Tarot 680pro & Naza M v2: will it work?

[Motopreserve]

There were a couple settings on mine that I changed - sorry, you're going to have to do the dance. And worse yet, the program card has the be powered up while doing it. Some special arrangement that really is not worth the effort. I know that a futaba Tx battery does the trick - so maybe you'll be all set if you have 2 radios.

 

[coreyperez]

Scott,

I have a bench top power supply that I use for all my programming / building work. I've been known to leave my MR & Radio (FPV, etc) equipment for hours. Seems I've even ran it long enough while trying to get the damn Multiwii programmed that I ran my Futaba down so low it had to be charged to keep using it. I think it was about 6hours if I remember correctly.

But thanks for the heads up. I may look into it this weekend. I did just realize, we have a 4 day weekend, but i have Staff Duty Officer (duty) on Monday... 24hrs of pure joy. I'll get some studying done at that point.

So, with that in mind, and with any luck, I'll hopefully maiden my Tarot this weekend. I'll have to dig out my notes and see where I left off. I have a problem that I have so many projects going on and in different phases of build I have to leave myself notes to remember where I was. That is how I messed up the ESCs. I planned to check into that and I got distracted by flying Planes and the Naze32 build.

Corey

 

[Motopreserve]

You're all over the place! . Good luck with the test.

The power to be provided is a servo connection - and it's low vomtage, so your bench top might be the ticket... I was a little annoyed by the need to jump through hoops to do some simple programming. Let us know how it goes, and don't forget to turn the radio off when you're done!

 

[Info@key-photos.co.uk]

Has anyone considered slinging the flight controller (MC) underneath the bottom plate of the airframe - same plate the landing legs attached to? The only thing I can think of now to rid myself of these dangerous auto take offs is that the c of g is much below that of the MC in it's current position. Crude measurements indicate cofg being in that under plate location. Anyone?

 

[Motopreserve]

I'm not sure there would be a great place for it - and I think it's been common consensus to have it placed closest to the plane of the prop.

What at is the problem you're having on lift-off? Is it flipping? Are you popping it right to 50% all at once, or trying to slowly get it off the ground?

 

[Info@key-photos.co.uk]

Hi there
There's a video on page 2. Auto take off is positively scarey as you'll see. I had the MC mounted pretty much as you described but the c of g is much lower so I'm considering mounting it(right way up of course) between the payload rails

 

[simondorr]

I know the auto take off is not everybody's favourite function but I have got used to it. just give it the beans to 'pop' it off the ground and then let her settle down at about 4 - 6 feet.

On the continuing saga of my problems I now think it may be a dodgy ESC, take a look at this video discovered today whilst trawling YouTube during lunch: http://youtu.be/bCk63L-xV-0. In the end the finger was pointed at an ESC but he has yet to confirm with a test flight with the new ESC.

I was slightly inaccurate with my report from the bench testing, I did get a beep from something but it was brief and I could not replicate it. I may try again this evening but one motor at a time. I won't be flying before tomorrow now anyway as I am waiting for some smaller hex spacers to arrive, at the moment I have a small tower sitting on the top plate in the form of a very widely spaced power distribution board (top and bottom) and a Tarot top mounted battery plate.

The other thing that bothers me slightly is that it is often difficult to mount the Naza at the CoG and that with different payloads/battery configurations the CoG can change. Not a problem with the Wookong since you can record the distance from the CoG with both the IMU and the GPS puck. However on the Naza you can only configure the mounting of the GPS puck with the CoG, I wonder what the tolerances are for the Naza, it would be interesting and helpful to find out. Just seems a bit of overkill to fit a Wookong to anything but the larger multi-rotors. I certainly wouldn't use it on the F450 but it is marginal for the T680 which is a replacement for the F450 which just cannot carry all the gear I want for use with the GoPro not least the brsuhless gimbal which is way heavier than the servo version I used to have on it and the transmitter for the video feed so that the Director or client can direct/see the shot.

Safe flying guys, I'll be in touch. Out.

 

[Motopreserve]

I have had crashes more like the one in the video you just linked. That seems more like an ESC going bad or losing all control - because it flipped directly over. The issue you had seemed more intermittent (at least initially) - causing the wobble. That's not to say it can't be an esc issue - but different in that his looked like it sh*t the bed completely - and yours at least tried to right itself before the crash.

