Go Back  Bike Forums > Bike Forums > General Cycling Discussion
Reload this Page >

Traffic sensors for signals

Search
Notices
General Cycling Discussion Have a cycling related question or comment that doesn't fit in one of the other specialty forums? Drop on in and post in here! When possible, please select the forum above that most fits your post!

Traffic sensors for signals

Thread Tools
 
Search this Thread
 
Old 10-31-03, 10:45 AM
  #1  
Bike Happy
Thread Starter
 
DanFromDetroit's Avatar
 
Join Date: Feb 2002
Location: Detroit, MI USA
Posts: 695
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Traffic sensors for signals

When I am tooling around town, I occasionally run across a traffic sensor that trips a signal red for a cross street, so that I can cross the intersection. These are usually just before the crosswalk and are embedded in the concrete. I used to just ride around in circles waiting for a car to show up and trip the signal because my bike was invisible to the sensor. Well I found that if I stop and lean the bike on it's side so the frame is parallel to the ground instead of perpendicular, then the sensor "wakes up" the light, I pick up the bike and continue on my way. I was so happy with this discovery that I rode around and tripped a few just for fun (I am easily amused, I guess).

My frame is made of steel. I was wondering if anyone can confirm this works with an aluminum frame as well.

Dan
DanFromDetroit is offline  
Old 10-31-03, 11:02 AM
  #2  
Senior Member
 
JasBike's Avatar
 
Join Date: Jun 2003
Location: CT
Posts: 496
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
I would imagine the camera just looks for a certain % of the ground in its view to be covered, and assumes that's a car.
JasBike is offline  
Old 10-31-03, 11:12 AM
  #3  
Senior Member
 
Join Date: Aug 2003
Location: Carlsbad, CA
Posts: 91

Bikes: '04 Specialized Allez Elite

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Originally Posted by JasBike
I would imagine the camera just looks for a certain % of the ground in its view to be covered, and assumes that's a car.
I was under the impression that the traffic sensors embedded in the pavement were run under an electro-magnetic circuit. When a car stops over one of the sensors, the metal of the car trips the circuit and changes the light. If this is true, it seems that laying the bike down over the sensor would have created more surface area to trip the magnetic sensor. Just a thought...
thetray is offline  
Old 10-31-03, 11:31 AM
  #4  
Bike Happy
Thread Starter
 
DanFromDetroit's Avatar
 
Join Date: Feb 2002
Location: Detroit, MI USA
Posts: 695
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
Originally Posted by thetray
... more surface area to trip the magnetic sensor ...
I think you are right. I was wondering if an aluminum frame would trip the sensor as well. I sort of doubt it, but I was wondering if anyone has tried it.

Dan
DanFromDetroit is offline  
Old 10-31-03, 11:35 AM
  #5  
Are we having fun yet?
 
Prosody's Avatar
 
Join Date: Oct 2002
Location: Chesterfield, Missouri
Posts: 930

Bikes: Fuji Roubaix, Trek 7200

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
My aluminum frame trips sensors just fine. If you can see the cuts in the pavement where the wires are imbedded, ride and stop along one to trip the sensor. If there are three cuts, ride and stop over the center one.
__________________
You're east of East St. Louis
And the wind is making speeches.
Prosody is offline  
Old 10-31-03, 11:42 AM
  #6  
Burn-em Upus Icephaltus
 
Gojohnnygo.'s Avatar
 
Join Date: Oct 2002
Posts: 2,357
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
Liked 0 Times in 0 Posts
Originally Posted by Prosody
My aluminum frame trips sensors just fine. If you can see the cuts in the pavement where the wires are imbedded, ride and stop along one to trip the sensor. If there are three cuts, ride and stop over the center one.
If that fails unclip and place your shoe cleat down on the sensor.
__________________
Sick BubbleGum
Gojohnnygo. is offline  
Old 10-31-03, 12:04 PM
  #7  
Senior Member
 
Join Date: Sep 2001
Location: Montreal
Posts: 6,521

Bikes: Peugeot Hybrid, Minelli Hybrid

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
Likes: 0
Liked 2 Times in 2 Posts
The induction loop works when an electrical conductor moves over, so an aluminum bike should work better than a steel bike since aluminum is a better electrical conductor than steel.
AndrewP is offline  
Old 10-31-03, 12:30 PM
  #8  
newbie newbie
 
georgesnatcher's Avatar
 
Join Date: Mar 2003
Location: Happy to be in FLORIDA
Posts: 633

Bikes: Titanium Indy Fab 29" mtb

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times in 0 Posts
I have a carbon bike that never trips any sensors. Like gojohnny said though if I un-clip and put my shoe right on the line I can "fool" the sensor.
georgesnatcher is offline  

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service -

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.