AttoPilot Plane #2: RiteWing 65" UAV/FPV

[mhaun5]

Howdy.

I am adding to my arsenal. I have decided to build another AttoPilot autonomous plane, without scrapping my previous. By the end of the week, I should have two - three birds flying. Reason I say "two-three" is because I am actually building two wings.

The main reason for me to start building another has nothing to do with the performance or operations of my TwinStar 2. Rather, It is just so dang cramped in there that it is a royal pain in the ass to remove the Data Modem battery. Enough to give me an excuse to build Autonomous plan #2 / 3. :)

This airplane is based on Chris Klick's airplanes. He and I have been working together and he has cut me a custom airfoil to support the weight and flying characteristics I am looking for in a Delta based wing.

In addition, Dean has made me a custom AttoPilot 1.8 unit with side pin headers, which makes it much easier for profile based equipment fitting. This will work perfrect in the flying wing, as the thickest part of the wing is just 2".

I am still finalizing the details for all the components, but I have it locked down pretty good. Here is the shopping list:

(2) RiteWing custom 58" or 65" wings (different center sections I can use)
(1) AttoPilot 1.8 (side profile version) + assorted equipment)
(1) R5114 DPS Futaba 72MHz receiver (14 channel))
(1) Canon SD1100IS with CHDK framework (yep, purchased another one!))
(1) Pandora Pan / Tilt system with HS-81 + HS-65HB servos)
(1) DPC-480A Camera)
(1) 180o Servo Stretcher)
(1) 2.4GHz Lawmate 1W A/V Transmitter)
(2) Tanic Packs LP-4250-4S (4250 mAh / 385 grams))
(1) 9XTend OEM RF Modem)
(1) Scorpion SII-3020-1110)
(1) L-Style Motor Mount)
(1) ??? 70A ish ESC (still trying to decide on this one)

More to come...
Mike

[mhaun5]

Here are the pictures of the wings just laying against each other (non-assembled):

http://static.rcgroups.com/forums/attachments/1/8/3/2/4/a2428916-17-P1010021.jpg

http://static.rcgroups.com/forums/attachments/1/8/3/2/4/a2428917-242-P1010022.jpg

http://static.rcgroups.com/forums/attachments/1/8/3/2/4/a2428918-211-P1010023.jpg

http://static.rcgroups.com/forums/attachments/1/8/3/2/4/a2428919-180-P1010024.jpg

Last night I have been doing quite a bit of thinking for the drivetrain for this wing. I wanted something that would be pretty peppy, but still give me some decent air time. I think I ran through more than 500 different combinations in MotoCalc before I was pretty happy with a motor / battery / prop combination. I am still reviewing before I buy though.

More to come...
Mike

[mhaun5]

As mentioned before, I have run numerous motor, battery, prop, and gear ratios through MotoCalc. My goals have changed quite a bit as I have been playing with the numbers.

Originally, I wanted nothing but Super-Long flight times. Then, I some-what fell into the "RiteWing" speed culture and found a mix between the two. Ultimately, here is what my stipulations were:

- Be able to cruise at level flight (lift = plane weight) for 50+ minutes
- Be able to go full throttle and fly at 60 MPH +
- Be able to have a lower stall speed (~20 MPH)
- Be able to carry a full-sized Camera, Pan/Tilt & Camera, A/V TX, Modem, and various other gear.

This is what I came out with:

Motor: Scorpion SII-3020-1110; 1110rpm/V; 2.08A no-load; 0.016 Ohms.
Battery: TanicPacks LP-4250 4S (18C); 4 series x 2 parallel cells; 4250mAh @ 3.7V; 0.005 Ohms/cell.
Speed Control: Scorpion Commander 70A; 0.0013 Ohms; High rate.
Drive System: APC 9" Propellers; 9x5 to 9x6 (Pconst=1.11; Tconst=1) direct drive.
Airframe: RiteWing 65"; 640sq.in; 74.7oz RTF; 16.8oz/sq.ft;
Conditions: 1075ft above Sea Level, 29.72inHg, 65°F

Static:

Cells = 4S2P
Gear Ratio = 1.00
Diam (in) = 9.0
Pitch (in) = 6.0
Weight (oz) = 74.7
Batt Amps = 41.7
Motor Amps = 41.7
Motor Volts = 14.3
Input (W) = 598.0
InPLd (W/lb) = 128.1
Loss (W) = 65.1
MGbOut (W) = 532.9
OutPLd (W/lb) = 114.2
MotGb Ef(%) = 89.1
Shaft Ef(%) = 86.3
Prop RPM = 14917
Thrust (oz) = 64.7
PSpd (mph) = 84.8
RofC (fpm) = 1676
Time (m:s) = 12:13

Ultimately, at full throttle I am able to fly at 66 MPH for 18 minutes and 4 seconds. If I scale it back to about 38 MPH, I am then able to fly at 79 minutes, 44 seconds.

