> Besides the point that a small pocket-IMU would be great. To GPS jumts > that big exist? As fas as i understand GPS it should have little jitter.
Trimble had a few GPS models out with dead reckoning. Not pocket sized. I think they are all off the market now. I got one off Ebay a few weeks ago but have not had time to set it up yet. To me it's more interesting reading the manuals and learning how it works since I don't use my car more than once a month. Trimble was addressing loss of signal in urban canyons not (ahem) antenna placement issues. See http://www.trimble.com/tms/placer450.aspx?dtID=overview They use a small gyroscope. There are much smaller gyros available now but my intuition from reading their materials is that it will work in a car if you are going fast enough (they want you to go 22 mph) to generate steady predictable g forces but if you are going at a walking pace it would never work. If you are walking around and want a reasonable position the Kalman filter would probably be easier to deal with. Is there a mathematician in the house? Brian _______________________________________________ Openmoko community mailing list community@lists.openmoko.org http://lists.openmoko.org/mailman/listinfo/community