RC India

While the Airboat build is progressing albet slowly, I am now attempting to build a Rogallo wing based microlite plane. I have some ripstop nylon lying with me, so would be using that.
The carbon fire rods lying with me are 4mm dia and 75cm long. So the dimensions of the wing are dictated by the rod length.
The build begins with the wing.

Started by creating the top brace. Cut out a piece of ply and stiched the three carbon fibre rods as shown below

Next step was attaching the cross brace wich is another 4mm carbon fibre rod of 75cm length. Prepared two ply triangular supports and stiched one ply piece on each of the two outer rods. The cross piece was stiched to these two pieces. After ensuring that the two sides were symetrical, applied cyno to the joints. The wing frame stands completed.

Cut out the covering, but decided to wait till later before fixing it to the frame. So next would be building the fuselage.

Ie, the pilot. Because the pilot is the fuselage ;D

Y is covering  bit smaller than frame?

@rastsaurabh,
Y ???. You mean Why?

Its not.
The covering will be pulled in towards the outer arms of the frame.
Allowing it to balloon between the centre and side arms.
See pic in my prev post..

This is very different, very interesting. I'm captivated  ;)

Quite a challenge as I am building from my imagination. Started work on the trike, took a lot of thinking for desigining the two axis movement for the wing.

@Iyer - I am not going with the hang glider version as this would require building all the servos and electronics inside the doll pilot. So building a powered trike microlite.

Will update today's build by tonight or tomorrow night depending on the progress.

Interesting! Subscribed :)

Took some curtain railing and after drilling lightning holes, made a basic structure of the trike as shown below. Steering and elevator servo holes were cut off and two 9gm servos installed. Now it is time to design the control mechanism for elevator and aileron functions. Lets pray that I succeed in making one.

Interesting   :thumbsup: best of luck

Update: The trike frame was joined using epoxy. However, the joints were not strong enough and opened under pressure. So rebuilt the trike but this time used rivets/screws at the joints.
Made a small plywood box for fixing the aileron servo. Attached two aileron cranks that I had which would serve as a bushing for attaching the servo box to the pillars. This servo box has to move in conjuction with the elevator servo attached to one of the pillars.

More pictures of the aileron servo box

Next step was to build the arm which would move in tandem with the aileron servo. Cut out a T shaped piece from lite ply and after drilling a hole inserted a small piece of brass tubing to serve as a bushing.

Since the Rogallo wing will rest on this pivot attached support arms for the two axis. One arm was inclined at around 15degrees to give the initial incidence to the wing. I have attached this part using hot glue so that in case of need the incidence angle can be changed depending on the flight performance.

Great going sir , Are the frame joineries riveted ?
Can you please post a pic of the rivets used and the tool . would be a great help
Regards

The wing support brace was attached to the top of the servo box using a thin bolt. The brass bushing already inserted into the T shaped support allows this piece to rotate around this bolt. The aileron servo was attached to this arm.

I then did a trial mount of the wing frame on the central pivot. Attached a receiver and tested out the concept. A youtube video is attached. I fell the servos need to be upgraded to more powerful servos. Maybe in the next version of the trike.

http://youtu.be/Eq9FB6HbkoA

@docnayeem. A photo of the rivets and tool attached.

Nice build sir... I have one question.Where did you source the nylon from?

wow this is fascinating! :O
just a thought, what if you used 3 servos in a 120 deg configuration? like a helis swash? that should give you a little more strength too...

 Superb, Ashok Sir !

.....here's a pic of the rogallo kit I put together sometime back......fits together quite well.
the main joint is aluminium and two extreme ones are teflon, center nylon....and the mid-strut clamps are 1.5 Almn.....

....hope to finish after yours.

.....deleted :)

.......an umbrella when opened is taut vis-a-vis its frame.....in a rogallo wing, it needs to BALLOON....so, the fabric is a bit larger than the frame.....

@ashok baijal,
For the main pivot to be strong and slop free, use 2 pairs of ball bearings of 3mm i/d, to fit CF shafts.
Hobbysea.com has them (3x7x3 & 3x8x3). You will probably receive within 3 days.
And try reducing the throw.
ESC sent, Speedpost ref EI021593848IN.

@Iyer
This being a trial version will not attempt using bearings. Will try in the next version. Yes, the throws he d to be reduced.
Thanks for the ESC. Will return it once I get mine.

