Naza rapid ascent with quick red LED

[StarterH]

Hey all,

So I've got my first multi build under my belt with a stock DJI F550 kit (Motors, ESCs, Props), NAZA-M (without GPS), Turnigy Nanotech 6000mAh Lipo, and Futaba T8J.

It's been really great so far, and I've had 5 successful flights with it, only one major crash but nothing broken.

HOWEVER:

Every once in a while I will bring the throttles up gently to ~55% and the aircraft will shoot up 10-15 feet. It sounds like the motors are hitting 100% very suddenly. Typically, if I drop the throttles back below 50% it will even out and start descending slowly. One time, my only crash, it shot up 40 feet and a gust of wind pushed it back over my house where I couldn't see it anymore. I didn't think to hit the failsafe, instead I cut the throttles to 0 and it crashed in the street in front of my house. I was flying it around in my back yard yesterday, and I noticed that every time it has that behavior, the LED goes from blinking a steady yellow to a rapid red. I've only had it happen in attitude mode, but my lack of experience makes me nervous to just fly in manual all the time.

I've been reading up in the forums about all the potential causes. I have placed black tape around the outside of the NAZA and calibrated the IMU and my sticks several times. I've set my gains at 170, 170, 170, 170 and attitude at 80,80. My NAZA firmware is up to date, 2.02.

Any wisdom for a noob like me?

 

[Dewster]

Make sure that you don't cover any small holes in the IMU with tape. I think it blocks the barometric sensor. That could result in altitude changes that you are experiencing. I think the best thing to do is place a cover or a dome over your Naza (if its topside). That will help shield your craft from sun, damage in the event of a crash, and shield (not block) direct exposure to wind.

You will need to inspect the wiring after a crash. Hopefully the internal components of your Naza are not damaged.

The GPS feature really helps to keep your craft planted in the wind. Flying in Attitude mode is like skating on ice. You'll need some room to practice. GPS will be a lot easier to learn on.

 

[StarterH]

Thanks for the reply Dewster!

The Naza is in the interior build space, so it's pretty well protected. I did take a look at my wiring after the crash, there is no visible damage to the connections and I reseated the wires going from ESC to Naza and receiver to Naza while checking for bent or damaged pins.

Thanks for the tip about making sure the holes aren't covered. I'll investigate that, but I doubt that is the cause because my aircraft was doing the rapid ascents before I put the tape on in the first place.

Any thoughts on the switch from steady yellow to rapid red on the LED? I looked on the DJI support site, didn't see anything all that useful. It's an indication of low voltage (battery is fine) or an "other error".

 

[Olemil]

Thanks for the reply Dewster!

The Naza is in the interior build space, so it's pretty well protected. I did take a look at my wiring after the crash, there is no visible damage to the connections and I reseated the wires going from ESC to Naza and receiver to Naza while checking for bent or damaged pins.

Thanks for the tip about making sure the holes aren't covered. I'll investigate that, but I doubt that is the cause because my aircraft was doing the rapid ascents before I put the tape on in the first place.

Any thoughts on the switch from steady yellow to rapid red on the LED? I looked on the DJI support site, didn't see anything all that useful. It's an indication of low voltage (battery is fine) or an "other error".

Just curious, did you calibrate your battery voltage in the Naza software to match your actual battery voltage? Mine was off quite a bit when I first set up my Naza, might be something to check as far as the low voltage red light is concerned (if you haven't already that is).

 

[StarterH]

Thanks for the tip Olemil! I'll look in to that. I did ballpark it when I first set it up, but it's something I haven't looked at since, so worth investigation. I'll let you know what I find!

 

[b0nafide]

Check your props. I observed the same rapid ascent from my F550 and once I changed my props (brand new balanced) the bouncing went away.

 

[StarterH]

Check your props. I observed the same rapid ascent from my F550 and once I changed my props (brand new balanced) the bouncing went away.

Did you go with standard DJI props, or upgrade to some graupners?

 

[StarterH]

OK, have some news to report.

