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(meteorobs) What is the ideal design...

As I posted earlier, I am building equipment for large-group visual
observations of the Leonid shower this November. My intention is to get a
ton of visual data that can become the basis for a number of statistical
studies. For example, with that many observers, we can really nail down
coefficients of perception and (even) variances in coefficients of
perception. We can also get precise timings of meteors. To this end, the
equipment I have designed consists of three main parts:

1) a set of pushbuttons, one for each observer. Each pushbutton unit has a
green LED to indicate that it is on-line and a beeper that activates
whenever the button is pushed. The buttons plug into standard RJ-11
telephone cables.

2) a box with a BASIC STAMP 2 computer and a bunch of sockets for telephone
cables. This little computer monitors the pushbuttons. It can tell when an
observer plugs in (indicating that the observer is now on-line) and unplugs
(indicating that he is off-line). It logs all button presses and reports
them to 

3) a Mac PowerBook that compiles and stores the main log.

This equipment was built two years ago, and although I disassembled the
BASIC STAMP 2 box after the 1999 shower, it will be no problem to reassemble
it. 

The issue I want to place before this group is, "what improvements could be
made to this arrangement?"

One obvious improvement would be inclusion of magnitude data. This could be
done with multiple buttons, but I am concerned that it will impose a
cognitive load on the observer that will significantly affect the
coefficient of perception, especially at high rates. In 1999, we found that
observers could just barely keep up with an observed rate of 4,000 per hour.
With this year's rate peaking at 2,000 per hour, I worry that observers
won't be able to keep up when they have the extra load of figuring
magnitudes. 

I have thought up several schemes to handle this. One is a variable-depth
switch coupled with audio feedback. You give it a quick tap for magnitude 5
or fainter, a double-click depth for mag 4, three-click depth for mag 3, and
so forth. As you do this, you hear a tone in your earpiece that rises in
frequency with each magnitude step. The hope is that observers will quickly
train to the system and be able to enter lots of accurate data under time
pressure.

Another approach is to have a button for each of the three main fingers on
each of two hands. The brighter the meteor is, the more buttons you hold
down. This has all sorts of technical problems with buttons going down
unsimultaneously.

A third approach is voice recognition. Conventional voice recognition
systems are a bit too slow to handle the highest rates, but I'm thinking of
implementing something based on vocalizing vowels, which are, in terms of
audio, much simpler than consonants. We could even do with simple throat
mikes. However, it would impose severe discipline on the observers: no
exclamations or any kind of speaking while observing!

These are some of my preliminary ideas on the problem. There's also the
matter of building something simple enough that other people could duplicate
it; that argues against the vowel recognition system.

What do the members of this group think of these various options?

Chris Crawford 
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