Under 250, Under 250, Under 250!!!

[Craftydan]

Home again, home again, jiggidy jig . . .

when last we left off, the flying part of the quad was up and running, and minus a few cleanup points (final battery connector and covering exposed connections) she's "airworthy" . . . but No FPV.

Honest, I'm not trying to steal your tiny soul.

So next we pull out the camera, and like everything else, by necessity . . . it's TINY!



First things first, that cable will need to go. Hooked it up to test and determined the cable and mic are on the bottom of the camera. Good to know.

Space will be a bit tight for all that wire, so off it comes



Keep in mind, it's red (power), Yellow(Video), Black (ground), with Red nearest it's regulator. The white audio wire is left disconnected. Audio in FPV is pretty much a waste of bandwidth, particularly for multirotors. You'll get a cleaner signal off the video if audio is grounded, so I'm striping it off.

First version I did de-soldered the mic too. Second one I left it on. Mistake. In the next post, we'll mount it on the frame and leaving it on will prevent us from leaning the camera back for "warp speed".

Polarity strikes again!

If you recall from much earlier, the first camera got burned out from having a reversed polarity. since these connectors aren't hot-swapped, this is easy to fix via keying. effectively I add a pin to near middle, and fill it so the plug can't be plugged into it backwards.

First, to key, let's cut the key pin:



take care to save the little bit we cut off. We're going to use it to fill the keyed hole on the female side.



Slide it in and use the male side to press it into the connector. Viola! Now she's keyed.



Now if I press the male in misaligned to the keyed slot, the connector won't seat and I know I'm doing something wrong.



What's life without Connectors? Disconnected.

Now that we have a ghost of a chance to prevent reversing polarity, time to mount the header to the back of the camera.

First we prep it. Bend all the pins 90^o to the mount. one advantage to these round milled pins is they can twist in their mount. twist all three pins so they match the pad spacing on the camera and trim them so they'll land flat on the pads.



solder pads are on the bottom and we want the connection form the top, so up and over the board it is. Spacing is tight so a touch of careful alignment . . .



. . . and a bit of magnification is called for:



flux, tin, tap 3 times and . . .



The camera is ready to mount into the frame . . . but more on that later . . . hopefully later tonight.

 

[Craftydan]

So I'm back, and where I left off, the camera was prepped for mounting . . .

So what? Cameras don't just hang from Space!!!

Time to build a camera mount to hold it firmly-ish to the frame. I stumbled into this trick while problem solving a mount on a past build,and it worked surprisingly well for a semi-rigid mount -- hard enough to hold it in place, malleable enough to be easy to shape, flexible enough that it can be adjusted as needed.

. . . and did I mention cheap?!? They just GIVE this stuff away:



That's a flat rectangular strip of a plastic blister-packaging. In this case, a cookie package from a local supermarket, but anything with enough thickness to be stiff will do.

First things first. Let's measure:



Critical dimension is the width, and outside edge of post-to-post is about 1" (0.953 with the hexagon edges the farthest out . . . but I'm happy to round up). Height is about 0.83", width of the post is .25" . . . so if I'm going to make a C-shaped mount, I'll need at minimum 0.83" + 2x0.25" . . . so 2" is more than enough -- I cut a strip 1"x>2" and trim excess as needed.

Nice part about clear plastic, you can set it on the grid and cut the straight edges right on top. First pass, just score (plastic is less likely to slip):



Then trim and break off the excess (I suppose 1x3.5" is longer than 1x2")



Raw stock to new bracket . . .

So next we'll use a ruler like a sheet-metal break and measure out 0.25" for one side's "under the post" tabs. Be careful to keep the bend square to the length of the plastic and to the fold.



Next lay it over the holes in the frame and mark the centers.



Drill a pilot hole in each . . .



. . . and time to make the holes wider, with the right tool for the job, a reamer. The goal is to make it Just wide enough the bolts can slip through without catching on the threads.

Keep in mind, with soft plastics like this, the conical shape of the reamer will cause the hole to grow a bit of a cone shape as the plastic weakens and stretches. Switch sides every 4 or so twists to even the cut out from the other side.



