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i Send Ticket to dji so we all have to do IT so they Work fast for a solution before crack Shell ...
Major Vibrations P3P
- Thread starter Static8
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alokbhargava
Premium Pilot
Every structure has a natural oscillation frequency (critical frequency) and that should not fall within the operating range. If it happens then there could be a resonance and we will see structural failures.
Glad I found this thread. It seems it's not just limited to P3P. I don't know how to put up a link to another thread, but do a quick search for "Weird Noise" and you'll find a thread on the P3S side. Seems like the same issue.
I've got a P3S (one month old, no crashes, nothin...) here's my post from the other thread:
I had a very similar experience this weekend. Took the phantom on a road trip. Updated firmware, calibrated compass, even did the imu cal. Coldish day (30F) light wind. Noticed on initial takeoff that I had the same shake you describe (never had before). Landed and did another compass cal. Same thing on next takeoff, but elected to push it a bit. Flew it close (no more than 1000' horizontally and 200' vertically). After about 15 minutes, I brought it back on close, and the shake was gone.
I flew about 5 other flights and they were all the same.
I'll check the mount. Any other ideas?
I've got a P3S (one month old, no crashes, nothin...) here's my post from the other thread:
I had a very similar experience this weekend. Took the phantom on a road trip. Updated firmware, calibrated compass, even did the imu cal. Coldish day (30F) light wind. Noticed on initial takeoff that I had the same shake you describe (never had before). Landed and did another compass cal. Same thing on next takeoff, but elected to push it a bit. Flew it close (no more than 1000' horizontally and 200' vertically). After about 15 minutes, I brought it back on close, and the shake was gone.
I flew about 5 other flights and they were all the same.
I'll check the mount. Any other ideas?
Yes I agree which makes is likely the problem with new firmware not giving enough juice during hover mode
Can you keep us posted on a fix If you find one,I'm having the same vibration on my p3s. Thanks
This is really painful to admit, but anyone could have done it: I put new props on "my baby", and spun them down until they reached bottom, then didn't touch the bird for a few days. I certainly MEANT to tighten the props... BUT I TOOK OFF WITH THEM AS LOOSE AS IT SOUNDS AS THEY WOULD BE ABOVE. GO DJI! I flew for 10 minutes. High to low, a couple hundred yards away. THEN, got a RED WARNING about SEVERE VIBRATION, something worse like a prop strike, THEN: ENGINE AT IDLE. WTF? I was looking at the P3 at this point. It looked OK, I was afraid to barely move the controls. I settled into some grass. Uneventful -- except for the start of the "Drone Justice..." drama. Which wouldn't have happened except for this. :-(
I got in my condo, and had it idling. No binding, I was just about to hover when A BIG VIBRATION STARTED. AN UNBALANCED CONDITION TURNED VIOLENT BECAUSE I THINK IT WAS ASSUMING A "RESONANT" FREQUENCY. AMAZINGLY VIOLENT. I GRABBED A LANDING GEAR LEG -- NOT EVEN HARD -- AND IT ABRUPTLY QUIT (Damped out resonance)! Was I puzzled! Then I checked the props tightness, and they weren't! BUT, one HELL of a lot tighter than when I took off! ZERO tightness then L(cry)OL. DJI's self tightening props saved me from myself. USE CHECKLIST.
SO OBVIOUSLY THIS HAS BEEN ASKED, BUT I THOUGHT I'D THROW IN AN (EMBARRASSING) PERSONAL EXPERIENCE: WERE YOUR PROPS FIRMLY HAND SNUGGED DOWN? I'M ASSUMING THAT THE GIMBAL VIBRATION WAS AN EFFECT, AND NOT A CAUSE. MY EXPERIENCE WITH NOT DOING SO WAS A SEVERE VIBRATION, OBVIOUSLY AMPLIFIED BY A RESONANT CONDITION, THAT I THINK DID DAMP OUT IN FLIGHT -- I DON'T THINK MY ENGINE WAS IDLING, BUT THE RED WARNING DIDN'T GO AWAY. AND THE SEVERE VIBRATION GOT RECREATED ON A COFFEE TABLE IN MY LIVING ROOM. A RESONANT SITUATION, BECAUSE JUST PRESSURE ON A GEAR LEG STOPPED IT. NO PROBLEMS SINCE. AND I HAVE A CHECKLIST, AND "INSURE PROPS ARE SNUG IS ON THE TOP"!
PS I'm assuming my loose props were mimicking a severe out of balance condition at times. So an out of balance prop would be a potential underlying cause but to get as severe as you talk about, and what I saw close up, it seems like it would have to be WAY out of balance. I hope something here was useful information for you (or others).
