Ronnie wrote:Hi Harry,
If we utilize the "VBOX Sport 20 Hz GPS" or "XGPS160" will the accelerometer shown on the overlay use the info from these external GPS.
Also do we need to copy the data over to the phone or it will automatically be available when we overlay the data. Thanks
VBOX and XGPS deliver GPS, no acceleration data. It is possible to derive acceleration data from GPS but this should be a fallback for situation measuring fails only. LapTimer includes some "acceleration from GPS" feature available in Lap Details / Recalculate. This calculation dates back to PalmOS times when accelerometers have not been included in smartphones. It work reasonable for 1 Hz data but adds a lot of noise for higher update rates. Good "acceleration from GPS" calculations use a similar approach like LapTimer's but add some kind of smoothing algorithms on top.
Nevertheless, once you have high GPS update rates, LapTimer stores acceleration at this rate too, so the acceleration display gets a lot more responsive.