I was in the mountains last weekend over a frozen lake and encountered a magnetic perturbation error. Had flown several times prior in other locations with no issues. I recalibrated and the error went away although the anafi seemed a bit unstable so I shortened my flight. It was a windy day and I wondered if the instability was related, but upon closer examination at home I noticed small nicks in the tips of two propeller tips. I replaced all the propellers and went for a test flight. Everything was smooth and stable again. The anafi has very small and thin propellers so important to frequently inspect them with your eyes and your finger tips...
Parrot anafi magnetic perturbations / crash
- Thread starter Owners_
- Start date
where are you located?
is this a new drone and where did you purchase from
we are assuming that prop came lose while flying - may not have been the case
approximately how may hours of flight time were on the props
did you change them recently
any previous crashes
if it was me & not a fairly new Anafi, I would just replace all props with new OEM parrot replacements and see what happens
but that is just my opinion as dealing with parrot can be an endless loop of frustration depending where you are located
If it was new with few flight hours and no prop changes, I would be reaching out to reseller for exchange
btw. I did have an an anafi fall from about 20 feet onto concrete due to failed battery.
did not break any props but bent the screw brackets where a couple of the props threaded into
so after replacing screws they were at an angle and not vertical
that unit was sent back and replaced by Parrot
best of luck and let us know how you make out
First off; you are a true hero and excellent pilots, you really rode it down all the way, in a controller matter.
The right front propeller indeed DID break in flight, I can tell you are 100% correct because of the video you supplied:
also, I have the magnetic error as well nearly all the time now in most concrete or near metal take off locations.
I believe that is because they are more strict now with the sensors.
Gipsz Jakab
Well-known member
I think it is hopeless to complain to the Parrot about a propeller break because you can’t prove to them that the accident was not a collision with a bird or a large insect, and it’s not a warranty issue.
@IronSky1 Your idea of measuring the magnetic field strength or deviation with the compass level application is really interesting and I will try it and compare it with a handheld real compass for hiking (I didn’t know this app and used the sensor tests app that includes the magnetometer check on 3 axis).
The reasons of my doubts on relying on an app are the following :
- First, my phone has a protection that keeps it closed with a magnet embedded in the protection material. Those little magnets are also the root cause of the misleading information when you use the GPS app to guide you on a map, when you see your car moving in an awkward position (like a ‘crab’).
- Even when I remove this phone protection, I still have errors that may be induced by the magnetic fields emitted by the phone itself, the components, the battery...
- Applications do usually work not with only one sensor, but do combine many of them, such as the tilt sensors (gyros...) and accelerometer, along with the GPS to determine the direction of the magnetic field depending on where you are on earth.
In France for example, the magnetic field is not exactly normal to the surface of the ground, it plunges to the ground at approx 20°, as at the North Pole, the direction of the magnetic field is ... at 90° just below your feet.
The use of this combination of sensors and the attached algorithms are smart but difficult to evaluate, where the handheld compass only gives you the direction of the magnetic flow... whatever the situation.
I’ll try it !
@Test2000 ... I don’t know witch of the 2 propositions is the most accurate :
- the OP is a hero because he could land his drone in a controlled manner after the loss of a prop (congratulations for you to capture the image of the shadow of the Anafi with the missing prop !)
- The development team at Parrot that could produce an algorithm that lets the drone equilibrate dispite the loss of a prop and land without damage (in a snow-foam blanket)... is the real hero ;o)
All in all, they are still working on the magnetic perturbations algorithm as they mentioned in the dev forum... and it still needs fine tuning...
But it’s a tough subject (they expect to make it work indoors also and I’m very interested for inspection purposes, where I remarked the Anafi is superior to a Phntom 4 for example)
The reasons of my doubts on relying on an app are the following :
- First, my phone has a protection that keeps it closed with a magnet embedded in the protection material. Those little magnets are also the root cause of the misleading information when you use the GPS app to guide you on a map, when you see your car moving in an awkward position (like a ‘crab’).
