The graph attached is from my last flight an hour or so ago.

I have drawn a line across the low point of the first dip in throttle/revs.

Note that the revs have dropped well below normal for that throttle position and the second dip has deviated even further from normal if you take the extreme left hand throttle/revs readings as normal.

My question is does anybody know if there is a parameter setting to tighten this deviation up?

KK.

FF, motor/esc temps were normal

6:45am down on the farm.

Mild wind but it did not interfere with a very successful test flight in Atti mode.

I am still being troubled by that throttle problem occasionally but not to any great extent.

On one occasion it just simply lowered itself on to the ground while I was hovering at about 3 meters. Weird!

Anyway all I have to do now is learn to fly the old girl.

I am still making the occasional silly mistake and chopping the throttle and dumping it on the ground when in a panic situation. Unlearning 50 years of fixed wing throttle response is not easy, but I am getting there. I remember going through this back in 1972 when learning to fly helicopters. Same story, in panic mode push the throttle to full....... Not easy.

So there you have it.

Do I dare give myself another promotion?

I will leave to you blokes to decide this time.      

KK

The Naza low voltage protection is 2-level, with the 1st level giving you a flashing red LED and 2nd stage causing the craft to simply land. Have you done the calibration of the voltage settings in the GUI? May be a cause of IT landing without your commands

(25-Sep-2017, 12:02 AM)RENOV8R Wrote: The Naza low voltage protection is 2-level, with the 1st level giving you a flashing red LED and 2nd stage causing the craft to simply land.  Have you done the calibration of the voltage settings in the GUI?  May be a cause of IT landing without your commands

Thanks Reno. Yes I have and am quite familiar with the voltage warnings.

This problem is something quite different.

For example this morning I was hovering early in the flight on fully charged batteries and it started to sink. I started correcting with the throttle stick but it just kept sinking and when I got to full throttle it started climbing again. However by that time it had actually touched down.

The rest of the flight went by perfectly normally.

The other thing I notice in Atti mode is at take-off the throttle feels non linear. As I advance the throttle slowly the reves drop a little at mid throttle and then pick up again but at nearly full throttle. Whereas in manual mode the throttle is linear and does not exhibit the same loss of power thing.

Apart from this problem the Naza is working very well and is very easy to use. Wooden It is now flying very well and getting easier to fly with every flight.

KK

Down on the farm and a lot of flying.

Now that the Naza is close to being correctly tuned I find that Wooden It can handle a fair bit of wind.

Also I think that the throttle thing is tied up with how aggressively I advance the throttle. If I push the throttle straight to full the revs do not vary and throttle response is quite linear. Advancing the throttle slowly results a a non linear throttle response.

Not sure why but I am satisfied that is the explanation.

So things a moving slowly for sure but in the right direction.  

KK

(26-Sep-2017, 08:52 AM)Keyboard Kid Wrote: Advancing the throttle slowly results a a non linear throttle response.

I could somehow understand if that was noticeable only on take-off, but mid-air it seems weird, especially when you're high enough to be out of ground-turbulence... could it have to do with barometer doing weird things maybe (if it's enabled at all) ?

Either way, what about another promotion?

(26-Sep-2017, 07:07 PM)fftunes Wrote: I could somehow understand if that was noticeable only on take-off, but mid-air it seems weird, especially when you're high enough to be out of ground-turbulence... could it have to do with barometer doing weird things maybe (if it's enabled at all) ?

Either way, what about another promotion?

Mmmmmm.......

Let me see now    

Knows a lot more stuff about stuff but still does not know all of the right stuff.

How does that fit FF?

I wish I knew more about the Naza stuff, but it's closed source and proprietary and that makes my interest level close to zero.

(27-Sep-2017, 07:09 PM)unseen Wrote: I wish I knew more about the Naza stuff, but it's closed source and proprietary and that makes my interest level close to zero.

Hahaha no CLI commands, what ya see in the GUI is what ya get

(27-Sep-2017, 08:40 PM)RENOV8R Wrote: Hahaha no CLI commands, what ya see in the GUI is what ya get

Right, but I want to know how it works and when things don't do what I expect, I want to look at the source code to understand why.

