HLT doesn't record acceleration data when using external GPS

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ereynold60
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Re: HLT doesn't record acceleration data when using external GPS

Post by ereynold60 »

I'm using a Dual SkyPro XGPS160... I don't think there is an option to lower its update rate from 10Hz...??
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Harry
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Re: HLT doesn't record acceleration data when using external GPS

Post by Harry »

LapTimer / Administration / Sensor List / Dual XGPS GNSS has an option. Not sure to which update rate it switches (need to check the code), please try the option.

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No_Skillz
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Re: HLT doesn't record acceleration data when using external GPS

Post by No_Skillz »

I have the same issue but it looks like there is acceleration recorded, just very erratic. Harry, I did your instructions to recalculate and I see the following - see attached.

Prior to doing the recalculation there is maybe 3-5 recordings only.
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Harry
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Re: HLT doesn't record acceleration data when using external GPS

Post by Harry »

You need to smooth the data. Currently, noise of positions is the dominant source of acceleration. Shift the slider to the right. Light means no smoothing.

- Harry
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Re: HLT doesn't record acceleration data when using external GPS

Post by No_Skillz »

Only applying "strong" smoothing eliminates the spikes. However I think something is wrong because it is showing no more than 0.75g on any corner. I am fairly experienced driver on R-compound tires that can hit 1.5g pretty consistently in other times.
godnamnit
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Re: HLT doesn't record acceleration data when using external GPS

Post by godnamnit »

I have the same issue! Been really frustrated since I have a track day tomorrow. I am pretty sure it's a bug introduced after the latest update. On the video preview screen while recording, the accleration values are displayed correctly. But they are not saved if an external GPS (dual skypro) is used. Only if I disable the external GPS and use internal (1hz) one, the values are saved.

In case I am posting two duplicated replies. Please delete my earlier one.
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Harry
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Re: HLT doesn't record acceleration data when using external GPS

Post by Harry »

godnamnit wrote:I have the same issue! Been really frustrated since I have a track day tomorrow. I am pretty sure it's a bug introduced after the latest update. On the video preview screen while recording, the accleration values are displayed correctly. But they are not saved if an external GPS (dual skypro) is used. Only if I disable the external GPS and use internal (1hz) one, the values are saved.

In case I am posting two duplicated replies. Please delete my earlier one.
Please make sure you see a GPS update rate of 10 Hz while driving. In case you see 10 Hz and do not get acceleration, it is a problem with app/adapter etc. In case you do not get 10 Hz, it is a problem with the GPS connection.

- Harry
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godnamnit
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Re: HLT doesn't record acceleration data when using external GPS

Post by godnamnit »

Harry wrote: Please make sure you see a GPS update rate of 10 Hz while driving. In case you see 10 Hz and do not get acceleration, it is a problem with app/adapter etc. In case you do not get 10 Hz, it is a problem with the GPS connection.

- Harry
While driving, I see both the 10hz GPS update rate (skypro) and my phone's (30hz) internal acceleration sensor working. The acceleration data is just not stored in log.
ereynold60
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Re: HLT doesn't record acceleration data when using external GPS

Post by ereynold60 »

godnamnit wrote:
Harry wrote: Please make sure you see a GPS update rate of 10 Hz while driving. In case you see 10 Hz and do not get acceleration, it is a problem with app/adapter etc. In case you do not get 10 Hz, it is a problem with the GPS connection.

- Harry
While driving, I see both the 10hz GPS update rate (skypro) and my phone's (30hz) internal acceleration sensor working. The acceleration data is just not stored in log.
Same here. I had a track weekend 2 weeks ago, and no acceleration data is stored, except at S/F and split points. I have Dual SkyPro at 10hz.

Strong smoothing only seems to apply to lateral acceleration, as I still see very spiky behavior in the longitudinal axis.
ereynold60
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Re: HLT doesn't record acceleration data when using external GPS

Post by ereynold60 »

ereynold60 wrote:
Same here. I had a track weekend 2 weeks ago, and no acceleration data is stored, except at S/F and split points. I have Dual SkyPro at 10hz.
Now here is something interesting / confusing. I exported my data to VBO and when viewed in CircuitTools, the acceleration data IS there... no smoothing or re-computation performed. So it must be in LapTimer's DB somewhere and just no showing in LapTimer screens or in Overlays ???
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