Hello.

I have problem with "Ultrasonic sensors error" in my Mavic Pro Platinum.
In flight I get this message: Ultrasonic sensors error - land immediately
After message, drone are going up (run up) - when I try to pull him down - it don't want to go down - no reaction.
If I keep the stick down for few seconds - drone is landing
I get this message at different heights (near ground or at 75 meters) and at different times (there is no rule for this).
I did calibrate IMU and compas twice. No luck

I have latest software in drone and radio. Latest version of DJI GO 4 app.

I fly with leg extensions (PGYTECH) landing gear



When I remove them (landing gear) - there is no problem with ultrasonic sensors error - I can fly and drone is not running up.
I did investigation and problem is with rear legs (they are near ultrasonic sensors). I have check if they are properly attached to drone (to small legs) - they stick well (they do not move), they are correctly attached (they do not cover the sensors) . I remove the rear legs (front are still on drone) - there is no problem with flying.
I even try to grind little (rear legs) - so there is more space between legs and sensors - but no luck.
I guess the sensors catch rear extended legs.

But the best thing is that I've already used this landing gears earlier (the same model but different piece - Pgytech landing gear and mavic pro platinum).
I've lost previous legs, and have another mavic pro platinum (I crashed first one).

So, maybe I get a defective piece of Pgytech landing gears or my sensors in mavic pro are more sensitie than in my first mavic pro. Maybe DJI increased their sensitivity in new version of software ?

I must buy another piece of PGYTECH Landing Gear and check if problem will appear again. (from other supplier)

Does anyone have a similar problem ??

If you want to use those landing gear anyhow, then disable the "Landing Protection" setting in DJI GO.

When I'm landing with extended legs (drone hit the ground) - landing is not gentle...

When I disable Landing Protection - drone will still hit the ground...

Take picture of the sensors when landing gear are in place and post it.
I have used these landing gear for almost a year and newer have any trouble.

G_Sig Posted at 2018-7-25 10:23
Take picture of the sensors when landing gear are in place and post it.
I have used these landing gear for almost a year and newer have any trouble.

Earlier I used this landing gear about one year to, and newer have any trouble.
I changed the mavic and get new landing gear - and problems appeared.

I will try to get photo of issue - but it is a little bit dangerous - I can crash or loose the drone (try to run from me).
I know that the readings from ultrasonic sensors (after issue message) - are going crazy  (they changed even dron is in one place - didn't move).

Do You have the latest software in drone, radio and latest version of DJI GO 4 app ? (and You still fly with extended legs from PGYTECH ?)

fansf0765a77 Posted at 2018-7-25 10:30
Earlier I used this landing gear about one year to, and newer have any trouble.
I changed the mavic and get new landing gear - and problems appeared.

Just take the picture when drone is turned off and put it upside down. It's better just to see the bottom of drone.

My landing legs have never caused any problems. I have used some I have 3D print and some purchased in China. All you need to take care of is the rear leg is not in the way of the sensors below the bottom. Maybe you should try to reverse your back landings leg ?

And It is absolutely NOT necessary to turn off  "Landing Protection" in DJIGO4.

Regards Leif.

This is not my photo, but my legs are mount the same as in photo (they are not on reverse side)

fansf0765a77 Posted at 2018-7-25 10:30
Earlier I used this landing gear about one year to, and newer have any trouble.
I changed the mavic and get new landing gear - and problems appeared.

I'm not on newest FW on dron or controller but newest app.

@G_Sig - thanks for reply - I'm gona look for someone who have the latest software (maybe DJI have increased the sensitivity of the sensors or mess something in latest software).

Sensors have "bad readings" not from the beginning of flight - sometimes I can fly even 6-7 minutes without problems - sometimes I get problem after one or two minutes...

I flew in different locations - the same problem - it is not problem with location

Weird they show up in the DJI store.  See https://store.dji.com/product/pg ... ing-gear-extensions,

@fansf0765a77, I got to agree with on sensitivity.

