Hi
My last fuselage broke so i am making a new one, since i do have 10props i do not fear crashing a lot, so vineet you can follow this.
Here it goes.
I am not confirming it will fly but atleast you can see it go and if all goes well it will fly.
After going through a lot of options i have decided,
I will go for a design similar to the image posted
Way to go!
Could you post the side-view of the wing? I wanted to see the airfoil shape...
Sure. This wing's airfoil is not atall pretty or dimensionally correct, but it works, and i have scarce depron to make another one.
I will be reusing the Wing, rudder and motormount.
Attached are the pictures.
i do intend to but a motor mount, i will buy one when ill go to bangalore on 3rd july, i want to buy one of those aeolian motormounts they have on rcbazaar
Step 2: Draw and Cut Out
Take measurements
Draw on foam
Cut out
Also mark the places for the servos to come.
Step 4: Make hinges
Step 5:Glue everything together
Step 6:Place the electronics
I made these dimensions in powerpoint, i dont have any of my usual softwares at home.
The top and bottom rectangles are the sidepanels
The elevator is fused in the base. That ways i have one parallel surface to worry about. If i had the depron, i would have made the wings, bottom and elevator on the same piece.
Vaibhav, I can't see the name of the Radio in the pic properly. Which Radio is it?
turborix FT06-A
Find CG of fuselage and place the wing 1/3 right over the cg
All done set to fly. Did three sorties
Sortie 1 - Prototype 1: (the first a/c) flew well, then a gust came and knocked it out of the sky, and broke.
Then i made model 2
Sortie 2 - Threw at 30% throttle so it stalled and crashed.
Sortie 3 - During my preliminary checks i noticed that the motor was a skew by a few angles, and not to forget my dreaded motor starting problem. ( im not sure if it is visible in the videos)
Threw the plane and it rolled over and crashed even though i was giving full input to roll, but after scrutinizing the video im guessing the controls were inverted :banghead: but im not really sure of that.
Propellor safe :)
Will rebuild the a/c but only after getting
Sortie 1:
http://www.youtube.com/watch?v=5jWhzASFmec
Sortie 2:
http://www.youtube.com/watch?v=CNPtre_SeJo
Sortie 3:
http://www.youtube.com/watch?v=6477TX9lU7w
Aeolian C2822-KV1200 brushless motor and a new motor mount (cage type) from rcbazaar
But that will not be before 18july because im going to bangalore from 3july to 17july.
And also learnt a few things
When in doubt, do not fly.
When in excitement, do not fly.
When in wind, do not fly.
Just did damage assessment.
Will fix the a/c and will try again.
Cant give up with just one crash.
Will make it fly
So the controls were actually inverted, im uploading the test video on youtube.
The problem was that the aircraft was rolling in the direction opposite to the stick.
Will test fly in the morning. ;D
http://www.youtube.com/watch?v=ayXeQLClIY0
All tests done.. Good to go, will try again.
I should have really tested this part.
Seeing how the first sortie nosedived and the elevators couldnt pull the a/c out of the dive i decided to add a safety feature.
and voila "spoiler" connected to the gyro switch on the Rx.
Cant test the design right now, because its too windy outside. Will fly as soon as the wind calms down.
It lives! haha it flies ;D
So the problem was that I had inverted the controls and the a/c rolled into the turn and crashed.
Then after rectifying the error by interchanging the servos on channel 1 and 2, i checked it again.
Then in the morning i made spoilers.
Just now returned from the sortie, which was cut short because of discharged tx, now charging it again, will fly and test the spoiler in the evening.
But it flies, so here you go vineet. One complete build log, with tests and crashes and reconstructions, but no prop breaks, awesome sturdy props by rcdhamaka.
Sortie 4 Powered upto 60%, gentle launch. Took controls, did sort of an "s", relieved that it flies and also worried about the tx battery, i landed the a/c.
http://www.youtube.com/watch?v=nvuNBTfRloY
This is how im thinking of testing the spoiler.
During the ground tests i realized that the elevators were responding better than the spoiler but i am guessing its because elevators are in line with the prop where as the spoilers are not.
When flying the spoiler will also be subjected to moving air and not just the prop wash.
So to test the working of the spoiler, i intend to
1. Take the a/c to about a height of 20ft
2. Cut throttle
3. Pitch down by 20 degrees
4. Switch on the spoilers, the a/c should pitch up.
5. Switch off the spoiler, turn on motor and land
gradually increase the pitch down angle till 70 or 80 degrees and test.
