N
Nobody
Guest
On Tue, 20 Jan 2009 18:58:48 -0500, Paul E. Schoen wrote:
The emergency vehicle would be stuck behind the stopped traffic.
D
DougC
Guest
Peter Rathmann wrote:
faces each direction that there are sensors. When the strobe on the
emergency vehicle triggers the traffic light system, the spotlight
facing the same direction of the triggered sensor turns on, to tell the
emergency vehicle that the traffic lights have been activated. The
emergency vehicles still do not "blast through at full speed" because
there's always people who will try to race a red light.
Sometimes even,,,, the people you'd think would know better....
http://www.youtube.com/watch?v=RM_2bERbj54
(I do not know if there was emergency triggers or not, from Google
Streetview it appears not and the news articles do not mention any)
http://maps.google.com/maps?f=q&source=s_q&hl=en&geocode=&q=taylor+avenue,+st.+louis,+mo&sll=37.09024,-95.712891&sspn=48.641855,79.101563&ie=UTF8&ll=38.657621,-90.24765&spn=0.002949,0.013733&z=17&layer=c&cbll=38.65783,-90.248117&panoid=vtnQN1M-MHYFDVx1CKSaGA&cbp=11,137.6783819425063,,0,1.5927625073623732
tinyURL:
http://tinyurl.com/9xlzau
Most are very simple to trigger, they are only analog circuits and the
pulse frequency I have heard is 30 cycles per second.... Except that (in
IL) there is a section of the state motor vehicle code that prohibits
unauthorized persons or vehicles from triggering these emergency light
systems. I would guess anywhere that has these lights will have a
similar law.
-----
Most of these things you see online (to trigger inductive loops) are
total BS. Permanent magnets will not trigger an inductive loop at all,
because permanent magnets do not display inductance at all.
I have not seen anything in my state's motor vehicle code that says that
you cannot artificially trigger an induction loop,,, so I /guess/ it
would be legal to have one on a bicycle.
As I have been told, the loops are fed a signal between ~20kHz to
~80kHz. Each loop at an intersection must use a different frequency, to
avoid cross-talk inside the control box where the loops converge--so one
frequency will *not* work for all traffic sensors. On each loop there is
a circuit to detect the phase change of the loop. The phase change you
target should probably be negative, as ferrous objects under a metal
detector result in negative phase and cars are mostly made of iron alloys.
The frequency of each loop does not change, so it might be possible to
make this device relatively simply. The device does not need to sample
the frequency and transmit it at the same time, so one antenna could do
both jobs (first sample, and then switch to transmitting).
It might work to just attach a coil antenna to a capacitor, that has a
resonant frequency of well under 20kHz. I'd think you might need a
pretty big ferrite stick to make it work well though.
You can get big 4500u ferrite rods from
http://www.stormwise.com/page26.htm
$50 each or so.
AM radio antenna ferrites will not work real well for this; AM radio is
at much higher frequencies.
~
Where I live (IL, USA) the strobe system has a while spotlight that
faces each direction that there are sensors. When the strobe on the
emergency vehicle triggers the traffic light system, the spotlight
facing the same direction of the triggered sensor turns on, to tell the
emergency vehicle that the traffic lights have been activated. The
emergency vehicles still do not "blast through at full speed" because
there's always people who will try to race a red light.
Sometimes even,,,, the people you'd think would know better....
http://www.youtube.com/watch?v=RM_2bERbj54
(I do not know if there was emergency triggers or not, from Google
Streetview it appears not and the news articles do not mention any)
http://maps.google.com/maps?f=q&source=s_q&hl=en&geocode=&q=taylor+avenue,+st.+louis,+mo&sll=37.09024,-95.712891&sspn=48.641855,79.101563&ie=UTF8&ll=38.657621,-90.24765&spn=0.002949,0.013733&z=17&layer=c&cbll=38.65783,-90.248117&panoid=vtnQN1M-MHYFDVx1CKSaGA&cbp=11,137.6783819425063,,0,1.5927625073623732
tinyURL:
http://tinyurl.com/9xlzau
Most are very simple to trigger, they are only analog circuits and the
pulse frequency I have heard is 30 cycles per second.... Except that (in
IL) there is a section of the state motor vehicle code that prohibits
unauthorized persons or vehicles from triggering these emergency light
systems. I would guess anywhere that has these lights will have a
similar law.
-----
Most of these things you see online (to trigger inductive loops) are
total BS. Permanent magnets will not trigger an inductive loop at all,
because permanent magnets do not display inductance at all.
