How vehicle counters that time to time we see on the road wo

I'm sure you all see from time to time, some sort of device chained to a
pole with a pair of road-wide cable or hose like sensor.I'm not sure bot I
beleive they are vehicle counters (are they?) to collect data statistical
analysis of the traffic.

Do you know anything about them? If they are vehicle counters do you know
how they work? What they use as sensor? How accurate they are? Can they
distinguish different type of vehicles (caes, trucks etc) ? Can they detect
mutiple vehicles passing over their cabe/hose simultaneously ?

Thx.

 

[Caliban]

xyz wrote:

I'm sure you all see from time to time, some sort of device chained to a
pole with a pair of road-wide cable or hose like sensor.I'm not sure bot I
beleive they are vehicle counters (are they?) to collect data statistical
analysis of the traffic.

Do you know anything about them? If they are vehicle counters do you know
how they work? What they use as sensor? How accurate they are? Can they
distinguish different type of vehicles (caes, trucks etc) ? Can they detect
mutiple vehicles passing over their cabe/hose simultaneously ?

Thx.

I assume they work on a pneumatic to electric transducer (when the
hollow cable is squashed the pressure inside increases and a count is
produced). The count would be referenced to a clock to determine the
volume of traffic v's time of day. This data could then be used to plan
works involving disruption to traffic flow, and aid in road planning.

I'd be interested in knowing if the versions with two cables spaced a
short distance apart are be able to determine direction as well as
volume of traffic (which sensor fires first), and possibly wheelbase
length and speed (time for front wheels to cross both sensors combined
with time for back wheels to cross both sensors). I've never seen these
types extend across more than one lane.

 

[Dingo]

I assume the cable is a switch that gets switched when a heavy enough load
"squeezes" the cable enough.

I'd imagine once a vehicle passes over it it has a timer of something like 1
second before it will register another car. This way the back tyres are not
counted as another car, or a semi-trailer as serveral cars.

Just my guess.


<xyz> wrote in message news:41df6e4f$0$5058$afc38c87@news.optusnet.com.au...

I'm sure you all see from time to time, some sort of device chained to a
pole with a pair of road-wide cable or hose like sensor.I'm not sure bot I
beleive they are vehicle counters (are they?) to collect data statistical
analysis of the traffic.

Do you know anything about them? If they are vehicle counters do you know
how they work? What they use as sensor? How accurate they are? Can they
distinguish different type of vehicles (caes, trucks etc) ? Can they
detect
mutiple vehicles passing over their cabe/hose simultaneously ?

Thx.

 

[John Tserkezis]

xyz wrote:

Do you know anything about them?

Only had a play with the very old versions.

If they are vehicle counters do you know how they work?

The ond one I had seen (a long time ago) was a pneumatic air pressures sensor
that sensed quick air pressure changes. The pulses were divided by two, then
that passed onto a mechanical counter.

What they use as sensor?

Geeze I'm a hoard. I still have the sensor.

A StreeterAmet "Electronic Air Switch" from Measurement Systems Division.

A cylindrical object about 40mm in diameter, with a piezo disk on one side,
with three screw mount connectors on the other. Two for power, one for output.
It outputs one short pulse per air pulse that comes in. The other side is
mounted via hoses and such to the rubber hose that runs along the width of the
street.

How accurate they are?

With this model, since it is fixed to divide by two, reliability with cars
would be excellent. Once you get trucks and such, it would throw the averages out.

Can they distinguish different type of vehicles (caes, trucks etc)?

This one can't,

Can they detect mutiple vehicles passing over their cabe/hose simultaneously?

I don't think any system would be able to tell, however:

From what I've observed more recently, there can be two tubes across two lane
roads (with one tube only the width of one lane), that way, there is more
accurate counting even with multiple simultaineous vehicles on both lanes.

As far as potential goes, two tubes spaced by a short distance, it could also
give speed estimates.

If you do away with rubber hoses, and use innductive loops, you can also
indicate moving/stalled traffic.

