CarbonCore Cortex....Owners' Thread

[Superbowser]

Hi Paul,
Good Job ! superperb.

To all of our customers who liked to get a Cortex RTF with A2, we still recommend to use the WKM. We didn't find out the advantage of the A2…only new bugs ( the retract twitch is maybe not a bug sorry, maybe its marketing ) and wow ..a new big range for gain setting up to 500%. Good to know that the GPS Pro of the A2 is much more precise… .The MacOsx Software is still sending other gain settings to the FC as its shown in software. unbelievable to see that the customers are still beta tester for the products of this company, cause they paid so less money for their A2 FC….or ?

 

[Mrtarango32]

View attachment 17382
It's coming together.

 

[sk8brd]

gain range up to 500% is not out of the ordinary. people on large custom setups with greater then 20 inch props have had success with gains in the 400% range doesn't mean you have to use them. tune your craft to the gains that work---obviously.

i got a feeling thats why they bumped them up maybe something bigger then the s1000 planned. since they just released info on the ronin today wouldn't be surprised. the s1000 cant handle an epic as easily compared to the bigger custom rigs. dji is dji we all know at this point what were getting into when we buy their products.

Quinton- i would just experiment. the bigger props on the bottom probably give you efficiency back thats why its recomended, if its stable, motors are not hot or esc's your good!

there are several people with smooth a2 setups on s800's and s1000's. don't know of many on co axial setups w/ the a2. if the craft is not flying smoothly gains first if not then same size props all around and see. i don't really get how one set of gains can work with different sized props. if i go one size up on non coaxial crafts changes. gains should really be setup to be adjustable every time you fly. what works one day won't the next if conditions are different due to wind etc. pretty easy to do with btu unit.

 

[Quinton]

Getting tired of this now, not having much luck.
Last week I got everything all up and going OK, and checked it out on the Assistant, everything seemed to be good, so I screwed the lid on with all new screws.

Today wanted to try a test flight, so I plugged it back into the assistant for 1 final check after reading about the 500% gain and tried a motor test.
All motors worked fine except m1 which was twitching.

Not a good sign, so went to take the lid off again, this time I could not get 3 screws out (I am using brand new allen keys before anyone asks) and just loctite blue 248 for the screws.

Spent the next hour getting the screws out, I did try the soldering iron trick to heat them up a bit but no help.
Only way to get them out seems to be to get a dremmel and cut a notch in them for a screwdriver.

Tried doing a csc a couple of times and all motors worked fine except for m1 which still twitched.
Should have learned last time if you got a twitchy motor dont push it, pop the ESC blew...

Ok that makes me think is there anything wrong with the actual motor, so hooked it up to a spare hobbywing ESC and a servo tester and there seems to be no problems at all with the motor.
I really am at a loss not to mentioned a bit p*ssed off as it really should not be this hard.

I dont mind changing an ESC, but it is a right PITA trying to get a new one soldered on again each time, the holes in the PDB are really small.
Do I just buy a new PDB and start from scratch with new ESCs that I bought weeks ago.
I am losing the will on this one.

Yes it is the same motor (ESC) that went last time, but surely if there was a problem with the motor it would not work on the servo tester and hobbywing ESC?

 

[sk8brd]

check for a short. if the motor works with the other esc then most likely not the motor. imo- something in that area is shorting them out like that last time. check all motor wires/esc wires are insulated from anything conductive like the frame and screws.

 

[Mrtarango32]

View attachment 17391
Almost all together.

Set up the wkm and zen today.
Have the frame pretty much buttoned up.
Does anyone else think the lg and cortex seems to flex a lot with a ton of weight under it?

 

[SwarfWorks]

Hi Paul,
Good Job ! superperb.
...unbelievable to see that the customers are still beta tester for the products of this company, cause they paid so less money for their A2 FC….or ?

Yeah, I have heard that so many times with DJI products. And I agree. I feel like my ~$12k I've spent on DJI equipment should get me on their payroll as a R&D engineer.

View attachment 21477
Does anyone else think the lg and cortex seems to flex a lot with a ton of weight under it?

Yup. I totally agree. I bet it would feel good with the standard length legs, but with the longer ones for the Zenmuse, it actually makes me a bit nervous. Definitely more "wiggly" forward/backward than side to side. Your Cortex is looking good btw.

check for a short. if the motor works with the other esc then most likely not the motor. imo- something in that area is shorting them out like that last time. check all motor wires/esc wires are insulated from anything conductive like the frame and screws.

