When inspiration hits...

jhitesma

Some guy in the desert
Mentor
So did a little hand test this morning and found that ELE and AIL were reversed somehow. Setup a new profile in my TX and reversed them, then got my wife to grab the mobius and film the first daylight attempt at flight (2nd attempt overall)


The 5030 props are as anemic as I remember. They left me unimpressed with the warp on it's first flight and they left me equally unimpressed here. It flew just fine, felt mostly locked in with a guestimate at PID's but has a few odd tendencies I need to figure out.

For one it wants to flip all by itself as soon as I go below a hover. No graceful decent just tumbling. Recovers well, but still gotta figure that out. I'm just in horizon right now so it could easily be a poorly setup autolevel pid. Need to get somewhere with more space to see how it does in acro.

Swapped it to some HQ6045's and gave it another try (video still uploading) big improvement, but it still has some odd tendencies like wanting to flip when I let off the power. Need to adjust my TX trims though as my stick commands don't seem to be working so I think my throws aren't going far enough (though I can arm which would tend to imply that's not the issue.) I'm on my gentlest profile right now, would like to try it on one of the more sensitive profiles but since stick commands don't seem to be working....

Overall it seems to be doing pretty well. It looks really nice and stable and mostly responds well. It's not as crisp as the warp for sure, and no where near as punchy - the smaller motors are really apparent at high throttle even on the 6045's.

The 1806 motors are impressive for what they are, but they're no replacement for the 2204's. On a quad that's limited to 5" props the 1806's would make more sense. I could also see them on a hex where their lower thrust is offset by the extra motor and the cost/benefit ratio shifts a bit when buying 6 motors instead of 4 :D But if you've got room to swing the 6" I say go for the bigger motor and swing that 6".

For $150 it's a heck of a nice little quad. But it's definitely NOT in the same class as a warp, I didn't expect it to be but wanted to clear that up in case anyone was holding out hopes :D Think I'm going to hook up my BT module so I can do some tuning, and adjust the endpoints on my TX. I'll like it a lot better if I can get it to stop flopping around like a dead fish when it descends. I'm thinking it may be the big flat plates. I seem to remember Soma saying the cutouts in the warp were more for airflow than weight reduction.

I'd also like to rip it apart tonight and give it a coat of paint, then stick a few LED's on it. Fun build, and a lot cleaner than my knuckle. I still have a few ideas I'd like to try on it. But time is tight since all this gear is going to be moving over to a Twitchity quad soon which should help ditch a few grams and bring back a bit more.
 

jhitesma

Some guy in the desert
Mentor
And here's the quick test with the 6045 props. Not sure why Youtube is only giving the ultra low rez version though:

 

Twitchity

Senior Member
"Transmitter on... beep" that was great :D The 6045 props made a big difference over the 5030's, but I can't see the DYS's being a competitor for the 2204's either. For the price and performance they offer, they are great little motors though.

As for the flipping, it looks to be falling to the same side every time? It's hard to tell from the videos, but that's what it looked like to me. Have you placed the quad on something so it balances directly on the center of the frame to see if one side drops?
 

jhitesma

Some guy in the desert
Mentor
"Transmitter on... beep" that was great :D The 6045 props made a big difference over the 5030's, but I can't see the DYS's being a competitor for the 2204's either. For the price and performance they offer, they are great little motors though.

Yep, they seem like great motors for what they are and the price is really hard to beat. But they're not a 2204 replacement. That said I just strapped a mobius to it and it didn't seem affected by it much either. I think these would be great motors on a 200-230 sized FPV quad for cruising rather than full throttle runs through the playground.

As for the flipping, it looks to be falling to the same side every time? It's hard to tell from the videos, but that's what it looked like to me. Have you placed the quad on something so it balances directly on the center of the frame to see if one side drops?

Haven't investigated too much yet. Want to get the PID's tuned a bit better. And just strapped the mobius to it and flew it around the backyard (even into my daughters playhouse!) did much better for video than I expected. Even with the camera just strapped right to the top of the quad with no padding or anything it looks way better than video from my knuckle. Just a bit twitchy for video same as the warp.
 

jhitesma

Some guy in the desert
Mentor
And here's the tests with the camera strapped to the top of the quad:


These 6045's are definitely too much for these 1806's though. After that video the motors were hitting 110f already and that was just some gentle barely off hover flying.
 

