Thread: Motorsport Performance Application - looking for developer to bring idea to reality
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lardman is offline lardman
2008-02-03 , 15:30
Posts: 2,102 | Thanked: 1,309 times | Joined on Sep 2006
#7
The problem for this is GPS accuracy. It just isn't good enough, and won't be soon. You'll certainly need 5Hz sampling, but the position errors will be a problem. GPS is only good to about 30 feet accuracy, and sometimes less. Reflected signals can cause much larger errors. There is survey-grade differential GPS available, but it's expensive and not very portable.
I disagree with you on this point (I think). Although GPS's absolute accuracy is not going to be enough (certainly with a single GPS and no additional DGPS information), which is why surveyors must use something more high-tech, we're talking about relative changes here.

For this, my understanding is that GPS not too inaccurate. Certainly there will be the standard problems with poor signal, but the more immediate problem is that you can probably only get data out at 1Hz (i.e. one reading per second). This will work for gross measurements, but for acceleration calculation you'll need a higher sampling rate, which means a more expensive GPS system that is able to output at higher frequency.