Maybe a long shot, and I'm sure you'd have noticed, but I found a couple bullet connectors on the motor leads that were quite loose. I used a razor blade knife to "open" them up a bit to make them fit tighter. Doubt it's your problem, but wouldn't hurt to pay attention to. As you may know, 3-phase motor will turn with just 2 leads connected, but not very nicely.

Ok that makes me think is there anything wrong with the actual motor, so hooked it up to a spare hobbywing ESC and a servo tester and there seems to be no problems at all with the motor.
I really am at a loss not to mentioned a bit p*ssed off as it really should not be this hard.

I dont mind changing an ESC, but it is a right PITA trying to get a new one soldered on again each time, the holes in the PDB are really small.
Do I just buy a new PDB and start from scratch with new ESCs that I bought weeks ago.
I am losing the will on this one.

Yes it is the same motor (ESC) that went last time, but surely if there was a problem with the motor it would not work on the servo tester and hobbywing ESC?

After my unintentional meeting with the wall (again, my fault), I thought I ruined several of the motors, as they would kinda sorta spin doing the "motor test" function. So I ordered replacement motors along with the esc's. Yeah, didn't need a single motor, just six esc's. Like I've read other places, brushless motors these days are quite strong and the esc's are typically the weak link and pop like a fuse.

If you have a multi-meter (ohm meter at least), check for continuity between each motor wire and the frame (ground) of the motor. If you have continuity, then you probably have a shorted motor. Also, when you have the motor leads unplugged from the esc to do this, hold the bullet connectors of the motor together (alternate 2 together and then all 3 at once) and the motor should be physically harder to turn when the leads are touching each other.

Hope that helps. I'm not the expert on that, but that's just a few things that I've learned.

 

[sk8brd]

there could also be a screw in the motor thats protruding too far into the housing. I've heared of this before before on brand new motors which causes shorts on esc's. good point Swarfworks about testing the motor for continuity.

 

[Mrtarango32]

View attachment 17445
Almost there.
Weights just at 10lbs (USA USA USA)
Almost all buttoned up.
Need to find out how id like my fpv gear set up. Other then that. Get a Bluetooth led, iosd mk2 and I'll be all set.

 

[Quinton]

View attachment 21535
Almost there.
Weights just at 10lbs (USA USA USA)
Almost all buttoned up.
Need to find out how id like my fpv gear set up. Other then that. Get a Bluetooth led, iosd mk2 and I'll be all set.

Looking good, that 10 lbs (4.5kgs) is that without camera/gimbal, also how are you going to do the motor setup, all CCW top and CW bottom, or the other way?

 

[Mrtarango32]

That is with the camera/gimbal.
Pretty much everything. But props, fpv gear and lipos.

Running it like this View attachment 17453

 

[deluge2]

I learned the hard way years ago when assembling high-end RC buggies and trucks with literally hundreds of hex screws, *never* use 'allen keys', brand new or otherwise. I think you will be much happier if you invest in high-quality hex drivers that use replaceable tips made of hardened steel drill rod that have been ground to form the exact proper hex size. These are a very tight (ie, precision) fit in the screw socket and greatly reduce the chance of 'rouding out' the hex recess, particularly when removing thread-locked screws, or when driving hex screws into composite holes that are not pre-threaded. These don't guarantee success on every occasion, but they do greatly reduce the frequency of problems.

Because they're made from hardened steel, they will not wear out quickly even with frequent use. You probably will only need a small number of driver sizes to handle all the hex screws you're likely to encounter.

Once you've used these drivers, you'll never want to use mass-market allen keys or hex drivers again for anything critical.

Steve

<snip>

Not a good sign, so went to take the lid off again, this time I could not get 3 screws out (I am using brand new allen keys before anyone asks) and just loctite blue 248 for the screws.

Spent the next hour getting the screws out, I did try the soldering iron trick to heat them up a bit but no help.
Only way to get them out seems to be to get a dremmel and cut a notch in them for a screwdriver.

<snip>

 

[R_Lefebvre]

Agreed on the quality hex drivers. Problem is... where to get them? I bought a set darn near... wow 15 year ago? Integy brand name. They were like $100 or something for the set. But they have lasted 15 years. They are getting worn though. I've tried to replace them, but everything I've bought has been junk. Would be nice if tool manufacturers published data on the tools such as rockwell hardness and charpy impact, but... I can dream...

 

[Quinton]

Agreed on the quality hex drivers. Problem is... where to get them? I bought a set darn near... wow 15 year ago? Integy brand name. They were like $100 or something for the set. But they have lasted 15 years. They are getting worn though. I've tried to replace them, but everything I've bought has been junk. Would be nice if tool manufacturers published data on the tools such as rockwell hardness and charpy impact, but... I can dream...

