SMD LED Sizes

Here's an illustration of the various sizes of SMD LEDs.  They're pretty cheap on ebay.  0603 Soldering tutorial.  Several more on youtube.  I'm trying to figure out what size is best for the Ladybird.

Note: on the back side there's an arrow. The arrow points to the negative wire.



Dimensions:

• 0603. Footprint: 1.60 x 0.80 x 0.40mm.
• 0805. Footprint: 2.00 x 1.25 x 0.80mm.
• 1206. Footprint: 3.20 x 1.60 x 1.10mm.

This is the 1206 data from the ebay vendor:

Electronics You Need To Get Started

Here's pretty much the electronics you'll need to put together your first plane (not counting transmitter/receiver).

Clockwise from upper left:  LiPo battery charger, brushless motor, servos, electronic speed controller (ESC), battery voltage checker, LiPo battery.  In the center are bullet connectors (note the bare wires on the motor) and props.






Here's some notes on how much these things cost, cribbed from an email I sent to MarkV over at the Brain Wagon:

-------------------------------------------------------------------------------------------------------

here's the build list, which I tried to make as complete as possible.  let me know if I left anything off!

everything's from hobbyking.com except for carbon fiber, epp foam, and glue which are from rcfoam.com.  all the numbers are what I paid including shipping.  all the zero items are things i've got excess sitting around from buying bulk quantities.

traditional glue is hot glue, but i like the foamtac coz it's a bit lighter and (imho) more resiliant.  try gluing a couple of pieces of scrap foam together and if it doesn't give you zen tranquility then use hot glue, keeping it as light as possible.

the epp was more expensive than i remembered... it was about $60 for 6 sheets, not 10 as was my recollection.  I'll stop everything off in the morning and we can check out the tx/rx if you've got batteries...


power system

$10.24    1500 kvm, 24 gram "blue wonder" motor
 $1.25    8x4 props (2)
 $8.58    18A ESC
 $0.00    theraband prop saver bands
 $0.19    JST pigtail, ESC side
 $0.72    2mm bullet plugs, male (3) (motor side)
 $0.72    2mm bullet plugs, female (3) (ESC side)
 $0.00    2.5mm heat shrink tubing

body

 $4.00    carbon fiber 3mm
$11.60    9mm 1.9# EPP foam, big sheet
 $0.00    blue velcro

control surface

$0.00    skewers (2)
$1.03    1.5mm pushrod snap connectors (2)
$6.46    9g servos (2)
$0.00    paper clips (2)
$0.29    control horns (2)

misc

$5.50    beacon foamtac glue
$1.19    transmitter strap

batteries

$13.73    2S/3S balance charger
$14.40    3S 500 mAh LiPo batteries (2)

Tx/Rx

tools
    hot glue gun w/ low temp setting (good one here)
    razor blade cutter with lots of sharp blades
    reaming tool or drill if you're careful (for enlarging servo holes)
    jewelry pliers (for pushrod)
    soldering stuff

Easy Star Stabilizer Repair

 You can read the details (and see the video!) over at the Brainwagon, but the tl;dr is that the EZ* lost half the horizontal stabilizer in a crash.  I could tell MarkV felt pretty bad about it, but I told him it would be no problem to get things good as new.

I double-checked on the EZ* RCG thread, and Elapor (the proprietary foam mix that Multiplex uses is CA-safe, and CA is the recommended repair glue.

So, I used a couple of drops of cheapie Harbor Freight CA (10 tubes, $1.80 on sale) and a spritz of HobbyKing kicker and put the stab back to normal.  Total repair time: about 2.5 minutes, including taking the pics.  Don't tell MarkV, I don't even think he noticed a previous repair from where I busted off the vertical stab!

Quadrature Encoding Function

Oddbot has the perfect example here.  He ORs the A and B inputs so that one line can control the interrupt.  And more here.

Telemetry Cable for the 3DRobotics Radio

Here's how to make a telemetry cable for the 3DR Radio.  It's slightly different than the one 3DR sells. The 3DR cable has a 5-pin connector on the radio side.  I like the 6-pin connector with an empty pin because it reduces the number of ways the connector can be incorrectly hooked up to the radio.