*numerical values are subject to change*
Tests delayed till Monday on account of a bad wall adapter for charger for LiPo
What happened to your adaptor? Mine blasted a few days ago. :banghead:
My adapter's light starts flickering after two mins and then it dies.
and its really windy in chennai! how is the weather on your side?
Weather's bad. Guess I'm gonna have to pause RC and play with robotics till the rainy season's over.
i got no time for robotics, i wanted to learn PID coding (just for fun) but now im running out of time so i'll not get into it, except learning PID.
PID is simple. There's even standard code for line-following, grid solving etc. I
standard code for what avr, pic?
Both!
come on seriously! i tried so much to find codes for a line follower based on pid, i knocked my brains out! i had something called an avr library but really couldnt figure how it works...
Yup, seriously!
With so many tutorials and forums, it's really tough to find exactly what you need. :banghead: We searched for like 3 months before we got anything promising. There's more stuff in AVR than in PIC concerning robotics.
You are currently in 5thsem, right? You must not have had a subject called 'Control systems' yet. It makes you realize how easily you can apply 'PID' and 'Fuzzy' in robotics.
I'm assuming you've tried the bang-bang algorithm (If you haven't, try that first).
Now, the industrial standard PID control mathematical formula (containing integrals and derivatives) can be modified into a simple one (additions and subtractions) for a LF Bot. Then all you need to do is tune the 3 constants till you get the correct set. And this can be easily done in AVR as well as PIC.
Oops! Looks like your thread's drifting away from RC! I guess we could carry this on in chatter zone. :)
Quote from: Swapnil on June 26, 2011, 07:58:26 AM
Yup, seriously!
With so many tutorials and forums, it's really tough to find exactly what you need. :banghead: We searched for like 3 months before we got anything promising. There's more stuff in AVR than in PIC concerning robotics.
You are currently in 5thsem, right? You must not have had a subject called 'Control systems' yet. It makes you realize how easily you can apply 'PID' and 'Fuzzy' in robotics.
I'm assuming you've tried the bang-bang algorithm (If you haven't, try that first).
Now, the industrial standard PID control mathematical formula (containing integrals and derivatives) can be modified into a simple one (additions and subtractions) for a LF Bot. Then all you need to do is tune the 3 constants till you get the correct set. And this can be easily done in AVR as well as PIC.
Oops! Looks like your thread's drifting away from RC! I guess we could carry this on in chatter zone. :)
I searched my whole 3rd sem i found lots of things but never a code on which i could reverse engineer and learn atleast.
I am now im 5th sem and im in mechanical there's no control system for us.
I have tried bang bang, i have tried to use a line sensor array and use it to give different speeds(PWM) for different values but no pid.
The biggest problem is i think that i know what needs no be done, but how exactly it is done eludes me.
Continuation on
http://www.rcindia.org/chatter-zone/pid/new/#new
Quote from: naatumach on June 26, 2011, 10:35:22 AM
...The biggest problem is i think that i know what needs to be done, but how exactly it is done eludes me.
Haha! Thats the problem with everyone man!
O.K, before I give anymore details here, I'd like to know how good you are with electronics.
Like, 'can you manufacture your own PCBs'... 'have you worked with SMD'...'have you memorised your AVR uC datasheet :)'...etc
This is important because... even a hobbyist can easily make a line-follower, but to make a really good one (i.e with PID) you need to know your stuff inside out. And it's good that you are in mech, 'cos you can properly fine-tune the required mechanical aspects like low inertia, low CG, proper traction, suspension (possibly!).
Which AVR are you using BTW?
Quote from: naatumach on June 23, 2011, 10:34:20 AM
... since i do have 10props i do not fear crashing a lot, so vineet you can follow this.
Which props are you using? And with which motor?
What's the progress with your plane? I'm gonna be sticking to deltas as they are simple and straightforward with less complex control surfaces.
Gonna try the 'Simple Delta' next.
http://www.rcgroups.com/forums/showthread.php?t=867083
And later the 'The Mugi Evo' perhaps.
http://www.mugi.co.uk/evo_intro.php
Nice designs. Looks nice, worth a try.
What i mind is that the wind plays a big spoil sport in this design. But its a wonderful design.
.
I use 8060 props, with the same motor from http://www.rcindia.org/self-designed-diy-and-college-projects/first-flight/msg68033/#msg68033
But i am going to switch to either emax CF 2508 or aeolian C2822 and buy X-Motor mounts
Regarding that avr
No i know none, i can only code thats all. I never got into it that much.
Hmm...without good knowledge of uC peripherals, it'll be hard. Try getting acquainted with a good one. But then, starting with micro-controllers can be as difficult and time consuming as with RC. Good Luck!
