Dual XGPS160

[Harry]

Do you have a XGPS150 or a XGPS160? For the 150, 5 Hz is fine, the 160 should show 10 Hz.
Both the automatic and the manual recording should generate GPS recordings. In case you changed the system between steps #3 and #5, please check if you still had a GPS update rate of 5 Hz... You may have been affected by the iOS7.1 bug posted here: viewtopic.php?f=2&t=2214

- Harry

[GlnkNL]

Just did another test and made short acceleration video:

[youtube]http://www.youtube.com/watch?v=AY0KA0WFgTY[/youtube]

I synced it in Final Cut Pro by the first movement of the car to the first registration of increased GPS speed. The accelerometer is ahead of the GPS.

[Harry]

Play a bit with the Overlay Synchronization Video Delay in LapTimer -> Settings -> Expert Settings.
From what I see is the Video behind acceleration - which in turn means you should increase the value by 0.5 or 1.0 seconds.
Overlay again afterwards to check the results.

- Harry

[GlnkNL]

Do you have a XGPS150 or a XGPS160? For the 150, 5 Hz is fine, the 160 should show 10 Hz.
Both the automatic and the manual recording should generate GPS recordings. In case you changed the system between steps #3 and #5, please check if you still had a GPS update rate of 5 Hz... You may have been affected by the iOS7.1 bug posted here: viewtopic.php?f=2&t=2214

- Harry

I have the XGPS160. It does show 10hz:



But what I meant was this setting (refresh rate):



Why use 5hz and not 10hz?

[Harry]

That's an Expert Setting, please don't change it as long as not advised... This is a display update rate (the display is refreshed 5 times a second at least). Not related at all to GPS update rates.

- Harry

[GlnkNL]

Play a bit with the Overlay Synchronization Video Delay in LapTimer -> Settings -> Expert Settings.
From what I see is the Video behind acceleration - which in turn means you should increase the value by 0.5 or 1.0 seconds.
Overlay again afterwards to check the results.

- Harry

But the accelerometer is showing 0.6G of longitudinal acceleration before the GPS starts to show any increased speed.

[Harry]

I wouldn't take this too serious as GPS speed is always late - even with a 10 Hz device. This is due to filtering and signal processing. You can start compensating this by adjusting sensor delays for GPS (increase to pull the display forward), but I do not recommend this except in case you are willing to spend a lot of effort and time in finding the correct values for your device combination. All delays except the video synchronization show an effect during the next recording, so the test loop is complicated in addition.

- Harry

[froggy47]

I have this one working with the Bluetooth GPS provider app for android.

Am I supposed to "turn on" the app every time I go to use the gps? Seems like it won't pair unless I go fiddle with the app.

I posted the question to the app author.

Thanks!

[Harry]

I have this one working with the Bluetooth GPS provider app for android.

Am I supposed to "turn on" the app every time I go to use the gps? Seems like it won't pair unless I go fiddle with the app.

I posted the question to the app author.

Thanks!

Not sure I understand. Helper apps are usually used to get NMEA data from a paired BT GPS and feed it back into Android's location service. This in turn allows arbitrary apps accessing the location service to benefit from an external GPS they otherwise would not know / see / use. As long as you do not add the Bluetooth GPS in LapTimer's Sensor List, LapTimer will "believe" it accesses the internal GPS but receives the location stream from the external BT. Although this is probably working, this scenario adds another tool into LapTimer's sensor chain which at best passes through the data unchanged. No value but addition fault potential... As it will not be possible for LapTimer to access the external BT while the helper app is running, the other scenario is disabling the helper app and adding the BT GPS to LapTimer's Sensor List. This will enable LapTimer to access the BT GPS directly and will usually deliver the best results. Not disabling the helper app will not work in this scenario (no connect or other conflicts).

- Harry

[froggy47]

"Bluetooth GPS provider by MOBILE-J.DE" is the app recommended by DUAL in the owner's manual to "help" the Dual xgps160 connect to the android phone. So far as I know that is all the app does.

I needed it on my android phone to get the BT connection. It worked.

I thought you might be familiar with the app.

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Moving on, should I add the Dual xgps160 to HLT sensor chain or not?