Progress as on 17-07-2015
1. Made front landing gear. Used a cycle spoke and after coiling it shaped it into a landing gear leg. Inserted a small piece of wood at the end of the leading trike leg to support the landing gear. Also inserted a small piece of brass tube to work as a bushing for the landing gear. Attached the landing gear to the steering servo.
2. Prepared two balsa fins for the rear tyres which were attached to two L shaped alumimum supports epoxied to the rear leg supports. Used two 3mm bolts as axles
3. Extended the elevator servo arm to reduce the elevator throw and reattached it to the elevator servo.
4. Changed the aileron servo from a 9gm HXT servo to a Futaba 3003 as the torque provided by the HXT servo was not enough to support the wing in the desired position.
5. Strengthened the wing frame by adding two more pieces of carbon tube as the trike being of aluminum is heavier than expected. Attached it using a triangular piece of lite ply and glued it with cyno.

More  ...

...looks neat Sir...

Thanks Bmbib. Just hope that it flies as well.

Sir, could you post a small drawing of how the wing moves up, down, left, right... I am a bit confused

The wing pivot is based on the principle of a two axis gymbal. The elevator axis is supported by the two trike pillars whereas the aileron axis is the inner box with the aileron servo. Just see the build pictures above and see how a two axis works.
There are many ways to build such a mechanism. You can also try out a pan and tilt servo setup used for fpv video. Just see how they work and the idea would be clear. I took my idea from a gymbal used for stabilisation.
Difficult for me to draw as the setup needs to be drawn in 3d to explain its working but once you try it out practically, you will find it to be quite simple. One axis setup needs to be inside the other axis so that they are independent of each other.

Then I will be better off using a one axis (elevator) control for the wing and one servo for rudder. That is effectively 3 channels.

or you could manage the pitch with throttle alone like a paraglider and roll axis with weight shift. i believe it is much easier.

i thought of doing similar thing but sold off my kite.

There are many alternate ways of making a flying model using a Rogallo wing right with a rudder and elevator.The trike I have designed is a true weight shift design as there are no ailerons or elevator on the wing. The trike is actually moved around the pivot which shifts the trike position relative to the wing and is actually shifting the cg. In a real trike the cg is shifted by the pilot by moving the trike around the pivot using a control bar. This action I have tried to mimic using the two servos.if this is successful, my next model will have a robotic pilot which will be moving the control bar. The design is in my mind but development depends on a successful flight of this model. I love to build scale models as near to the real thing rather than just flying objects. Just my personal  passion.

Exceptional  :thumbsup:  :goodjob:

Added the roll axis control (refraining from using the word "aileron") rods which will also second as struts for the wing. Next step would be covering the wing, adding the electronics and wait for a good day to go out to check its flyability.

For people who are confused by the words elevator and aileron used above, please treat them as pitch axis and roll axis respectively >:D

I have understood what to do thanks to your pics and description. :bow: :bow:

Wing covered and installed. Used tape for attaching the wing cover to the leading edge and the central spar. Attached the wing frame to the trike using cable ties.

Wow ... That's coming on great sir ... All the very best for the maiden

wonderful......what I did was I stiched the wing and sealed the ends with hotglue.

@Topalle
This is the beauty of this hobby that a model can be made in upteen ways and that is what sparks your imagination and creativity.
@Docnayeem.
Thanks

The real test now awaits. Will it fly?   :o Right now it is raining or when the sun comes out it is too windy, keeping my fingers crossed.

 :goodjob: i like the l.gear cover. {:)}

@ashok baijal
Perhaps a photo using a table fan to fill the wings, to show what it's really like...

As desired by Mr Iyer. Photo from rear and front o the wing inflated with a fan.

Will paddlestand fans in some marriage hall will simulate?

Any source of wind should do the job :thumbsup:

Ready for testing. My workshop is full so sharing the bed with me for last one week. >:D Waiting for a fovourable day with some calm winds and someone to hold the camera

The finished weight of the trike is pretty heavy for the wing size. Though I added an additional carbon spar to reinforce the wing, the weight of the trike is enough to turn the servo. As such decided to scrap the aluminum trike and will build another with alternate materials. The rework will take more time than the sweepstakes end date. As such, withdrawing this entry. Nevertheles,  this has been an interesting project. Will carry it further later.

Sir dates extended till 07th Sep. Will be sad not to see this in the finals. Try making it time permits by then. May be just replacing with a bigger canopy/wing should do the trick. All the Best Sir.

