Build diary - Q650 Frame Quad with ArduPilot

[DarrenG]

First pics of the frame which arrived today.  A Q650 from UnmannedTech. Going to document the build as it progresses over the next few weeks.

Frame builds easily and looks great. Time will tell if it';s up to taking the knocks that I will doubtless be subjecting it too!

I';ve also drilled the cover for the nav light kit that I bought.

[peter_a]

Nice , I was looking to build the hexacopter  version ( Q800 ) , but decided to go for something much cheaper to damage for my first go into multirotors.
I should call my hexacopter the dji 550 clone , The Turtle, because it spends most of the time on its back upside down.
It`s hard to set up in a very small garden , about 6 - 8 feet square . 

[Gaza07]

Looking good 

[DarrenG]

Well the ArduPilot has arrived and very impressed with the Mission Planner interface. Now saving furiously for the motors and ESCs so I can progress with the build.  I have at least now identified the motors and ESCs that I want.

Also now have a 5A uBEC from Turnigy and and a low voltage alarm/battery checker dongle.

Only thing remaining now is to choose a Transmitter/Receiver. Torn between a cheap and cheerful Turnigy 9X or spending a lot more and getting a Hitec Aurora 9 or a Spektrum DX8.  Finances may well dictate which one I go for!

[peter_a]

I`m using my old 35mhz mode 1 Transmitter while waiting to afford a better 2.4 ghz ( Like you a Spektrum DX8 or maybe a Turnigy 9X )

But it is confusing the hell out of me switching from mode 2 , which all my cheap little helicopters are , back to mode 1 , which I haven`t used for over 10 years ?.

[DarrenG]

I take it that you can';t switch your old transmitter to Mode 2?

[peter_a]

wow , you may have a point their !!!.

I little more difficult than modern radios but possible , I will have to swap the springs around a weak one for the throttle , and a strong one for the pitch  , plus move the gripper .

[Tango21Delta]

Hi, I am also using a Q650 from Unmanned Tech, getting decent results with the build below;

AttoPilot 180A Current Sense Breakout Board
Turnigy 5017 620Kv Brushless Motor
30A Multi-Rotor ESC (SimonK RapidESC)
12x45 Propeller Set Carbon Fibre Reinforced
HiTec Aurora 9ch 2.4GHz TX with 9ch RX
Turnigy nano-tech lipo battery 5000mAh 4S 25C To 50 C Lipo Pack
Castle BEC 10amp max 25v max
ArduPilot Mega 2.5 running Arducopter 2.9.1 mounted on foam ear plugs
UBlox GPS
3DR 433 Telemetry via Mavlink 1.44
5.8Ghz Fat Shark Video TX to Attitude SD Goggles
RCTimer Brushless gimbal (alexmos controller) with Go Pro Hero 3 Black

Can send pics if it would be of any help or if you have any questions just shout.

[DarrenG]

Excellent news. Would love to see some pics, especially of how you laid out the ESCs etc

Also any custom tuning of APM?

[Tango21Delta]

Just added some pics of the Q650 in albums, I will see if I can dig out the 2.9.1a param file. Just about to update to 2.9.1b, going to loose the ear plugs and switch over to moon gel to mount the APM, just need to do some more baseline vibration checking in RAW to compare the two prior to changing over.

[DarrenG]

Looks great, I see you';ve added another platform, I had wondered where I';d fit the ESCs, too tight between the two floors.

Also see you ran the motor wires outside of the arms, any reason why you didn';t run them internally?

[Gaza07]

If you upload pictures to the forum gallery you can very easily display them in your posts by simply copying the smg id tag from the gallery picture  in to your post

[smg id=248  It should look like this but with a square bracket on the end like the front, I removed it to stop the picture showing 

[Tango21Delta]

Cheers Gaza, will do.

Darren,
I didn';t think there was enough clearance for the motor wires through the frame arm strengthener without chaffing the insulation of the wires so we routed them outside of the arms.
We fitted the plate to provide extra mounting space for the APM, RX, MinimOSD, GPS without going for a stack system, originally we did it in 1.5mm carbon fibre but it wasn';t good, changed it for 3mm Derelin as it also provides some mass directly below the APM which when combined with the foam ear plug mounts has significantly reduced vibes in the APM. It also serves to move the APM away from the power distribution board in the bottom of the body of the quad. It';s quite tight getting the lid on but seems to work ok. The quad has been in constant redesign for the last 6 months, build test fly, rebuild test fly, it is a good stable platform using the APM2.5 and stock PIDs, just waiting for some good weather now to test it with the RCTimer brushless gimball

Mark

[DarrenG]

I';m itching to get going with the build, Tiger motors will be here tomorrow but won';t be able to do anything until the ESCs and the 9XR & Frsky Tx/RX arrive from HK. No idea how long that will take.

[DarrenG]

The Tiger motors arrived this morning.  No issues routing the wires through the motor arms, the tube stiffeners at each end are smooth and the wiring fitted through with room to spare.

I';ve some propellors on route from Quadcopters and just had a dispatch notification from HobbyKing for the ESCs and the 9XR.