I have not seen anything in my state's motor vehicle code that says that
you cannot artificially trigger an induction loop,,, so I /guess/ it
would be legal to have one on a bicycle.
As I have been told, the loops are fed a signal between ~20kHz to
~80kHz. Each loop at an intersection must use a different frequency, to
avoid cross-talk inside the control box where the loops converge--so one
frequency will *not* work for all traffic sensors. On each loop there is
a circuit to detect the phase change of the loop. The phase change you
target should probably be negative, as ferrous objects under a metal
detector result in negative phase and cars are mostly made of iron alloys.
The frequency of each loop does not change, so it might be possible to
make this device relatively simply. The device does not need to sample
the frequency and transmit it at the same time, so one antenna could do
both jobs (first sample, and then switch to transmitting).
It might work to just attach a coil antenna to a capacitor, that has a
resonant frequency of well under 20kHz. I'd think you might need a
pretty big ferrite stick to make it work well though.
You can get big 4500u ferrite rods from
http://www.stormwise.com/page26.htm
$50 each or so.
AM radio antenna ferrites will not work real well for this; AM radio is
at much higher frequencies.
~
R
Rich Grise
Guest
On Wed, 21 Jan 2009 07:27:06 -0600, Tom Sherman wrote:
Cheers!
Rich
Or, you could get off the bike and press the "Walk" button. ;-)
Cheers!
Rich
M
Mike A Schwab
Guest
On Jan 20, 5:58 pm, "Paul E. Schoen" <pst...@smart.net> wrote:
in the emergency vehicle. The green light lets the traffic through
and pull off to the side.
But then all the traffic in front of the emergency vehicle would block"Rich Grise" <r...@example.net> wrote in message
newsan.2009.01.20.18.37.05.434593@example.net...
deleted
I have always wondered why they did not design the strobe so that it turned
lights red in all directions. Then all traffic would stop, except for the
emergency vehicle, and the worst that an illegal strobe could do would be
to disrupt traffic and annoy people.
Paul- Hide quoted text -
- Show quoted text -
in the emergency vehicle. The green light lets the traffic through
and pull off to the side.
Guest
SMS wrote:
will notice a visible-light strobe.
I wonder if an IR or UV strobe would work? Any cop in front of you
will notice a visible-light strobe.
F
Frank Krygowski
Guest
On Jan 21, 2:32 pm, Mike A Schwab <mike.a.sch...@gmail.com> wrote:
road through a village by turning it into a boulevard. Opponents
claimed it would cause back up traffic, and that people would die in
house fires.
One of my friends is a fireman. When he heard that objection, he
laughed. He says for a fire truck or ambulance, there is no such
obstruction. They simply drive down the oncoming lane when
necessary.
- Frank Krygowski
In our area, a civic group proposed improving a certain ugly 5 laneOn Jan 20, 5:58 pm, "Paul E. Schoen" <pst...@smart.net> wrote:
"Rich Grise" <r...@example.net> wrote in message
news
deleted
I have always wondered why they did not design the strobe so that it turned
lights red in all directions. Then all traffic would stop, except for the
emergency vehicle, and the worst that an illegal strobe could do would be
to disrupt traffic and annoy people.
Paul- Hide quoted text -
- Show quoted text -
But then all the traffic in front of the emergency vehicle would block
in the emergency vehicle. The green light lets the traffic through
and pull off to the side.
road through a village by turning it into a boulevard. Opponents
claimed it would cause back up traffic, and that people would die in
house fires.
One of my friends is a fireman. When he heard that objection, he
laughed. He says for a fire truck or ambulance, there is no such
obstruction. They simply drive down the oncoming lane when
necessary.
- Frank Krygowski
T
Tom Sherman
Guest
Rich Grise wrote:
--
Tom Sherman - 42.435731,-83.985007
LOCAL CACTUS EATS CYCLIST - datakoll
<http://www.ransbikes.com/Gallery/Archive/images/Sherman1.jpg>!
--
Tom Sherman - 42.435731,-83.985007
LOCAL CACTUS EATS CYCLIST - datakoll
J
Jasen Betts
Guest
On 2009-01-21, invalid@example.com <invalid@example.com> wrote:
I saw a xenon flash front light for a bike...
M
Michael A. Terrell
Guest
Frank Krygowski wrote:
Not always possible. Some roads have large concrete barriers between
opposing lanes that would cause severe damage to the fire truck or
ambulance. I have seen ones over four feet high and several feet
thick. They are strong enough to stop a vehicle hitting it head on at
35 MPH+.
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There are two kinds of people on this earth:
The crazy, and the insane.