Attached are two in-flight calculations from MotoCalc at 100% throttle and 57% throttle.

More to come...
Mike

[mhaun5]

Late last night I started to design the cargo bay of the Wing. I decided I would just try to cut out a large center section, and then mount all the pieces inside. What I am finding out is that even with a 15" center section, I am running out of space!

I have been using the silly eMachineShop application to kind-of CAD out the design and layout. All of the items in the attached pictures are to pure scale; minus the actual AirFoil itself. I couldn't figure out how to input Coordinates to create the foil design.

At the moment, I am just moving things around, trying to get an idea. Please feel free to chime in and make any suggestions!

A few notes:
- The X/Y Sensor won't go in the bay, but rather on the surface in that spot.
- The GPS unit won't go in the bay, but rather on the surface in that general spot.

Oh, and please no attacks on my attempts for "CAD"; eMachineShop is like an upgraded version of Microsoft Paint - and I have no CAD skills. :)

Thanks,
Mike

[mhaun5]

Here is a picture of the custom side profile AttoPilot 1.8. Nice and light too!

Thanks,
Mike

[Gary Evans]

I have used E-Machine Shop to make some CNC aluminum parts and while it is fairly easy to use it doesn't accommodate compound curves unless they have recently updated the programming. Unless your going to have them CNC you a part the program drafting may be more trouble than it’s worth.
I think I would just try positioning components on the wing surface to determine what positioning is needed to achieve the CG and go from there.
I will be interested to see how the airfoil works out. I fly FPV and keep thinking about a wing but what available off the shelf isn't very well suited to the required weight and my lower desired speed.

[CenTexFlyer]

You really don't need that much motor or battery to get the numbers you want. It'll lighten the load to boot. Our Spectra flying wings come in just a shade over 4 lbs in glass and carbon at 48" span. You might check with Dean on the numbers he's getting with his, but they are similar to what you are looking for.

Gene

[CenTexFlyer]

Oh and a P.S.

You'll probably want to move your batts forward of their current position....

Gene

[dmgoedde]

You really don't need that much motor or battery to get the numbers you want. It'll lighten the load to boot. Our Spectra flying wings come in just a shade over 4 lbs in glass and carbon at 48" span. You might check with Dean on the numbers he's getting with his, but they are similar to what you are looking for.

GeneHmmm, my Spectra flying weight is only 3.3 Lbs, of course mine only has carbon/Kevlar on the LE and not everywhere. It cruises at 60 km/h on 50 Watts. The Spectra is very happy at only 60 km/h and now thanks to the latest Atto firmware, there is no worry about ground penetration in high wind situations; Atto won't let ground speed drop < 15 km/h no matter if the airspeed is already satisfied. Full throttle in level flight with the Axi Gold 2814/12 and APC 9x4.5 prop on 3s LiPo is no speed demon at 100 km/h, but has almost vertical performance. Max airspeed in a dive was 138 km/h (85 mph). Overall, it is a good balance of efficiency and reasonable speed with proven performance in 25-40 mph winds. It's not the Ritewing 160 mph speed craze.

[tekrunner]

Wow, an hour or more on a flying wing? Gonna need a bigger garbage for my motor gliders.

BTW, you worried about clearance for your pan & tilt so it doesn't hit the ground on landing? You gonna use skids or something?

[klique]

Hi Mike I think your cad drawing are great ,I agree with Centex your bats will probably need to move more forward.
I think your plan to leave the center section fully open to move the gear around will be great.


Once it is built and ballanced you will be able to do some comparment seperators with coroplast or somthing along those lines.

FYI guys I will be making these in differant sizes,50 through 100'' or so.

Chris
Ritewingrc.com

[CenTexFlyer]

Hmmm, my Spectra flying weight is only 3.3 Lbs

I guess I should have said that "shade over 4 lbs" includes a Lumix and full video suite (2 more cams, video MUX, and video battery). You have our standard build, the full carbon bird is a bit heavier. The full frangible wing is much lighter at around 2 lbs, and with the same motor setup is pretty potent!