Bluesmike

Member
2:13 - "Not quite the graceful landing..."

Dude that's like ballet compared to my landings. My knuckle quad and BatBone land like bouncing bricks and the flying wing lands by belly flopping!
 

jhitesma

Some guy in the desert
Mentor
Took it out for a bit of flying before sunset tonight along with the warp and it's owner.

Man, that warp. Those KISS ESC's are amazing. It was a great quad before them but now, holy cow. I have GOT to get me a set of those.

Anyway, got a good bit of video and did quite a bit of flying. Went through a couple sets of props and ended up grounding the budget mini when I broke two arms suicide diving into the ground at full throttle. Didn't quite pull out of that one in time. Before that it took at least a dozen hits including a could on pavement in my front yard. It makes this horrible tinkling sound like breaking glass when it hits...but it took a lot of hard hits before it broke. And it broke right where I (and I'm guessing almost everyone reading along) expected it would. It's not warp tough, but considering I cut 8 replacement arms out of 1 $1.70 piece of wood dowel and it took me less time to make and install replacement arms than it did to upload the video from today...I'm pretty happy.

I cut down some of the FC6045 props since Alex has a big box of them. Was easier than I expected and I loved them. Motors stayed cooler and the quad felt great. Unfortunately I fumbled the catch on landing and ended up bending one of them. Since I only cut four down I had to pull them and switch to something else.

I'm going to order some 5045 and some 6030 to try and see if I like any of those or if the cut down 6045 will stay my favorite. I'd rather not have to keep cutting so I'm hoping one of the others will feel good as well.

There's still something causing it to just fall when I come off the throttle in horizon mode. It comes and goes though it seems. Might be the way I have the FC mounted, might need an extra layer of foam and tape to help buffer it a bit better. Flies great in acro mode, but the times I had to switch to horizon to save myself usually it wound up dumping me instead.

With the 6045's on I figured I'd have my best chance to keep up with alex and his warp so I tried to film him air to air flying LOS - as if that had a chance of working. As expected he lost me quickly so I just did some flying around. I have to work out a better mounting location that gets the props out of the photo - but the budget quad lifts a mobius great with almost no jello even though it's just help on with a velcro tie.

Next I tossed on the hat camp and tried the experimental profile I setup. I had raised the P term on roll/pitch/yaw almost 1 each and pushed the rates higher. This actually turned out to be a fun profile! I'll have to check just how I have it setup...getting to the afro to hook to the computer is still a big deal, I need to install a header and the bluetooth module. The flips on this profile are out of this world. It can hang with the warp+KISS in a flip competition no problem!

On another try I pulled off my first acro flip. The hat cam is working great it seems. I keep forgetting I'm in acro...I think that's a good sign :)

I really didn't expect him to listen to me when I told him to try some suicide dives, good thing he flies the warp!

I pulled off a perfect 4 prop crash snapping all four but not breaking anything else:

I thought I had video of the final crash, but I kept forgetting that the mobius turns off after I stop recording and I need to make sure it's actually on before pressing record :(

Other than props this was the only damage:
20140815_202534.jpg
 

Twitchity

Senior Member
Sorry to hear about the quad, and just because I'm a horrible person I have to tease you with another picture of the PDB :D

Also cutting the frames right now...

IMG_20140816_134351_zps0ecdded4.jpg
 

jhitesma

Some guy in the desert
Mentor
That's some skills soldering fullsize leaded resistors to those 0603 pads! Good work! Looks like I got the polarity on the pads right after all too!

Very cool stuff!

Were the power wire holes not big enough? Looks like they're just soldered on top and not actually going into the holes. I was worried I may not have made those big enough....


And yeah, this wasn't a very good morning for the ubmq. Didn't even get through one pack but when through three sets of cut down props broke at least one arm and one motor mount.

