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OldGeek
05-04-2011, 06:01 AM
http://www.youtube.com/watch?v=HPfYDv0o31c


Trying different home-made frames out and I'm a horrible pilot!

Cheers,

-don

KirAsh4
05-04-2011, 06:35 AM
Nice flight, looks pretty stable except for the occasional oscillations, but as you said, you need to do some minor tuning still. In your video description, you say you're powering the motors separate from the Mega & Shield. What made you do that? I think the consensus here is that you ought to power everything from the same power pack ...

goodwind
05-04-2011, 06:41 AM
nice frame! How well the foam absorbs shocks? Deforms at impact?

btw i`m powering arduino separate too - don`t know why, just "i want it that waayy" :D

OldGeek
05-04-2011, 06:48 AM
Nice flight, looks pretty stable except for the occasional oscillations, but as you said, you need to do some minor tuning still. In your video description, you say you're powering the motors separate from the Mega & Shield. What made you do that? I think the consensus here is that you ought to power everything from the same power pack ...

Thanks, I did it following the recommendation on the wiki; keeps the Arduino running cooler...

http://aeroquad.com/showwiki.php?title=Hardware+Assembly+-+Power+Distribution

Arduino power source
Although using the main battery for providing power to the Arduino is fine, it is recommended to use a separate battery, such as a small capacity 7.4v Lipo, to do so. This will ensure a clean power source for the Arduino and also reduce the heat generated by its onboard voltage regulator. A good such battery is the Rhino 610mAh or 460mAh 7.4v Lipo from HobbyKing, each costing around $4.

lokling
05-04-2011, 06:50 AM
Nice, how is it affected by wind - and what type of foam did you use?

OldGeek
05-04-2011, 06:54 AM
nice frame! How well the foam absorbs shocks? Deforms at impact?

btw i`m powering arduino separate too - don`t know why, just "i want it that waayy" :D

Thanks, I threw it together in two days just to see how the 2" ducts around the props would increase thrust.
While I haven't had time to measure the differences I can hover with a little over 1/3 stick and this thing weighs 200g more than my first version quad which required just under 1/2 stick (everything else the same).
The foam is quite durable and doesn't dent readily. The deformities you see are imperfections in my manufacturing failures. I used a train transformer, a couple 3/8" pine rods and copper wire to cut the foam.

OldGeek
05-04-2011, 07:07 AM
Nice, how is it affected by wind - and what type of foam did you use?

Honestly I was so focused on keeping the quad above ground, outta trees and away from people, I didn't notice if there was any wind!
The quad certainly seems stable (until I actually use the transmitter :) Don't know if its obvious from the video but this is the 2nd
thing I've flown, first being another quad I made two weeks ago. So this entire flights goal was to keep the quad in the road; of which I failed ~ 50% of the time :)

Here's a link to the foam, 2" available at home depot.
http://insulation.owenscorning.com/homeowners/insulation-products/foamular-150.aspx

propellerhead
05-04-2011, 07:13 AM
Kudos for the novel concept. Boy is that thing LOUD. Did the foam make it lounder or is it just the motors? Not being a flying rotating knife is a big big upside :)

OldGeek
05-04-2011, 07:27 AM
Kudos for the novel concept. Boy is that thing LOUD. Did the foam make it lounder or is it just the motors? Not being a flying rotating knife is a big big upside :)

The motors are loud I went with cheapies, once I decide on a frame/weight and such I'll be begging folks here for a good recommendation.
http://www.hobbypartz.com/alpha-370--1080kv--brushless-motor.html

Here's the same motors in action w/o the foam, quieter? Maybe?
http://www.youtube.com/watch?v=e2Pk8KkmaAw&NR=1

The blades as far as I can tell are perfectly balanced, two sets of using APC 10x4.7.
I think I might be able to get the motors a tad quieter with balancing...
I saw a video somewhere when I get the chance I'll be doing that.

Darkwolf
05-04-2011, 08:20 AM
Regarding keeping the Arduino's power reg cooler by using a lower voltage Lipo; Wouldn't it be more efficient just running a couple of 1N4001 power diodes in series? Each power diode in the series will attract a 0.7 volt power drop, and the total current going through the Arduino is well below the specs of the diode. Put 4 in series and you have a 2.8 volt drop, bringing your 11.1v LiPo down to 8.2v, which should be easy for the onboard regulator to handle.

You'll also save a lot of weight, and only have to handle one LiPo. Thoughts?

goodwind
05-04-2011, 09:52 AM
You'll also save a lot of weight

Rhino 610
Weight : 35g

Sazabi
05-04-2011, 10:10 AM
Darkwolf, 78LM05 will do job much better, providing 5V and around 1.5Amps. It capable to handle up to around 20V and has only 3 legs.
Anyway, my quad fuel batts are 11.1V and for electronics I use separate 7.4V 730mAh Lipo. Imho it feels safer for electronics powering quad this way. And still it's much "I want it that way", as goodwind sad.

jaguar
05-04-2011, 12:09 PM
I love the look of that.

