Thanks for The Help

HI, Can't help but keep those procedures in mind now... Thank you...

sSunsets Posted at 2018-5-11 16:20
HI, Can't help but keep those procedures in mind now... Thank you...

Good hope it helps.

Martinaharg Posted at 2018-5-11 12:21
Thanks for The Help

Your welcome....

i did everything by the book and still i had had compass error and after that i had gps lost. FLY AWAY birdie. I can not find it anymore.. my spark is lost. Any tips how get some compensation for this malfunction?

eelco Posted at 2018-6-26 02:00
i did everything by the book and still i had had compass error and after that i had gps lost. FLY AWAY birdie. I can not find it anymore.. my spark is lost. Any tips how get some compensation for this malfunction?

Only tip I can give you is send drone in for analysis.

eelco Posted at 2018-6-26 02:00
i did everything by the book and still i had had compass error and after that i had gps lost. FLY AWAY birdie. I can not find it anymore.. my spark is lost. Any tips how get some compensation for this malfunction?

You can try pleading with DJI, sending in any FlightLog data from GO-4 app.  
However, based on lost drone stories posted here, without drone to send in, you are probably out of luck.

Maybe Netherlands has consumer law that would help?
Or possibly your own insurance would cover part of cost of replacing drone?

Awesome tips! Thanks for posting bro!

Aaron Avila Posted at 2018-7-22 17:04
Awesome tips! Thanks for posting bro!

Your welcome.

Hi.

Excellent and usefull info.

I took the liberty of translating the text into Portuguese to facilitate reading by those who do not speak the English language (and converted the distances from feet to meters):


DICAS PARA AJUDAR A EVITAR INTERFERÊNCIAS E BLOQUEIOS DA BÚSSOLA

1.        Nunca calibre a Bússola a menos que seja solicitado.
2.        Iniciar o AC até receber sinal de GPS suficiente.
3.        Se você receber informação de interferência da bússola, desligue o AC e vá para outro local, sem interferência.
4.        No canto inferior esquerdo do seu mapa você verá um triângulo vermelho pequeno, verifique se este triângulo está a apontar na mesma direção do seu AC, isso mostrará uma boa bússola no chão.
5.        Execute o seguinte procedimento:
•        Levante AC para a altura de 2,5m
•        Ponha o AC a pairar por 20 segundos
•        Voe 1 m para frente
•        Voe 1 m para trás
•        Voe 1 m à esquerda
•        Voe 1 m à direita
•        Voe 1 m para cima
•        Voe 1 m para baixo
•        Guine para a esquerda
•        Guine para a direita

Se você tem uma boa horizontal de cada vez, então você saberá que tem um bom estado do GPS, do IMU da bússola, e o seu AC está pronto para voar.

Este exercício leva menos de 2 minutos e vale a pena fazer antes de cada voo!

PedroHugo Posted at 2018-7-23 03:32
Hi.

Excellent and usefull info.

Hey good job, thanks for that, very helpful.

Thanks! I’ve been doing this since I first read it a couple of months ago and I feel much more confident when I take off after I’ve done this simple procedure.  

thank you for that tip!!!!!

This is very good practice, however this takes 2 precious minutes out of ONLY 10 to 12 min. of real flight time!

ssylca44 Posted at 2018-7-29 07:02
This is very good practice, however this takes 2 precious minutes out of ONLY 10 to 12 min. of real flight time!

While I say 2 minutes, it probably takes less than 1 minutes, once you become accustomed to doing it.
Good luck.

1/ Never calibrate Compass unless prompted to.

Is this valid for Mavic Pro as well? On the NEW manual for Mavic Pro DJI changed what they recomend about this. The old manual was recomending the same approach as you for Spark.

alexmbraMav Posted at 2018-7-31 20:49
1/ Never calibrate Compass unless prompted to.

Is this valid for Mavic Pro as well? On the NEW manual for Mavic Pro DJI changed what they recomend about this. The old manual was recomending the same approach as you for Spark.

Calibration of compass while not difficult, is entirely up to the user, while advice given here was for Spark , I would offer exactly the same for Mavic Pro, I’m not sure why new recommendations came for Mavic Pro , I’ve had mine for almost two years, I’ve calibrated once, I’ve travelled to many different locations covering large distances and have not needed to calibrate either spark, Mavic, or P4Pro, I will always check compass values in my craft before launching as well as checking compass arrow to make sure correct heading of aircraft.
Calibrating a perfectly normal working compass will not have the effect of making it any better, but there is a risk of making it worse

Calibration gives the compass the information it needs to determine which magnetic influences are part of the Mavic and what is the earth's normal magnetic field.
The compass doesn't lose calibration and doesn't ever need re-calibration unless you add or remove equipment to/from the Mavic.

