I have no idea what they're called, the LED signs in some bus stops
that tell you how long the busses are supposed to be, my question is,
how do they work? how do they update?

A few times I've seen that my bus is due next in a couple of minutes
but it just doesn't arrive, several later busses come and then it
vanishes off the sign, abducted by aliens?

Then there are the times I've seen my bus is due in 10 minutes and
decided that instead of standing in the cold I'll walk to the next or
previous stop only for it to come sailing past when I'm mid-way
between stops.

And how many seconds are in a London Transport minute anyway? 90 at
least.

Obviously the system is not perfect (no system is) but if I knew what
made it tick I may be better equipped for getting around.

And why I'm grumbling about busses, why is it so rare for a 38 to get
to the end of it's route? I live near clapton pond and often need to
travel to victoria, when I have the time I'd rather sit on a bus than
go underground but often they terminate at hyde park corner or green
park, same the other way often only making it to hackney central, in
both cases I need to get another bus, pain in the arse, especially as
the end of their route is only 5 minutes away.

grumble grumble
--
Mark.
www.MarkVarleyPhoto.co.uk
www.TwistedPhotography.co.uk
www.TwistedArts.co.uk
www.FacelessLadies.com
www.BeautifulBondage.net

On 11 Apr, 17:20, MarkVarley - MVP
wrote:

I have no idea what they're called, the LED signs in some bus stops
that tell you how long the busses are supposed to be, my question is,
how do they work? how do they update?

A few times I've seen that my bus is due next in a couple of minutes
but it just doesn't arrive, several later busses come and then it
vanishes off the sign, abducted by aliens?

Then there are the times I've seen my bus is due in 10 minutes and
decided that instead of standing in the cold I'll walk to the next or
previous stop only for it to come sailing past when I'm mid-way
between stops.

And how many seconds are in a London Transport minute anyway? 90 at
least.

Obviously the system is not perfect (no system is) but if I knew what
made it tick I may be better equipped for getting around.


The system is called Countdown, and as part of the iBus project it is
set to become much more reliable and accurate.

Countdown:
http://www.tfl.gov.uk/corporate/proj...ment/2369.aspx
or via http://tinyurl.com/4swhsj

iBus:
http://www.tfl.gov.uk/corporate/proj...ment/2373.aspx
or via http://tinyurl.com/yu6wwe

In message , MarkVarley -
MVP writes

I have no idea what they're called, the LED signs in some bus stops
that tell you how long the busses are supposed to be, my question is,
how do they work? how do they update?

The current system, called Countdown, is fairly primitive. When a bus
passes a fixed point (with a large bar-code) earlier along the route,
the system simply adds the standard time it takes to get from that fixed
point to the bus stop at which you are waiting. If the bus subsequently
gets delayed, it knows nothing about it. Equally, if the bus is diverted
or is too far from the curbside to trigger the reader, or if it is
overtaking another bus (or any large vehicle) as it passes the bar-code,
the system know nothing about it.

The Countdown system is currently being replaced by a rather better,
GPS-based system.
--
Paul Terry

On Apr 11, 5:48*pm, Mizter T wrote:
On 11 Apr, 17:20, MarkVarley - MVP
wrote:





I have no idea what they're called, the LED signs in some bus stops
that tell you how long the busses are supposed to be, my question is,
how do they work? how do they update?

A few times I've seen that my bus is due next in a couple of minutes
but it just doesn't arrive, several later busses come and then it
vanishes off the sign, abducted by aliens?

Then there are the times I've seen my bus is due in 10 minutes and
decided that instead of standing in the cold I'll walk to the next or
previous stop only for it to come sailing past when I'm mid-way
between stops.

And how many seconds are in a London Transport minute anyway? 90 at
least.

Obviously the system is not perfect (no system is) but if I knew what
made it tick I may be better equipped for getting around.

The system is called Countdown, and as part of the iBus project it is
set to become much more reliable and accurate.

Countdown:http://www.tfl.gov.uk/corporate/proj...nologyandequip...
or via http://tinyurl.com/4swhsj

iBus:http://www.tfl.gov.uk/corporate/proj...nologyandequip....
or via http://tinyurl.com/yu6wwe-

I wonder if it means more reliable in terms of whether it breaks down
or reliable in terms of the content, which must be down to where the
locations of the bus-detectors rather than the system that passes
information to the punters.

I suspect that the information is very accurate, but that it doesn't
necessarily relate to the location of the bus stop.

That is, some stops will display information about buses that have
already gone past (and therefore seem to disappear) and others
disappear the information off long before the bus has turned up.

I also recall a problem with a bus whose starting point was just round
the corner, and it turned up unannounced because the system didn't
seem to be aware of it at all (a nice surprise in that case).

On Fri, 11 Apr 2008, Mizter T wrote:

On 11 Apr, 17:20, MarkVarley - MVP
wrote:

I have no idea what they're called, the LED signs in some bus stops
that tell you how long the busses are supposed to be, my question is,
how do they work? how do they update?

The system is called Countdown, and as part of the iBus project it is
set to become much more reliable and accurate.

Which is a roundabout way of saying that the present system is not very
reliable or accurate :P.

As another poster pointed out, the present system is rather Heath-Robinson
and failure-prone. It was, though, the best that could be done with the
technology of the time it was implemented. Frustrating as it is, it's
better than nothing.

tom

--
Ed editor textorum probatissimus est -- Cicero, De officiis IV.7

On Fri, 11 Apr 2008, MIG wrote:

On Apr 11, 5:48*pm, Mizter T wrote:
On 11 Apr, 17:20, MarkVarley - MVP
wrote:

I have no idea what they're called, the LED signs in some bus stops
that tell you how long the busses are supposed to be, my question is,
how do they work? how do they update?

