Flytrex or Solar storm? (Sensitivity of the Naza GPS)

[coreyperez]

I've logged 11 flights with my 550 and never had a single GPS issue until I installed the Flytrex "core". GPS issues nearly every flight now. Plus, the Core isn't recording any flight data.

The lovers of the flytrex unit are pointing out I'm the only guy having an issue, but to eliminate that, I'm curious how sensitive is the Naza-M V2 GPS with Solar Storms? (One going on right now with a "Class M Flare" (whatever that means).

Its dark out now, but I'm going to try and pull apart the 550 and junk the Flytrex. I want to see if that is my issue.

Anybody else having GPS issues? Is the DJI THAT sensitive? My car never gets me lost...

Hmmmmm

Corey

 

[coreyperez]

http://youtu.be/Z8SkrsIrwxY - All red flashes (Flytrex installed) - "holding", but GPS could fail at any point = undependable / unsafe for a "Fail safe" (RTH) consideration.

http://youtu.be/wqpGIaLaIG8 - GPS Locked (Flytrex removed), RTH not tested due to it being my 2nd night flight, I'm right near a airfield traffic pattern and I was not sure I could regain control IF something went wrong.

I know these videos are not right after one another, but I did fly the 550 with the flytrex and had GPS issues, walked in to my room, pulled it out, put in a fresh battery and 100% SOLID GPS lock 15min later... All while the same solar storm was going on.

As I've stated before, I do not believe a DJI Equipped craft can be considered "safe" if you depend on or require GPS/Failsafe while using the Flytrex. Mine may be defective, but the point has been proven.

I'd also like to point out I'm happy it is the flytrex and not a issue with DJI not being able to withstand Solar activity!

Corey

 

[Benjamin Kenobi]

I noticed the solar storm and decided not to fly yesterday. I honestly think we're being over cautious though. The only actual research papers I could see from a quick glance on the web all seemed to suggest GPS receivers worked better when the Kp was high. Go figure?

Anyone find any research on GPS and solar stuff?

Maybe I'm thinking about it wrong. Maybe it's the electrical disturbances in circuits that's a problem. That is well documented where solar storms cause surges and blackouts.

Hmmm, food for thought.

 

[Marcus]

Solar Storms will not affect our GPS units - period.

25 yrs in the Satellte industry talking now

 

[Benjamin Kenobi]

Excellent! That's what I have come to believe.

Can they affect any aspect of our UAVs to your knowledge?

 

[Marcus]

Excellent! That's what I have come to believe.

Can they affect any aspect of our UAVs to your knowledge?

GPS Satellites are less prone to interference from Solar Storms as they orbit at a relatively low altitude. Geostationary satellites are much more at risk as they fly so high, they build up static charge as the solar disturbance (which takes the practical form of an actual wind) blows past the craft. In addition this solar wind causes satellite attitude disturbances as it buffets the large solar panels powering the craft.
GPS Satellites are actually very well insulated from radiation as their operating altitude is close to the Van Allen belt, so they have to be.
GPS Satellites have been affected by Solar storms but it is extremely rare. Last time there was a service or accuracy interruption was like 2005 or so.

 

[Benjamin Kenobi]

Great reply. I think we've established that GPS is not affected. But what about other components? It has been documented about electrical surges linked to high solar activity. Not in UAVS or aircraft though, just ground based systems like the power grid.

 

[Marcus]

Great reply. I think we've established that GPS is not affected. But what about other components? It has been documented about electrical surges linked to high solar activity. Not in UAVS or aircraft though, just ground based systems like the power grid.

Well what people call magnetic storms or disturbances are caused more by single coronal ejections which essentially send a higher power “pulse” of particles which can upset the Earths magnetosphere which in turn can create a kind of magnetic storm. This doesn’t really have much of an effect on most things but high power lines can act as a huge receptor, a kind of antenna if you like, and the magnetic field, as it ‘storms’, can induce power spikes on the lines tripping out power sub stations and stations.

 

[coreyperez]

I know for myside (Military Aviation) we do take solar activity (storms, etc) into planning consideration because of the havoc they play with our radios, UHF, VHF and our FM's suck regardless. While we have work-around for most of these issues, we have to keep them in consideration due to how we make our movements and develop our plans. I suppose while the Solar storms may not mess with the GPS, I wonder how the interference plays out with our ability to control our multi-rotors. (Applying the bands we use for voice communication). I've seen instances in higher storm ratings (ratings we as Military Aviators) destroy como capabilities (un-aided/modified) to the point of not being able to talk from our normal reporting point to controlling agencies, where as any other time it is 5x5 on como.

I don't plan to do any FPV stuff in the near future, but something else to review I suppose!

Corey

 

[Marcus]

I know for myside (Military Aviation) we do take solar activity (storms, etc) into planning consideration because of the havoc they play with our radios, UHF, VHF and our FM's suck regardless. While we have work-around for most of these issues, we have to keep them in consideration due to how we make our movements and develop our plans. I suppose while the Solar storms may not mess with the GPS, I wonder how the interference plays out with our ability to control our multi-rotors. (Applying the bands we use for voice communication). I've seen instances in higher storm ratings (ratings we as Military Aviators) destroy como capabilities (un-aided/modified) to the point of not being able to talk from our normal reporting point to controlling agencies, where as any other time it is 5x5 on como.