Gotta figure out what's causing the death dives when I let off the throttle. I though it was limited to auto-level modes but this morning it was happening in acro :( I spent more time swapping props than I did flying today :(

My best guess is it's vibration related. The FC is just stuck on with one piece of 3M double sided tape foam tape right now, I'll probably remount it like it is in my big quad with two pieces of foam tape with craft foam sandwiched in the middle to see if that helps.

It files great most of the time, but it just gets into this mood sometimes where it tries to flip over an fall as soon as I let off the throttle...If I can figure that out and put a stop to it it will be a fun little budget acro toy.
 

Twitchity

Senior Member
The holes were a little on the small side, but I think I was using 16aug wire so that could have been it too. I don't see there being any problems with 18aug or 20aug, I just didn't have any to use.

Hopefully you'll get that issue sorted out soon. I was able to ge two frames cut today so I can mail you one shortly. I'll throw in some resistors I have since you're appear to be lost somewhere and never to be seem again. Soldering those little LEDs was a complete pain. They looked like a spec of dust on the control board, and I didn't have a magnifying glass.
 
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jhitesma

Some guy in the desert
Mentor
If you think those LED's are bad you should try a STM32 chip ;)

So this morning was frustrating. After last night going so well with the ubmq I was really feeling hyped. Yeah, it had that odd tendency to fall out of the sky when in horizon. But it seemed to be isolated to horizon so I assumed it was probably just auto-level needing some adjustment. And it seemed to happen less if I did a gyro and accel cal just before flying. The repairs last night weren't bad (and with a few easy jigs could be made even easier) but were admittedly more work than repairs on the warp - mostly since the warp generally doesn't need repairs :)

So I had high hopes for flying this morning. It was a touch windy...but it the last weekend Alex is in town and the warp has no issues with the wind...why not see how the ubmq does. Once again it's no warp. It's better than my knuckle in the wind, but it's still not nearly as much fun and more work than the warp.

But I barely clocked a minute of time in the air this morning because the falling out of the sky problem was back - and is not limited to auto-level modes as the crash that grounded me today was in acro.

The first crash I didn't catch on video...or I may have accidentally deleted it...whatever happened it doesn't seem to exist in this reality and I'm not going to pretend it does. What I remember was that again as soon as I started to let off the throttle it suddenly dropped an arm. I'm pretty sure it was the back right arm - but at this point I wasn't paying close attention.

The second crash I did catch on video, you can skip to 00:30 where I actually take off, I'm still working on getting the faster computer back here so I can do some editing:

This was on my experimental profile 3 - but I flew on 3 quite a bit yesterday without this problem. And I've experienced this problem on profiles 1 and 2 as well. The first crash was similar to this only no flips. I was just doing a gentle banked turn - relaxed the throttle a bit, and fell out of the sky. This one I had just let go of the flips and recovered - let back on the throttle a touch - and fell out of the sky.

Third crash did me in for the day:
https://www.youtube.com/watch?v=SU6pBNLabYw&feature=youtu.be

Was flying full acro in profile 1 - my gentlest settings. Was just hovering. Let back on the throttle just a touch - fell from the sky.

None of the videos I have from yesterday where it happened was it close enough to see which arm. But it feels like it's always that same one.

Now for a game of cause or effect. That rear right arm has understandably been taking a good bit of abuse. But that last crash today did more damage than I expected all the same. And I found something that has me wondering if it was from the crash...or if it was the cause of the crashes.

Most apparent damage was visible before I started to disassemble, but this is a better overview to start from visually. The cracked leg is the #1 motor that I'm pretty sure hit the ground first. Screws were not damaged as far as I could tell, just the wood cracked. Don't think my second pin as a fuse idea would have helped here - it hit that arm first on hard ground with some decent momentum:
10602567_10152211647586805_1035381769_o.jpg

And the #2 motor was knocked off the arm entirely. Not surprising since I expected these mounts to let loose in a crash. But it's a bit worse than this photo makes it look:
1070505_10152211651681805_88244369_o.jpg


Oh, yeah...that hurts. Bent both SS mounting screws. Impressive:
10621312_10152211650696805_183278838_o.jpg

Ripped the screw head and part of the plastic card right through, very impressive:
10614700_10152211651581805_319952466_o.jpg

So I made new motor mounts. I thought I had made some spares when I made the first ones...but I can't find them. I may have accidentally tossed them out. That's why I don't normally clean my work table :) This time I tried laminating a card on each side. Thew new mounts are VERY stiff. I can put them on VERY tight and the wood just barely starts to flex while the boom starts to compress pretty well. And the screws just barely poke up past the end of the threads in the motor. So they're just about perfect. Nice little upgrade.

