I’m looking for a GPS with very good positional accuracy. This will be used to plot position in a racecar. It needs to be at least 10hz also. Any suggestions?
Justin
In No. America, with a WAAS capable GPS, and if you are where you can receive WAAS from the geosynchronous satellites. They are low in the sky, according to your location and the angle to the equatorial plane.
With WAAS, you can expect about 5m RMS if you place the GPS antenna such that the GDOP error is small (wide sky view, no terrain)
If you cannot receive WAAS, then you’ll need other correction data (DGPS) and there are lots of ways to get that and send it to your on-car GPS receiver.
As to 10Hz, these are $$$$; I’ve seen some relatively low cost 5Hz receivers.
I may have to live with 5hz. However, it seems like most of the 5hz models with good positional accuracy (<2.5m) are QFN. I haven’t seen any modules… just IC’s.
The only 10hz one that I can find is the Atmel ATR0625, which claims <2.0m accuracy. However, it’s QFN56, and it doesn’t look easy to interface with. Not to mention minimum quantities are around 2000.
I found a bluetooth receiver based on that chipset… I’m tempted to try to reverse engineer it.
Hmm.
Regarding positional accuracy… will each reading be off by the same amount, or could any reading by off by 2-5m?
If all readings within a reasonable time period are off by the same amount, then I could care less!
Justin, you can start with a complete 5Hz module with serial (ttl level) output, like the EB85 or the LS20031 http://www.sparkfun.com/commerce/produc … ts_id=8975
I used a EB85 last year on my bike, connected to a Logomatic. It is fun but after several session, I discovered it is not so usefull for trajectory analysis. It is more usefull to analize speed, chassis or motor data acquistion related to track position.
Angelo