[Tango21Delta]

Good choice on the motors, glad the wires fitted inside the carbon tubes looks a lot neater than mine. However, I would be careful having such a tight bend in the routing of the motor wires around the motor mounts. I have had motor connections fail at that joint and with such a tight bend there will be quite a lot of stress on the solder even with the heatshrink.

[DarrenG]

I was ';blindly'; following the frame build guide. That';s a good point, I';m waiting on some thread lock and will change that to avoid any issues when I re-assemble, thanks.

[DarrenG]

Still finding the subject of batteries massively confusing!  Can I ask what battery you fly on your Q650 or what you';d suggest as a good starting point with 900Kv motors and 10 x 4.5 props?

[Tango21Delta]

We are using a 4s 5000mAh 25 - 50C Turnigy nano-tech lipo battery pack on our 650 quad which is running Turnigy 5017 620Kv brushless motors fitted with 12x45 carbon reinforced props. We are getting about 11 - 13 minutes off a single battery or 20 minutes of a twin pack. The extra weight of the twin pack has quite an effect on the flight characteristics making the quad quite sluggish as you would expect so we fly single 4s 5000mAh  unless the extra flight time is essential. We will be doing some testing using 10x45 carbon reinforced props so it will be interesting to see the differences between the two.

[DarrenG]

Ah thank you, I was looking at Turnigy 4S 4000mAh packs so will go with a 5000mAh one.

[Tango21Delta]

No worries, have you thought about voltage and current sensing? or how to provide a clean source of power to the APM?

[DarrenG]

Got a Turnigy 5A BEC for the power supply to the APM. Also have one of the battery monitor/alarms. Haven';t got anything to actively sense v&c but may go with an attopilot as I';d read bad things about the APM power module cable.

[Tango21Delta]

We went with the AttoPilot 180A Current Sense Breakout Board after hearing the same about the power module cable. It';s a bit of a game to solder up, we used deans connectors directly soldered to the Attopilot, it';s been solid and is easy to set up in the mission planner. As for the BEC went for a Castle creations 10amp max, 25v max reprogrammed using the Castle Link USB tool to 5.4V, again no issues. We also use a battery monitor/alarm for low volts, velcro';d to the battery strap set to alarm at 14.4v.

[DarrenG]

I';m sure this is a dumbass question but the more I Google, the more I get confused.

I can see how the Attopilot supplies current & voltage data to the APM but how is this data accessed?  Is it only available via the logs after a flight?  Would I need telemetry in order to see this data during the flight?

[Gaza07]

If you use the telemetry modules and a laptop with the planner you will see the info in the HUD prob works the same with the mobile apps to 

[DarrenG]

Ah OK, thanks Gaz. Telemetry will be for another day but would be useful to have voltage and current logged so will get an Attopilot ordered.

Champing at the bit here waiting on the HobbyKing order, that';ll be a few weeks still unfortunately

[Tango21Delta]

We use the 3DR 433MHz telemetry set hooked up to a laptop via USB for Air / Ground data transfer. RCtimer have a clone set for $38.99 with free post that';s worth a look, Kit-433 on their website. If you use the MinimOSD for FPV it will also display the current and voltage direct from the APM in the display independent of the 433 telemetry. As an aside I installed the new(ish) 2.9.1b firmware update today, prior to the update we mounted the APM on Moongel, I must say the vibe results weren';t as good as I had hoped so we reverted back to mounting it using foam ear plugs. Very impressed with the update the quad flew well in Stab mode on stock parameters and the loiter was absolutely rock solid.

[DarrenG]

The entire subject of battery sizing is giving me a migraine!  I';ve run my set-up through eCalc and, (assuming I';ve done it correctly!!) configured for Tiger Motor 2216';s and 10 x 4.5 props, and a 4000mAh 4S pack it says:
max. power over the limit of the motor. Please check the max. power limits defined by the manufacturer!

OK, understand that,  too much power, so I need bigger prop or smaller battery I think?

So for a 4000mAh 3S pack:
For minimal maneuverability you need Throttle of less than 80%


I understand that the more cells = higher voltage but don';t fully understand how they all interoperate, particularly the props.

If I change to 12 x 4.5 props and the 4000mAh 3S battery I get no warnings. I';ve already ordered the 10 x 4.5 props but they';re cheap so if I need to go to 12 x 4.5 that';s not an issue.

But I';d like to to try and get a handle on this whole area so I can buy the right batteries, but the further I read the more I';m confused.

I don';t seem to get any errors if I go for a 3300mAh 4S battery and 10 x 4.5 props or am I better ordering 12 x 4.5 props and the 4000mAH 3S battery?

Or have I got the wrong end of the stick completely??  I';ve added a screen grab of the data I';ve entered in eCalc below.

[peter_a]

I think it is the other way around !!!!
More cells smaller prop size , not bigger !!!

for 4 cells try 8x4.5

[DarrenG]

That';s what eCalc says. 3S with 12x4.5 or 4S with 10x4.5.

Just don';t know what the optimum config I need to be looking for is!