If you do much of this kind of stuff, you owe it to yourself to get the most excellent crimping set from Hansen Hobbies.  Here's some notes on cable making in case you're interested:

http://www.hansenhobbies.com/products/connectors/connectorkits/ck_drcck1/
http://eastbay-rc.blogspot.com/2012/05/miles-of-free-servo-wire.html
http://eastbay-rc.blogspot.com/2011/02/crimping-connectors.html

(TODO picture of radio end)
(TODOpicture of APM end)


Cable (4 wires)

Radio          APM       Color
-----          ---       -----
1. GND (BLK)   1. GND    Black
2. CTS            empty
3. 5V          2. 5V     Red
4. RX          3. Tx     White
5. TX          4. Rx     White
6. RTS            empty

Corrugated Carrying Cases

Here's a pretty good supplier that was pointed out to me.  There's tons of them on the Internet, you just need to know what they're called. They come in a couple of size, bundled in packages of 10.

RC Micro World Free Trial

Via rcadvisor, here's a free offer from RC Micro World: Free access to the current issue and past 11 back issues through October 15.

Free Offer link  (username: Neat-Fair, passwd: tempneat)

No foolishness, credit cards, etc.  This will get you logged in and able to download the issues.  A one-year subscription is $24.  The plans are amazing... the image here is a screen shot of a full-size plan.

Atmel Flashing Tool from HobbyKing

Hmm, this could open up quite a few possibilities.  It's a device that presses down over an Atmel microcontroller and makes the proper connections to flash new firmware.  No soldering onto pads!  Looks perfect for flashing ESCs.  You'll need the USBasp device as well.

Atmel Atmega Socket Firmware Flashing Tool
USBasp AVR Programming Device
eXtreme Burner AVR software

HK describes it thusly:

This genius tool makes flashing the Atmel Atmega MCU found in many ESCs or other devices using Atmega processors a walk in the park. No need to solder or create cumbersome clip on devices, simply connect the socket flashing tool to a USBasp AVR device and place the socket over the exposed Atmel MCU! 

Requires: USBasp AVR Programming Device for ATMEL proccessors.  Suits the Following MCU: Atmel Atmega8, Atmega48, Atmega88, Atmega168, Atmega328

• Fits Atmel processors that use the "QFP32" package.
• Doesn't fit AtMega64 used in Turnigy 9x.
• Doesn't work for SiLabs processors.

Here's a video where hummingbirdRPV flashes four ESC's without even removing them from his quad.

Zephyr II Bumper Scan

Just in case you ever need to cut a new bumper, here's a scan.
http://dl.dropbox.com/u/37880/rc/zephyr-ii-bumper.pdf

Disabling the built-in GPS on APM 2

Andreas sent me a note pointing me to the procedure to disable the APM2 built-in GPS.

tl;dr: the disable pin is adjacent to GND.  Short them with a solder blob.

Zephyr II Battery Box

Here's my battery box for the Zii.  I made it for two reasons:

• I needed a bit more room for these 4000 mAh cells, so I trimmed a bit from the front and back of the battery compartment.
• Other people have commented that crashes were crunching up the Zii nose, and that a plywood battery box helps prevent this by transferring the crash energy to the rear of the body where there's more foam to absorb the energy.

Here's the cut I made to the the front and back of the battery compartment.  I made it flush with the leading indentation.

Here's a closeup of the front cut.  Ther was some epoxy sealing a gap... I used my Xacto saw blade to cut through the epoxy.

Here are the five pieces of the box.  I routed out two slits for the battery strap.  I don't have measurements as I just marked the cuts against the opening.

I started with the front and back walls, placing them flush against the front and back foam walls.

Next, the bottom.  It sits flush against the front and back walls.  Don't let those boards ride up -- the sides of the fore and aft boards should butt against the bottom board.  See the illustration below.

Finally the side walls.  Also shown are some hinges that I might use to hold the top hatch on.

Here's the side view of the box.  Be sure that the bottom and sides touch the flat surface of the front and back walls.  this will transfer energy from the front of the plane to the back if you nose in.

JST-DS Walkera 2-Pin Connector

As seen on the Walkera Ladybird (and presumably other Walkera 1S craft).
Vendor is sammylam on ebay. listing here.


Note that some other brand has an identical connector WITH OPPOSITE POLARITY so be very careful in this regard. Here's a nano-tech with opposite polarity.

Update: the polarity of the advertised pigtais looks like it is opposite that of the Walkera Ladybird.

Micro Deans Connectors

Here's the official page.

Polarity Convention:

• + is the male pin on the battery. 
• - is the female pin on the battery.
• + on the speed controller is the female pin (battery side)
• - on the speed controller is the male pin (battery side)

Color Convention:

• Red on batteries
• Black on ESC/charger
• Black plugs harder to get, a lot of people color them with sharpies.

Youtube overview and soldering guide.