The system is called Countdown, and as part of the iBus project it is
set to become much more reliable and accurate.

I wonder if it means more reliable in terms of whether it breaks down
or reliable in terms of the content, which must be down to where the
locations of the bus-detectors rather than the system that passes
information to the punters.

The new system won't use bus detectors, it'll have a GPS unit on each bus
which radios its position back to base (by GPRS?). That gives it higher
resolution, and makes it impossible for a bus to fall off the system, as
they can now.

Provided that the bus can get good GPS and GPRS signals. GPS is
notoriously inaccurate in built-up areas, as buildings block lines of
sight to the satellites, and introduce reflections which confuse the
receiver (like ghosting on the telly). I wonder what they're doing to deal
with this? Maybe just having the receiver on the top of the bus will be
enough. Newer GPS chipsets are also getting better at operating in urban
environments - for instance, i hear that the SirfStar III is much better
than older kit:

http://wiki.openstreetmap.org/index.php/SiRF_III

I suspect that the information is very accurate, but that it doesn't
necessarily relate to the location of the bus stop.

That is, some stops will display information about buses that have
already gone past (and therefore seem to disappear) and others
disappear the information off long before the bus has turned up.

Neither of those should happen. The main failure mode will probably be the
display (or its communication link) breaking down altogether.

Another plus of iBus is that it will let the bus operators and TfL track
all buses all the time, which will give them a much, much better ability
to (a) regulate the service and (b) monitor performance. Operators will
find it much harder to get away with providing a substandard service,
particularly at night, when i understand tfL's inspectors don't operate.

tom

--
Ed editor textorum probatissimus est -- Cicero, De officiis IV.7

On Apr 11, 7:04*pm, Tom Anderson wrote:
On Fri, 11 Apr 2008, MIG wrote:
On Apr 11, 5:48*pm, Mizter T wrote:
On 11 Apr, 17:20, MarkVarley - MVP
wrote:

I have no idea what they're called, the LED signs in some bus stops
that tell you how long the busses are supposed to be, my question is,
how do they work? how do they update?

The system is called Countdown, and as part of the iBus project it is
set to become much more reliable and accurate.

I wonder if it means more reliable in terms of whether it breaks down
or reliable in terms of the content, which must be down to where the
locations of the bus-detectors rather than the system that passes
information to the punters.

The new system won't use bus detectors, it'll have a GPS unit on each bus
which radios its position back to base (by GPRS?). That gives it higher
resolution, and makes it impossible for a bus to fall off the system, as
they can now.

Ah right. That should definitely be an improvement, as long as the
right direction has been programmed in ...

Does the use of GPS have implications for Oyster and flat fares?

On Apr 11, 6:52*pm, Tom Anderson wrote:
On Fri, 11 Apr 2008, Mizter T wrote:
On 11 Apr, 17:20, MarkVarley - MVP
wrote:

I have no idea what they're called, the LED signs in some bus stops
that tell you how long the busses are supposed to be, my question is,
how do they work? how do they update?

The system is called Countdown, and as part of the iBus project it is
set to become much more reliable and accurate.

Which is a roundabout way of saying that the present system is not very
reliable or accurate :P.

As another poster pointed out, the present system is rather Heath-Robinson
and failure-prone. It was, though, the best that could be done with the
technology of the time it was implemented. Frustrating as it is, it's
better than nothing.

Was it a development of the BESI system used in the 1970s?

On 11 Apr, 18:52, Tom Anderson wrote:

On Fri, 11 Apr 2008, Mizter T wrote:

On 11 Apr, 17:20, MarkVarley - MVP
wrote:

I have no idea what they're called, the LED signs in some bus stops
that tell you how long the busses are supposed to be, my question is,
how do they work? how do they update?

The system is called Countdown, and as part of the iBus project it is
set to become much more reliable and accurate.

Which is a roundabout way of saying that the present system is not very
reliable or accurate :P.

As another poster pointed out, the present system is rather Heath-Robinson
and failure-prone. It was, though, the best that could be done with the
technology of the time it was implemented. Frustrating as it is, it's
better than nothing.


Heath Robinson-esque is quite the right sounding description! I
couldn't quite remember when Countdown began, but after a bit of
googling I found this post by the great Mr Arquati, formerly (and I
still think occasionally) of this parish...

http://groups.google.co.uk/group/uk....6435d488fdeb6a

....in which it is stated that the Countdown system went live in 1996
(the above thread incidentally is from 2005 and concerns the Countdown/
iBus overhaul), when GPS technologies were pricey and the government
hardly splashed LT with cash.

I don't know the plotted history of the system but I wouldn't be at
all surprised to learn that it was only installed on a few routes at
first.

Anyway, 'tis a grand thing that it will be made better. It's most
frustrating to have to guess whether the display is telling the truth
or not.

On 11 Apr, 19:04, Tom Anderson wrote:
Provided that the bus can get good GPS and GPRS signals. GPS is
notoriously inaccurate in built-up areas, as buildings block lines of
sight to the satellites, and introduce reflections which confuse the
receiver (like ghosting on the telly). I wonder what they're doing to deal
with this?

I've read a TfL paper that I can't find right now that found it to be
surprisingly accurate, something like dead on 98% of the time.
Presumably to do with being aerial mounting a large antenna on the bus
roof where it has a good view of the sky, rather than the tiny
internal one in consumer gear that gets blocked by the car roof.

Is there a way to tell if a bus is using iBus data or Countdown. Have
any iBus-based displays even been deployed yet?

U

--
http://londonconnections.blogspot.com/
A blog about transport projects in London