The back legs can confuse the ultrasound sensors! there are two sensors: one emits the second reception! the waves emitted when returning to the receiver can be diverted from the rear legs and thus the receiving sensor sends random false information to the mavic flight controller ... briefly mavic thinks you are 3 meters from the ground .. suddenly at 5 meters from the ground by confusing the flight controller (by default, and the ESC Controller) for a slow and safe landing. The materials from which extensions are built can influence the operation of ultrasonic sensors (plastic type / composition)

but earlier everything was working perfect (when I was flying my first mavic pro platinum, and my first extended landing gears from PGYTECH - I've lost landing gears from PGY and next drop my mavic to the ground - I get new one from DJI).
So I bought PGYTECH landing gears again (first time was ok, so why not the second time).

But on my new mavic, with new firmware, with new landing gears - drone have ultrasonic errors when the legs from PGYTECH are mounted to drone.
Something is wrong (maybe I get legs with bent in the wrong direction (angle) - maybe they are from diffrent type of plastic, maybe rear legs are to long ? or DJI changed something in newest Mavic-s ?) Maybe new firmware causes that sensors are working stronger ? (and they see legs ?)
Manufacture date of my mavic is May 2018 - maybe one or two ultrasonic sensors are in angle position ? and they cath extended legs ?

Maybe all mavics manufactured from May 2018 will have the same problem with PGYTECH extended legs - I have contact with PGYTECH and we want to find out what's  going on.

Hi Lucas,

Thanks for using PGYTECH prodcuts, we appreciate your response.
This landing gear extension is a very hot sales product, have been sold out thousands with seldom such a problem.
However, we are very eage to find out the reason together with you.
Our aftersales manager will contact you soon today.

Regards

[size=14.6667px]Hi Lucas,

[size=14.6667px]

Thanks for using PGYTECH prodcuts, we appreciate your response.

This landing gear extension is a very hot sales product, have been sold out thousands with seldom such a problem.

However, we are very eage to find out the reason together with you.

Our aftersales manager will contact you soon today.

Regards

Hi Lucas,

Thanks for using PGYTECH prodcuts, we appreciate your response.
This landing gear extension is a very hot sales product, have been sold out thousands with seldom such a problem.
However, we are very eage to find out the reason together with you.
Our aftersales manager will contact you soon today.

Regards

Hello.

I want to say that PGYTECH send me brand new extended landing gears for free (for test) - I received landing gears few days ago.
Big Thanks to PGYTECH for sending me this legs !
Today I was testing them and...
I get the same issue...

Drone ultrasonic sensors gone crazy afrer few minutes of flight - I am on 9 meters and suddenly I see in DJI GO APP that my drone is at 0.2m !  (in fact, it is on 9 meters !) - no ultrasonic error message - but drone go up (because it thinks that is realy close to the ground) - When I push left stick down - drone don't want do go down - I must push it all the way down to bring him down - but then my drone wants to land
(enter the landing mode) - when it lands - he crash gronund hard (no slow descent).

I recorded my flights - I will publish the flights logs and movies - but I must copy them to my PC and cut them to show the right time (moments when You can see the issue).
Tomorrow I will try to make flights without any extended landing gears - I will try if I can get this issue without extended legs (but earlier was no issue when was no extra landing gears).

Have you observed you MP VPS in flight w/ out the landing feet?
Does it behave normally?

today I will make a flight without any extra landing gears -If issue will appears - tomorrow I will open the case and send drone to DJI (but earlier I didn't have issue without extra legs) - but I must try again to be sure

fansf0765a77 Posted at 2018-8-15 05:56
today I will make a flight without any extra landing gears -If issue will appears - tomorrow I will open the case and send drone to DJI (but earlier I didn't have issue without extra legs) - but I must try again to be sure

Have you tried recalibrating VPS with legs attached (I suspect it checks sonar at same time) ?

I'm after four flights today.

First flight - without any external legs - 15 minutes without any (even one, for a second or two) bad VPS measurement - (after this time) I landed and get ready for next flight (turn of the drone and add extra legs).

Second flight - after about two minutes of flight - first bad VPS measurement, two or three second of good VPS measurement, and again bad... few seconds later - I get message "Ultrasonic sensors error - Land immediately".  (I land and remove extra legs).