 

[simondorr]

Hi Ken,

I considered this but the problem with the 680 plates is the size of the holes in the top and bottom plates. They are just a bit too small to have the Naza sitting just proud as the leads from the ESCs, RX and especially the LED and PMU all snag. I actually removed the small spacers and fixed the centre tray to the lower plate in an effort tom give clearance for all the leads. The tray was just a tad too wide to fit between the 2 rails so couldn't lower it any further. I have seen mods whereby the Naza has been fitted to a tray spanning the hole on the top plate and it seemed to fly perfectly well: http://youtu.be/1MGzNbeVgRU

 

[Info@key-photos.co.uk]

the naza is now sitting in a tray between the cargo arms with the Rx upside down velco'd to the underside of the tray. I'll let you know how I get on. . . . .

 

[Info@key-photos.co.uk]

Full battery taking off and landing - it's just the same. Curse you auto-take off. May leave the the FC where it is tho tucked out the way. Nice clean top plate. Space for ioSD later on

 

[coreyperez]

I've got a new "twist" into the possible issue with the flips.

I spent hours this evening.. HOURS, ensuring ALL my motors/props were lined up (when folded together as all the instructions/photos show using a straight edge). It was a long and severely drawn out process. I was just finishing up my props and opted to see how close they were, well one of them caught my attention and I realized after looking, after I unfolded the Hex, one of the arms "twisted", as in the mount is not exactly drilled square. When I put the arms back together (folded) everything is plumb, but when extended one is off-kilter. Photos below.

Top shows the level (different arm) and the bottom photo shows after the suspected issue.

I don't know if it is enough, but I'd believe that with all they hype about making sure everything is level, we wouldn't want "this" to be as far off as it is.

I'm going to make the eyeball adjustment and go from there, I'm hoping to maiden it tomorrow. It has been windy out here in Korea this week.

Corey

 

[johnthorn]

I don't think it makes any difference if the Naza is slightly above the cg mine is in the middle just above the top plate and I have no problems at all. One thing you might want to check is that all your bullet connectors are a very tight fit as if they are slightly loose this will cause flipping, just put a craft knife in the slots and open them up so its really hard to push them in. I recently built a quad for someone and it flew perfectly in my back garden on two test flights, but after he took it home the first flight it took off and did exactly what yours did. On inspection one bullet connector was found to be a fairly loose fit I did the knife trick and it has flown perfectly ever since. This was a fairly common fault with naza flight controllers on this forum about 2 years ago the solution is as I have said, they need checking every couple of months as vibration tends to loosen them, or the more permanent solution is to solder them up. Hope this helps
John

 

[coreyperez]

Well I took the tarot it to the flying field today, it was super windy and I couldn't get the compass to go into calibration... what the heck! Here we go! Flew great, the settings are a little off, if I gave it rapid L/R inputs it would become unsettled, but work it out on it's own in 3 oscillations or so.

All in all I'm happy. I have a 4000 4S under it and the battery gave me about 3:30 total. I was amazed how steady it flew in full manual mode, very responsive and controllable. Even without the compass calibration GPS was rock solid. In hind sight, I thought it was 5-6 flips of the GPS switch, but was 6-10. I'll probably head back out tonight to get a little more blade time. I also need to check, I have the problematic flytrex on it and I had already noticed the GPS cable didn't want to stay in even in assembly.

Corey

 

[Info@key-photos.co.uk]

Thanks johnthorn for the bullets ti

p which I will check out (an old F550 is all soldered and never had trouble) but I think my problem has been down to c of g despite me have checked this.
During more tests in auto take off (still I curse you) I noticed the machine swooped forwards not to the side as usual. A slightly heavier battery was in place and I'd not adjusted - previously I would check cog for'd and aft for balance after battery changes neglecting port and stb. I've previously ignored a little diagonal imbalance maybe caused by battery leads. I've now had several normal take offs. But taking coreyperez's info on board I also checked the motors for level. One was a little out but I also found the brass captive 'nut' in the plastic had come out (see pics attached). Not for the first time on another arm - will try writing to Zhang on this and see what if any reply I get. Two of the other arms had motor mounts that I could swivel with (reasonable force) there is now a 3mm x 6mm self tapper through the motor mount and into the carbon tube, lets see you swivel now. . . . Some other pics attached which might offer some more info