If they use a micro (which nowadays they would most likely), you can log
traffic density at different times of day, with careful timing, they could
count cars AND trucks (assuming a minimum time between vehicles), approx speed
of those vehicles at those times, and whether or not the traffic was part of a
parking lot or the traffic was moving.

--
Linux Registered User # 302622 <http://counter.li.org>

 

[Richard]

As far as I know, they use a pressure transducer to give some idea of
vehicle weight, ie bigger tyre - more pressure.

Single strip measures counts only.

Double strip senses counts, speed and direction. Every time you speed over
one of these, the statistics gathered go in the favour of lowering speed
limits.

Software is used to determine (to some degree) the type of vehicle from the
raw data gathered.

That's the limit of my knowledge. Perhaps someone who works for a traffic
authority (ie Main Roads Perth) can shed more light.

Had one in front of our house a few months ago. The first night some vandals
cut the tubes. (Mindless idiots!) A week later the device was set up again
and survived. The nuisance was the noise as vehicles passed over at all
hours of the night! And the fact that tax payers' money was wasted in
repairs and the whole excercise of data gathering had to be repeated.

Richard.

"John Tserkezis" <jt@techniciansyndrome.org.invalid> wrote in message
news:41df8e62$0$3788$afc38c87@news.optusnet.com.au...

xyz wrote:

Do you know anything about them?

Only had a play with the very old versions.

If they are vehicle counters do you know how they work?

The ond one I had seen (a long time ago) was a pneumatic air pressures
sensor that sensed quick air pressure changes. The pulses were divided by
two, then that passed onto a mechanical counter.

What they use as sensor?

Geeze I'm a hoard. I still have the sensor.

A StreeterAmet "Electronic Air Switch" from Measurement Systems Division.

A cylindrical object about 40mm in diameter, with a piezo disk on one
side, with three screw mount connectors on the other. Two for power, one
for output. It outputs one short pulse per air pulse that comes in. The
other side is mounted via hoses and such to the rubber hose that runs
along the width of the street.

How accurate they are?

With this model, since it is fixed to divide by two, reliability with
cars would be excellent. Once you get trucks and such, it would throw the
averages out.

Can they distinguish different type of vehicles (caes, trucks etc)?

This one can't,

Can they detect mutiple vehicles passing over their cabe/hose
simultaneously?

I don't think any system would be able to tell, however:

From what I've observed more recently, there can be two tubes across two
lane roads (with one tube only the width of one lane), that way, there is
more accurate counting even with multiple simultaineous vehicles on both
lanes.

As far as potential goes, two tubes spaced by a short distance, it could
also give speed estimates.

If you do away with rubber hoses, and use innductive loops, you can also
indicate moving/stalled traffic.

If they use a micro (which nowadays they would most likely), you can log
traffic density at different times of day, with careful timing, they could
count cars AND trucks (assuming a minimum time between vehicles), approx
speed of those vehicles at those times, and whether or not the traffic was
part of a parking lot or the traffic was moving.

--
Linux Registered User # 302622
http://counter.li.org

 

[David Sauer]

On Sat, 8 Jan 2005 16:12:33 +0800, "Richard" <rkabz@ellenbrook.net>
wrote:

Had one in front of our house a few months ago. The first night some vandals
cut the tubes. (Mindless idiots!) A week later the device was set up again
and survived. The nuisance was the noise as vehicles passed over at all
hours of the night! And the fact that tax payers' money was wasted in
repairs and the whole excercise of data gathering had to be repeated.

They're used privately too.

Had one outside a shopping centre being constructed. A few weeks later
they had some advertising up about how xyz number of cars pass by this
site.

 

[Rod Out back]

"John Tserkezis" <jt@techniciansyndrome.org.invalid> wrote in message
news:41df8e62$0$3788$afc38c87@news.optusnet.com.au...

xyz wrote:

Do you know anything about them?

Only had a play with the very old versions.

If they are vehicle counters do you know how they work?

The ond one I had seen (a long time ago) was a pneumatic air pressures
sensor
that sensed quick air pressure changes. The pulses were divided by two,
then
that passed onto a mechanical counter.