Third flight - about 6-8 minutes - no problems ! (after landing I add extra legs without turning off the drone).

Fourth flight - after about 2 minutes - bad VPS measurement (no message about ultrasonic sensor error - but sensor readings gone crazy (6meters, second later 0,2meters, 5meters, 0,1 meters...)

I don't know what's going on !

I will try to find somebody who have mavic pro near my location.

Tomorrow I will try send You a movies from today (I record them)

I don't want to send drone to DJI - because they can check it without legs and tell me that everything is ok...

Did you ever figure this out?    I'm getting downward sensor errors with my MP1 now and I'm using the same PGYTech landing gear.  I have two Mavics, and I haven't had any issues with one of them, but the one I've been flying  yesterday and today seems to be giving me errors at seemingly random times during my flights.   Very intermittent like yours.    Based on finding this thread, I'm going to try to fly tomorrow without them to see if the error goes away.

LP

LeafPeeper Posted at 6-10 17:00
Did you ever figure this out?    I'm getting downward sensor errors with my MP1 now and I'm using the same PGYTech landing gear.  I have two Mavics, and I haven't had any issues with one of them, but the one I've been flying  yesterday and today seems to be giving me errors at seemingly random times during my flights.   Very intermittent like yours.    Based on finding this thread, I'm going to try to fly tomorrow without them to see if the error goes away.

LP

Hi all
I have this landing gear on my MP1 with no problems, however make sure the rear legs are correct way round so as to be clear of the sensor. Worth a try.

LeafPeeper Posted at 6-10 17:00
Did you ever figure this out?    I'm getting downward sensor errors with my MP1 now and I'm using the same PGYTech landing gear.  I have two Mavics, and I haven't had any issues with one of them, but the one I've been flying  yesterday and today seems to be giving me errors at seemingly random times during my flights.   Very intermittent like yours.    Based on finding this thread, I'm going to try to fly tomorrow without them to see if the error goes away.

LP

Hi all
I have this landing gear on my MP1 with no problems, however make sure the rear legs are correct way round so as to be clear of the sensor. Worth a try.

PGYTECH Posted at 2018-7-26 23:02
Hi Lucas,

Thanks for using PGYTECH prodcuts, we appreciate your response.

I too have this problem.  My first Mavic Pro had zero problems (not ever), my 2nd Mavic Pro had zero issues as well.  My third Mavic Pro....cannot fly without turning off "Landing Protection" just as the OP experienced.  I conclude that the issue is with QC issues with Mavic Pro's sensors.  Mavic flies PERFECTLY without Landing Protection and instantaneously poor (stuck in hover, intermittently stops when going up/down, will only go slowly down, etc).  The annoying thing about turning off landing protection is you are prone to very hard landings if not careful.

USS Pretty-Bird (NCC-1702) Posted at 6-11 13:42
I too have this problem.  My first Mavic Pro had zero problems (not ever), my 2nd Mavic Pro had zero issues as well.  My third Mavic Pro....cannot fly without turning off "Landing Protection" just as the OP experienced.  I conclude that the issue is with QC issues with Mavic Pro's sensors.  Mavic flies PERFECTLY without Landing Protection and instantaneously poor (stuck in hover, intermittently stops when going up/down, will only go slowly down, etc).  The annoying thing about turning off landing protection is you are prone to very hard landings if not careful.

Well I flew tonight without landing gear and guess what?  3 long flights, no errors, and no funky VPS readings.   I agree it may be QC or tolerance differences between Mavics.   Maybe the sensors are aligned just right to interfere with the PGYTech landing gear on some.     I'm going to try some other gear and see what happens.

LP

LeafPeeper Posted at 6-11 15:20
Well I flew tonight without landing gear and guess what?  3 long flights, no errors, and no funky VPS readings.   I agree it may be QC or tolerance differences between Mavics.   Maybe the sensors are aligned just right to interfere with the PGYTech landing gear on some.     I'm going to try some other gear and see what happens.

LP

That is exactly the issue - QC and differences between mavics...while off topic- I've seen major issues such as range differences between Mavics (all things exactly the same).