So Mike, if you're going with a standard covering you should come in pretty light yourself.

Gene

[Gary Mortimer]

What do you guys cover those things with good old tape that sags in UV or something else??

G

[tekrunner]

What do you guys cover those things with good old tape that sags in UV or something else??

G


Good question. Something smooth and glossy would be nice.

[klique]

I Think Mike is going to use the Ritewing Method on the build dvd,it also can be found here.
http://www.rcgroups.com/forums/showthread.php?t=684818&highlight=ritewing

This takes it from a gooey tapie mess and turns into a nice long lasting durable super rigid airframe that doesnt chage its shape in heat .

Ck



What do you guys cover those things with good ol tape that sags in UV or something else??

G

[rbeall]

Mine's in the mail and I will be putting my homegrown autopilot on board. I'm gonna uses the 1220 scorpion with an Pheonix 80 on 3 cells but everything else about the same. I'm gonna be lighter because I'm just flying the AP but yeah maybe photo stuff later.

-Ryan

[airmcn_3]

Very cool build.

[mhaun5]

Quick project update:

I purchased the rest of the gear to get these two planes flying. I just dumped a decent amount of cash on all the pieces that will make this thing fly:

(2x) Scorpion SII-1110 Motors
(2x) APC 9x6E Propellers
(2x) 45mm Aluminum Spinners (not sure on these, but I purchased them anyway)
(2x) L-Style motor mounts
(1x) Scorpion Bearing lubrication kit
(1x) 2.4GHz Patch Antenna (Circular 8dBi)
(1x) DPC-480A OSD Camera
(1x) Pandora Pan/Tilt Kit
(1x) Pandora Tilt Plate kit for OSD Camera
(1x) Hitec HS-65 Servo
(1x) Hyperion Atlas Digital Micro servo
(1x) Hyperion Servo Programmer
(1x) 900MHz Antenna
(10x) Toroid Ferrite Cores
(1x) SMA Jack to RP-SMA Adapter
(2x) Park Flyer Plastic Air Cooling Scoops sheets
(4x) Futaba S9452 Digital High Speed/Torque Servo
(2x) LightFlightRC 70 AMP ESC
(2x) LightFlightRC 3 AMP BEC
(1x) Canon SD1100IS Camera
(1x) Transcend 4 GB SDHC memory card
(2x) Tanic Packs 4250 mAh 4S Lipos
(1x) Tanic Packs 2150 mAh 3S Lipo

Getting closer! I have most of the gear. Everything else will be in on Friday.

Mike

[airmcn_3]

Quick project update:

I purchased the rest of the gear to get these two planes flying. I just dumped a decent amount of cash on all the pieces that will make this thing fly:

(2x) Scorpion SII-1110 Motors
(2x) APC 9x6E Propellers
(2x) 45mm Aluminum Spinners (not sure on these, but I purchased them anyway)
(2x) L-Style motor mounts
(1x) Scorpion Bearing lubrication kit
(1x) 2.4GHz Patch Antenna (Circular 8dBi)
(1x) DPC-480A OSD Camera
(1x) Pandora Pan/Tilt Kit
(1x) Pandora Tilt Plate kit for OSD Camera
(1x) Hitec HS-65 Servo
(1x) Hyperion Atlas Digital Micro servo
(1x) Hyperion Servo Programmer
(1x) 900MHz Antenna
(10x) Toroid Ferrite Cores
(1x) SMA Jack to RP-SMA Adapter
(2x) Park Flyer Plastic Air Cooling Scoops sheets
(4x) Futaba S9452 Digital High Speed/Torque Servo
(2x) LightFlightRC 70 AMP ESC
(2x) LightFlightRC 3 AMP BEC
(1x) Canon SD1100IS Camera
(1x) Transcend 4 GB SDHC memory card
(2x) Tanic Packs 4250 mAh 4S Lipos
(1x) Tanic Packs 2150 mAh 3S Lipo

Getting closer! I have most of the gear. Everything else will be in on Friday.

Mike


Mike,

Nice! Thats a pretty mean list there. Looking forward to updates.