I’m not sure why new recommendations came for Mavic Pro

It would be nice if someone from DJI explain the reason for this change for us. ;)

alexmbraMav Posted at 2018-8-1 03:13
I’m not sure why new recommendations came for Mavic Pro

It would be nice if someone from DJI explain the reason for this change for us. ;)

Well as usual nobody seems to know why, but I think that most users will use common sense, I use basically what works for me and so far I’ve had no problems.

Good to know - thanks.

Warriewoodlad Posted at 2018-8-2 23:12
Good to know - thanks.

Your welcome. Hope it helps..

Thanks for the informative

Thanks for the informative

hallmark007 Posted at 2018-8-1 02:47
Calibration of compass while not difficult, is entirely up to the user, while advice given here was for Spark , I would offer exactly the same for Mavic Pro, I’m not sure why new recommendations came for Mavic Pro , I’ve had mine for almost two years, I’ve calibrated once, I’ve travelled to many different locations covering large distances and have not needed to calibrate either spark, Mavic, or P4Pro, I will always check compass values in my craft before launching as well as checking compass arrow to make sure correct heading of aircraft.
Calibrating a perfectly normal working compass will not have the effect of making it any better, but there is a risk of making it worse

Hallmark.

You say: "The compass doesn't lose calibration and doesn't ever need re-calibration unless you add or remove equipment to/from the Mavic."

According to DJI, compass may slowly lose calibration with time. DJI does recommend to re-calibrate it from time to time even if drone is not used (see Mavic Air manual).

Also, compass may lose calibration if you store Spark close to strong magnetic fields. While I have not experienced it myself, I did read some accounts proving that, For example a person put Spark close to his car subwoofer while driving and it caused severe mis-calibration (parts of  Spark got magnetized?).

In addition JJB did some experiments when DJI GO showed normal compass yet he was experiencing sporadic compass errors. After very slow and very careful re-calibration, his compass issues disappeared while DJI GO measurements did not change.

The above examples just show that we should be vigilant. Absence of errors does not prove that all is OK. For myself I do re-calibrate my compass when travelling long distances (although, admittedly, I forgot to do it on my last trip and all was fine), and I sporadically check my flight logs for any abnormalities in addition to checking compass and IMU status in DJI GO.

Mirek

Mirek6 Posted at 2018-8-23 10:51
Hallmark.

You say: "The compass doesn't lose calibration and doesn't ever need re-calibration unless you add or remove equipment to/from the Mavic."

I always check both compass and IMU preflight and recommend all do the same , I also check compass heading with aircraft heading, I also recommend calibration if app requests, which should happen if there is a problem with compass, and this is also recommendation of your spark manual.

Regarding compass loosing , I have been flying for a number of years and have never known or seen compass loosing calibration, without some interference, these are digital compass so should never lose calibration unless outside interference. If you choose to calibrate your compass then I don’t see anything wrong in that, it’s your Aircraft .
As a commercial operator and also known many other operators, they use the same principle as I do. I’m not sure why you mention Mavic Air without also mentioning other dji aircraft, for instance P4Pro manual recommends only calibration when apps warns you, just like the spark.
I’m not interested in giving out wrong or bad information, but trying to help others where I can, I see many using above preflight practices and flying quite happy and safe.

hallmark007 Posted at 2018-8-23 11:32
I always check both compass and IMU preflight and recommend all do the same , I also check compass heading with aircraft heading, I also recommend calibration if app requests, which should happen if there is a problem with compass, and this is also recommendation of your spark manual.

Regarding compass loosing , I have been flying for a number of years and have never known or seen compass loosing calibration, without some interference, these are digital compass so should never lose calibration unless outside interference. If you choose to calibrate your compass then I don’t see anything wrong in that, it’s your Aircraft .

Yes - all is appreciated and your advice is sound.

I am just saying that being vigilant may help.

I gave you JJB example which I did witness. DJI Go showed all fine (compass normal) yet JJB was experiencing compass and yaw errors during flight. After careful compass calibration the compass and yaw errors went away.

This did prove to me that you may need to re-calibrate compass even though DJI Go says all is OK. DJI Go is not known to be a particularly stable app :-).

In summary - yes - in large majority of cases what you say will work flawlessly. However, there may be some cases, which you did not experience (I didn't either), which are different.

I gave example of Mavic Air manual on purpose - DJI is not consistent with their message.
This, to me, means - be vigilant. Perhaps they are wrong in Mavic Air manual and right in Spark manual.
Or perhaps the opposite. I do not know.

Mirek

Mirek6 Posted at 2018-8-23 13:18
Yes - all is appreciated and your advice is sound.