Col this anyway was an experimental build. I plan to make the final trike with carbon fibre rods after a little more experimentation with the servo layout. This project is not going to die but will take some time. Will keep updating the progress on the forum

All the best sir waiting patiently to see the flight hope she carries the weight well

The Rogallo wing is too interesting to forget about it. The wing can be mounted on different types of aircrafts. So while the trike build is kept in abeyance, located a suitable project on RCGroups for a pusher plane for a Rogallo wing. Since I already had built the wing, and is larger than used in the project on RCGroups, I rescaled the plans to suit the dimensions of my wing. So trying my hand on this build for the Sweepstakes. The resized plans were drawn today evening.

Started fuselage build by cutting a 45cm long piece from 12mm balsa and another piece of 26cm from 6mm balsa for the tail. The pieces are 25mm wide but taper towards the tail. The two pieces were joined at an incline so that the tail comes in the prop wash.

What happened to the trike you bought on the forum a few years ago?

@Iyer. I never bought a trike. Dont have one.

Made tail feathers using a mix of coro and biofoam The stabilisers were made from laminated (two pieces of 3mm coro) while the elevator and rudder were cut out of 6mm biofoam. Bothe were covered with orange tape to match the colour of the wing.Pinned hinges were used for the control surfaces.

The pylon was made of two pieces of 2mm lite ply and balsa. The top was inclined at 14degrees and crossbraces were attached for mounting the wing.

With the pylon and tail feathers attached,  the trike has taken shape.

Landing gear and profile pilot (before painting) completed today

This looks a featherweight compared to the previous one.
Will you try a smaller motor and smaller battery?
Let me know if you need a smaller motor, prop, esc, battery.

Btw, i remember calling you (3 or 4 years ago?) to enquire about the trike you were (in the process of) buying from someone on the forum. Perhaps a para sail? Couldn't locate in your posts. Maybe it never materialised. Or maybe it was someone else...

@Iyer
This is much lighter than the previous attempt. Aluminum is not the way to go.

The purchase of the trike off the forum did not materialise.

Trike rigged up and ready for maiden  ;D

Rigging the control rod for the elevator was complicated and had to use a bell crank.  Used carbon rods to keep the weight of the tail to the minimum.

The front wheel is also connected to the rudder servo for ground steering.

All in weight except battery is 490gms.

Ashok Sir . great work ...  another masterpiece ... When is the maiden

delicate craftsmanship

Thanks Dr Nayeem and Iwincar. Maiden soon and certainly before the sweepstakes end on 7th.

superb  {:)} !

Thanks bmblb. Would like you to be there for the maiden.

Never seen anything like this..When are you maidening

Maidened today. However the battery strap came lose at takeoff and battery slipped out, disturbing the CG. The trike made an emergency landing. Notice the battery dangling below the trike. Enjoy the maiden.
More flight videos later.

https://www.youtube.com/watch?v=hOz3r_aJGWc&feature=player_detailpage

Wonderful Sir. Loved the flight. Inspired to make one too.

Looks good in the sky...Ashok what time you go to hoskote? Never seen you though..

@Sundram. Yes Col, it was an interesting experience building a trike. Need to do more flights to understand the flight characteristics of a Rogallo wing. The target is to build a weight shift trike. You should also try to make one and share your experience.

@foamybuider. Though I wish I could be a regular flyer at Hoskote, but personal issues at home keep me tied up. For past so many years I am keeping my models ready for a sunny patch in my post retirement phase. >:(

WANTED I need a few old motors for their bearings and shaft for making the swing mechanism for the weight shift  trike. Anyone willing to part off with old burnt motors?

Fantastic Ashok-ji  :salute: :salute:

You are the master aeromodeller  :hatsoff:

Thanks Sanjay ji. Just following in your footsteps.

Unable to go to the flying field for more flights. However the trike has been sitting on my dining table just to remind me to go. :'(

Wonderful sir :) Flies elegantly. Too bad the battery slipped off. Looking forward to more videos.

Thanks Vishal. Surely once I am able to slip out of my house to the flying field and someone is with me to film it. I want to try it out more as the maiden was a short one. It was getting late and we had to maiden the kfm6 flying wing also the same evening. Luckily that flew smoothly.

....flies so nice ! congratulations !

I was eagerly waiting for this video and was looking under the 'electric planes' category instead of here !

 

Thanks bmblb.

 :goodjob: :)

 {:)} {:)} {:)} {:)} {:)} great build  :thumbsup:

Thats very nice sir. Will try making one soon.

Thanks Wingmanbunty , romanxdsouza. YesJana.f22 with your expertise in building models this would've quite easy.

https://youtu.be/ye7_OM-nT-8

Very nice!  :thumbsup:

Sure drove the birds crazy  :giggle: