's (Carlsbad, CA) sensors are
supposed to meet that spec.

Carlsbad? No kidding! I lived there for nearly a year in '73-4 when I
was working for Masi south of town.

Is it still a rather sleepy little town with no one there between the
age of 25 and 45?

-
-----------------------------------------------
Jim Adney
Madison, WI 53711 USA
-----------------------------------------------

"maxo" wrote:

Around here you're allowed to run such lights after a cycle, then
treating it as a two way intersection. Good law in my opinion.

He said the cross traffic is fast, and the sight lines are poor. His
objective is to get across safely (with a green light), not to justify
running a red.

Art Harris

"Mike Elliott"" wrote:

A few of the traffic lights on my way home from school don't respond to my
bike. I can lay it down over the easy-to-see sensor loops on the street,
but it does no good. These are at locations where the cross-traffic is too
fast and line-of-sight too short to permit plunging across the
intersection safely.

I don't know if there is a specification for how sensitive the pickup loop
has to be, whether that specification is sufficient for it to sense a
bike, and how to find out whether my city's (Carlsbad, CA) sensors are
supposed to meet that spec.

I'd like to hear from anyone who has knowledge about this, and whether
anyone has a suggested strategy to approach the city's traffic department
about it.

The best way to trigger the sensor is to place your wheels (vertically)
directly over one of the sensor wires. If that doesn't work, lay the bike
horizontally in the center of the loop. Don't expect the light to change
immediately after it senses your bike.

There is a sensitivity adjustment that can be made. The adjustment is
usually made to detect a car. If it's adjusted too sensitive, it may respond
to cars in the opposite lane.

Write (better than calling) the appropriate traffic safety department, and
stress the safety aspect. Ask them to either adjust or replace the sensor so
that it will detect a bicycle.

I had a very similar situation here (Long Island, NY). I contacted the town
highway department, and got an immediate response. They even painted lines
showing where to position the bicycle wheels. That sensor has been working
great for me ever since!

See:
http://draco.acs.uci.edu/rbfaq/FAQ/8i.2.html

Art Harris, N2AH

Out of curiousity, what exactly are these sensors sensing? My
presumption was always that they are some form of magnetometer, sensing
the presence of a vehicle from the ferrous mass sitting above it. A
friend says that they sense mass placed on the roadway. What is it, and
is it one more reason that I should stay with steel frames? ;-)

Matt.

Mike Rocket J. Squirrel Elliott m wrote:
This is probably nowhere near the right rec.bicycle NG for this
question, but none of the other ones look right either, and because
there are a lot of smart guys here, here goes:

A few of the traffic lights on my way home from school don't respond to
my bike. I can lay it down over the easy-to-see sensor loops on the
street, but it does no good. These are at locations where the
cross-traffic is too fast and line-of-sight too short to permit plunging
across the intersection safely. And they city does not provide
crosswalks with handy "Press to walk" buttons.

I don't know if there is a specification for how sensitive the pickup
loop has to be, whether that specification is sufficient for it to sense
a bike, and how to find out whether my city's (Carlsbad, CA) sensors are
supposed to meet that spec.

I'd like to hear from anyone who has knowledge about this, and whether
anyone has a suggested strategy to approach the city's traffic
department about it.

There seem to be left turn green lights in Chicago that don't repsond to
bicycles, or just take 45 hours to change. I just go anyways.