Ladybird Dual Rates and Expo

When I replaced my non-binding Ladybird, I took the opportunity to upgrade to the Devo 7 radio.  It's a nice radio but God Almighty it's got a terrible menu system!  It made me dream of the graceful elegance of my Turnigy 9x!

Here's the settings that worked for me.  I couldn't figure out how to use any of the Dual Rate switches, but I was able to finally fiddle with the thing to set these parameters.  Wow Hobbies set the Devo 7 so that one of the switches would toggle between stabilized and acro mode, so I made a copy of the model setting.  For now, I'll just change between models to turn expo on and off.

Pos 0: ELEV D/R - 80% EXP +30%
Pos 0: AILE D/R - 80%, EXP +30%
Pos 0: RUDD D/R - 100% EXP LIN


If I can figure out exactly how I did this, or how to set things so it's switchable I'll update this post.

SmartieParts -- one per Turnigy 9x?

I sent this query off to the SmartieParts people:

 Can I use one SmartieParts board to configure 2 
 Turnigy 9x units? in other words, can I use
 the SmartieParts board to install ER9x or similar
 and then remove the SmartieParts
 board?  (Of course, that 9x unit won't be
 able to take advantage of the enhanced
 LED features.)

And got back this response.  It's pretty good information that I haven't seen elsewhere, so I'm taking the liberty of posting it here.  I ended up not ordering a second 9x, so the issue became moot for me anyways!

(update: after installing my SmartieParts board and getting some experience with it, I find I agree with Steven's notes below.)

Steven writes:

Yes you *can*... but I don't think you *should*.  And its not just because I want to sell more kits :) Honestly... there are good reasons:

1.  Most people quickly realize that they need to update *frequently* because the firmware is in constant development.  There are regular updates (it is slower than it used to be... but still).  Swapping is a pain.
2. The plastic that you're screwing into... it just isn't designed for constant assembly/disassembly.  You'll strip out the plastic eventually.  That goes for both the main case screw holes as well as the risers that my board screws onto.
3. Even if you don't frequently update your firmware... one of the huge benefits of a permanently installed programmer using er9x/eepe combination is that you can easily and quickly define and tweek your models' settings on your computer and transfer them to your radio rather than using the less-intuitive radio menu controls.
4. Similarly, you can hold literally millions of models on your computer but only a handful on your radio.  But with the programmer, all you need is to hook it up via USB and you can transfer whatever models you want at that particular time.

So really... its best to have a permanent connection in each radio.  That's the biggest "complaint" (if you can call it that) people have about my kit is that it is too expensive to outfit it in multiple radios.

At the risk of talking myself out of a sale... I usually advise people with multiple radios to instead buy one cheap-o USBasp programmer and practice up on their soldering skills and solder a permanent connector into each radio and use the one USBasp externally.  See... comparing my $35 programmer to a $10 programmer for one radio is only a $25 difference and that's easily justified by not having to solder and risk damaging the radio... but when you do the math for 2, 3 or 4 radios (or whatever)... now the difference is much larger.  With that said, there are MANY people who have bought multiple kits from me!  There's one guy that has 8 radios and 8 of my kits and he swears by it!

I hope that helps with your decision making.

Steven Morehouse
SmartieParts.com

Arducopter "In The Air" Levelling

Andreas sent me a great overview of the Arducopter "In the Air" leveling correction [update: originally from Danny Thieverge]:

Did you do the "in the air" level? I call it this way because the real name is confusing for some.

Most people do the "bench" level function, this tells to the APM what is suppose to be square and level but we all know that in the air it's a bit different. One motor can be a bit stronger, something is not square (arms)... the Center of Gravity not really center.  The APM will compensate for all this but it's not optimal flight and stability.

the super quick way to get it done is to Arm your motors as usual then hold the arming position for an extra 20-25 seconds.  you will notice the ABC led on the APM will flash differently.

You are now in "auto trim" mode.  This means you have 45 seconds to fly the copter above 4 feet (above ground effect)  and keep it in perfect steady place. (I STRONGLY suggest you practice before so you know where on your radio is the sweet spot for perfect stable in place flight, for example it could be 2mm up on roll and 1mm left on pitch... learn that sweet spot and then land and arm for 20 more seconds)

So now that you are in this mode (only last 45 or so seconds) the APM will "learn" what "trim" (dont trim radio!!) to apply in air and will zero in it's settings.  If you are not in a wind free environment it will not be perfect.

After the 45 seconds you will be back in normal mode of operation so you will see the copter going in that direction that you were holding. Land and try to take off (normally, in your Stab mode)

the experience should be way better.  if not, you land again, hold again arming for 20 sec. trim in the air again for 45 seconds and land, test and repeat.