I am just saying that being vigilant may help.

I fully understand where your coming from, and your attitude that you are the one responsible is the correct one to take and end of the day , we are all trying to help each other both learning and giving advice.
Good Luck.

hallmark007 Posted at 2017-7-19 08:51
Issues with bad compass will be compass heading will be off so when you push stick to go forward you Aircraft will want to go in the direction of compass, so conflict between controller compass and gps, these drones seem to be designed that if there is conflict between compass and gps, gps tends to give up and Atti takes over, but by this time usually AC is out of control.

A lot from what I see is compass problems with these drones can take place on the ground, taking off near metal objects, power lines, rebar concrete, this is why I recommend checking compass heading and also not just take off up to 50 feet where it's almost impossible to recover,

I have had 3 drones other than DJI and learned by necessity to fly them in Manual Mode. To me the main use of the gps is to RTH.

You seem to imply that, if the Sparks gps, imu and compass fail or disagree, all is lost.

Surely the Atti mode is similar to the Manual mode in less capable drones without gps. So if in VLOS, the pilot takes over and brings the drone home. If the drone is outside VLOS, well we have been advised not to go there.

Warriewoodlad Posted at 2018-8-23 14:45
I have had 3 drones other than DJI and learned by necessity to fly them in Manual Mode. To me the main use of the gps is to RTH.

You seem to imply that, if the Sparks gps, imu and compass fail or disagree, all is lost.

I have never said anything of the sort, and I’m not sure where you got this information , in fact I’m a big fan of flying in Atti mode, I had tofly in Atti mode to gain my SUA pilots license.

I'm sorry if I  interpreted this phrase incorrectly : "gps tends to give up and Atti takes over, but by this time usually AC is out of control".

Did you mean that the AC would no longer respond to RC commands when in Atti mode?  I would appreciate a clarification if wouldn't mind.

I'm not being critical, but trying to prepare for the possibility where my Spark might behave badly. I would like to believe that if the imu, compass and gps go off-line, there is a good possibility I could take effective control in the Atti mode.

Warriewoodlad Posted at 2018-8-23 18:57
I'm sorry if I  interpreted this phrase incorrectly : "gps tends to give up and Atti takes over, but by this time usually AC is out of control".

Did you mean that the AC would no longer respond to RC commands when in Atti mode?  I would appreciate a clarification if wouldn't mind.

The craft will fly fine in Atti mode, but in wind and if out of VLOS it can be very difficult to control, many try to get control but panic and give up, going into Atti mode should always warn you to first try to land your craft safely, landing is always the best and safest option.
So if it happens just think left stick down 100% and try to control orientation with right stick best you can.

Good advice.
Hopefully it is extremely rare to lose imi, compass and gps all at the same time, because I think that every Spark owner occasionally strays out of VLOS.

Hi folks,

Being a drone pilot for many many years, I'll happily share when I do a compass calibration:

i) Before performing a flight at a position more than ca. 100km away from the last flight position
ii) Every year before the first flight
iii) Changes on your drone (metallic labelling, new propellers etc.)
iv) After a crash
v) When the Go4 app instructs to do so

Why do I do so?
Well, the compass sensor relys on the Earth's magnetic field, which is /not/ static. It is changing, so from time to time a calibration is a good thing (google "toilet bowl effect").
Some may think, after a crash Sparky "loses" its calibration. That's IMHO nonsense. The impact may however have moved around the circuit boards a little bit (because the drone's hull is bent a bit or so) or impact changes the properties of the compass sensor. So a compass calibration is advised in that case. Of course followed by a through check if the compass is still functioning correctly before the next flight.

HTH,
Wolferl

Warriewoodlad Posted at 2018-8-24 03:01
Good advice.
Hopefully it is extremely rare to lose imi, compass and gps all at the same time, because I think that every Spark owner occasionally strays out of VLOS.

Warriewoodlad,

Unfortunately it takes only one of them to fail, for whatever reason, and Spark may go to ATTI :-(.
It is rare, but as you can see if you follow this forum, not that rare.

Even if AC is out of sight but you have WiFi range, you can still control it quite well by using your telemetry data, and compass map on your DJI GO,

With Spark's size, if you fly further than perhaps 200 metres, you are bound to lose its sight. It still may be in VLOS but will be too tiny too see. I fly Spark blind (just relying on DJI Go display) all the time. I try not to get any obstacles between me and Spark - so it is in VLOS (better WiFi reception) - but flying distances of up to 500 metres (legal limit in my country) I cannot see it.

Mirek  

Wolferl Posted at 2018-8-24 03:49
Hi folks,

Being a drone pilot for many many years, I'll happily share when I do a compass calibration:

Good list.