Chris

[tekrunner]

Quick project update:

I purchased the rest of the gear to get these two planes flying. I just dumped a decent amount of cash on all the pieces that will make this thing fly:

(2x) Scorpion SII-1110 Motors
(2x) APC 9x6E Propellers
(2x) 45mm Aluminum Spinners (not sure on these, but I purchased them anyway)
(2x) L-Style motor mounts
(1x) Scorpion Bearing lubrication kit
(1x) 2.4GHz Patch Antenna (Circular 8dBi)
(1x) DPC-480A OSD Camera
(1x) Pandora Pan/Tilt Kit
(1x) Pandora Tilt Plate kit for OSD Camera
(1x) Hitec HS-65 Servo
(1x) Hyperion Atlas Digital Micro servo
(1x) Hyperion Servo Programmer
(1x) 900MHz Antenna
(10x) Toroid Ferrite Cores
(1x) SMA Jack to RP-SMA Adapter
(2x) Park Flyer Plastic Air Cooling Scoops sheets
(4x) Futaba S9452 Digital High Speed/Torque Servo
(2x) LightFlightRC 70 AMP ESC
(2x) LightFlightRC 3 AMP BEC
(1x) Canon SD1100IS Camera
(1x) Transcend 4 GB SDHC memory card
(2x) Tanic Packs 4250 mAh 4S Lipos
(1x) Tanic Packs 2150 mAh 3S Lipo

Getting closer! I have most of the gear. Everything else will be in on Friday.

Mike


What kind of ferrite cores are you using? There's alot of options out there. I've ruined a number of good servos splitting and twisting the wire, intend to just wrap that servo wire in toroid next time.

Thanks

[mhaun5]

What kind of ferrite cores are you using? There's alot of options out there. I've ruined a number of good servos splitting and twisting the wire, intend to just wrap that servo wire in toroid next time.

Thanks

I am using the ones available from DPCAV.com. Here is the spec sheet on it:

http://www.dpcav.com/data_sheets/toroid1.pdf

Thanks,
Mike

[mhaun5]

Sorry I haven't had a chance to update the thread. Other things in life has had me busy.

Anyhow, I have done a few things to the wing and the overall build:

1) I built the Pandora pan & tilt unit with the DPC 480A OSD Camera
2) I glued in the upper and lower wing spars
3) I glued together the main wing together

Attached are some pictures.

More to come later.

Thanks,
Mike

[CenTexFlyer]

Dude.... I'm tellin' ya... move those batts forward are you're gonna have some real CG problems. Just a friendly suggestion :)

[mhaun5]

Dude.... I'm tellin' ya... move those batts forward are you're gonna have some real CG problems. Just a friendly suggestion :)

No doubt!

I need some help on layout here. I am trying to get a good idea of how to lay all of the equipment out. Here is how I set it out on the plane. What I did was move the two transmitters out on the wings. I was hoping to do this to help with RFI and space.

In regards to the Pandora pan & tilt, the servo will come into the bay. I just have it sitting in the rough area.

Thoughts before I draw / cut?

Thanks,
Mike

[CenTexFlyer]

It does look significantly closer to what might be required to get a proper CG, but here's my concern. We are using a similar sweep angle on our wings, and a double pack is still required ahead of the apex of the wings (the nose if you extend the wing lines). With the blunt nose configuration that you have, you'll need to keep your tips and elevons extremely light to be on for proper CG by the time you get a motor, adapter, prop, mount, etc. installed. I'd suggest some test glides to confirm CG, but experience tells me you could be putting in a lot of work on something that may not fly really well.

A secondary route could be to rotate your batteries 90* and mount your motor as a tractor, this may give you more latitude to work with on establishing the best CG.

Gene

[Gary Evans]

Having never designed a flying wing before will not deter me from offering free advice so take it for what it's worth.
Obviously the positioning of heavy components is critical to achieving the correct CG and if an early guess proves wrong fixing it later could prove to be problematic. I'm assuming, perhaps incorrectly, that at least the approximate CG is known.
If that is correct wouldn't it make sense to have ALL of the associated pieces temporarily in place first and then position components to achieve balance. Even if some of the lessor weight contributing parts cannot be ginned up in advance for this purpose the more complete the wing the less guesstimating required.

[Gary Mortimer]

Did this build go black?

[rbeall]

I still have mine going but don't plan on finishing it anytime soon. I'm currently in naval flight training and its killing my extra fun time.

The first one I built for the academy didn't fly because I couldn't get it airborne from the hand launch. I had to leave it at school. I probably could have gotten it airborne but the second one is still collecting dust about 30% done. Just rather write navigation software and fly it in an ARF than waist a bunch of time building a wing....very time consuming....

-Ryan

[Tom Harper]

I checked the original thread on 'Flying Wings' and there have been no recent posts. Looks like a project that shone brightly but briefly.

I hope it gets revived.