Black Sheep Eats Tasty Crow

(updates)

• Somebody asked "what's a Trappy?" Answers here, here, and especially here.
• Trappy posted a nice note congratulating Andreas.  Just another reason we're both such big fans!

Hmmm, it looks like TBS lost a challenge. We put a bet out that it's not possible to build a frame from scratch within 1 hour (from zero to flying). Andreas Oesterer rose to the challenge and looks like he had 10 minutes to spare! Congratulations, the free TBS DISCOVERY shall be in the mail soon!
Any TBS DISCOVERY builders out there that can help us regain our confidence levels? Can we do it in half the time? The sheep has been served ... but we shall rise from the ashes :) The NAZA RTF sets will ship very soon, with this it should be possible in half the time!

(end updates)

So following an interesting discussion on Facebook, Trappy made Andreas an interesting offer:  If Andreas could build one of his signature wooden quads from scratch to flying, Trappy would send Andreas one of his nifty new TBS DISCOVERY frames.

Here's the result!
tl;dr: finished build in 49 minutes, in the air in 51 minutes.  Watch the videos at the end to see the entire build; The pictures below show some details of the finished quad.

Here's the body templates:  quad, hex, octo.

Arm 4, which rotates clockwise.  The ESC is on the side.  The wood is 3/4 inch Fir.

The prop spinners are nice feet when you've got the quad upside down.  Two bolts are plenty strong to hold the motor securely.








APC props are sturdy and well balanced.  Andreas manfully used needle-nose pliers to tighten his spinners.  You can use a small screwdriver if you like.

The APM sits on top of a piece of foam recycled from a box holding a piece of electronics equipment.  It's cut to the approximate size of the autopilot.

Foam pad attached to the top plate with hot glue.

The autopilot is attached to the foam pad with bamboo skewers.  Coat the top of the skewer with hot glue, and then stick the skewer through the hole.  When the glue sets, snip the skewer to a convenient length.  The hot glue holds the autopilot onto the skewer; the skewer sticks into the foam and keeps its position.  The velcro strip holds the autopilot onto the top plate.

Here's the power distribution spider.  It's based on this design and uses Wago connectors to connect the wires.

Here's a closeup at another angle.

The battery carrier is coated with some hot glue.  The hot glue is less slippery than the bare wood, and keeps the battery stable in the mount.  Use the high heat setting.

The top plate is used to make a flat surface for the autopilot and other things on the top of the quad.  You could skip the top plate if you cut some divots in your autopilot foam pad so it's not skewed by the bolt heads.  The wood for the plates is 5mm ply.

Andreas didn't do it for this video, but it's a good idea to put a helmet of some sort over the autopilot.



If you want to, you can tidy up the wiring by drilling some extra holes and running the wires through the inside of the body.

Here's the videos.  First is a time lapse, and then the build.  I edited it a bit to get the time down to about 45 minutes.  If you've seen one arm drilled, you've seem them all drilled!

Detailed Video, Part 1:

Detailed Video, Part 2:

Build-a-Quad Kit

I received a couple of emails asking about building a quad, and how much it would cost in parts to do it yourself rather than buying a ready-to-fly model.

Here's a HobbyKing based shopping list.  I think it's pretty feasible, a lot easier than building a plane since there's no moving parts.  You will need some basic soldering to put connectors on the speed controller.

Executive summary:  quad parts, about $230 including shipping.  radio and charger, about $100.


Frame and Power Distribution.  There's a lot of latitude in the frame.  You can make one out of old boards and plywood for almost free.  This is a popular frame and good for a first unit.  The power distribution board lets you easily hook up the speed controllers to the battery. 

      $20   Hobbyking X550 Glass Fiber Quadcopter Frame 550mm
      $ 4    Hobby King Quadcopter Power Distribution Board

Power System.  This includes the motor and motor controller.  You will need four of each.  The NTM motors need an accessory kit for mounting (thanks to Andreas for catching this!)
      $40   (four) HobbyKing 20A BlueSeries Brushless Speed Controller
      $64   (four) NTM Prop Drive 28-26 1350KV / 310W
      $ 8   (four) NTM Prop Drive 35 Series Accessory Pack
           
Control Board.  There are lots of options for control boards.  This is one of the simplest and cheapest.  It's good, but doesn't have stabilized mode.  It's what I started with, except when I bought mine it was $150!  See below for other options.  You'll need the programming cable if you ever want to update the programming.
      $20   HobbyKing Multi-Rotor Control Board V3.0 (Atmega328 PA)
      $ 5   USBasp AVR Programming Device for ATMEL proccessors

Batteries.  If you're in the US, it will probably be cheaper (counting shipping) to order separately from the US warehouse. You will probably want two to begin with.
      $19   Turnigy nano-tech 2200mah 3S 35~70C Lipo Pack

            Turnigy nano-tech 2200mah 3S 35~70C Lipo Pack (USA Warehouse)

Props.  You need two each "normal" props and two each "reverse" props.  It doesn't hurt to get an extra bag of each, as they are the thing which you will break most frequently as you learn to fly.

      $ 3   Slow Fly Electric Prop 8045R SF (4 pc)

      $ 3   Slow Fly Electric Prop 8045 SF (4 pc - Green)

Connectors.  If you get the motors and power distribution board above, you will need two packages of this connector for your speed controllers.

      $ 4   (two) PolyMax 3.5mm Gold Connectors 10 PAIRS (20PC)

Shipping.  I'm estimating about $30-$40 or so for all of this.

Other items you will need.  Once you have a battery charger and radio you are good to go on the ground side.


Battery Charger.  These come in all sizes and price ranges.  These are three units that I have personal experience with.
      $12    Turnigy 2S 3S Balance Charger. Direct 110/240v Input

             At the low end... plugs into wall, works well but wil

             take about 4 hours to recharge the batteries above.

      $25    hexTronik Balancer/Charger Dual Charge Capable

             Needs to be plugged into your car or an external

             12V power converter.  Will charge in about 1.5 hours.

      $33    Turnigy MAX80W 7A Lithium Polymer Battery Charger

             Needs to be plugged into your car or an external

             12V power converter.  Will charge in about 30 minutes

Transmitter/Receiver.  Tons to choose from.  The 9x is a nice low-price unit.  It comes with a receiver; extras are about $10 each.  You want a "mode 2" which means the throttle is on the left stick.  These are frequently on backorder.  The Internet believes there's a new model coming.

      $55    Turnigy 9X 9Ch Transmitter w/ Module & 8ch Receiver

Camera Mount.  This one is designed for the X550 above.
      $13    Hobbyking X550 Glass Fiber Tilt Camera Mount

Aeryon Scout used to help guide tanker to Nome

Nice looking quad, the Aeryon Scout, used to survey the harbor in Nome following 27 ft snowfall.  The Internet claims it runs about $30k - $50k.  More here.

Quad laser motor balancing

Basic idea: attach mirror to the quad arm, shine a laser beam reflected onto a wall.  Vibrations show up as a line, when the reflected later light is a point you're perfectly balanced.  Very clever!