I got in my condo, and had it idling. No binding, I was just about to hover when A BIG VIBRATION STARTED. AN UNBALANCED CONDITION TURNED VIOLENT BECAUSE I THINK IT WAS ASSUMING A "RESONANT" FREQUENCY. AMAZINGLY VIOLENT. I GRABBED A LANDING GEAR LEG -- NOT EVEN HARD -- AND IT ABRUPTLY QUIT (Damped out resonance)! Was I puzzled! Then I checked the props tightness, and they weren't! BUT, one HELL of a lot tighter than when I took off! ZERO tightness then L(cry)OL. DJI's self tightening props saved me from myself. USE CHECKLIST.
SO OBVIOUSLY THIS HAS BEEN ASKED, BUT I THOUGHT I'D THROW IN AN (EMBARRASSING) PERSONAL EXPERIENCE: WERE YOUR PROPS FIRMLY HAND SNUGGED DOWN? I'M ASSUMING THAT THE GIMBAL VIBRATION WAS AN EFFECT, AND NOT A CAUSE. MY EXPERIENCE WITH NOT DOING SO WAS A SEVERE VIBRATION, OBVIOUSLY AMPLIFIED BY A RESONANT CONDITION, THAT I THINK DID DAMP OUT IN FLIGHT -- I DON'T THINK MY ENGINE WAS IDLING, BUT THE RED WARNING DIDN'T GO AWAY. AND THE SEVERE VIBRATION GOT RECREATED ON A COFFEE TABLE IN MY LIVING ROOM. A RESONANT SITUATION, BECAUSE JUST PRESSURE ON A GEAR LEG STOPPED IT. NO PROBLEMS SINCE. AND I HAVE A CHECKLIST, AND "INSURE PROPS ARE SNUG IS ON THE TOP"!
PS I'm assuming my loose props were mimicking a severe out of balance condition at times. So an out of balance prop would be a potential underlying cause but to get as severe as you talk about, and what I saw close up, it seems like it would have to be WAY out of balance. I hope something here was useful information for you (or others).
Possibly I should have replied, but put a post at the very end of this thread. I saw something virtually identical caused by...loose props...don't snicker too loud please. Just make sure yours are nice and hand snugged down.
The remark below about every structure having a resonant vibration, I knew from vibration tests we do to circuit boards, and complete box assemblies in the Defense Electronics Business. Mechanical Engineers really sweat that stuff. I shouldn't have assumed it was common knowledge.
I think my loose props made one of them end up in a very out of balance condition, then a juicy resonant frequency was found -- a doozy -- and WOW! I damped it out by just lightly grasping a gear leg. It was just a thought. An easy way to get a prop WAY out of balance. A modestly out of balance prop, resonating that violently... I'd hope there would be margin designed in. But that's all I know!
Great information. I mentioned resonance as a big contributor, but neglected to mention this. Which can mean that instead of the horrible vibration encountered here, it could be just severe enough to cause structural damage, and probably eventual failure. In a lot of applications, it can be a shortened lifetime of a structure which could even be long enough so that a mechanism like this isn't suspected. Especially if you aren't familiar with the concept, much less do vibration testing like we did with a lot of Hi-Rel Military Boxes and CCAs at Harris Corp.
So with this reasoning, it may be possible for a perfectly good flying P3 to reach this point created at a given RPM and crash without the pilot knowing that the vibration occurred. -- especially if the aircraft were some distance away or out of sight when it occurred???
Boy, I'd sure like to think the DJI engineers knew about this stuff, to the point of experimenting with unbalanced props across the RPM range. Could you have two out of balance props, that are effectively additive in their vibration contributions, and enter a realm where DJI didn't go? Would that be the same as just one out of balance prop/hub twice as bad?? I'd hope with such a big company, producing so many units, with lots of smart electrical AND mechanical engineers, that your scenario (VERY possible), wouldn't be present in a DJI late model Phantom without a bad screw up at the design level. Oh, that's code for: "I doubt it, but it's possible, but DJI probably looked for such possibilities when they designed the bird. But it still scares me." LOL I'm an electrical guy. Mechanical Engineering opinions are very welcome!
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great thread so far ...
ive tried posting the question on dji forum but so far its just got ignored.
ive tried posting the question on dji forum but so far its just got ignored.
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Following this thread, I just got my bird back yesterday from dji for the signal loss problem. (no explaination of what they did and even called and they cant tell me.) I flew one battery last night and no signal loss what so ever. I was going to upgrade last night but decided to wait for a few more flights and glad I did after reading these posts.
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no props no no just try this advice from EU support and get ready to fly [emoji39][emoji122]
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This is good to hear.
So it's the imu calibration making the difference it seems.
I can't see how a downgrade in firmware and immediate upgrade will make changes that are not overwritten back when you upgrade.
So it's the imu calibration making the difference it seems.
I can't see how a downgrade in firmware and immediate upgrade will make changes that are not overwritten back when you upgrade.
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