The first sign of insanity is denying that you're crazy.
Not always possible. Some roads have large concrete barriers between
opposing lanes that would cause severe damage to the fire truck or
ambulance. I have seen ones over four feet high and several feet
thick. They are strong enough to stop a vehicle hitting it head on at
35 MPH+.
--
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your account: http://www.usenettools.net/ISP.htm
There are two kinds of people on this earth:
The crazy, and the insane.
The first sign of insanity is denying that you're crazy.
F
Frank Krygowski
Guest
On Jan 22, 4:42 pm, "Michael A. Terrell" <mike.terr...@earthlink.net>
wrote:
eastbound and westbound lanes are separated by gullies, rivers or
cliffs. But perhaps we can agree those cases are not quite normal?
My friend was talking about the roads in his fire district, which I
know well. Nearly all American roads are similar, and present no such
problems.
- Frank Krygowski
wrote:
Admittedly, that's true. Worse yet, there are roads where the
eastbound and westbound lanes are separated by gullies, rivers or
cliffs. But perhaps we can agree those cases are not quite normal?
My friend was talking about the roads in his fire district, which I
know well. Nearly all American roads are similar, and present no such
problems.
- Frank Krygowski
C
Chris
Guest
There are two easy ways to tigger lights assuming there is an
induction loop and you have a metal bicycle (another reason to avoid
carbon fiber).
- Rare earth magnet (I am fond of expoying a pair in to the lugs of
your bike shoes, but many people use regular shoes)
- Lay the bike down in the middle of the induction loop (which is
alkward if loaded with stuff or in a busy intersection)
Some cities are starting to include bike specific sensors which
trigger lights in the United States, such as Portland, Seattle, and
Tucson, but not as many as one would hope and not as wide spread as
one would hope either. On occasion, using the Walk button, or
crosswalk is simply more practical.
Chris
induction loop and you have a metal bicycle (another reason to avoid
carbon fiber).
- Rare earth magnet (I am fond of expoying a pair in to the lugs of
your bike shoes, but many people use regular shoes)
- Lay the bike down in the middle of the induction loop (which is
alkward if loaded with stuff or in a busy intersection)
Some cities are starting to include bike specific sensors which
trigger lights in the United States, such as Portland, Seattle, and
Tucson, but not as many as one would hope and not as wide spread as
one would hope either. On occasion, using the Walk button, or
crosswalk is simply more practical.
Chris
M
Michael A. Terrell
Guest
Frank Krygowski wrote:
Most of the main roads around here are protected, but residential
roads aren't. Idiot traffic designers seem to be going through another
round of islands near intersections, and making shorter left turn
lanes. Just a few years ago, they were building center lanes for left
turns from either directions that were generally clear of traffic, and
available to emergency vehicles.
What they need is good video cameras, and impound the vehicles that
don't pull over to allow emergency vehicles through intersections. I
was in Ocala, Florida a few days ago, and saw an ambulance have to wait
to make a left turn, because the opposing traffic just kept rolling past
the entrance to the hospital.
US Hwy. 441 runs N/S through North Central Florida, and quite a bit is
separated four lane roadway, yet I rarely drive it without hearing a
siren.
--
http://improve-usenet.org/index.html
aioe.org, Goggle Groups, and Web TV users must request to be white
listed, or I will not see your messages.
If you have broadband, your ISP may have a NNTP news server included in
your account: http://www.usenettools.net/ISP.htm
There are two kinds of people on this earth:
The crazy, and the insane.
The first sign of insanity is denying that you're crazy.
Most of the main roads around here are protected, but residential
roads aren't. Idiot traffic designers seem to be going through another
round of islands near intersections, and making shorter left turn
lanes. Just a few years ago, they were building center lanes for left
turns from either directions that were generally clear of traffic, and
available to emergency vehicles.
What they need is good video cameras, and impound the vehicles that
don't pull over to allow emergency vehicles through intersections. I
was in Ocala, Florida a few days ago, and saw an ambulance have to wait
to make a left turn, because the opposing traffic just kept rolling past
the entrance to the hospital.
US Hwy. 441 runs N/S through North Central Florida, and quite a bit is
separated four lane roadway, yet I rarely drive it without hearing a
siren.
--
http://improve-usenet.org/index.html
aioe.org, Goggle Groups, and Web TV users must request to be white
listed, or I will not see your messages.
If you have broadband, your ISP may have a NNTP news server included in
your account: http://www.usenettools.net/ISP.htm
There are two kinds of people on this earth:
The crazy, and the insane.
The first sign of insanity is denying that you're crazy.