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Yaw rate data

Posted: Tue Jun 18, 2013 1:59 pm
by gplracerx
I see that there is a yaw rate plot available now in the app. Would you please add that data to the .csv file. I'm assuming from the relative lack of noise that the data is coming from the internal rotation rate 'gyro' in the device rather than being the derivative of the gps heading data.

Re: Yaw rate data

Posted: Tue Jun 18, 2013 3:05 pm
by Harry
The yaw rate is calculated from GPS and averaged. I ran lots of tests on the filter applied to get acceptable results for the different receiver update rates. It works for high update frequencies (5 Hz and above) only.

- Harry

Re: Yaw rate data

Posted: Tue Jun 18, 2013 4:20 pm
by gplracerx
Doesn't the iOS Core Motion package allow you to get yaw rate from the device directly? Then you don't need high data rate GPS. Speaking of which, I'm still waiting to hear from Racelogic about my VBox Sport.

Re: Yaw rate data

Posted: Tue Jun 18, 2013 4:21 pm
by Harry
As you know LapTimer does not currently use Core Motion ;-)

- Harry

Re: Yaw rate data

Posted: Tue Jun 18, 2013 10:02 pm
by gplracerx
You don't actually need Core Motion. The accelerometer calibration should give you all the data you need to transform the rotation axes too, since they're coaxial with the accelerometer axes, or close enough anyway..