1st Electrohub build confusion

[wmmc01@gmail.com]

Thanks for the clarifications NHS77. I'll make the adjustments, change the battery, add some weight and see what happens. May not get to test until Friday, but I'll let you know the results. Thanks again for all the guidance, and you are now peaking my interest with the motor and battery calcs by making them relevant.

BTW - Love Switzerland! Took a family vacation driving from Geneva to Montreux to Zermatt (actually was it Tasch? then by train to Zermatt). Up and down the Matterhorn. Then took the car train through a tunnel in the mountains to drive to southern Germany. Awesome trip. Also been to Zurich and Bern several time for business.

 

[NHS77]

cool

good luck with the next test, let me know, take some video if you can.

the whole battery-weight-thrust ratio is a core aspect. I have bought some 1800kv motors a while ago and I yet have to figure out where the sweet spot in terms of weight / 3S/4S / prop size is for these...

 

[wmmc01@gmail.com]

Arrrgh! Other than the adjustments in MWC you suggested in terms of Mid and Expo for Throttle, I added 200 grams of AA batteries (one on each arm up against the electrohub, and 4 on a pack taped to the tray) and tried again, and again, and again! It seems to take off more slowly, but as you can see it quickly shoots off the the right of the frame and rapidly gains altitude. You can see I try in the beginning of the vid to bring it back towards me, but then it goes off. It climbs so fast and away from me that when I attempt to bring it back it is going into the trees, and to keep from loosing it I just cut the throttle.

I don't understand the numerous Electrohub Flip 1.5 videos that they just take it out and it immediately goes into a nice hover, and then they play with gently controlling the quad, and it responds and behaves? Sorry for the rant, but I just don't get the ready-to-fly aspect. I am only using the standard kit from FT, and the standard power pack from RTFQ. Although after my first out of control experience I changed the Lemon Rx to the Spektrum AR610. Pretty frustrated. Should I flash the FC with the Spider config file available in the RTFQ Dropbox, even tho that is how I ordered it.

My third attempt it tried to trim a tree and came down hard. Bent and broke the tray. Lost a couple of legs. Good thing I already ordered more legs as well as that new tray you pointed out.
Help me . . .

 

[NHS77]

Ouch! That drop out of the sky is harsh...

To be honest I don't get those guys with the flip 1.5 hovering perfectly out of the box either. My first build was pretty much exactly the same as yours and I had all sorts of problems. I also did many things wrong and learned a lot but the FC itself never really gave me a good flight experience. I upgraded to a Flip 32 (Naze clone) and things got much much better onwards. Strangely enough, on later build I was short an FC and slapped the old Flip 1.5 on there and it did pretty well. But this was a standard quad not a spider and I had erased the EEPROM (through Ardiono) on the chip and reflashed it with fresh firmware. So this is something you could try as well.

The FT Spider Sketch from RTFQ to my knowledge is exactly the same as the standard quad. What would be relevant is the motor mix I mentioned before, which is asymmetric on a spider. This is something that can easily be modified in Cleanflight (for boards like the Naze, CC3D, etc.) and should be possible in MWC although I have no idea how. This helped my Ehub fly a lot smoother... but it's something down the road when your ship basically flies ok.

I would suggest at this point you get yourself another board like cc3d (20 bucks) as you can run cleanflight on it or the Open Pilot software. The later has a great setup wizard and with that I have had those out of the box perfect hover experiences. Or when using cleanflight you have a ton of options, which are easy to access (and lots of tutorials on it) to combat all sorts of strange behaviour. It's a fork of MWC, but you don't need to mess with the arduino code to change things. This of course is assuming that you don't have any hardware / build related issues on your ship.

Lastly, why your quad drifts to the right, apart from the FC possibly just not working well, could only be a matter CG, ESC not calibrated properly (although that should result in worse behaviour) or some sort of RC input it receives which shouldn't be there. Perhaps see if you can use the trims on the radio to get rid of it for now.

Also, looking at the video: It doesn't do all that bad in the beginning, then you let it rise. Starting out it is difficult piloting these things. I believe with some practice you can get this thing to hover as it is. Many constant and small inputs instead of big gestures...

Sorry I can't offer more specific help at this point...

 

[wmmc01@gmail.com]

If you thought that drop was hard, you should have seen the next attempt after it was done trimming a tree!

Actually you have been giving great guidance and this last post has given me food for thought. Also, I appreciate you periodically reminding me that I am a beginner, at best. Which drives me to practice more with my nano.

The good news is that my new legs and the new 11.75" tray arrived from FT yesterday. That tray is quite nice and hefty. Hope I can figure out how to assemble it!

So, based on your feedback, here is my plan:
- I am going to reflash the Flip 1.5. Can't hurt and it's something under my control.
- I bought spare wooden booms right up front, so I could reconfig this as a straight quad. I'll have to think about this, tho and will likely try the next item first.
- I did some reading online and like what I see regarding the CC3D and Open Pilot, so I ordered one from AMain in Calif. (I'm in eastern USA). The Open Pilot Store was out of stock. Anything else other than the SW I need from this: http://www.amain.com/rc-drones/copt...controller-w-case-cables-cc3depb-cc3d/p443832

Does Open Pilot allow you to adjust what is needed for the Spider config/motor mix?

Would a tri be any better or worse? When I first bought the FT kit I was choosing between the Spider and the Tri, got the spider because it seemed more straight forward!