What they use as sensor?

Geeze I'm a hoard. I still have the sensor.

A StreeterAmet "Electronic Air Switch" from Measurement Systems
Division.

A cylindrical object about 40mm in diameter, with a piezo disk on one
side,
with three screw mount connectors on the other. Two for power, one for
output.
It outputs one short pulse per air pulse that comes in. The other side
is
mounted via hoses and such to the rubber hose that runs along the width of
the
street.

How accurate they are?

With this model, since it is fixed to divide by two, reliability with
cars
would be excellent. Once you get trucks and such, it would throw the
averages out.

Can they distinguish different type of vehicles (caes, trucks etc)?

This one can't,

Can they detect mutiple vehicles passing over their cabe/hose
simultaneously?

I don't think any system would be able to tell, however:

From what I've observed more recently, there can be two tubes across two
lane
roads (with one tube only the width of one lane), that way, there is more
accurate counting even with multiple simultaineous vehicles on both lanes.

As far as potential goes, two tubes spaced by a short distance, it could
also
give speed estimates.

If you do away with rubber hoses, and use innductive loops, you can also
indicate moving/stalled traffic.

If they use a micro (which nowadays they would most likely), you can log
traffic density at different times of day, with careful timing, they could
count cars AND trucks (assuming a minimum time between vehicles), approx
speed
of those vehicles at those times, and whether or not the traffic was part
of a
parking lot or the traffic was moving.

--
Linux Registered User # 302622
http://counter.li.org

A few years ago, the local council put one on the single-lane bitumen road
through the creek channels near our homestead (shire road). We encouraged
them to put it elsewhere, as the wet season was looming, and their location
was right in the middle of the flood zone. However, they didnt listen to
mere mortals...It was one of the old pneumatic tube systems, and I see they
still use the same to date(they work and are easy to relocate).

A fresh-faced young council official turns up after the creeks have been
flooding for a fortnight, and now receeded. He asked if we had been and
checked the counter recently (they had kindly left us a key to the box), and
if there had been much traffic recorded. It was worthwhile to see his face
when we told him it had switched from cars per day to litres per minute when
the flood got to it a fortnight ago...

They apparently found a freshwater crab residing in it when the box was
opened. It tried to bite the council official...

Cheers,

Rod.......Out Back

 

[Martin]

"Rod Out back" <someone@IHATESPAM.BIGPOND.COM> wrote in message
news:9GNDd.109862$K7.33289@news-server.bigpond.net.au...
[SNIP]

A few years ago, the local council put one on the single-lane bitumen road
through the creek channels near our homestead (shire road). We encouraged
them to put it elsewhere, as the wet season was looming, and their
location
was right in the middle of the flood zone. However, they didnt listen to
mere mortals...It was one of the old pneumatic tube systems, and I see
they
still use the same to date(they work and are easy to relocate).

A fresh-faced young council official turns up after the creeks have been
flooding for a fortnight, and now receeded. He asked if we had been and
checked the counter recently (they had kindly left us a key to the box),
and
if there had been much traffic recorded. It was worthwhile to see his
face
when we told him it had switched from cars per day to litres per minute
when
the flood got to it a fortnight ago...

They apparently found a freshwater crab residing in it when the box was
opened. It tried to bite the council official...

Cheers,

Rod.......Out Back

ROFLMAO!!!!!!!!!!!

What a classic!!!

 

[Dingo]

Snap Snap - Take that useless council!

I wish a Fresh Water Crab would crawl into the envolope I pay my rates in


"Martin" <invalid.vk2umj@invalid.yahoo.com.au> wrote in message
news:349sukF477ni8U1@individual.net...

"Rod Out back" <someone@IHATESPAM.BIGPOND.COM> wrote in message
news:9GNDd.109862$K7.33289@news-server.bigpond.net.au...
[SNIP]

A few years ago, the local council put one on the single-lane bitumen
road
through the creek channels near our homestead (shire road). We
encouraged
them to put it elsewhere, as the wet season was looming, and their
location
was right in the middle of the flood zone. However, they didnt listen to
mere mortals...It was one of the old pneumatic tube systems, and I see
they
still use the same to date(they work and are easy to relocate).

