Starling 2 Max no GPS data

Alex Kushleyev

@ROBERT-JUDD , the behavior of the RC receiver on the drone as is as follows:

when the Transmitter (Commando 8 ) is off, the receiver does not send (broadcast) anything
when the Transmitter is on, the receiver sends back telemetry packets (even if there are no telemetry updates from the PX4 side).

However, the GPS signal degradation seems to be related with proximity of the RC TX when the TX is on. The RC RX antenna is already located at the bottom of the drone and it should be OK, but there could also be some sort of interference, so possibly moving the RC RX antenna to the landing gear could resolve that (if it's an issue, TBD).

I don't personally have a spektrum analyzer for EMI scanning, but our team does and this work is also happening in parallel.

Will keep you posted!

Alex

ROBERT JUDD

@Alex-Kushleyev Did you have a test flight yet? How did the GPS perform while flying?

Thanks

Alex Kushleyev

Hello @ROBERT-JUDD ,

Apologies for the delay. I have been out of office and did not quite perform the testing I wanted last week. I am returning to testing this on Monday, will provide an update then.

Alex

Alex Kushleyev

Hello @ROBERT-JUDD ,

I was finally able to do basic flight testing with the GPS mast. I was able to observe 23-26 satellites reported by PX4. In my initial test I was not logging the SNRs in px4 directly, but i will repeat the test again (with SNRs logged) and double check that SNRs were high throughout the flight. I did not see number of satellites drop between non-flying and flying modes.

I will continue testing more actively in the next few days. Meanwhile, If you want to get your Starling Max flying with better GPS, I would recommend that you try to replicate my results using the mods from images i posted above. The only changes i made from those images was just orient the slot in the FR4 board towards the front of the vehicle so that i could align the GPS module in the same orientation as the original one.

Please note that when you move the GPS unit (which also has the magnetometer), the mag needs to be re-calibrated. Additionally EKF2 GPS POS px4 param should be updated if the location of GPS module changes. It looks like these offsets are just defaults (0) on the Starling 2 Max, which may be OK, considering the offset is pretty small.

Please let me know if you need any additional details to help you get started with the mods.

Alex

ROBERT JUDD

@Alex-Kushleyev Thanks for the update. I had to pivot away from this project and plan to revisit it when ModalAI has a long term fix. Have your colleagues made any progress identifying the source of the EMI?

Thanks again for your help.

ROBERT JUDD

@Alex-Kushleyev Circling back on this problem now, has your team identified the source of the EMI? Can I expect a long term fix that will allow me to fly my Starling 2 Max?

Thanks

CJoseph

Hey @Alex-Kushleyev,

I'm attempting this short term fix for a project I'm working on and I'd like to keep in line with recommended practices.

Can you kindly provide the .stl file used for the 3DP mount and also inform me of the material you used to 3DP?

Thanks in advance!
Christopher Joseph.

ROBERT JUDD

@CJoseph said in Starling 2 Max no GPS data:

Hey @Alex-Kushleyev,

I'm attempting this short term fix for a project I'm working on and I'd like to keep in line with recommended practices.

Can you kindly provide the .stl file used for the 3DP mount and also inform me of the material you used to 3DP?

Thanks in advance!
Christopher Joseph.

@Alex-Kushleyev: I'm also planning to repeat your modification, and the .stl file would be very helpful to me as well. I tried a different modification yesterday but it didn't work, so copying yours is my next step.

Thanks for your help.
Bob Judd