It only takes 2-3 pass usually for me to get it very very good.

Weekly Miscellanea

Miscellaneous things this week:

• reversing a servo internally. tldr: reverse outside pair of three wires, reverse motor wires
• EasyCAP USB video input.  Good for FPV video capture, $9.  Several other models available. Mac software here and here.   I've got one on order, I'll review it when I get it.
• quad safety tip: toss a towel over the blades to stop them or keep them from spinning up.
• Ali Shan Mao flew the tiny QR LadyBird quad.  Object of intense desire!!
• Ecilop camera mount.  Fully sprung, uses battery as a counterweight.  Nifty!
• Repairing planes with Instamorph shapable plastic.
• Scotch Fasteners for mounting gyros.

Ladybird Prop Bumper

RCG user phoxache made a nice prop bumper.  Cut from 6mm Depron, very nicely done!

Micro JST connector sources.

The first one is connector-only; the others have pigtails of various flavors.
Micro JST 1.25 T-1 2-Pin Connector Plug Female ,Male x 50 Sets
10 x Micro JST 1.25 2-Pin Male , Female Connector plug w/.Wire
Mini. Micro JST Connector plug 1.25 2-Pin w/.Wire x 10 sets
Mini Plug Extention for Micro Battery 10cm (5pcs/bag)

Zii Battery Box

So I cut out a battery box for the Zii... After checking with Andreas, I trimmed the foam on the indentations of the front box at the front and back edges.  White PU for attachment.  I set the front and back boards of the box such that they would transfer shock along the side and bottom boards.  I routed out some battery strap slots (the middle one by hand, in case you can't tell).

Initial box cut, a little bit tall.  I whittled it down with a fresh-bladed box cutter.

Not too bad.  Fits snugly in the slot.

Oh no!!  It's just a bit too narrow for the 3S 3000's!  It's pushing one side out... That will affect the structural integrity in a crash, so I may recut the box.

Here's the batteries snugged in and tied down.  Will talk to Andreas about the best place to put the APM, receiver, and ESC.

Activating Camera Shutter via CHDK

Mark VandeWettering over at Brainwagon gave me a CHDK clue... it's been sitting in my mailbox for a while, so let me get it up here:


It's been a while since I looked at this, but I don't think it's difficult at all. If you look at the "home made usb remote" cable: 

http://chdk.wikia.com/wiki/USB_Remote_Cable 

Basically, if chdk has the usb remote trigger support in it, it monitors V+ on the usb input port, and when it goes high, it triggers the shutter. So, just attach it directly to the arduino GND and any digital pin, and you should be able to trigger the shutter.

And related, Arduino Control for EOS Cameras.

Super-Duper 12-cell, 3-format 1S Charger

I've really loved my Eflight 4-port Celectra charger.  It's portable and does a great job charging Eflight-style 1S batteries.   But, I have a new love now... When I bought both my Ladybird and my HK FP100, they both came with a tiny 2-port charger powered off of USB.  This makes sense, since USB will deliver a 500mA 5V current, just right for charging two 1S cells.  I wanted to do the same for the eflight-style batteries.

So, I ordered an extra FP100 charger (less than $3!) and soldered in some eflight charging leads.  It was easier than I thought.  I didn't need to unsolder the FP100 connector from the board; instead they were perfectly sized and positioned to be solder pads for the cables. I did open the case to do the soldering though, so I wouldn't have to be so precise in navigating the soldering iron in the plastic case.

After soldering I put the case back together.  Line up the tabs on the FP100 connector or you will bend the heck out of them.  You could do the same thing with the Walkera charger, but those run about $8 Stateside, and HK is perpetually out of stock.  If I can find some Walkera leads (with the right polarity!!) I might make a version for them using the FP100 charger.

Here's the final goal: a 12-battery 1S supercharger, capable of handling four each of three different styles of connectors: eflight, walkera, and HobbyKing FP100.

I've hot glued the chargers to an old USB hub, and will power the hub from a wall wart power supply.  I think I'll be able to fit six of the chargers onto this particular model.  I wish I could find some 3 inch cables!  If I were to go totally insane on this project, I would eliminate the connectors and directly solder the power leads.

  I'll check the amp rating on the hub and power supply to see if it will charge 12 batteries simultaneously at full power;  It would be cool if it did, but I imagine I won't be needing to do that very often.

S107g helicopter control via Arduino

Here's an interesting article by Andrew J. Barry that talks about controlling the ubiquitous Syma heli with an IR LED connected to an Arduino.  Source code included to fly by keyboard!  More discussion at RCGroups.