A fresh-faced young council official turns up after the creeks have been
flooding for a fortnight, and now receeded. He asked if we had been and
checked the counter recently (they had kindly left us a key to the box),
and
if there had been much traffic recorded. It was worthwhile to see his
face
when we told him it had switched from cars per day to litres per minute
when
the flood got to it a fortnight ago...

They apparently found a freshwater crab residing in it when the box was
opened. It tried to bite the council official...

Cheers,

Rod.......Out Back

ROFLMAO!!!!!!!!!!!

What a classic!!!

 

[Albm&ctd]

On Sat, 8 Jan 2005 16:12:33 +0800, "Richard" <rkabz@ellenbrook.net>
wrote:

As far as I know, they use a pressure transducer to give some idea of
vehicle weight, ie bigger tyre - more pressure.

Single strip measures counts only.

Double strip senses counts, speed and direction. Every time you speed over
one of these, the statistics gathered go in the favour of lowering speed
limits.

On the contrary. If the number of cars passing are not doing anywhere

near the speed limit that gives the sloths an indication that the
current limit is too high.
I suspect in this area a number of sneaky placements (for instance
after roadwork signs) have resulted in false data (or collected data
that reflected the wanted outcome) as justification to lower speed
limits from 80 km/h to 60 km/h in some cases.
From a GovCO letter dated 27/10/2004 in reply to my concerns about
speed limit lowering in this area it states, with regard to
'appropriate speed limit for a particular road':

* pavement, shoulder and lane width
* horizontal and vertical road alignment
* traffic volume, activity and prevailing speeds

And there are six more criteria but all of these conditions have been
improved or remain unchanged on the roads in question but they remain
20 km/h under the old long standing limit. I suspect false data
gathering but it's hard to prove. Returning to the third 'prevailing
speeds' is mentioned. If the pneumatic counting and speed measuring
device is installed in a location where they have placed signs
requiring you to travel slower due to roadwork or they are placed just
after the roadwork then they are, to my mind, gathering false data to
lower limits.

Al

I don't take sides. It's more fun to insult everyone.
http://kwakakid.cjb.net/insult.html

 

[MC]

xyz wrote:

I'm sure you all see from time to time, some sort of device chained to a
pole with a pair of road-wide cable or hose like sensor.I'm not sure bot I
beleive they are vehicle counters (are they?) to collect data statistical
analysis of the traffic.

Do you know anything about them? If they are vehicle counters do you know
how they work? What they use as sensor? How accurate they are? Can they
distinguish different type of vehicles (caes, trucks etc) ? Can they detect
mutiple vehicles passing over their cabe/hose simultaneously ?

Thx.

Phenumatic tubes are still commonly used. (they're cheap and portable).
In-road inductive-loops are much more expensive to install.

With more that one detector (loop or tube) you can detect speed,
direction and class of vehicle. (there are about 12 officially used
vehicle 'types' (eg. sedan, motor bike, truck(s),
trucks with trailers, ... )

They cannot be 100% accurate in classifing traffic because
inter-vehicle spacing varies with speed and road conditions,
and there are combinations of numbers of axles and axle-spacings
which can produce ambiguous or nonsensical classifications.

 

[David L. Jones]

John Tserkezis wrote:

If they use a micro (which nowadays they would most likely), you can
log
traffic density at different times of day, with careful timing, they
could
count cars AND trucks (assuming a minimum time between vehicles),
approx speed
of those vehicles at those times, and whether or not the traffic was
part of a
parking lot or the traffic was moving.

Bill Gates and Paul Allen designed a micro controlled traffic analysis
machine way back in mid-70's before Microsoft, and tried to flog it
under their Traf-O-Data business. It might very well have been the
first intelligent controlled traffic analysis counter. I think it used
an 8008 micro. Scary.

Dave