It might be a computer programmer's affliction, but as much as I can, I want to be able to understand, tinker with and modify my flight controller and its firmware.

I've never been a fan of black boxes that you are not allowed to open or investigate.

   
Howdy Boys,

This note is just to recap some of my earlier posts for those who have joined recently and are wondering what on earth "Wooden It" is?

Wooden It is a quadrotor test bed designed purely to test the performance of various flight controllers and the lifting power of the motors with various prop combinations.

In its real life role as part of a transitional fixed wing aircraft Wooden It (or at least the four motors) will be required to lift 5.6kg to a height of 20 meters and lower 5.6kg safely to the ground from a height of 20 meters, all while operating on 12V (3S LiHV batteries.) and fitted with 13 x 4.7" SF props. That is it. No horizontal flight, no flips or racing through hoops. It is just simply an elevator.

When I began this project I knew absolutely nothing about quad rotors and six months or more on, I still know almost nothing about quadrotors.

The first FC I purchased in complete ignorance was a HK V3 configured to "+" which was not the correct layout. Wooden It is a slightly rectangular motor layout and the plus sign layout was not up to the job of controlling such a layout.

The next FC was a Hero 32 which I found provided good stability but could not deliver the total thust required on 12V.

The third FC was a DJI Naza M which has proven to be quite satisfactory in all respects providing good stability combined with producing 7.6KG total thrust in manual mode. The only query on the Naza M is a rather odd non-linear throttle response in Atti Mode. I have yet to run the final thrust tests in Atti Mode. 

In spite of the strong wind during my last farm stay I have managed to get the fine tuning of the Naza M in Atti mode to the point where I am now starting to explore climbing to 30 or 40 meters and descending from 40 meters. The descent being a particular worry in as much as I am uncertain just how much thrust is required to slow a rapid descent. So far in slow descents there appears to be ample thrust.

Thus as you can see all is going well and if ever I have the good fortune to have another calm day I should be able to complete the fine tuning, thrust and rapid descent tests.  


Oh for that day!

KK

Just 2 thoughts (i'm sure you're aware of anyway)
- atti mode keeps the quad level. If wind is somewhat constant, acro mode might be easier to keep the quad in place
- fast straight descents are always difficult because of falling into propwash

(30-Sep-2017, 06:38 PM)fftunes Wrote: Just 2 thoughts (i'm sure you're aware of anyway)
- atti mode keeps the quad level. If wind is somewhat constant, acro mode might be easier to keep the quad in place
- fast straight descents are always difficult because of falling into propwash

Thanks FF. I am aware of the falling into prop wash scenario but I am not sure that the Naza M has an acro mode.

I don't think I have ever seen a reference to Acro in the manual. I will check again today.

I am also hoping to do some heavy lift testing in Atti mode today as well.


Stay tuned.    

KK

   
OK Lads,

Just finished the heavy lifting tests and got the best result so far and in Atti mode.

8.2kg using 12V, combined with 2 off 12 x 6 APC SF CCW props and 2 off 13 x 4.7SF CW props.

I would have used 4 off APC 12 x 6 SF if availble but the 12 x 6 SF CW props are just not available. Or so I believe.

Does anybody know of a source of 12 x 6 SF props in CW/CCW pairs?

Old Wooden It was very lively with that prop set but the peak current with the 12 x 6SF was 44.1A as against 40.6A with the 13 x 4.7SF so perhaps the 13 x 4.7SF may be best after all.

The strange throttle response is still evident but it certainly did not result in an overall loss of power, quite the contrary. If you look at the graphs you can see the dip in throttle and revs at about the mid throttle point as I advance the throttle. That is not me doing that it is the FC.

So there you have it. Another step forward.

Back to the farm tonight so stay tuned. Do not leave your computers.   

KK

Oh by acro i just mean non-atti mode... think it's called manual mode for the naza.

Let's say you have constant wind from the left side, in atti mode you would have to constantly hold the stick to the left in order to stay in one place.

Regarding the throttle dips at midstick - doesn't the naza come with a barometer? Afaik the naza atti mode should try to hold height at throttle mid, so if it has a baro maybe you need to calibrate it?