I haven't mentioned it but the motor mounts have been working well it seems - in hard crashes they have shifted and been bumped around but the motors haven't taken any apparent damage. Well, Maybe. This is what I found when I took the #1 motor off to replace it's boom:
10612429_10152211652576805_1909972909_o.jpg

The circlip was loose. Now I don't know if it had come off earlier and was the cause of the problems on that arm...or if it got thrown off in the crash. I did replace this arm last night so that clip must not have been loose when I was having the same diving problems yesterday..but yesterday they were usually recoverable - today it just fell from the sky.

I don't think it's a desync problem because it's happening when I let back the throttle not when I put on the throttle...but I'm not a descync expert or a high kv motor expert. And it does seem to be that one motor that's doing it. I should have marked the one that was a bit goofy out of the box, hindsight bah. Not sure if I'm ready to swap that motor or not. I only have so much shrink wrap and I'm going through it kind of quick replacing arms ;) Whatever it is it definitely seems throttle related - and intermittent. Which really has me thinking vibration....

I was using the cut down props today...but I balanced them after cutting them down and the quad didn't feel or sound like it had any new unusual vibrations.

Well, I've got new stronger motor mounts made and half installed. Have a new arm made and installed (just have to shrink the wrap.) so it's about ready to button up. Putting it off because I should install a programming header, and I really want to pick up a bit of polycarbonate tomorrow because I can't see the LED's on the afromini through the wood. It will also make the big obnoxious square design a bit less obtrusive I hope. And I like clear things.
 

jhitesma

Some guy in the desert
Mentor
The holes were a little on the small side, but I think I was using 16aug wire so that could have been it too. I don't see there being any problems with 18aug or 20aug, I just didn't have any to use.

No, I was hoping it would handle 16, I was afraid the hole wasn't big enough. Just kept forgetting to double check :(

Hopefully you'll get that issue sorted out soon. I was able to ge two frames cut today so I can mail you one shortly. I'll throw in some resistors I have since you're appear to be lost somewhere and never to be seem again. Soldering those little LEDs was a complete pain. They looked like a spec of dust on the control board, and I didn't have a magnifying glass.

Yep, looks like an issue for the next revision. Yeah, no clue what's up with my resistors, tracking just disappeared outside of LA :( I honestly have more problems getting things shipped from CA than China half the time it seems.

Those little 0603 LED's are indeed super tiny. But they were all I could fit between the power wires, and left more room for other things. Plus they were after all mostly for fun :) I will be using a magnifier on mine though ;) I may just order a new tube of paste solder and do them with hot air....
 

jhitesma

Some guy in the desert
Mentor
OK, cut a hole in the top plate and the heat shrink around the afromini, so now I can access the programming header without taking the whole quad apart. It's far from ideal but I'm out of socket pins and 4 position housings so it will have to make due for now.

Took it for a test flight this morning. And again fell out of the sky in acro mode. Grrr.

No damage to the frame, but broke the last of my cut down props. Back to the 5030 gemfans. Bah. But it hasn't fallen out of the sky on them in tests yet this morning.

Swapping props I found that one of the prop adapters wasn't totally tight. That would explain this mornings crash. Still not sure what was up yesterday. After swapping to the wimpy props I haven't had the problem again...we'll see how this goes.

