Quadcopter Scarab – Power Distribution lead
These photos show the power distribution lead made as per the instructions that come with the Scarab 12 - Quad-X Euro frame. The wire is 20 AWG from HobbyKing. About 15mm of the silicon jacket is stripped from the end of five wires per polarity (red & black). Then the bare wire of each group of five is twisted together. Some 5mm heatshrink helped keep the leads together while being soldered. The result fitted nicely into the terminals of an XT60 connector. I used four micro-deans at the other end to connect to the ESC and one JST connector to hookup some strip LEDs.
QuadCopter SCARAB – Motor Mount Retainer
These photos show the retaining screw cut to 7mm and how it penetrates one quadrant of the 12mm aluminium tube divided up by the motor mount. Cut to the right length, it doesn't intrude far enough to cause concern with rubbing on the wire from the ESC to the motor which is routed internally along the tube.
QuadCopter SCARAB 12 – Assembly part 2
The frame looks well laid out, light weight and just plain good looking. 20AWG is used to connect to the 2213N 800Kv Brushless Motors with just enough left hanging out the end to connect the four speed controllers ( TURNIGY Plush 12amp (2A BEC) BESC ). The only thing I'm unsure about so far is the sorta sharp edges of the aluminium booms and how that might rub against the wires.
SCARAB 12 – Quad-X EURO Build – Motor Mounts
I'm going to try using 1.5mm cable ties on the motor mounts. Seemed to work fine on the Tricopter and in the event of a crash, there might be some give before things get bent.
Canola from the air
It seems every second field is full of Canola around Shepparton at the moment. Here's a few quick ones I took on the way to the Mammoth Scale Fly In at the Valley Radio Flyers.
I did lose the quad once, quite deep in the canola field and thought I could be searching for quite a while but I took the transmitter with me while searching and gave the throttle a little blip every now and again and found it fairly easily.
GoPro Hero, External LiPo power
I recently tried my hand at making a timelapse video using the GoPro (http://www.youtube.com/watch?v=rO3IPMI9TEI) video and still image functions. I was a bit disappointed with the battery life and because I didn't have a spare battery, or access to power the device via a USB charger.
I needed a portable power supply to plug in via USB port on the side of the GoPro. To this end I took a UBEC, hooked it up to the balance tap of a 3S lipo and the output to a USB cable. In the photo below, I added the HK Wattmeter to see if I could measure any current draw by the GoPro. The lowest resolution of the Wattmeter is 100mA and didn't register.
Next to do is maybe add a voltage detector so I can leave it running and get an audible warning if the LiPo gets low however I hope a 2650mAH battery will outlast a 32GB SD card in the camera. I'll have to hook up a proper multimeter and measure the average current draw and figure out how long batteries might last. Maybe integrate a low voltage cut-off circuit as well.
$20 Quadcopter frame, test flight video
The $20 Bunnings quadcopter frame is a bit heavy, about 400 grams but its straight and strong. The control board is a MWC Paris V4 board with WM+, BMA180 and BMP085 sensors. All up weight is about 1300 grams with the 2650mAH nano-tech 3S lipo. Flight time just hovering was 10-11 minutes.
http://www.youtube.com/watch?v=WzN8wmxWW2s
Connecting the BMP085 Baro to the MultiWiicopter Paris V4
The BMP085 Barometric Pressure sensor is mounted on the bottom side of the Paris V4 board. Orientation of the BMP085 is not important but vibration is always an enemy so I used double sided foam tape to mount it. There are four points from the BMP085 that must be connected, VCC, GND, SDA and SCL. In this case they're connected to the LV I2C pads on the bottom side of board to the same points that the BMA180 Acceleromter is connected to on the top
Yellow wire is SCL. White wire is SDA. Red VCC and Black GND.
Photos of flashing the HobbyKing Quadcontroller
Just a couple of photos showing a 3S 2200 powering a BEC powering the Hobbyking Quadcontroller board connected to a USBasp Atmel Programmer connected to a Windows XP machine running the KK Multicopter Flash tool.
How to update the HobbyKing QuadController firmware
The HobbyKing QuadController board retails for about $30 USD. You can save a few bucks by checking for a buddy code on the swarm page. The board forms the base of building a cheap multirotor.
By default the board comes with some version of firmware pre-configured for +Copter. The problem is, I don't know anything about the origin or version of the pre-loaded firmware. The HK manual goes into lengthy detail on how to update the firmware before it even shows how to mount and use the board so I guess it's assumed, if not recommended to update the board before use? A lot of people won't like the default + configuration and to fly in the X config, or even Tricopter config for that matter, a firmware flash is required.
As usual, the hardware and software I have doesn't match that used in the manual so of course I can't simply follow the instructions step by step. Life wasn't meant to be easy. For a start, my Atmel USB programmer wasn't the same and wasn't recognised by the software mentioned in the manual "AVR Studio 4". The programmer I bought on eBay is called a "USBASP USBISP AVR Programmer USB ATMEGA8 ATMEGA128". More info (drivers etc http://www.fischl.de/usbasp/) Now this is a 10 PIN device and of course the HK board has a six pin interface so you'll need one of these "10PIN to 6PIN ISP Adapter board for ATMEL AVRISP USBASP" to be able to plug it into the board.
The next problem to overcome is the AVR Studio 4 software not recognising my USB programming interface. This is where the "KK Multicopter Flash tool" comes in handy. Not only does it recognise my programmer, it puts a nice GUI frontend on the AVRDUDE software and automatically shows a list of compatible firmwares for the HK board. Just select the one you want and it will download it. The software author makes mention on his page that the HK board comes in a state that protects the firmware can't be overwritten and he also gives the specific command required to unlock it.
Once that's done open the Flash tool (java required), select Programmer: usbasp (USBasp, http://www.fischl.de/usbasp/), Controller: Hobbyking Quadcopter Control Board (4kB flash) and select the firmware flavour you want to use.
I had to copy the contents of the folder "...kkmulticopterflashtool_0.21\lib\avrdude\windows" to a new folder I created "C:\WinAVR\bin" because the KK Flash Tool assumes WinAVR is installed in that path.
Hit the little green running man button and away it goes. All going well it should end with a message something like "...flash verified. avrdude.exe done. Thank you."
Next step, mount it and fly.