Hy there. I was making a walk. After 200 meters a set a new the home point for the remote position and started thr RTH. What i saw was a spark passing by me at full speed... when setting the cordinates of the remote the apps get the position of the mobile phone or RC? I made a few tests after it and it updated my position so it could be week GPS of the mobile or RC.

The moment i set the homepoint to RC

The moment i started the RTH

The moment i cancelled the RTH...

Very interesting, and very testable.  More evidence is needed before any conclusions are drawn, but one possibility is that the aircraft was "only" aware of original home point.  It looks to me like it is trying to return to original home point.  This doesn't look like a mistaken gps in any of the components.

I'm wondering if there is some latency in transmitting the new home point to the craft.  Time permitting I'll try some tests myself (testing DJI goggles is taking up some time).

Checking the direction it was going directly to the first home point... i hope...if not we are having a big problem... i was testing it befor enter the boat... where the first home point is not the final home point. The blue dot have been updated so i dont understand why it did not came to me.  Does the blue point is the mobile phone location and RC has another gps? And the GPS info provided to aircraft is the RC?

The RC has no build in GPS.

So... i cant explain this spark  behaviour...

ZukySpark Posted at 2017-8-26 04:49
So... i cant explain this spark  behaviour...

"Home point recorded. Please check on the map"

;-)

Where is the Hp? Maybe you can show it on the map?

I tested RTH mode for this use case.  I launched, set home point, walked and flew to a far location, and set home point to RC location.  I instructed the craft to RTH, and it behaved as though it was within close proximity of home point (which was the RC, and it was close).  I then performed another test.  I set home point to craft location, I then walked to a far different location, and set home point to RC location, then flew and walked to a completely separate location.  Original home point, RC home point, craft and myself were at all different locations.  I then instructed craft to RTH, and it ascended and flew to the RC homepoint location I had set.

This all is the exact behavior I would expect.  I have a theory about the author's situation.  Since the RC doesn't have GPS, it's using the phone GPS location.  What if the phone is not set up appropriately for pin-point GPS locations?  There's a lot of different settings for a phone's GPS.  If the phone was in a state where it could not identify it's GPS location, maybe the app doesn't know, and maybe the craft returns to original homepoint location.

This is another scenario that will be easy to test.  The tester can turn off location settings of phone and then try the same tests.

I am going to test it tomorrow again

ZukySpark Posted at 2017-8-26 10:17
I am going to test it tomorrow again

I had another theory as well...  there are gps modes of the phone where it can't/won't pinpoint your precise location, but it will use local towers and hotspots to identify your location.  In such cases, the phone reports your position as the location of the hotspot or tower.  That's the old way of doing things, and newer phones may not work that way anymore.  I may try to force it though and see how this impacts the behavior.

Another test:  This time I turned off location services of my phone to see how the spark and app would behave.  When I attempted to set home point to rc location, I received an error indicating that my gps signal was weak.  After I turned location back on, I was able to set home point.

I was unable to simulate my phone selecting a home point of a tower or hotspot (a location near me but not my precise location).  Phones may not do that anymore.

Looks like expected behaviour to me. No Gps on phone is detected

Charles Adams Posted at 2017-8-26 10:24
I had another theory as well...  there are gps modes of the phone where it can't/won't pinpoint your precise location, but it will use local towers and hotspots to identify your location.  In such cases, the phone reports your position as the location of the hotspot or tower.  That's the old way of doing things, and newer phones may not work that way anymore.  I may try to force it though and see how this impacts the behavior.

Exactly... Phones use a combination of GPS, tower triangulation and I suspect Wifi mapping to determine location.   I used to use my phone with a Bluetooth GPS to map my bike rides.. With the bluetooth GPS they were spot on.. but if I let the phones location services map my bike rides the tracks were all over the place, sometimes a block off.   It has been a few years, so maybe they phones are better now.. but I also suspect that "home point has been updated, check it on the map" is meant for this exact scenario :-)

The mobile i was using was the iphone 6. The blue dot ( my position checking on the map is correct and updated). By a reason i dont know at app it said it updated the home point but it did not...

When you update the home point. The distance showed in the app update should be updated to the new distance between you and spark right? It did not

Hi all

Pls watch my vid



And take note of the 1min 02 sec portion.

The map MUST rotate and orientate as you the the Remote Controller or your Smart Phone. if the Map does not Rotate, exit the app and go back in again.

If the map DOES NOT rotate, home point to Controller WILL NOT be marked or updated correctly  correctly.

This is a bug evident in Iphone and Ipad- may not for users of android phone.

I have reported this issue again and again but no one seems to take notice.

Could you refer the tutorial video and export all the data for analysis?

Hi, I have noticed that in some spark videos on youtube, there is a small red triangle and a "here" sticker with red color beside of it on the map. Is this a more accurate gps version?

"Here" symbole is present in this picture