Bird will always shake while descending straight down, this is a VRS - type wobble. Can't be avoided, you have to have a little forward or sideways speed to avoid the prop wash and maintain stability while descending fast. ( > 1-2 m/s descent speed)
P4 Firmware v02.00.0106 Released (2017-07-06)
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Bird will always shake while descending straight down, this is a VRS - type wobble. Can't be avoided, you have to have a little forward or sideways speed to avoid the prop wash and maintain stability while descending fast. ( > 1-2 m/s descent speed)
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I agree, that's why we never start descending a helicopter straight down , always do it when moving slightly forward until last minimum to avoid that bumpy prop wash!
Your missing the point, I have flown this drone for 12 months now and it's never reacted like this, everything is messed up with that latest firmware update.
I am not the only one, if your drone is fine then that's good news, but mine is terrible now no matter what I do, I have had an independent experienced drone flyer check things out and he is in total agreement, things aren't right.
I am not the only one, if your drone is fine then that's good news, but mine is terrible now no matter what I do, I have had an independent experienced drone flyer check things out and he is in total agreement, things aren't right.
You have also missed the point. The P4 has always had a VRS wobble in S mode if you tried to go max speed straight down. It's minor (in that it won't drop the AC from the sky..), but it's there. The guy I quoted sounded like he had a VRS issue, since he was talking about descending...
The new 2.02.0106 wobble is happening in all flight conditions, particularly bad when travelling downwind.
Not just bumpy, potentially lethal if you get a ring formed
I agree that mine shook before but its worse now. I can hear a longer more aggressiveness cycle of pulses from the motors during descent causing it to flutter like a falling leaf rather that a mild oscillation as before. If I understand how these things work there would be a loop running running in the computer checking if it's descending too fast or slow the applying the correct output to the motors to get within parameters. It seems they've changed the duration of the loop and more output is having to be applied per loop, longer wait between loops or other checks being run in between maybe?
Sport mode and P mode FWIW.
The loop times will not have changed, what will have changed will be the amount of pitch correction the software applies through the ESCs per loop cycle. Why? could be any number of things. Typo causing some smoothing expression to be left out or errored. Engineer winding up the rates on an expression, fixing one problem somewhere else but causing WobbleDrone. Bad calibration function causing otherwise spot on rates to perform poorly due to 'garbage in, garbage out'....
Fair enough, my understanding of micro controllers is limited but my ears don't lie. Something with how the loop of checks and balances is applied on full down stick descent has changed.
Yes, I understand this. What I am experiencing is not VRS wobble. It's more violent and also happens when descending while moving.
You have also missed the point. The P4 has always had a VRS wobble in S mode if you tried to go max speed straight down. It's minor (in that it won't drop the AC from the sky..), but it's there. The guy I quoted sounded like he had a VRS issue, since he was talking about descending...
The new 2.02.0106 wobble is happening in all flight conditions, particularly bad when travelling downwind.
Not just bumpy, potentially lethal if you get a ring formed
Hi Goof
Your assuming I am descending in sport mode, I can confirm that I wouldn't even risk that behaviour is sport mode as my aircraft would probably crash and be destroyed.
My experience is in normal P mode when descending.
Been on phone to DJI again today, they are still working on new firmware, we might get sorted out by winter at this rate.
Mine too, before the update it descended perfectly, now it looks very unstable.
I am very aware of VRS from flying my P2 vision+ and in those days always took care and moved forward and back in descent. One of the joys of the P4 was I thought that VRS was a thing of the past(For quads , not for Helicopter pilots), and I have got used to descending without any special care. I think they angled the P4/3 motor mounts which altered the prop wash pattern and made it more stable.
Everything else on the upgrade is reasonably OK, apart from reduced speed in sport mode, which is not really a problem for me, and possibly reduced flight time.
Still wish I had not updated, as I do not really use the enhanced flight modes.
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For the sport mode speed, check if the enhanced flight modes button still appears when in sport mode. If so, you need to reset the flag for advanced modes in settings. Mine had that issue until I unchecked and then re checked.
Update: Spent about an hour with DJI support last night, they want me to send my drone in so they can do the proper downgrade, etc. I declined as I have heard the horror stories of other DJI “Repair” experiences. I reset factory settings, refreshed the firmware using DJI Assistant, then calibrated IMU, Compass, and Gimbal. Went for a 15 minute test flight this morning, no problems with shaky flight, the drone was fine performing various agile maneuvers. The signal loss seems to have improved slightly, but as I approached 1200ft away, the signal dropped. I did not experience the wacky gimbal behavior like I had during past signal drops though. Lets hope DJI gets that patch going quickly...
Thats is apparently their script. Reset this calibrate that. Send it in for repair. Pretty bad service.
I've seen several, including mine. Videos are available on youtube showing others with the same problem and slight variations therreof with the gimbal.
Those of us who updated and ended up with wobbly drones have definitely been served with garbage in. I just don't want $1000 splattered on the ground and DJI tell me it's my fault. My P4 is in transit to DJI in CA right now.
I hope they fix it. If they call me and tell me I have to pay for 'whatever' when it's 2-3 months old, they can send it back and I'll turn it over to the courts. I don't trust DJI service at all.
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Has anyone crashed as a direct result of the FW? Jesus you sound like one of them pilots that say they've spotted a drone, you know the ones that have time, lots to prepare for landing while having a nosey at 3 oc through the window [emoji849] relax and have faith
No one that I know of has crashed one- yet. Most who have the problem did what I did and grounded their drones. I had a FW update 2 years ago on a P3A and it went screwy after an update, lost connection and it dropped from the sky into a hayfield. DJI never would explain to me how it happened, what happened, but I ended up paying for the repairs. I DEMANDED an explanation from DJI, their answer was 'pay up or we return you a dead drone'
AKA F-U.
I have absolutely no faith in DJI now and will not be buying anything they make again. The biggest problem I've seen with DJI drones is their firmware- their programmers. The aircraft overall are excellent. But if you can't put them in the air because they're unstable and I know since I've had one drop from the sky before, they're dangerous.
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