I checked a fully charged battery pack against what the Naza was saying, it was reading .4 volts low so I calibrated it to the 12.6 that I had charged to and I no longer get the low voltage warning every time it ascends. However it is still ascending under attitude mode. Manual flies pretty nicely, if I had any experience and felt comfortable I'd just do that.

Next step, ordering some graupners and taking off the bottom PCB so I can inspect the tape job.

EDIT: Also, going to fiddle with the throttle gains some more.

 

[StarterH]

Just spoke with Patrick at AMP, he suggested I lower my gains to 130 130 140 140 130 130. Tried that, to no avail. Will put it up in the air with the gains on remote so I can adjust, see if fine tuning that by itself has any effect.

Not really excited to send it back, but kind of at a loss.

 

[helloman1976]

Your attitude gains are WAYYYYYYY too low which is why in attitude is where the problem is occurring. The attitude gains are what tells the Naza how quickly to respond to your commands in attitude mode and if they are too low it'll cause major delays only to follow-up suddenly. I have mine at 165,165,170,170 and attitude at 165/165. If you have them at 80/80, that's way too low. The first 4 you had before are probably fine.

The blinking red lights come on when you hit your RED AREA of your battery calibration section. When you hit that voltage you'll see your red warning lights on your Naza start to flash rapidly and it'll also remove some power from you by moving the center of the throttle stick up so you can "feel" it enough to know it's "time to land". When you see the rapid red lights the Naza is basically telling you you've hit your safety voltage and in the manual it tells you that it tries to make you land. I have basically disabled mine now that I have an OSD that shows me my on-screen actual voltage.

 

[tugboat]

StarterH,
I could not agree more with helloman1976, the gains 80/80 look to low, try his and they will be very close to what you need, also Dennis Baldwin has a great you tube video on the voltage protection set up.
Did you apply the black tape to the fc yet??
Some will put it on both sides (I did) then when I moved my fc to the top plate I had to add tape to the top of the fc as she started the classic up and down.... extra tape was a instant cure.

 

[StarterH]

Thanks for the responses! I'll see what fiddling with the gains does for me as soon as I get the F 550 put back together. I had to take the top plate off to check the black tape situation, and I'm remounting it with some double sided mounting tape. The stuff that came with the FC had a little too much wiggle for me.

Also, have the GPS add-on coming from AMP. Hoping that will help as well.

 

[helloman1976]

Thanks for the responses! I'll see what fiddling with the gains does for me as soon as I get the F 550 put back together. I had to take the top plate off to check the black tape situation, and I'm remounting it with some double sided mounting tape. The stuff that came with the FC had a little too much wiggle for me.

Also, have the GPS add-on coming from AMP. Hoping that will help as well.

The GPS unit will only help you hold your position, track in a straight line and enable the return to home feature given your radio supports failsafe. You FC should not move at all and in a perfect world should always remain pointed straight ahead and never move a bit. The Naza is prone to vibrations in attitude/GPS hold modes but not so much in manual. I mounted mine with double sided tape and then zip-tied it to the frame through a loop in the mounting plate. Hope you get it worked out.

 

[StarterH]

Ok, GPS came in and I got it installed. Still no fix for the altitude issues. I have taped the sides and top of the FC, my gains are all at 165. I put the throttle gain on remote, and tried settings between 90% and 300%, nothing seemed to fix the issue.

So, here's a link to a video I filmed in my back yard of what it's doing. Hopefully one of you has some ideas!

https://dl.dropboxusercontent.com/u/32233941/Video Apr 11, 6 50 48 PM.mov

 

[helloman1976]

Ok, GPS came in and I got it installed. Still no fix for the altitude issues. I have taped the sides and top of the FC, my gains are all at 165. I put the throttle gain on remote, and tried settings between 90% and 300%, nothing seemed to fix the issue.

So, here's a link to a video I filmed in my back yard of what it's doing. Hopefully one of you has some ideas!

https://dl.dropboxusercontent.com/u/32233941/Video Apr 11, 6 50 48 PM.mov

So explain to me what we are seeing in that video. Is it doing that by itself? If so and you have applied the black electrical tape to both sides then you may have a defective unit. It's awfully shaky too and I'm wondering if it's suffering from vibrations. If the FC is vibrating it will have a hard time maintaining control. Can you put up some pictures of how you have everything setup? Some close-up shots? I'd like to see how you have everything setup.