Then i think i'll pass. I am out of time for getting into uC because i only do rc to let off steam, i need to focus on college and gre now, baaki sab side mein.
After 'model-2' nose dived and broke. I did a nosejob on it, and left it. Then i went to b'lore. Now im back, i made the YF-22. But its too windy outside to fly, and i cannot sit idle so i took this nosejobbed-model2 for a sortie and the wind made it nosedive and the makeshift mount broke.
So i came back and made this modification.
The causes for trying out this design-
1. First model with the prop not touching the ground.
2. I never had much faith in my landing skills and structural integrity of landing gears. So i'll fashion some landing gears tomorrow, and learn to fly and land properly.
3. I can also use the ground for takeoff instead of a hand launch.
4. I tried to drain this battery and it lasted for 25minutes on full throttle on a ground run, i didnt assume it would run for so long. So i decided to make this and test my endurance.
And i love this type of motor mount.
Wow, that bird looks weirdly impressive!
I'm working on a similar design.
Waiting for your flight report...
Is that mount from RCD? It's currently out of stock there. Where else can I get one from?
I got it from RCB.
http://rcbazaar.com/category/89-motor-parts-mounts.aspx?pageindex=2
Oh, sorry, I meant to write RCB and not 'RCD'...typo...
Anyways, the 60 Rs. ones are out of stock there.
The one you have is for aeoilan motors, right? Will it fit a CF 2822?
Yes it can.
Attached are the photos.
You can also use at as a prop balancer
It's a bit pricey though...
Is it made of plastic or metal?
Also, what is the general shipping time of RCB?
They are metal. Very strong and sturdy, worth the purchase.
I didnt use the shipping option, i picked it up myself. I wanted to see the store. Nice store.
In the pic, there are holes for mounting a motor on both sides of the mount...or is it just me?
There are holes for mounting the motor on both the sides. unfortunately they dont line up with this motor, they do line up with the aeolian.
That's what I was asking when I said "Will it fit a CF 2822?".
I think I'll have to wait for them to restock those plastic ones...
But this ziptie thing is just as good. the motor doesnt budge or vibrate atall.
Hmm...could give it a try.
Quote from: naatumach on July 18, 2011, 03:32:32 PM
But this ziptie thing is just as good. the motor doesnt budge or vibrate atall.
Are you sure ? May be in other places, but definitely not as the only fastening points between the motor and the Mount!! These are plastic and not Kevlar. The ties would soon stretch just enough to give you enough viberations.
I would rather suggest you to use 'Stick' mount which are the best mount for you application, used by so many scratch builders:
http://www.rcdhamaka.com/index.php?main_page=product_info&cPath=56&products_id=410
The best part is that the bell of the motor, which is inside the inserted mount, would go right inside the hole in the plastic mount.
The zip ties are good. I have been using that in all my planes since two years, probably not on highrpm motors though.
Only issue with that is once its tied and glued if there is some problem with motor its a pain to remove the ties and to refit it you need to remove the wooden mount which is already glued to the foam.
Quote from: foamybuilder on July 18, 2011, 04:07:00 PM
The zip ties are good. I have been using that in all my planes since two years, probably not on highrpm motors though.
For metal to metal fastening instead of nut-bolt with lock-tite ? I do use them if one of the material is soft like Foam, Depron etc. Not on hard-hard surface as the only means to hang. May be as extra support/safety, but not in place of nut-bolt.
It can be used with between motor mount and plywood mount to replace nutbolt, again there is drawback as said earlier.
QuoteThese are plastic and not Kevlar.
Sir im sure our a/c will not be facing bullets anytime soon.
the stick mount looks alright, i still would go for X-Motor mount. Also its made of plastic not kevlar :P
These will be fastened by nuts and bolts which can easily come off under vibrations but a ziptie wont. This happened today only. And most of the metals used in RC are duralumin which deform when load is applied so we cant fasten very hard.
Intrigued by the Nylon-66 and Kevlar remark i decided to do some research.
[quote http://www.chemguide.co.uk/organicprops/amides/polyamides.html]
Kevlar is similar in structure to nylon-6,6 except that instead of the amide links joining chains of carbon atoms together, they join benzene rings.
[/quote]
and a little test of my own.
I made rings of '3.6x200' size zip ties and subjected them to 3 loads
10kg - Hung easily, did not break when shaken. Unnoticeable elongation
12.5kg - Hung easily, did break when shaken. Unnoticeable elongation
22.5kg - broke from the stopper. Noticeable elongation.
I would love to do a UTM test on it in college, let see if i could get the permission when college reopens.
@ujjwaana: Sir, no paronomasia intended.