When two holes are cut, mount it on the frame with the posts, align the posts flat to the plastic, then use the tops of the post to make the upper edge:



Mark, drill and ream out two more holes for the top side (Just pointing out the obvious . . . don't ream *into* the posts. we don't want to hog out the threads inside)



Next take the mount off and using a scribe (I used a T-pin) and a straight edge, mark two lines on the flat part the camera will mount to, each going from corner to corner. They meet in the middle, and that's where we drill.



Pop a pilot hole in, and ream out the hole until the lens barely fits through.



Stuck on you Like Superglue . . .

So to attach it, my glue of choice for this task: Thin odorless CA and kicker.

The CA holds it in place with minimum fumes and the kicker keeps any remaining fumes from etching the lens. One drop under each corner from the back side, and a shot of kicker from both sides . . .



And we're set trim the excess off leaving ~1/2"



Wait, on the bottom you left 1/4", why 1/2"?!?

Simple. we use the holes we've already drilled for normal flight . . .



. . . Or we can drill a second set of holes further out for "Warp Speed"



we'll clean up the tab on the front later, adding the extra holes and trimming excess that gets into view, but for now . . .



The Camera is mounted!!!

So, Have you said anything about Test?!?

. . . and here's the rub. I don't have a harness to test this wired, so I've got to get the VTX running to test the pair . . . but before that, we've got additional power issues to settle . . .

. . . but more on that later . . .

 

[AdamV]

cool camera mount idea - i think i'll try to copy it! I spent the better part of 4 hours trying to flash my tornado FC and got nowhere. Tried on 2 laptops (vista & XP) and a macbook air and couldn't get it to communicate. My usual desktop (windows 10) has a bum power supply. Read about 30 pages of RC groups Tornado FC, followed all the instructions and got nowhere! I'm about ready to hit it with a hammer. I simply cant get cleanflight to connect so i can load firmware.

 

[AdamV]

i finished the build! I used taller standoffs to fit everything inside so i could put battery on top. I'm sure it's doable with smaller standoffs, but i don't think it is with my components.

I then realized that i'm gonna have to move my 5.8 antenna - it's currently sticking out the back like my HMB235, only with this size it's gonna get hit by props.... unfortunately i cut wires pretty short to the the vtx to keep things clean, so i'll probably have to re-wire it to move it appropriately

Any pics yet of where your vtx/antenna are gonna sit in their final position?

 

[Craftydan]

yeah, had a lot of head-scratching myself about where the VTX goes while laying everything out, and finally gave up mounting it under the deck. just not enough space for the antenna without mounting it in bad places.

I'm running a little short on time -- the Big swap meet is this weekend so I've got to get these done. The write-up will come eventually, but not yet. lemme hit a few high points for you. Here's a pic of #1:



VTX is on the top with a regulator set to 6v -- this VTX has some overheating issues with it's on-board regulator, so after down-regulating to 6v, it's cool enough to keep running the whole flight. A compromise to prevent replacing the VTX, but it works.

. . . and the broken prop?

Lets just say it was a fun evening:

Lost two props in that crash, but nothing else.(unfortunately, I'm out, and have to switch to spares that just came in, but aren't balanced yet).

Not the first set I've destroyed. took it to the club field this weekend to stretch it's legs, and ended up hitting a metal pole . . .

*DING*

Sounded like an Aluminum bat hitting a home run.

The Damage?



that slight dent and one prop.

Yeah. I'm pleased with how she's holding up.

 

[The-One-Who-Never-Crashes]

Has anyone built (or seen) the RMRC Hellbender 122? Looks like a cute little quad.

http://www.readymaderc.com/store/index.php?main_page=product_info&cPath=76_729_761&products_id=5033.

 

[jipp]

great build

 

[nilsen]

great build

You're back!

 

[jipp]

You're back!

yeah, i hope. for some reason this forum would not let me log on.

but hey im back now, woohoo.

chris.