1) Did you calibrate the ESCs individually one at a time?
2) Did you calibrate the controller in the Naza?
3) Put pictures up, close ups, of the entire system.
4) Are those stock motors and ESCs? DJI motors and ESCs? If not, what are they?
5) Did you update the Naza flight controller to the latest version of software?

Let me know and we'll go from there.

 

[tugboat]

You can get the rapid red VU flash when your battery is getting NEAR the threshold for low voltage protection and the motors are pulling hard (wide open) also a cheap battery or a battery with a low c rating or a c rating that is inflated....
As for the rapid ascent around 50% thro. the only thing I can think of is if there is expo on the thro. channel but it is put in as a negative number (easy mistake) and not a positive number this will have the same effect as what your seeing happen.
You could bring up the Tx monitor screen on the Tx and move the thro. to see if it jumps around 50% also try it in the assistant and see what the assistant shows.....

 

[StarterH]

So explain to me what we are seeing in that video. Is it doing that by itself? If so and you have applied the black electrical tape to both sides then you may have a defective unit. It's awfully shaky too and I'm wondering if it's suffering from vibrations. If the FC is vibrating it will have a hard time maintaining control. Can you put up some pictures of how you have everything setup? Some close-up shots? I'd like to see how you have everything setup.

1) Did you calibrate the ESCs individually one at a time?
2) Did you calibrate the controller in the Naza?
3) Put pictures up, close ups, of the entire system.
4) Are those stock motors and ESCs? DJI motors and ESCs? If not, what are they?
5) Did you update the Naza flight controller to the latest version of software?

Let me know and we'll go from there.

Helloman, thanks for your help! I'll post some pics in a bit, but first some answers to your questions

The video is what the aircraft does when it's at 50% throttle on the stick. No input from me at all. It was in GPS mode.

I'm not exactly sure what you mean by calibrating the ESC's, so probably I haven't done that. I did ensure the motors were rotating the correct direction.

I calibrated both the IMU and the sticks on the NAZA itself, multiple times.

I'm using stock motors and ESC's

I'm on 2.02 of the firmware.

Tugboat,
The red flashing has been dealt with by calibrating the voltage sensor on the NAZA. Here are my settings for the throttle channelView attachment 11050

 

[helloman1976]

Helloman, thanks for your help! I'll post some pics in a bit, but first some answers to your questions

The video is what the aircraft does when it's at 50% throttle on the stick. No input from me at all. It was in GPS mode.

I'm not exactly sure what you mean by calibrating the ESC's, so probably I haven't done that. I did ensure the motors were rotating the correct direction.

I calibrated both the IMU and the sticks on the NAZA itself, multiple times.

I'm using stock motors and ESC's

I'm on 2.02 of the firmware.

Tugboat,
The red flashing has been dealt with by calibrating the voltage sensor on the NAZA. Here are my settings for the throttle channelView attachment 14075

The ESC have to be individually calibrated using whatever is says in their manual. If they are stock ESCs they probably come calibrated. I'd say you have a defective unit and you need to return your FC to have it repaired. I've never seen that before but I'd be really curious to see your setup so we can see what's going on here. Mine did that and I put black electrical tap on the sides and it was immediately cured. Man...I'm stuck on this one...make sure the FC isn't getting a lot of vibration. Do you balance your props? Hmmmm.... I mounted my FC with double sided tape and then tied it down with a couple of zipties.

 

[StarterH]

Here are some close ups: View attachment 11051
View attachment 11052
View attachment 11053
View attachment 11054
View attachment 11055
View attachment 11056

What else do you need to see?

 

[StarterH]

The FC is mounted with double sided tape on the bottom, I used the 3M clear 2lb tape. I'll try the zip ties as well.

Ordered a prop balancer. I'll take off the props and see if I have a bent shaft or something as well.

After that, I guess I'll just have to send the FC back. That sucks, if I get to that point.