- Even when I remove this phone protection, I still have errors that may be induced by the magnetic fields emitted by the phone itself, the components, the battery...
- Applications do usually work not with only one sensor, but do combine many of them, such as the tilt sensors (gyros...) and accelerometer, along with the GPS to determine the direction of the magnetic field depending on where you are on earth.
In France for example, the magnetic field is not exactly normal to the surface of the ground, it plunges to the ground at approx 20°, as at the North Pole, the direction of the magnetic field is ... at 90° just below your feet.
The use of this combination of sensors and the attached algorithms are smart but difficult to evaluate, where the handheld compass only gives you the direction of the magnetic flow... whatever the situation.
I’ll try it !
@Test2000 ... I don’t know witch of the 2 propositions is the most accurate :
- the OP is a hero because he could land his drone in a controlled manner after the loss of a prop (congratulations for you to capture the image of the shadow of the Anafi with the missing prop !)
- The development team at Parrot that could produce an algorithm that lets the drone equilibrate dispite the loss of a prop and land without damage (in a snow-foam blanket)... is the real hero ;o)
All in all, they are still working on the magnetic perturbations algorithm as they mentioned in the dev forum... and it still needs fine tuning...
But it’s a tough subject (they expect to make it work indoors also and I’m very interested for inspection purposes, where I remarked the Anafi is superior to a Phntom 4 for example)
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the iPhone compass is only accurate if you use GPS.
Also my iPhone 12 Pro has a strong ring of actual magnets on the back of the phone, but the compass works still, maybe it was calibrated in the factory or the sensor is far away
The calibration of the magnetometer a device surrounded by fixed perturbations is the ‘hard iron effect’ and is now well handled by developers... as long as to calibrate your phone magnetometer with the ‘figure 8 dance’ on your phone or the Anafi ‘calibration’.
The problem may come from other factors such as the ‘soft iron effect’ (metallic things or fields that were not present at the time of calibration, your battery level and if your phone uses lots of current at the time of analysis, screen light dimmed or not, you wear an Apple Watch that you did not have during calibration, your mother in law is far to close for confort...)
The problem may come from other factors such as the ‘soft iron effect’ (metallic things or fields that were not present at the time of calibration, your battery level and if your phone uses lots of current at the time of analysis, screen light dimmed or not, you wear an Apple Watch that you did not have during calibration, your mother in law is far to close for confort...)
IronSky1
Well-known member
The iron effect is correct. I normally use a Samsung Tab S7 Tablet or a Note 10. None of my devices have simm card they are all off network. If I cannot get repeatability i donot fly using GPS. North should always be North. Good idea to
use a manual compass also it should validate the app / device signals
use a manual compass also it should validate the app / device signals
It is simple basically; you have 4 motors and 1 has only 50% of the props meaning lift cut in half at least for that one. If the other 3 lower their speed then it should be able to hover at least. But I don't know if the software could detect that?
In theory: if you initiate a landing and fly diagonal in the direction opposite of the broken prop it should be flying relatively stable relative to the ground position, I thought that is what the pilot did; combined with gimbal down it indicated to me that he was relatively in control
Is anyone traveling far with their anafi. It could be something your car is passing on the way to the field that effects your anafi magnetically a great deal. Also many electric cars have electric big motors
(and large magnets) in them today. You also may pass under normal high voltage lines on the way. Once they have that much field hitting them is one calibration good enough to solve the issue? Are two or more calibrations better in this scenario? How many feet is too close to a powerline before you run into perturbation issues? A cell tower?
Does it still effect the anafi being off while traveling?
(and large magnets) in them today. You also may pass under normal high voltage lines on the way. Once they have that much field hitting them is one calibration good enough to solve the issue? Are two or more calibrations better in this scenario? How many feet is too close to a powerline before you run into perturbation issues? A cell tower?
Does it still effect the anafi being off while traveling?
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