I did a screen shot of the PID's I'm using so far, right now I'm experimenting with throttle midpoints to see if I can take better advantage of the power band on these motors. (I wish baseflight had all of these on one screen like this. I had to do some photoshop to fit these in ;) )

ubmq_profile1.jpg

ubmq_profile2.jpg

ubmq_profile3.jpg


Profile 3 is the one that lets me do the crazy multiple flips but is still very flyable. I'm probably going to bring the PID's from that over to the other tunes. I'd like to setup a low rate profile to see if I can make this tame enough for my wife to try.
 

jhitesma

Some guy in the desert
Mentor
So...what do you guys think. Worth the extra 8g?

10602027_10152213664696805_271167496_o.jpg

10612026_10152213666616805_1167900481_o.jpg

Still flies about the same, still wobbly when I let off throttle to descend. But at least now I can see the holes for the FTDI adapter to hookup and tune - little access hole too so I can get to them. And I can see my LED's now. Though none of them seem to actually do anything, just on all the time. Never blink to acknowledge a profile change or gyro cal or anything....
 

jhitesma

Some guy in the desert
Mentor
Ha! The lexan may have revealed the problem causing my issues!

The whole thing is warped. Hard to get photos to show it....The problem is when I made the initial arms I goofed a little sanding them and they taper down just a bit in the center. With the wood the issue this caused wasn't very obvious. But with the lexan it stands out like a sore thumb. The two new arms I made after Friday nights crashes I didn't sand like that so they're even. So Saturday morning when I went to fly it was worse because now two arms didn't match. Originally they were all equally off so the warp was even, but with only two off the warp is now uneven.

Looks like I'll have to replace the other two arms so all four are even.

Also may widen the holes a tiny bit. They're a very snug fit right now and I think slight missalignments between the holes in the arms and the holes in the plates are making things worse when I snug it up. Slightly larger holes in the arms will also make it easier to adjust them so it looks more square.

First off a peek at the access hole for the FTDI. Those power wires are easily pushed out of the way.
10627632_10152213666881805_840205016_o.jpg

Here's some shots showing the warping:
10612106_10152213696976805_1704222133_o.jpg

10621766_10152213696616805_1539830863_o.jpg

And here's the poorly sanded arms that I believe are causing it.
10602041_10152213696831805_1448946159_o.jpg
 

Twitchity

Senior Member
You really do have a WarpQuad :D Sorry, someone had to say it. I like the clear frame; I always enjoy seeing the internal working bits (that's why I used to have an open air PC case until I got too many HDD's for it to hold). I think the clear acrylic was worth the extra 8g.

How well did the motors hold up to that last nasty crash? I'm going to have to give those settings on profile 2 and 3 a try once I get my quad rebuilt.
 

jhitesma

Some guy in the desert
Mentor
I guess I knew I wanted a warp quad and tried to appease me...just got mixed up and didn't realize a warped quad isn't the same thing :D

And Yeah, I like clear things :D Though despite being in college when Zima came out (not to mention clear pepsi and the other mistakes of the clear beverage craze) I don't think I ever even tried it. Sometimes clear isn't good :) The lexan has held up to a couple of 40ft drops onto pavement though so it seems like strength isn't an issue.

I drilled out the holes in the arms one size bigger last night and that helped get rid of the warp a bit. But not enough. Next I replaced the two original arms that were tapered with new untapered arms. That got rid of even more of the warp...but it's still not as flat as I'd like :( I think I may have to drill out the holes in the Lexan a bit. I've been avoiding that since the plates are so perfect right now...but I think slight miss-alignments between the plate holes and arm holes are what's causing it to warp so making those larger may let it absorb the slop.

It flew fairly well this morning after the latest tweaks...but still like to drop an arm when I let off the throttle :(

Motors are holding up great. There's on that makes a funny squeeking sound every now and then, but I can't reproduce it reliably. I though it was from the shaft rubbing against the wood arm - but I confirmed it's centered over the clearance hole so that doesn't seem to be it. Could just be bad bearings. Either way it's not the motor that took the brunt of the crashes ;)

The #3 profile is my favorite, those rates are a lot of fun and the higher P terms give it a more locked in feel without getting into any oscillations. In fact I think the P can go even higher but I haven't had a chance to really do any tuning yet since I'm trying to fix this warp problem.