 

[AdamV]

well.... i ruined my satellite connection on the tornado fiddling with it after i had it working.... so i used a ppm connection... but i couldn't get the channels working, so i started trying different spots for PPM on my receiver (dumb!), which ended up in my board smoking after i plugged, presumably backwards into a satellite spot.... lol

But no fear! i had an old naze32 board which i thought was ruined when i pad pulled off (where the PWM stuff goes, but i I still had the pad i needed to hook it up to satellite) Soooo, after a very late night, i should be verrrryyy close to having this done.

Should get it done soon.

Are you using cleanflight? Betaflight?

 

[Craftydan]

Cleanflight.

Betaflight tends to get the new toys first, but "new" doesn't always mean "fun" or "useful". Within a month or two, the features that show value ("fun" and/or "useful") make it into Cleanflight.

Personally, I'm not in bleeding edge competition, so unless I'm in desperate need of a feature Betaflight just implemented, Cleanflight will meet my needs.

 

[jipp]

i have a question for you.. how many firmwares are there for the naze, cleanflight, betaflight, i think iv read of something called raceflight.

it gets confusing.. im to stupid to use naze, so im just using the cc3d. in july that changed from Open Pilot to LibrePilot..

its trippy how fast things change.

chris.

 

[trevoof]

Great project Craftydan, I didn't think it was feasible when I first thought about it - definitely showed me what good engineering ingenuity can do!

What's the final AUW?

 

[Shelak]

It's looking amazing!!
I've been looking for options to modify my nano qx and after that I want to build my own grasshopper! It's amazing!

 

[Craftydan]

i have a question for you.. how many firmwares are there for the naze, cleanflight, betaflight, i think iv read of something called raceflight.

it gets confusing.. im to stupid to use naze, so im just using the cc3d. in july that changed from Open Pilot to LibrePilot..

its trippy how fast things change.

chris.

I . . . . dunno. I know about the three you've mentioned. Raceflight is new to me, but not surprising -- it's not hard to fork an open source project. To make matters more confusing, you can get TauLabs, and dRohin ROMS for the Naze32 boards -- two OpenPilot forks . . . not to mention the CC3D boards can run Cleanflight or BetaFlight, so long as you have an FTDI module -- the latest versions of *flight ROMs are too large to keep the OP bootloader around, so it's gotta be flashed the hard way.

For flavors, there's plenty to try, and most have their pluses and minuses, but nearly all can be made to fly well . . . and the active build teams keep sharing code, so as soon as one has a feature, it's a matter of months before all the active ones do too.

Trippy indeed

What's the final AUW?

With a 75.5g pack, they're all *ahem* hovering in the low 230's. Ironically, the three quads came out 231g, 232g and 233g . . . so a fair amount of headroom to add an 15g to the pack . . . not sure there is a good +40C 3S 1000mAh pack that light, but it's possible.

Got some decent flights out tonight. I'll post 'em when they're up

 

[PsyBorg]

I cant wait to see these in the air.. if you can at that size while zooming around somewhere. Pretty sure the maidens aren't done in the living room or dining room.

 

[Craftydan]

Ok, got one up.

A nice 2S flight. Gives you a taste of the energy behind this guy, tamed down for my dumb-thumbs

I've got a 3S flight in the wings, and quite a few . . . brief 3S flights, like the one I posted earlier. Fun, fully under control, but there is some skill at play in threading the needle.

 

[cranialrectosis]

Nice one, Dan. Love how the tiny copters thread the needle.

Great thread.

 

[AdamV]

All finished! Oddly, the camera gave me fits, until i stumble on post with similar problems which were solved by disconnecting the audio wire. Well, that fixed my issue! It's not super pretty or incredible well organized, but it all fit in there. Should get a real maiden in soon.

Used your camera mounting technique


Hoping my battery/antenna doesn't mess up my satellite reception

 

[AdamV]

Dan, mind if I try out your cleanflight PIDs? I for the life of me cannot get this thing to land with it violently bouncing and flipping. I'm though a dozen props and i haven't really even flown it yet! Having trouble getting air mode to actually shut off, regardless of my switch settings and think i'll just run cleanflight if it's working well for you!