Re: Passenger Information Displays

[G.Lambert@unsw.edu.au (Geoff Lambert)]

Alex Borodin <alex.borodin@qrail.com.au> wrote:

>Hi,

>Just wondering what sort of thoughts ya'll have about 
>Passenger Information Displays, especially the Outdoor LED type
>displays like they have in Sydney, Melbourne and Perth.


>I want to hear all of your gripes, complaints, suggestions,
>comments, and kudos about all the different PIDS LED signs
>you've ever come in contact with.

It is worth thinking about colour and catering for colour-vision
impaired people- a significant proportion of the population.  The old
style train indicators on the City Circle in Sydney, which had a white
indicator light beside each station name to indicate that a train
stopped there, were haphazardly replaced some years ago by newer
versions that had a red light instead.  A railfan friend of mine said
that, for him, the lights effectively disappeared and could not be
distinguished from positions that had the light extinguished.

Two other points worth thinking about, especially for determining the
stopping pattern

* Apart from the colour problem (above), the system used on many City
Circle indicator boards seems to work quite well.  Once one knows the
general layout of the boards at one's stations, it is easy to see at a
single glance, whether the next train has your desired stopping
pattern.  There's no need to actually read the station names beside
the lights at all.  I would reckon the time for pattern recognition is
much shorter this way.  There are a couple of problems, though.
First, to accomodate all the station names, the signs must be rather
large, especially in the vertical direction- you need a high ceiling
to hang them from.  Second, being linear in nature, they are not
really very suited to a complex network that has many nodes and
alternative routes.  Which leads me to the suggestion (I don't know
whether anyone has tried it) to make an equivalent sign, but one in
which the linear strip of names is substituted by the system map, with
lights lighting up at the stations that are to be called at- rather
like an illuminated track diagram in reverse.  For trains travelling
on circular routes, some form of directional indicator would be a
useful adjunct.

*  I have always been imprerssed by the amazing LCD displays they have
at Spencer St, they must be the biggest LCD displays in the world....
each "letter" box is the size, shape and appearance of a ceramic tile.
Of course, they require an external light source (but they work well
in daylight (?), but being black and white, they obviate the colour
vision problem.

Geoff Lambert