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Re: Dataloggers as aux timers? (was: '89 Nationals Timing Fiasco)

To: dg50@daimlerchrysler.com
Subject: Re: Dataloggers as aux timers? (was: '89 Nationals Timing Fiasco)
From: Byron Short <bshort@AFSinc.com>
Date: Fri, 01 Oct 1999 09:46:45 -0700
A datalogger file, GEEZ or otherwise, could easily be tweeked to shorter 
or longer times.  It wouldn't be too tough to write a program to run 
through the file and insert or delete additional readings.  So I 
wouldn't think that we'd want to accept a competitor's datalogger runs 
as any kind of proof of timing.  

What the datalogger *might* do is give you a heads up that something is 
wrong so that you can ask the officials to review their redundant 
system, or otherwise verify the legitimacy of their timing equipment.  
About the same as your spouse running a stopwatch on your 
time...completely unofficial, but perhaps useful as a first alert of a 
problem.

With that said, I think that now that the problems have been discovered 
and resolved (a la 1989) that this is mostly a dead horse.

--Byron

dg50@daimlerchrysler.com wrote:
> 
> Paul Foster <pfoster@gdi.net> wrote:
> 
> > This caused the times to be quite erratic and nonlinear. The best example 
>was
> > Chuck Sample - then a member of the SEB. His 3 runs varied by 8 seconds
> > although he swore that they should have been within a second of each
> > other. He protested and lost. But he was right. But he was also wrong
> > because there was nothing that could really be done about it...
> 
> So what if he had had a datalogger in the car (like the Edelbrock QwikData, 
>or a
> GEEZCube) that could have shown otherwise?
> 
> This is related to an issue that has come up in my datalogging adventures. 
>It's
> really very difficult to determine _exactly_ where a run starts or stops,
> especially on the typical Nationals course that has a tight turn before the
> start lights. (ProSolo is a little easier, the run starts when acceleration
> starts + reaction time)
> 
> I've been tossing around the idea of setting up one of those road race timing
> beacons at the start and finish lights, putting a sensor on the car, and 
>hooking
> it up to a channel in the datalogger. It then puts a mark in the data that
> corresponds to where the run starts and ends.
> 
> To help defer the cost of the beacons + tripods, I'd share. Throw a couple of
> bucks at me, I tell you the frequency, and from then on you get to use my
> beacons at every race I bring them to (and it saves having a huge cluster of
> beacons at the start/finish) Or maybe we convince the National Office to bring
> them around to every National Tour/ProSolo and make it part of their setup.
> 
> Or if everybody brings their own beacons, maybe we set them up to do segment
> times. :)
> 
> There are safety and performance issues to work through, but I'm pretty sure
> they could be solved. These beacons work across great big road race tracks;
> there's more than enough range in them to put the transmitter in a safe place.
> (Just gotta watch out for cross talk)
> 
> The nature of the receiver is simple enough that I'd bet GEEZ! customers could
> convince Byron to add a jack to the GEEZCube and the software changes to 
>support
> it.
> 
> Ok, so now I have a record of my run. It won't be _exactly_ the same as the
> official timers (for one, the beacon sensor needs to be placed as close as
> possible to the part of the car that actually breaks the timing beam, for the
> other, the beacon tends to be more of a "cone" than a "laser", so depending on
> how far away the tripod is from the actual finish, the part of the cone that
> trips the reciever may be a few feet away from the timing beam) but I would
> expect it to be close, and repeatable for each car (although not necessarily
> from car to car)
> 
> So if I get 4 runs, and the offical timing system records 50.100, 50.100,
> 50.100, 50.100, then I'd expect the logger to record something like 50.000,
> 50.000, 50.000, 50.000. Even something like 50.012, 50.023, 50.045, 50.032 
>would
> be OK - I'd accept a little noise, up to a tenth or two.
> 
> But let's say we're in Chuck's shoes. The logger says 50.012, 50.023, 50.045,
> 50.032, but the timer says 52.000, 54.000, 58.000, 56.000. Is that enough
> evidence to protest the results?
> 
> If so, where do you draw the line? Can I protest over .001 second's 
>difference?
> .050? .1? .5? 1?
> 
> Comments?
> 
> DG



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