ArcGIS Mobile and Qualcomm GPS chips

Question

Has anyone had success running ArcGIS Mobile on a device with an integrated Qualcomm GPS chipset? I've tried to run the latest build (2525) on a Motorola MC65 with integrated Qualcomm GPS. The map works fine, and collecting line and polygon features works fine. However, I have great difficulty collecting point features. According to a Motorola engineer, the Qualcomm GPS has a "position lock" feature which prevents the GPS location from wandering when the user is stationary. Consequently, you don't see the normal wander of the GPS location as the position is updated by the GPS when the user is stationary. ArcGIS Mobile seems to have difficulty averaging positions (even if I set the averaging to just one position) to create a point feature due to this "position lock." Also, according to the Motorola engineer, this "position lock" feature cannot be turned off. Thanks!

DouglasBraeckel · Answer

Build 2550 did not solve this problem.

Is there a way the dialog can be captured and handled via code so it isn't even presented to the end user?

DouglasBraeckel · Answer

Jay,

We're seeing this problem with 2525 on any laptop running any gps.  I have tried using a Garmin 18x USB puck and an US GlobalSat BU-353 USB puck as well as the GOBI 2000 and GOBI 3000.  At some point, all devices will cause a disconnected error dialog.  This dialog will come up even if we are moving or stationary and usually when we have a good PDOP and at least a half dozen satellites.  I have covered the GPS up so number of satellites goes to 0 and that does not cause an error.  It appears to be totally random.

I am now downloading and installing Build 2550 and will report back if that does in deed solve our GPS problems.

Thanks,

Doug

JayChen · Answer

Mobile 10.0 Update 4 includes a bug fix for panasonic touchbook GPS averaging that's pretty similar to what you have seen. The bug was caused by the mobile application listening to GPSChanged event while at the same time, if user is stationary, GPS unit on some devices doesn't spill out any NMEA sentence as it assume user doesn't move. We changed the underlying logic in vertex averaging in these cases to let the mobile app go ahead with averaging if it already has a good fix. Mobile update 4 should be made available to customers recently.
Hi Erik,

Thanks for the reply. Sounds like the Qualcomm-based Gobi units work with averaging points and show GPS deviations. The Motorola MC65 is using the Qualcomm MSM7627 chipset, which looks to be different from the one used in the Gobi, so maybe this is something specific to that particular chipset. Interesting....

I've also had the same error message you have, but only upon resuming the MC65 after it has been suspended with ArcMobile and the GPS running. Other units using different GPS chipsets don't cause ArcMobile to throw the error message after resuming; they simply reconnect and display the location after a valid fix has been obtained. Maybe there are some compatibility issues between the Qualcomm chips and ArcMobile.

Build 2525 is the latest build of ArcGIS Mobile 10.

Thanks.