On Thu, 12 May 2005, Dave Arquati wrote:

Stuart wrote:
Vernon wrote:

When LBC Travel News talk of travel information derived from
"Satellite Data", what sort of satellite help are they getting? I am
aware of GPS for navigation, but I can't see how that could help with
determining the levels of realtime traffic problems.

Just curious, but does anyone here know?

Years ago they used to have 'real time travel data' which was linked
to the Trafficmaster system. This monitored the speed of individual
cars from point A to point B (while making the actual registration
number anonomous) to give a journey time.

Don't TfL do this with the congestion charge cameras too, i.e. measure
the journey times of individual cars between two cameras to get traffic
information for particular links?

I always thought that these traffic-monitoring systems should be
integrated somewhat with the London Buses data. At the moment, the
London Buses realtime information is not particularly realtime, and
generally only talks about roadworks, scheduled diversions and scheduled
disruptive events like demonstrations. I'd like to know how congested a
given link is, so I can plan my bus journey to avoid it, or use the Tube
instead.

A very impressive system would be to not only have accurate Countdown
information online and at stops, but also to have dynamically-estimated
journey times to destinations from that stop, available both online and
via Countdown at the stop itself. Integrate this into Journey Planner
for those looking for journeys departing "now", and you get an extremely
accurate guide as to the quickest way to your destination.

This is what we call a 'pipe dream' . Yes, this would be very cool, but
the amount of effort it would require to gather the traffic data, process
it to produce congestion forecasts (not entirely unlike weather
forecasting - congestion is a dynamic, nonlinear, mobile phenomenon), work
out delays to services and distribute this to every bus-stop would be
substantial.

Integrating into the online planner would also, i imagine, be very
difficult - it's the sort of thing that sounds easy, but is often
fiendishly difficult in practice, since the planner software will be built
around the assumption of a static database, rather than one which changes
every minute.

How would countdown display the delay information? There are dozens of
destinations for each bus; would it go through all of them? Key stops?
Stops affected by delays?

Anyway, having said all that, this is a good idea, and i'd imagine bits of
it will be implemented in the future.

tom

--
Gotta treat 'em mean to make 'em scream.