DJI Announces 5.21 Beta Firmware

A

atver

Member
Yesterday, DJI made announcement in RC Groups Forum for solution to height dropping during flight but didn’t post in this forum. Here’s their announcement;

Dear DJI WKM owners:

Recently we had received some feedbacks about WKM height dropping during flight, some specific customers also encountered the problem of height dropping during hovering, actually through a large number of tests, the reason of theseproblems has been identified.

The following are the specific reasons:
Due to the imbalance of the propellers or deviated installing position of the IMU, which lead to one side of the IMU stay right against the fuselage. The excess vibration of fuselage transmitted to the IMU, make it cannot work normally.
We tried to balance the propellers and covered the side of the IMU with somedampers on 10 aircrafts which have the height dropping problems, and finallythe height dropping problem disappeared.

So here are our solutions:
First of all, we strongly recommend that users could DIY some damping schemes,such as balance the propellers or add some damper around or under the IMU.These will probably relieve the problem. Some customers had already verifiedit.
In addition, DJI has developed the firmware 5.21 beta (attached is the updatesteps), when the throttle has been pushed up to more than 85%, the dropping problem will be gone, this will save you from some risks, and the feedback from the testing users were satisfied.

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ChrisViperM

ChrisViperM

Active Member
Thanks for posting the info....one thing I could never get into my head: why did the make that cut-out - where the IMU is looking out of the frame - so damn tight....it's a pain in the butt to mount the IMU in a way that it doesn't touch the top-plate of the frame....not even 1 mm space all around.

Chris
 

A

atver

Member
And-- another interesting comment from DJI is that they now recommend adding some damping material arround or under the IMU. They were always opposed to mounting the IMU on damping material. This was a surprising recommendation.

Jim
 

H

hover.ch

Member
If DJI officially announces a fix version for an obvious issue I would expect them to also announce it in this forum.
Have I missed someting?
 
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H

hover.ch

Member
Yes! Reading an announcement about multiple MRs loosing height in a more or less uncontrollable way sounds rather frightening. Definitively something important to know.
 


hjls3

hjls3

Member
Did anybody give this a whirl today? I just went to 5.20 last week from 5.16. have to admit my IMU has made its way to touching the side of the top plate. Not sure how and when, but it has. I guess they are suggesting dampning material wedged around IMU in the too small cutout of the S800 top plate?
 


ChrisViperM

ChrisViperM

Active Member
Dear DJI WKM owners:

Recently we had received some feedbacks about WKM height dropping during flight, some specific customers also encountered the problem of height dropping during hovering, actually through a large number of tests, the reason of these problems has been identified.

The following are the specific reasons:
Due to the imbalance of the propellers or deviated installing position of the IMU, which lead to one side of the IMU stay right against the fuselage. The excess vibration of fuselage transmitted to the IMU, make it cannot work normally.
We tried to balance the propellers and covered the side of the IMU with some dampers on 10 aircrafts which have the height dropping problems, and finally the height dropping problem disappeared.

So here are our solutions:
First of all, we strongly recommend that users could DIY some damping schemes, such as balance the propellers or add some damper around or under the IMU. These will probably relieve the problem. Some customers had already verified it.
In addition, DJI has developed the firmware 5.21 beta (attached is the update steps), when the throttle has been pushed up to more than 85%, the dropping problem will be gone, this will save you from some risks, and the feedback from the testing users were satisfied.
Click to expand...

That's the statement from the RCG site, and its the biggest joke DJI ever produced:

" ....such as balance the propellers or add some damper around or under the IMU..." You can search the net for as long as you like, you won't find a statement like this ón any flight control manufacturers website, regardless if Single Rotor helis or Multis. All of them tell you to use a specific tape, 'cause there is thousands of different damping pads out there, but most of the time it's only one that works....millions of posts from guys looking for a replacement for the original dampening tape. The cut-out for the IMU is so tight (on S800's), there is no space for additional dampening....whatever you use, it will make the space even more tight and make things worse. From the statement it's not even clear if this problem is only on S800 or on other rigs as well....so how are people doing the "damper arround" if they mounted their IMU on a fifferent bird free standing ...but since this all won't work, we still can balance the props instead ????? :livid:

Props should (and will by the majority of our forum members) always be balanced, and the only immediate work-arround would be if they tell us to take a Dremel tool, make the cut-out bigger and tell us EXACTLY which dampening pad to use....and fix this small cut-out in their production line.


I really try not to ***** about DJI (as I did a lot in the past), and they have some great products (if they work), but their attitude sometimes makes me want to strangle someone.....grrrrrrrrrrrrrr :livid:


Chris
 

H

hover.ch

Member
To be honest, I can not even understand their language...
First of all, we strongly recommend that users could DIY some damping schemes, such as balance the propellers or add some damper around or under the IMU.

What do they mean by DIY (do it yourself?), what are damping schemes ...?

BTW: Is this a general issue or is it bound to a specific firmware version?
 

ChrisViperM

ChrisViperM

Active Member
What do they mean by DIY (do it yourself?), what are damping schemes ...?
Click to expand...

Yes...it means Do-It-Yourself....and it means that they have no clue how how this problem can be solved ...your DIY approach might work, or not...

BTW: Is this a general issue or is it bound to a specific firmware version?
Click to expand...

In general, all kinds of stabilisation controls where gyros and sensors are involved, should not be touched by anything (like cabels or frame) since this would falsify the output of the sensors....this is a hardware related issue and any manual of any flight control or stabilisation system . would state: Don't let the stabi be touched by anything....It is possible to somehow adress this into the firmware, but it would have a negative effect somewhere else.....


Chris
 

H

hover.ch

Member
Let me ask once more: Is this issue related to a specific firmware version, e.g. 5.20 ?

How else could it be that some tenths (or hundreds?) of customers have appoached the same issue now (and not erlier / over time)?
If I stick to 5.16 - and I fortunately do - I am safe?
 

A

atver

Member
There have been issues with DJI’s software since version 5.14a. If you go to DJI’s firmware update page http://www.dji-innovations.com/products/wkm-waypoint/downloads/ you’ll see they removed all their updates below 5.20 down to version 5.14. I experienced my CX-4 falling from the sky at version 5.14a. Since that time I’m not updating until DJI can get their firmware stable. If you do a search, you’ll find various version after 5.14 with issues. Hope this helps you.

Jim
 
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D

Dewster

Member
I've always mounted my IMU topside and just used a canopy cover to protect it. My wiring is between the two metal plates on my F550. Despite some of the grumbling, I'm pretty happy with DJI's system. I use 5lb mounting tape to secure the IMU. I'm not sure if it provides and damping effect, but I haven't had issues.

DJI's F550 and F450 frames good. The metal plates are great for the weight that I see these crafts being loaded up with. I don't think you have to worry about an arm snapping off mid flight.

I guess people have had issues recovering form losing altitude. I'm just wondering what'll happen when you push it past 85% on the throttle. I guess it'll be like opening up the flood gates.
 

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