Add one more: If you start getting unexpected compass/speed/yaw errors which you cannot explain by flying in area with some interference. Re-calibrate compass and, possibly, IMU even if DJI GO shows that everything is normal. DJI GO is known to be wrong from time to time :-).

Mirek

today happened to me. I wonder, why does the drone go into atti mode when it loses its bussola? it is not able to hover when it is only with GPS?

Many Android phones do not even have a compass sensor, but they are able to inform the north / south / east / west orientation because it has only one GPS sensor.

I think the drone should be able to hover only with the GPS, besides that it should calibrate its bussola in flight - comparing the data with the one of the gps - when it gives some error in the bussula in flight.

uildes Posted at 2018-8-25 18:23
today happened to me. I wonder, why does the drone go into atti mode when it loses its bussola? it is not able to hover when it is only with GPS?

Many Android phones do not even have a compass sensor, but they are able to inform the north / south / east / west orientation because it has only one GPS sensor.

Hi uildes,

For Android, there are numerous apps like "GPS Status" which do show a compass needle. So there must be some kind of sensor for this to work.

GPS just gives you "geo coordinates". GPS does not know anything about "headings". If the compass fails, a drone can't correctly counteract a wind drift, because it doesn't know  where the aircrafts nose points to in relation to geo north. One needs to know that GPS isn't very precise, fixes wander around by a few metres. Because of that a drone can't reliably compute its relative heading as long as it is hovering.

Cheers,
Wolferl

uildes Posted at 2018-8-25 18:23
today happened to me. I wonder, why does the drone go into atti mode when it loses its bussola? it is not able to hover when it is only with GPS?

Many Android phones do not even have a compass sensor, but they are able to inform the north / south / east / west orientation because it has only one GPS sensor.

Magnetic interference is usually picked up on the ground, aircraft warning system does not always pick this up , I will try explain below what may occur when magnetic interference is picked up from ground or surrounding area.

The best way I can explain this is. If you put your Aircraft on the ground in normal circumstances, start it up, then lift it up and turn it 90 degrees to the right both your compass heading and IMU will both move together 90 degrees and no problems.
If you put your Aircraft on the ground and there is magnetic interference only the heading of your compass will change, your aircraft will still take off. But when it clears magnetic interference compass will then move to correct heading which you would think was great. But No, what happens is IMU is then conflicted and confused because of this sudden movement by compass, so you receive IMU exceptional heading warning, your aircraft cannot deal with data conflict so decides to switch to Atti mode dropping gps in favour of compass simply because aircraft can fly without gps but not compass.

While I can’t be certain you picked up interference from the ground or surrounding area it is the most common cause.
I have seen many cases where people start their aircraft in or on their car in their house and then bring it outside so damage is already done and we will see exact same warnings and and reaction from aircraft.

We all should check our compass when we start our aircraft and maybe more of this could be avoided, you can do this by checking the compass values in your app also check small red triangle in the lower left corner of your telemetry, it should be on the same heading as your aircraft.

One last thing I will say is we must always try to land aircraft immediately when this occurs.

Hi hallmark007, thank you very much for all the advice you provide us noobies!

Perhaps you could help me understand these points further:

1. "aircraft can fly without gps but not compass" - Why not? Why couldn't they follow forward/backward/right/left commands, without knowing where is North? Just like a car does...

2. "we must always try to land aircraft immediately when this occurs" - Please, see if I got it right. ATTI mode is like a more manual mode, it seems to be a feature of other models and people may wish to fly on that mode (not to forget that it's more dangerous and thus requires more expertise... and also that some regulations may actually require this skill...). However, in the case of Spark, going ATTI after a failure or conflict of subsystems (GPS, compass, IMU) makes the AC particularly hard to control, even to the average ATTI-savvy pilot? If I got it right and the answer is "yes", then why is that? That is, why should people feel relatively safe flying a Phantom in ATTI but not a Spark?

Sorry the bother, I just want to know.

Thanks!

CoopSTAY Posted at 2018-8-31 07:07
Hi hallmark007, thank you very much for all the advice you provide us noobies!

Perhaps you could help me understand these points further:

You will not be any safer flying a phantom than a spark/Mavic in Atti mode, yes because of the light weight of the smaller aircraft it may be taken further faster in the wind. But just like spark the system for going into Atti mode is the same on spark as phantom. If you are trying to get fancy and control your craft many things to think about, if you can just think one thing, left stick down land.

Why it needs compass and can’t fly without it, that’s another debate and I’ve been through that in the past, there are some who think there might be a better way and they could be right who knows, but for now dji and all other consumer drones operate the same way, so my comments are more to do with how these drones work, not so much with how they could work a different way.
It really is another debate and not as simple as some might think.
Thank you