EzFly on 2S LiPo

Thanks to Andreas, I finally have a decent video of the EzFly.  This video is with 2S.  3S performs better, and cuts through the wind nicely!

blogodex = {"toc" : "EZFly", "idx" : ["2S battery"]};

FlySky Compatible Transmitters

Apropos the $18 quad, mystman posted a list of FlySky compatible transmitters.  There's another post for the FlySky JR module.

dave1993's $18 micro-quad

Well this is pretty amazing! dave1993 has put together a microquad for $18.  He's posting more photos and details, but here's what I've gleaned from the thread so far.

• control board: V929-06 Beetle, SKU:SKU037759, $13
• motors: 716 coreless brushed, 10 pack for $8.90 specify 1mm shaft as per instructions
• blades: Ladybird spares, SKU:3xSKU036330, 3 sets for $6
• bamboo frame
• motor holders
• Rx is FlySky compatible

More details to come.  Dave says

"I've built 4 of these so far ranging from 6" (1/4 bamboo sticks) up to 24" (1 bamboo stick per arm). the little one is kinda "frisky" and the big one is too floppy so 12" (half stick per arm) seems a good compromise." [that's 12" motor to motor]"

update: Dave says:

"holders are simply small paper tubes held on with polyurethane (gorilla glue) foam. it weighs almost nothing and is as strong as all getout. in the photo you can see this is reinforced with a triangle of wood tongue depressor which is also used for the center hub. the whole frame costs about a nickel and only takes a few minutes of your time.

havent damaged one yet after many many (have i mentioned many?) crashes so this seems to be working out. i learned about the zip tie legs in the v929 threads and that looks like a great idea too. keeps the quad up off the ground on less than ideal surface and also contributes to unbreakability. and holds the motors in too as youll see when i get better pics."

For Spektrum compatibility, you can use a Blade MQX board. It's more expensive, but cheaper than getting a new transmitter.  Here's one for about $36. 

Turnigy 9x Elevon Mixing

 Later I'll add some more verbiage and perhaps even make a video, but for now here's the two screens you need to fiddle with in order to get Elevon mixing going on a Turnigy 9x.

First, set the aileron endpoints to 120% in each direction.  Move the aileron stick left and right to get to the two numbers.

[update: I thought I got this idea from Andreas, but he sent me an email asking about this and claiming never to have done it.  Did I hear about it on RCG?  Make it up out of whole cloth?  Investigation forthcoming!]

Once you've got the endpoints set, go to the Elevon menu and set it to look something like this.  Depending on how your servos are installed, swap the values 100 and -100 until you get things right.

Here's what Elevon mixing does, and how it's calculated.




This space reserved for a video of this.  Will Mark get to it?  The suspense will kill you!
Update: yes he did!

Test post for indexing

foo bar caption

This is a test post for indexing.  But while you're busy ignoring this, check out the automated master index!

A Genuine Spektrum Battery Case!

 And another one for Crash!  Like most people, I've been keeping my 1S batteries in old medicine bottles.  It works well, but I'm not able to keep track of which batteries get used more often... I just shake one out and plug it in.

So, when I was given these 6x4 event cards that actually said Spektrum, I knew what I had to do!

 The idea was simple... cut out some strips from foam scraps sitting around, and make a wallet-style case for the batteries.  These were made from some 9mm EPP I had in the scrap bin.  I think just about anything would work.

I hot glued some thicker strips around the three edges, using the batteries as width guides.

 As you can tell, I cut the strips out freehand.  I glued some little squares at the top as stoppers.  I was going to glue these down lower, but the batteries don't seem to shift around very much.  I might glue in some more squares between the batteries so they don't bump their connectors together (update: did this, works well!).  I might use a sharpie to mark the battery sizes as well.  This should make it easy to rotate my batteries consistently.

 I used some clear tape to make a hinge and attach another card on top.  It fit OK, but would have been better if I had been more careful (actually less stingy -- didn't want to waste the scrap!) cutting the bottom piece.

 A thing of beauty is a joy forever!  Since this is a Crash-inspired piece, I'll just point out what an awesome job could be done if somebody printed the foam insert with a Phlat Printer.

It seems to work pretty well.  I'll use piece of blue tape to seal it up, or maybe just lay it flat in my indoor flight box and see if everything holds together.  Anyways, I love having a genuine Spektrum battery case, and I'm sure I'll get some comments from the guys at the next indoor fun fly.

Thanks again Crash, I don't think I would have bothered with this if not for you!

PS, if you like the artwork on the postcard, check out the exhibition running from July 19 - September 13, 2012 at Gallery Carte Blanche!