|Jan 07, 2012, 04:03 PM|
Quad Saucer - UFO - RCG R&D - read this before making a saucer !
I own a quad since spring 2011 and it fly nice
wanted to built a safer & strange look quad ...
with the exact same component layout... just want to add the donut...
made the body with white bead foam... lots of hole
to save weight... cover top & bottom with 3mm depron...
the thing endup at 1.9 kilo... my previous quad reach
1.4 with FPV gear+GOPRO and fly OK
--these 750kv 60g motor
--plush 30A esc
--multiwiicopter PARIS V3 board (work great !)
EDITED : Warthox & Erknie & other user find great answers ! thanks all
it fly, but prop tunnel need special attention and the airframe will slow down all maneuver
|Jan 07, 2012, 04:30 PM|
UK, Buckinghamshire, High Wycombe
Joined Feb 2007
in a windless environment it will fly just fine but ANY wind and you will find you have made a kite also a quad can told to some strange angles and yet still feel level to the eye when you build a frame like this every angle your quad flies at normally will look exaggerated due to the body and may put you off a bit with orientation
|Jan 07, 2012, 04:45 PM|
Joined Feb 2003
Looks good. Like Nemisis said, make sure you test fly in calm days.
Also make sure you round off the edges on the top of the inlets. Nice smooth and large radius.
|Jan 07, 2012, 04:59 PM|
thanks IWCoburg & all
troynh : amazing setup ... you are always many foot step ahead !
Believe me, if my toy fly good, look is the next step
Orientation : will go 100% fpv = solve...
OH, couldnt think of any better sound thrack !
i'v got there... amazing spot to fly !
n3m1s1s : agree with the wind=may cause lots of problem
dont worry with orientation...
SeismicCWave : thanks... EDIT you find a good answer= tunnel air flow
RESULT : see by yourself first attempt.. maiden
With all these empty foam holes, this thing
sounds lound ! amplifying all vibration & airflow ...
Pool noodle on the bottom are temporary...
if this thing fly OK , next step is top & bottom CONE
+nice legs+troynh LED kit !
|Jan 07, 2012, 05:22 PM|
biggest problem is the lack of YAW (rudder) authority
... ounce airborne... it always start to turn clock wise and
100% left rudder is not enough to get it back ? when i use
aggressive rudder... the saucer start to loose control on the roll+pitch
(lack of thrust on 2 motor)
-- all ESC are trimed/scaled together to match throttle span (throttle calibration done)
-- some motor has little alignement problem... has fix it ... still no good
-- the frame is pretty well balanced (scale check on all motor corner=ok)
-- need around 300W to hover... 400W peak recorded
-- easy to take off & hover at 50% throttle...
i suspect these problem
-- wind tunnel around propeller reduce the tork/roll effect thus yaw authority?
-- airframe too heavy ? may need lot more gain on the PID ?
-- PID settings : i'v changed the YAW rate from 0.51 to 1 with no success
any clue ?
|Jan 07, 2012, 05:23 PM|
United States, TX, San Antonio
Joined Feb 2007
Fun project It looks like your pitch and roll P's might be a bit low since it is appears it is having trouble wobbling with angle inputs. Try increasing them and see if it holds angles and level better.
An important suggestion is that I could hear your ESCs beep four times indicating you have the settings on lipo and not NiMh. You need to set the ESCs to NiMh, lowest voltage and no or soft cut-off. If you don't you will see that thee lipo setting will cause you some unintended flips. The lipo LVC will cause this when it cuts power to one or more of the ESCs as the power demand dips them into that cut-off level. Use a lipo balance plug alarm.
You can increase your yaw authority by increasing the dual rate of your yaw channel and increasing your yaw channel expo and or tilting your motors properly so the arms that increase speed are tiled to pull the model in that direction. It will be the same tilt on the same arm FB and RL, but opposite tilts on different arms. The info on this is in the Props section under --TIP 8: in the Quadrocopter and Tricopter Mega Link Index
Quadrocopter and Tricopter Mega Link Index
|Jan 07, 2012, 05:26 PM|
Joined Feb 2003
1) Please change the battery type on your speed controller to NiMH.
2) You are now maxing out your hardware. Rounding out the edge on the top lip of your propeller inlet hole will give you a little more efficiency. The sharp edge is creating a lot of airflow turbulence before the air is hitting the propeller.
3) Check the alignment of your motors. They should be perfectly vertical. You may have to shim some of them off center from vertical to get the yaw control back to neutral.
4) You are using some small propeller diameter compare to the total diameter of your machine so your yaw control is less sensitive. You may have to enlarge the propeller hole and use larger diameter propeller.
|Jan 07, 2012, 05:27 PM|
Just something that used to work on kk controllers and may help. Tilt the motors over a little (about 5 degrees), as you can use some of the thrust to counter torque as that was an old trick on the kk quads in the earlier days to improve yaw.
Blooming good effort though, love it.
|Jan 07, 2012, 06:51 PM|
Australia, QLD, Brisbane
Joined Nov 2011
Looks like a giant flying asprin! It's going to have problems with the wind. You might have to go to 3 blade props to get more low speed thrust.
|Jan 07, 2012, 07:27 PM|
Joined Nov 2009
You need to look at the surface area you are trying to yaw (twist) in the air. Looking at the ratio of total surface area/prop surface area you will see that your design is relatively high compared to a standard quad. Larger broad blade props, more of them or tri blades may give you more blade drag to move it quicker.
|Jan 07, 2012, 07:39 PM|
i made such a body last year. wasnt that fun to fly.
had to increase the p values by more than factor 3 to fly more or less stable.
had the same problem with yaw. the windtunnels were the problem. i 'rounded' the edges of the tunnels on top and bottom side and that helped.
i used my acro quad with keda 20-26m motors for that, normally pretty aggressive, but with the body it flew very slow. the body has an enormous air resistance.
i can upload a video of flying it if you are interested.
|Jan 07, 2012, 08:04 PM|
|Category||Thread||Thread Starter||Forum||Replies||Last Post|
|Question||Will this quad set-up fly good?||Dave8888||Multirotor Talk||13||Apr 17, 2012 11:23 AM|
|Discussion||Will this bird fly?||Nelatonin||Foamies (Scratchbuilt)||17||Jan 04, 2012 10:17 AM|
|Discussion||Will this scratchbuild fly?||-james-||Electric Plane Talk||10||Dec 28, 2011 10:42 PM|
|Sold||Alien flying saucer 4 channel Quad copter !!WOW!!||heli-parkflyer||Aircraft - Electric - Helis (FS/W)||0||Mar 29, 2009 01:50 PM|
|At 9000 feet Will it fly ???||wac||Micro Helis||6||Sep 16, 2005 06:59 AM|