How far from the tips of the blades is the edge of the foam? And did you add any reinforcement to it?

KirAsh4
05-04-2011, 02:01 PM
I can certainly understand the "I just want it that way." aspect of it all. Nothing wrong there. I'm just thinking of what could possibly go wrong. If for some reason your Mega/Shield loses power, will your motors continue working since they are powered separately? Will it become a run away quad at that point?

goodwind
05-04-2011, 02:50 PM
I can certainly understand the "I just want it that way." aspect of it all. Nothing wrong there. I'm just thinking of what could possibly go wrong. If for some reason your Mega/Shield loses power, will your motors continue working since they are powered separately? Will it become a run away quad at that point?
nope. Arduino telling to the ESC how much thrust quad needs. If you disable arduino power, quad will fall down

piratedninja
05-04-2011, 03:31 PM
I did something similar using those foam posterboards you can buy at just about any place that sells posterboard.
It does an extremely good job at keeping the quad flying smooth.

In my tests i was using the same PID values with and without the posterboard attached and when i tried to fly it without the board, the quad was totally unflyable. however once i put the board on, it flew better than it has ever flown before.

Your design is much better than what i came up with, and it looks like its working very well.
Try flying with the same PID values but with the foam removed.

not sure how efficient it is though

OldGeek
05-05-2011, 12:23 AM
I can certainly understand the "I just want it that way." aspect of it all. Nothing wrong there. I'm just thinking of what could possibly go wrong. If for some reason your Mega/Shield loses power, will your motors continue working since they are powered separately? Will it become a run away quad at that point?

Good question, I'll defer to goodwind on that one.
I do know that if I forget to extend my JR-XF622 radio antenna and the quad is 30' from me it goes insane :>

Bottom line I chose the extra battery for three reasons..
1.) Concern over noise from the ESC/Motors on the same line as the Mega
2.) The Wiki actually states using a 2nd battery running at 7.4 instead of 11.1 kept the mega running cooler.
3.) Its a mere 46g of my total 1616g :>

-don

jaguar
05-05-2011, 12:57 AM
Awesome, someone else is using a XF622 as well! Gotta be careful with that guy, I hit the antenna on the tx with my props the other day and took a good chunk out of two of them.

OldGeek
05-05-2011, 12:59 AM
I love the look of that.

How far from the tips of the blades is the edge of the foam? And did you add any reinforcement to it?

Thanks a lot!

The clearance from tips of blades to inside of the circle is 0.5in, no good reason other than I hate fractions. The props are APC 10x4.7, a set of normal and pushers, so total diameter of the circles are 11inches, a nice round number :)

OldGeek
05-05-2011, 01:07 AM
I did something similar using those foam posterboards you can buy at just about any place that sells posterboard.
It does an extremely good job at keeping the quad flying smooth.

In my tests i was using the same PID values with and without the posterboard attached and when i tried to fly it without the board, the quad was totally unflyable. however once i put the board on, it flew better than it has ever flown before.

Your design is much better than what i came up with, and it looks like its working very well.
Try flying with the same PID values but with the foam removed.

not sure how efficient it is though

I must confess both flights Ive done with this quad was with -0- PID tuning and with stable mode ON :> I was too anxious to see it launch and the configurator on my dell laptop is too querky!

Overall the important question I found was how far should the blades be above / below the quad top surface? The prop tips are now dead inline with the top of the quad allowing just the cutting edges to peek above. I found that if you drop the props cutting edge down inside the circle the quad is absolutely uncontrollable.

Not sure why as I thought the simple reaction torque of the rotors was cancelled by running two props clockwise and the other two counterclockwise. But field tests reveal otherwise.

In this config (default configurator values) the thing handles very nicely. The only instability I've experienced is my transmitter, err scratch that's actually my piloting :) Just flew it minutes ago today in Raleigh where its gusty dreary day and it was absolutely stable.

I plan to do PID tuning this weekend and take it to a local field to let it rip, if it happens I have the wife snap some video.

OldGeek
05-05-2011, 01:24 AM
Awesome, someone else is using a XF622 as well! Gotta be careful with that guy, I hit the antenna on the tx with my props the other day and took a good chunk out of two of them.

Yeah I love this radio, just replaced the old Nicad battery with a Nimh as the nicad would last literally 5 minutes! Bought the radio and a Lite Machines 100+ helicopter as a kit I put together 10 years ago which I never did master flying, for that matter never had it off the ground for more than 5 minutes. Mainly I think because I could never keep the gas motor running smooth. I became so disappointed I shelved both of them. Now after playing with these motors I am thinking its time to retrofit the lite machine with a 400+ size and maybe even a mini shield :)

Oh to answer your question which I missed about reinforcement on the foam.
I have two 3/8" square 24" long plywood rods countersunk into the foam and epoxied to hold the motors, that's all it needed.
No reinforcement inside the circles, or on the bottom.

I did later add two more of these 3/8" rods as landing skids to keep the motor bolts from scraping the asphalt :>