I don't plan to do any FPV stuff in the near future, but something else to review I suppose!

Corey

Low frequency bands up to 18-20Mhz can exhibit some performance issues due to the ionosphere becoming charged more than normal in high activity storms, but above that nothing really.. FPV Freqencies, even the lower long range freqs, are unaffected. Additionally their usage does not even require reflection by the Ionosphere.

Truth is, Solar activity has been used as a scape-goat for many years by various service advisors... Mud sticks

UAV's have never been affected (so far) by any Solar activity.

 

[coreyperez]

Alright, alright...

It was my fault! Below is my final email (regarding my Core problem). Its corrected, recording and I'm happy! (Unless I missed it, they need to update the information about required file system)

Corey

Amit,

It’s been some work, (nearly 20 unsuccessful flights) but I’ve finally solved the mystery on my end. There were numerous problems, most of which I’m sure were my improper cable configuration.

The final solution:
This has to be plugged into the GPS, not PMU that the GPS is plugged into (I accidently used the wrong cable).
My Naza would typically get GPS lock, but sometimes wouldn’t, the Core never recorded flights. I never was aware until removing the Core that there was a LED indicator (nowhere mentions what the light is signaling). I’m not sure if there was any light indications when it was mounted inside the frame of the F550. Upon changing configuration (cable) I noticed two flashes, pause, two flashes…

The Core requires a file system (on the SD Card) of “FAT”, not NTFS (which I typically use).
I had tried FAT, FAT32, ExFat and NTFS previously with no luck, in hindsight the issue was the cable wasn’t connected properly.

After numerous different SD Cards (different classes, different manufactures, different formats) I’m successfully using a (Either Class 4 or 6) Sandisk 1GB MicroSD with a file system of FAT.

The only issue I still have is the NAZA GPS cable is unable to be properly secured in the Core. My current solution is using some tape to secure it to the core with a constant check before pre-flight (why it is currently mounted on top right next to the GPS). When it was in the frame, it was very hard to visually check that the cable was properly secured, and the main reason I used the wrong cable initially.

Thanks for your assistance, I’ll continue to keep an eye on the plug as I’ve tried numerous different methods to remove tension, and the current solution (while appearing to pull the cable out) actually is binding it, thus providing tension.

One last question. I showed a friend of mine (Currently in Korea as well) how fancy this device is now that I’ve got it working. My question is, what is your timetable for producing this device for different flight controllers? What information does this actually need from the Naza system? Could the end user just plug in a Naza GPS (with power) while it is attached to a different flight controller? It is my impression that the Core is figuring all the information out on its own, only using the Naza GPS for signal. I’ve currently got another multirotor (Quad with KK2.1) and looking to get a TBS Discovery with XAircraft SuperX and would love to have this on those aircraft as well. Could I possibly just branch power and GPS signal to the Core for GPS tracking?

Thanks,

Corey

 

[PeteDee]

Flying yesterday with Flytrex installed and had 8-9 sats each flight, no problems getting fast home lock too.

Pete

 

[coreyperez]

Pete,

Does it state somewhere how many Sat lock it has?

One other quick question. I was on the fence about getting a Discovery Pro and was curious about your opinion of it vs the non-gimbal Disco. I understand, it fully depends on what I plan to do with it, I was curious if the pro was worth swapping my hero 3 back and forth on. Lastly, are you using the bullet proof motors/esc? Thoughts?

Corey

 

[PeteDee]

Hi Corey,

I use Mini OSD so have the info on my screen.

I have several GoPro's, makes life easier.

I have original TBS ESC's and TBS 900kV motors on my Disco and Afro 30A ESC's and Birddog 900kv motors on my Pro, performance is pretty much the same on both.

The video from the Pro is brilliant, you can get better from a bigger setup I am sure but they are a ***** to transport, the Pro is just so easy.

Pete

 

[coreyperez]

I guess now that I think aobut it, I thought the Pro had a built in OSD.

The other info is what I was looking for. My Hex has become a beast now that the gimbal and landing gear is mounted.

I'm looking or something that is portable with a gimbal. I figured the Disco Pro would be a great place to work from.

Corey

 

[PeteDee]

It has Core OSD, the Core only has basic info, the Mini OSD runs over the top and add more info, height, distance, speed, rise/fall indicator, artificial horizon, direction to home.

The portability of the Pro is excellent and makes it easily worth the money.

Pete

 

[coreyperez]

Is the "Mini OSD" the one from HK?

http://www.hobbyking.com/hobbyking/store/__29798__mini_osd_system_w_gps_module.html

I've been having a hard time deciding which one to get. Plus, Ebay has x4 ebay bucks tomorrow! WHOOHOO! On purchases over $150. I found a set of bulletproof motors/esc. But I'm not quite read to pull the trigger on those quite yet.

This is the OSD I was initially considering:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=310897638970

I just got my ground station monitor and I'd have to say I'm pretty impressed with the quality for a cheap 7" ebay monitor!

Thanks for the info!

Corey

 

[PeteDee]

DJI Mini OSD, plugs into the V2 Naza.

http://www.dji.com/product/iosd-mini

 

[coreyperez]

Thanks again Pete, I ordered the Mini last week.

Corey