 

[simondorr]

Well after several days of not being able to fly because of the weather there was a break this morning so went for a test flight. I have checked absolutely everything suggested in this thread. I have lowered the CoG by moving the power board to sit under the rails below the bottom plate; put the Naza (which is already as close to the COG as possible) on some vibration reducing rubber matting; checked the alignment of the motors; checked the mounting plates and booms for movement; checked all bullet joints splaying the end of those that were loose with a craft knife; and checked the props. I calibrated the compass in the usual manner; powered up the system and allowed it to find >6 satellites. Take off was smooth, there was a slight suggestion that she might still be a little twitchy so I swung her to the left and then the right. The resulting over-corrections that you see are entirely automatic as I had returned the sticks to the center. The only thing I can think of now is either the gains are wrong Basic-Pitch170,Roll170,Yaw150,Vertical140. Attitude-Pitch170, Roll170. To be honest whilst I accept that they may need tweaking I don't believe it to be this. The only other thing is perhaps the motor/prop combo in that perhaps there is too much power but like the gain settings I really cannot see it being this either as many are using a very similar set up. Motors 750KV props 13 x 4.5. ??????? :-(((( http://youtu.be/XnyHBC-9nPk

 

[johnthorn]

I just checked your pics the one thing I can see is wrong you have a 250mw t/x right next door to the receiver you need to get it as far away as possible from it and the naza, this will cause interference. Also look at your connectors going into the r/x they are not all pushed home properly this is another source of problems, hope this helps
John

 

[coreyperez]

Hi Simon,
I have tarot 4006 620kv motors fitted, coupled to the platinum pro 30amp escs fixed under the motors. 12" props. Looking for smooth flight (for video) my gains are low just now 125 125 100 125 and 125 on the atti pitch and roll
Kenn

Simon,

Double check your settings, Info@key-photos is using these settings, (much lower than yours) and he is having luck.

Mine are as follows:
125 / 125 / 120 / 130
140 / 140 /

Also note, mine are still as little "twitchy" as well. I'm going to dial down my Attitude (from 140 to 125) as he has and see where that gets me. Actually, I'm going to use all of his settings and see where that gets me.

As far as your belief the motors have too much power, that is where dialing down the settings are at. Think of it like a race car, sure it has too much power on city streets, so you set a wood block under the throttle, this "limits" the amount of power/thrust the FC will input and the sensitivity.

I experienced too high of a setting when I went to my TBS Disco Pro (From Naza F550) and I almost had an instance of it flipping over as well.

I Firmly, FIRMLY believe the #1 thing you need to do is dial back your settings. I probably won't get to put mine up in the air this evening, but I'll change my settings Saturday (Its friday here in Korea) and report my findings.

Corey

edit: lastly, do you have your X/Y axis correct on the GPS? I don't know how critical this is, I've never noticed a difference, but it is worth a shot. Also, is your declination correct for the compass? (research the "DJI Toilet Bowl Effect"). Just other thoughts. I"m 100% sold on the settings at this point. Having experienced it previously on a Quad of my own.

 

[simondorr]

Thanks Corey, I follow that logic and that will be my next thing to try out...again. But with trepidation, this was what happened at 100% across the board http://youtu.be/SdONrnICMGg there are other videos with a similar story as I slowly increased the gains. It is interesting to not that some (not on this thread) have a theory that my gains should be even higher. I will keep on trying until I get it right but all very frustrating at the moment. Best wishes.

Yes all X/Y/Z correct. I am aware of the Toilet Bowl effect but the GPS puck on both of my other multirotors don't have an offset and the symptons of this I'm sure you'll agree are not consistent with that though I wish they were as it would be very easy to fix.

 

[Info@key-photos.co.uk]

for johnthorn
Thanks for those pointers, weather set fair so more tests this morn. I've been cranking up my gains basic and atti to the levels simondorr is using to try tighten up the flying characteristics. My auto take off is much more settled now but I can hardly believe it was due to the very minor cog imbalance. Checking this carefully before every take off. Anyone sourced a carry case/bag for their 680 yet?