Very Best Regards! Bill

 

[NHS77]

The FT Rail system is pretty cool, just got one as well, makes balancing a breeze.

Congrats on the CC3D! Just download the GCS software from Open Pilot but make sure to NOT get the latest release but the one before as it does not support the CC3D at this point. Run the Setup Wizard which will take you through EVERYTHING needed to get you in the air. At some point in Config you will be able to choose from a variety of presets based on popular frames. Choose the QAV400 preset which will be closest to the Ehub.

This video tutorial series is a fantastic guide: http://www.youtube.com/playlist?list=PLYsWjANuAm4r-E61stLchCR4bzY3NmDNh

I have not tried to do a custom motor mix in Open Pilot but I'd be surprised if you couldn't do it. Do some research in the Open Pilot Wiki. This article explains the concept and how it's done in Cleanflight: http://blog.oscarliang.net/custom-motor-output-mix-quadcopter/ And remember this something for fine tuning.

I used this as a guide on my Spider quad with great success. And mind you, you can also run cleanflight on your CC3D - you have options now

Looking forward to hearing back from you!

 

[NHS77]

Forgot to respond regarding the Tricopter: I just finished my first one. The V3 from RCExplorer. It is a dream. Love it. Had some hiccups in setting it up though. Also I think a quad is more straight forward to build and easier to learn on. Also I believe you'll only appreciate the way a Tri performs if you're familiar with quads. It's similar to control but it feels much more like a bird in the air than a machine.

I doubt I would have been able to pull off this build as my first. So get your spider in the air, fly it for a while and experiment. Then build another one, perhaps a 250 and the get a Tri...

 

[wmmc01@gmail.com]

Good - glad I got the spider first then. The V3 looks pretty cool. Are you using the servo for the tail?
Also, thanks for all the links and I just downloaded the correct version of Open Pilot so I have it and thanks for the Play list links and the one for OscarLiang - who I have valued for other guidance things he writes up!

So is Open Pilot no longer supporting the CC3D? Just curious. Glad there is the option of Cleanflight.

I'll let you know the next outcomes.
Thanks, Bill

 

[wmmc01@gmail.com]

OK, I'm Back!
CC3D installed and programmed. Used the Wizard and guidance from Painless 360 videos (https://www.youtube.com/channel/UCp1vASX-fg959vRc1xowqpw) Had an issue originally with the bootloader but followed the Open Pilot Rescue and it all worked out.

All out weight is 1.2 kg. Using the new tray from FT.

MUCH better control and performance! Thrilled with this! This is the "out-of-the-box" maiden experience I expected all along. Thanks NHS77 for the recommendation.

See this video of attempt 6 of maiden flight:

Two issues: 1.) Pitch is reversed which I am sure I checked but at one of the Wizard checkpoints is was backwards again so I unchecked it. Easy fix.

2.) As you can see, it's doing a lot of hopping, which I am sure is at least partly me, but is there an adjustment I can make in Open Pilot to make the Throttle less sensitive, or is it something else I should be examining???

Thanks in advanced! Bill

 

[Billchuck]

2.) As you can see, it's doing a lot of hopping, which I am sure is at least partly me, but is there an adjustment I can make in Open Pilot to make the Throttle less sensitive, or is it something else I should be examining???

Thanks in advanced! Bill

The pogoing is due to the effects of ground effect, inertia, and the timing of your throttle control.

Close to the ground, air through the props creates a cushion under the quad, giving you more lift for the same thrust. The quad shoots up into the air. You back off the throttle as it shoots up, but inertia carries it higher, so you back off more. It doesn't have enough lift to stay up there, so it falls. You put on throttle but inertia keeps it falling, so toy throttle up more. It falls into ground effect, giving it more lift, so it shoots back up. The height of the effect depends on the size of the quad and the thrust generated. Your nano has the same problem, but it's so small that you only will notice it within a few inches of the ground.

Dealing with it takes practice and learning where the ground effect starts to affect the flight characteristics. Adjusting the throttle curves as described previously will give you more fine control where you need it.

Try for a smooth hover 10-15' off the ground, rather than a couple feet. It will be much easier there than down low where a few inches of height has a noticeable effect.

 

[wmmc01@gmail.com]

Try for a smooth hover 10-15' off the ground, rather than a couple feet. It will be much easier there than down low where a few inches of height has a noticeable effect.

OK, Thanks Billchuck, did not realize I needed to get quite that much altitude to get clear of ground effect. Is this why FT is starting to promote Angle Arms?

I also tracked down how to adjust the throttle curve. I'll try both on my next test.
Thanks!

 

[Billchuck]

OK, Thanks Billchuck, did not realize I needed to get quite that much altitude to get clear of ground effect. Is this why FT is starting to promote Angle Arms?

I also tracked down how to adjust the throttle curve. I'll try both on my next test.
Thanks!

I don't know how high you need to be. That height is almost certainly more than enough, so you don't have to worry about it.

 

[NHS77]

Hey! Great to hear that you're having better luck with the CC3D! Confirms once more that the Flip 1.5 despite everybodys thinking is not a great controller at all.

As mentioned before, the hopping is really a matter getting the hang of hovering. Yor stick input basically has to be one step ahead of your quads behaviour. Fly through a couple of batteries just practicing the hover and you'll be fine.

Happy flying!

 

[wmmc01@gmail.com]

Absolutely - and "better" is understated! Now I am confident that the rest is the operator. Thanks for steering me toward the CC3D NHS77.