Harry's GPS Suite Forum

Great stuff Harry.

I was able to successfully record laps while at Barber in Alabama for an entire morning. However, during lunch I removed the external GPS and phone from the bike to charge and review the data. The very first session after lunch no laps were recorded. I seem to recall that it kept asking me about changing the orientation of the phone (since i handled it while removing and replacing on the bike) and that the calibration had to be redone. I locked the display rotation and went for another session, still no laps recorded. I reloaded the track, and still no laps. Unfortunately the entire afternoon had nothing recorded at all. What should i check before setting off onto the track to ensure that the laps WILL be recorded?

Also, i notice that the external GPS is collecting data "@ 1.0 Hz". I was expecting 5 Hz with my XGPS150, what determines that update rate? THe reason I ask is that since the motorcycle does not produce any lateral acceleration as measured by the iPhone (because the lateral acceleration component should be measured through the perpendicular axis of the phone, not the lateral/sideways one as is the case with a car), i must rely on the 'recalculation' feature for each lap so that HLT calculates my lateral g's correctly based on GPS and that resolution is compromised by the slow update rate.

Thanks Harry, and you'll be happy to know that I sold 3 more HLT licenses since that weekend while showing it off!

regards
George

Hi George,

The items to be checked are discussed in viewtopic.php?f=8&t=2 It is mainly about making sure GPS is o.k. (i.e. update rate >= 1 Hz and "green" accuracy), and a valid - and conflict free- track set loaded. As the later has not been changed from my understanding, it seems GPS has been the issue.

Update rates are measured. LapTimer takes whatever it receives, it does not control the update rate. To get 4 or 5 Hz update rates from the XGPS, you need to update to the high update rate firmware available from Dual (please check the accessories area here in the forum).

On lateral acceleration on bikes: I worked on this today

- Harry

Harry wrote:Hi George,
On lateral acceleration on bikes: I worked on this today
- Harry

sounds great Harry - if you want a guinnea pig for beta testing, I can do it! We'll be racing this coming weekend and i plan to run the lap timer on my son's bike. i can send you the lap files afterwards if you'd like to review the measurements/calculations.

thanks

(my son, 16, on a kaw 250 at mid-ohio last year)

Coming weekend is far to early to test this feature , it will be part of v18. Till then, I'd suggest to use LapTimer's recalculation of acceleration values - that is not as precise as the measured values, but give you some rough values for motorbikes lateral acceleration.

- Harry