Pollux FPV Racing Hex 10° Angled Motors

iwandi

Junior Member
I wanted to share the plans for my current build.

Its a Spider Hex for FPV. The special thing about it. It uses 10° forward angled motors. I relay liked the idea from shrediquettes GEMiNi to improve the top speed of the quad by slightly angeling the motors forward.
http://shrediquette.blogspot.de/2013/03/wind-tunnel-test-data.html

I have a Blackout and i relay admire the construction so i tried to combine both ideas. Also i wanted to have universal parts (no special left-right arms or mounts). For this i had to angle the arms in just the right way. And also have a wired pattern in the arms.

Here are all the plans:
- A bill of material is still missing. I need to write that. Also some parts are not yet fully planed out.

http://www.thingiverse.com/thing:282606

It uses 40mm spaces between the top and middle plate. This also to mount bigger 38mm FPV Cameras. I also put mounting holes for a KK board in the middle plate.

Today (17.04.2014) i orders the plates (carbon-posten.de) and the mounts (shapeways).

For electrons i am going to use:

FC : Acro Naze32
ESC : Some 12-15A with SimonK
Motors : T-Motor MN1806 2300KV
Propeller: GemFan 5x3 2 Blade
Receiver : D4R-II
Live Cam : Sony Super HAD CCD 600TVL 2.8mm lens
HD Camera : GoPro3 Silver
Video Transmitter : Immersion RC 600mw
Antenna : Immersion RC SpiroNet v2
LiPo : Turnigy nano-tech A-SPEC G2 1800mah 3S 65C

This is my first custom build so i am sure i made some error. Some aspects i still have to figure out.

Pollux_Assembled.PNG Pollux_Assembled_side.PNG Pollux_Assembled_top_angles.PNG MotorMount_bottom.PNG MotorMount_top.PNG Broom.PNG
 

engineer

Senior Member
I love the idea! I've been wondering about fixed/variable forward tilt motors on a multicopter for a while.

I think you might also want to add a landing gear in the front, just enough to level out the motors while parked... but... then you'd need to level out the flight controller too... so maybe not. But on the other hand... what will the flight controller do when it senses forward movement with no input? Will it pitch back? I can't wrap my brain around the hover at this time in the evening...
Keep us posted!
 

Tritium

Amateur Extra Class K5TWM
The HUGE "Kracken" by FoxTech uses motors that are tilted in by 5 degrees. This moves the turbulent air column from directly beneath the craft resulting in very stable descent and hover.

Thurmond
 

adamd

skunkworx hobbies
would this mean in a hover you're tilted back slightly? I have always hypothesized with this idea, great looking rig for it too!

if your looking for speed and efficiency check out cyber's cyberhex post on Thrust column efficiency. great read with a lot of good ideas already discussed.
 

engineer

Senior Member
I know this design is a "second-kind of cool" for you and that's really important in a hobby, but..
I agree with adammd about the thrust column. The 5" blades don't have a whole lot of disc area to start, and those large/flat plates will block a lot of air. In that article (wasn't the main point but), if you use a round cross section on your arms, it is still very simple and has much improved characteristics for reducing the thrust loss. Speedy is the goal?
 

adamd

skunkworx hobbies
with the thick flat plates under your current setup, you're looking at the booms taking up a little more than 17% of each rotating disk.
don't take this as a "it wont work blah blah blah" it will work fine but if you want max speed loose as much of the parasitic drag as possible!. other than that it looks sexy as hell! subscribed!
 

iwandi

Junior Member
@engineer
10° should be ok to start. On my blackout i usually start right away in a forward move.
The FC is in-line with the frame. I will set a angle offset in the Baseflight to adjust the hover angle.
After having the parts in my hand i agree the arms a lightly to wide.


@adamd
No the hover has the blades straight and the frame at a 10° angle. I id look at it. But my design is not as radical. It's a FPV Spider hex while only improving the forward speed by slightly tilting the motors.


The carbon frame parts came way quicker then expected. I assembled them and already noticed some errors i made. But overall it worked out relay good. As this is my second build after the ARF Blackout Mini-H, i feel relay got a well the parts work.

I assembled the frame with combined 30mm + 10mm standoffs and M4x10 + M4 Locknut (DIN 912). The M4 connection is all Steel and come's in at about 50g. So i ordered some Aluminum M4x10 + M4 Locknuts witch could come in about 25g.

Now i am waiting on the shapeways parts and the T-Motor MT1806 2300KV to become available to order.

Here are some pictures of the assembled frame.

IMG_20140419_172230.jpg IMG_20140419_172240.jpg IMG_20140419_172253.jpg IMG_20140419_172300.jpg IMG_20140419_172314.jpg IMG_20140419_172339.jpg
 

iwandi

Junior Member
carbon-posten.de. Thy have a cutting service if you contact them.
69,95 € incl. Tax. (19% Germany) and 4,90 € Shipping (Germany -> Germany)

Overall for the price great value. It has dull B Quality finish, but the stability is spot on. All the edges needed sanding but thats common with CF parts. Rigidity is spot on. Communication, production and delivery was exceptionally fast.

I updated the Thingiverse blueprints with a v2 LiveCameraMount and added a parts list.
 
Last edited:

iwandi

Junior Member
Shapeways Parts

My Shapeways parts arrived.

Thy fit relay nice. I test mounted a motor (From my Mini-H). And also tested mounting on to the frame. Only one issue, if the lock nuts are to stiff thy start to spin inside the mount. But threading them with a screw ounce and them using them works. The reduced tightening force should not be relevant.

Shapeways parts: 10g
Motor mount screws: 10g

Aluminum screws for the frame: 15g

I also replaced the steel screws in the frame with some nice color matching Aluminum screws. This saves up 30g.

Now i need to get my hands on some MN1806 2300kV

IMG_20140425_195626.jpg IMG_20140425_195637.jpg IMG_20140425_195654.jpg IMG_20140425_195718.jpg
 

iwandi

Junior Member
Finlay revived all the parts and was able to assemble.

The mounts worked out just as planed.

I had it flying already in the park and adjust some PID's. Tomorrow i am going to get the first in with FPV and post some videos.

IMG_20140517_175634.jpg IMG_20140517_175641.jpg IMG_20140517_175647.jpg IMG_20140517_175711.jpg IMG_20140517_175724.jpg IMG_20140517_175745.jpg IMG_20140517_175753.jpg IMG_20140517_175802.jpg
 

iwandi

Junior Member
I tried to get some nice footage in a open area. But as i arrived there one error after another kicked in. So i could not fly there and had to go home to fix things. But just before the sun set it managed to get some good footage in a close by park.

http://youtu.be/HVizB0mzKK8

The PID still need tweaking but the GoPro footage and Live footage is stable and with no jelly. For the next revision i need to reduce the surface area. There is a noticeable resistance to climbing.

Already crashed it twice and can same it has the same crash resistance as a Blackout.
 

engineer

Senior Member
Nice video! That park looks like a great practice location for racing.

Did you notice any increase in performance from the 10 deg angle?