QuadcopterAmraam

Plan

Some time ago I had a hobby more related to my nick, modelrockets. I made a few and launched a few, all low power. Then I started to make a payload with a height meter that sends the height and max height live to a ground station. Made with 2 arduino's, a Duemilanove for the groundstation and a smaller one (the JeeNode) in the rocket. The Jeenode has a little transmitter, but that was too slow for the speed of a modelrocket, so I use XBee's as tranceivers.

Information on that project can be found here : https://code.google.com/p/rocket-telemetry/

Long story short, I quit making and launching modelrockets and threw/gave the rocket stuff away except for the height module (and a camera module).

Now my goal is to use these payloads with a quadcopter. My version will be made so that it supports the payload segment, suspended below the quadcopter.

Materials

I already bought some stuff :

- Hobby King X580 Glass Fiber Quadcopter Frame w/ Camera Mount 585mm (1x)
- Turnigy 2200 mAh 3s 20C Lipo pack (2x)
- Turnigy Batterystrap 300mm (3x)
- Hobby King Quadcopter power distribution board max 20A (1x)
- NTM Prop Drive 28 series Accessory pack (5x)
- Turnigy Multistar 20 Amp Multi-rotor Brushless ESC 2-4S (5x)
- NTM Prop Drive 28-26 1000Kv / 235 W Short shaft version Outrunner (5x)
- Hobby King i86 Multi-Rotor Control Board (Atmega168PA) (1x) from rc-addict.nl
- 9x5 Propellors standard (3x)
- 9x5 Propellors counter (3x)

Still en route from Hong Kong :

- KK2.1 flight controller
- more propellors (standard and counter)

Things I already had :

- Jamara FCX6 receiver with transmitter 6 channels
- T2M Wizard X65 charger/discharger

Notable things during assembly

First the frame, it is made of glassfiber and there where some small splinters at the edges, very small, but you still feel them so I used rubber gloves during assembly of the frame. It has an extra plate to mount a camera (size and weight of a GoPro)

The motors are shaftless so you have to buy a Prop accessory pack to fit the propellors. The center hole in the props I bought at rc-addicts where to small so I had to drill a bigger hole in it. Best done with a kolom boor. The was no specific reason to buy shaftless versions. They had the thrust I wanted.

Testing

After the copter was build I did some tests to see if it all worked.

Rotation (with rudder, horizontal movement of left stick in mode 2) was reversed, so pushing the stick left made the quadcopter rotate right and the other way arround. Solution was to reverse the rudder in the transmitter.

click for a bigger version

No liftoff with full thrust applied. Cause in my case : all the propellors where turning in the same direction, counter clockwise. So two propellors where pushing the quadcopter down and two where pushing up, so they basically cancelled each other out and apart from a lot of noise and moving air the quad stayed put (while slowly rotating clockwise). Solution in my case was to reverse the connectors to the two counter clockwise engines at the motor side. So put the black (ground) wire in the red (plus) wire connector and the red (plus) wire into the black (ground) connector. For me this fixed the problem.

Flying

Not really flying, attempting to fly. The HobbyKing i86 board isn't very stable, combined with my low flying experience this breaks propellors. So having lots of propellors is really useful when you begin with flying Quadcopters (as Justa said during his presentation). Today (29th Dec) I went to a big parking lot close to my home and tried it out. I was able to get it off the ground, and while the Quadcopter was below 1 meter it went okay, there was enough time to cut the throttle without harming propellors when I was about to lose control. At the last attemp it accidently went higher (to 3 meters) and the wind caught the Quadcopter and moved it away from me so I throttled down after which it went down in an elegant curve, destroying two propellors.

images

Heigth

groundstation payloadbay payload

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Mountingpoints

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