This might help that was mentioned from Jes at the start of this thread..

Good luck getting that out! I'm afraid I don't have any suggestions. But when you succeed, I can suggest replacing them with quality Torx (TX) headed screws (stainless steel, of course). The shape of the head/bit is MUCH better for small sizes - they don't get chewed out like hex heads do.

Screws here:
http://www.pts-uk.com/Products/Socket_Screws (Cap, button, flanged button and low head types)
Tools here:
http://airbugz.com/pro-tools/32-wiha-picofinish-torx-screwdrivers.html (shameless self-promotion - my own site )

 

[sk8brd]

i use huddy hex drivers never had a problem and have replaceable tips. never stripped another dji hex screw on any of the builds i was part of after those. there were pricey but better then drilling out screws then having tiny fragments enter into the motor.

 

[SwarfWorks]

That is with the camera/gimbal.
Pretty much everything. But props, fpv gear and lipos.

Running it like this View attachment 21543

I'm very tempted to try this as well. My Cortex seems to yaw alright, my problem is that when I do a slow pirouette (~10-20 seconds per full 360 degree), instead of spinning around it's center, it makes about a 20-30 foot circle. I do have my measurements correct on my IMU and GPS puck placements.

 

[Soggybear]

Hi Everybody,

I just thought I would introduce myself. I purchased an ARTF Cortex about 6 weeks ago but finishing it and getting it up in the air has been hampered by a couple of technical issues, delays from suppliers (DJI) and general personal stuff getting in the way.

My Spec is:

Standard Cortex with extended landing gear for Zenmuse
DJI A2 Flight controller
iOSD
Zenmuse gimbal with Panasonic GH3 camera
Futaba 14SG Tx
2 x 5000 mAh LiPos
Flying weight so far is 6.775 kg

I have been part of the whole landing gear 'twitch' saga. I have not tried Paul's solution in post 191 yet. In the meantime I have just added a switch to the signal wire. I turn it off when I connect the battery and then switch it on. Great until I forget to turn it back on before taking off! I agree with Paul that it is not simply a case of reversing direction using the TX or FC as it always ends up opposite to the direction which is needed.

I am curious what people are actually using for their gain settings with the A2. Obviously it will change from unit to unit but a solid set of initial 'Basic gains' and 'Attitude gains' would be very helpful.

Initially I am setting up as a single TX to control the Cortex and Zenmuse. I am also curious how others are mapping the Zenmuse channels given only 3 spare ports on the A2 (F1 being used for landing gear).

Anyway, I agree with previous posts which stated that Cortex is a clever design. I love how compact it can get. I also agree that a method of quickly releasing the legs would be a huge advantage. I considered the Peli 1770 case on the CC FB page but I am not interested in taking off the gimbal every time I put it into a box.

Anyway, I look forward to sharing my experiences. I will post some photos of my build soon.

Jeremy

 

[Quinton]

Hi Jeremy

Unfortunately I have had a few problems, but hopefully I should be back up and running again soon.
However when I did my last flight I took a screenshot of the gains with a 2.5kg weight hanging underneath and 2x 6200 mAh lipos, now it still needed much more tweaking (I needed to go up quite a bit on my Attitude but never got another chance)

I was at
Pitch 214
Roll 214
Yaw 120
Attitude Pitch 166
Attitude Roll 166
Vertical 207

Like I said I only had 1 quick flight with these settings at that weight, before I was grounded, but it still needed a good bit of tuning.
This was with the A2 and latest firmware.
You can do your tests with all the default settings and no weight, it was safe enough.

Look forward to get it back up in the air soon to do more testing.

 

[jay.en]

Hi Jeremy, I'm new here too and don't usually post, though you have the exact same setup as me, except my FC and gimbal is still on back order

Anyway, I thought I'd introduce myself, as I would love to know what gains you end up on and how much time you get with the 5a/h batts. I have 4 x 3s, 5200mah which I will wire in series (2x2) to use at first, but will see if I can get some higher capacity batts whilst keeping the uav at or under 7kg.

Also, with the retracts, why aren't you utilizing the receiver for the 14sg? In mode D, you can get 6 channels straight from the rx, plus 8 ch via sbus into the FC.
I understand you won't get the DJI failsafe retract option, but do you really want that?! You can set a failsafe into the 14sg itself, so if you were to lose radio contact with the UAV the legs would automatically come down. You can also set servo speed, reverse, etc..... Just a thought.... maybe I have missed something..

anyway, all the best! Jason

 

[sk8brd]

i believe there using internal rx on the a2.