Hi Everybody,
I would like to share with everyone what i found on the internet a while ago.
Is it possible to control an RC plane/heli without using these expensive radios?
To make our own DIY radio (using xBee!!). On radioclone.org it says that it is
some kind of a hack on an old radio, but i wanted to know that is it possible to
make our own radio - receiver/transmitter from scratch..
Just the communication part of the receiver and transmitter, like using Atmel microcontroller.
I have plans for the joystick (analog+digital).

You could either be a R/C enthusiast flying a Plane with a commercially available Tx/Rx or DIY trying to make one for a fellow flyer.

more than the RF part, its the Error correction, reliability, Resilience goes into a Tx.

Even if you make one using XBee, its gonna be costly at the end of the, even when compared to moderately priced commercial Radio.

Unless you are a true Electronics nerd, please spend more time with plane building and flying. 

Hello Sir,
Thanks for the quick reply. You got me. I am an electronics DIYer
and was interested in developing a radio from scratch. xBee was just an option.
I am not familiar with radio communications till now, so i will
be glad if i can get some light over this part, the microcontroller used, etc.
I really want to see my own home made radio flying my planes.
I have my plans for the joystick - the buttons and the analog stick!!
By the way, I am a final year Electronics & Communication Engg.

Hi Udawat,

xBee is an option, if you do not want to get your hands dirty with RF electronics. Further, xBee is an expensive solution compared to traditional RF electronics. I see that you are looking for an one-off build, so, I presume the excess cost may not be an issue. I'd say, build one for yourself and have fun!

-Ismail

Hi Ismail,
If i cannot go deeper than xBee, then i presume i will go
with it. But cost is an issue and i wanted to get even deeper
into RF. I am interested in RC planes and wanted it to be my
final year Major project. But since the communication part is
ready-made, i.e., simply buying the Radio, i was wondering
it won't be considered; as there is nothing i did in it except for
the plane model and putting together the prop, motor, servos.

There are quite a few circuits on the web that should get you started. If you are planning to do this for your final year project then I would advise you to go with xBee. That would be the easiest way of doing it and xBee is also the buzz word to attract attention.

Besides, nowadays, people do not appreciate original/scratch work - I bet if you develop your own RF transmitter/receiver with all the mathematical modelling etc, you would be winked at using an outdated technology... and your fellow mates that has bought some off-the-shelf hiend equipment for their project will be treated like geniuses!...

-Ismail

Thanks for the advice Ismail. I am starting to dig for RF Tx/Rx circuits
around the net and will post some useful results which can be of help...

xBee seems to be widely used in the diydrones.com crowd, for a variety of tasks.

Thanks for the reply Anwar. Their ArduPilot project is very cool.
Solely dedicated to the RC community.
Now some links related to xBee which i found on the internet:
1) - xBee Config Tutorial - nice video
2) http://diydrones.com/notes/ArduPilot - quite heavy for the pocket
3) http://www.ladyada.net/make/xbee/solder.html - nice site for custom xBee soldering
4) http://www.makingthings.com/documentation/tutorial/xbee-wireless-interface/overview - its a complete tutorial by a reputed site. See the bottom of page for Next buttons
5) digi.com - for their XCTU software

I got quite a bit of electronics stuff from sparkfun.com.  Here is a search listing for XBee there.

http://www.sparkfun.com/commerce/advanced_search_result.php?keywords=xbee&x=0&y=0&search_section=products

Tons of choices.

Hi, Anwar. Sparkfun have way too many choices for a beginner!
If someone wants to get into RC using xBees, then what sort
of xBee would be required - the basic or the Pros. Like there is
a difference of range in both these models - 300ft and 1 mile.
What do you recommend for a lightweight plane control?
And also - in the above video link - vimeo - xBee config, he uses
two arduinos with xBees; is the Arduino really required?

300 ft would be 100 mts, almost the distance b/w 2 goals of a football field, when you are anyway building y not the 1 mile?
All depends on your budget though. 

Hey Udwat

Why don't you use a Assan X8D hack module. This is a module which takes PPM signals  for upto 8 channels and transmits it in2.4gHz. They also have their own receivers which can be bought quite cheap... Sai has them. IF you are talking of joysticks, why not buy a simulator again from Sai and develop just the electronics for creating the PPM signals. The simulator would also give you a case to house everything in and you do not have the drudgery of developing the Tx and Rx parts yourself. The PPM part is where all the brain is... servo reversing, combining channels, trims, memory, etc. You can expand this project to where you want to go ... and this is quite do-able and practical.

I have used the X8D for converting my Futaba 6EX 40Mhz to 2.4ghz at the flick of a switch and it works quite fine. I have also done the same for Dr. Basu and he has also been using this quite effectively for the last 6 months or so. The range is also quite good... about 400m at ground level. Sai has also got one such system which he has been using quite regularily every week-end with no after effects. In fact with the 2.4ghz Assan we do not have to do a range check at all.

Any further info please do not hesitate to ask.


Saju

Hi Udwat,

Hope the following link may give you a lot of info
http://www.rcgroups.com/forums/showthread.php?t=994433

Regards,
Dileep

@Vinay: Thats a nice comparison. I myself am a football player
If the budget permits, i will buy the 1 mile module.

@saju: I am not that good at PPM circuitry. But will look at Sai
what he has to offer. Any info on PPM (basics) would be welcomed.
About the joystick, i am already prepared to make it. It will be using
tilt accelerometers (and hopefully gyro) from analog devices^TM
So that the control would be like real world.

@dileep: The link is very nice with lots of pics. I think this is what
saju has used to make his convertible 2.4 Ghz Assan Radio. (no offence!)

I had this !dea of the joystick/gamepad which i saw
implemented here:
http://prusadjs.cz/2009/07/iphone-controlled-rc-car-updated/

I had the idea before watching this video 

nice link man..

http://antibore.wordpress.com/2010/08/27/making-of-xbee-pro-868-based-rc-controller/

Also, see this :

"
An RC control system is not just transmission (which the XBee seems to take care of), but it also needs a "brain" that can translate stick positions, do mixing, signal modulation, sending PWM signals to servos etc on the receiver end etc (depending on what features you plan to implement).  The arduinos can play that role.  At least, this is my understanding, standing on the fringes !

Thanks Anwar, the video was really great. It seems like
2 xBees with its Explorer USB kit and an Arduino would
be required for this project.
Can you compare my following options: (range Vs cost - what should be given more
                                                       weightage? Remember its for plane, not car)
1.) XBee Pro 60mW Wire Antenna - http://www.sparkfun.com/commerce/product_info.php?products_id=8742
2.) XBee 2mW Series 2.5 RPSMA - http://www.sparkfun.com/commerce/product_info.php?products_id=8692
3.) XBee 2mW Series 2.5 Wire Antenna - http://www.sparkfun.com/commerce/product_info.php?products_id=8695
One more thing, Is there a need for second Arduino on the plane itself (receiver)?

One can buy the stuff from Indian sellers and have the feel of price.

www.feemo.in
http://www.rhydolabz.com
www.bhasha.co.cc

Thank you very much Mr. Singh. I really wanted to see
those sparkfun figures in Rs (shipping only costs $30)

Hi Udawat,
Please find below a link for RC Radio DIY, hacks n mods
http://www.lynxmotion.net/viewforum.php?f=21

This is the ultimate resource for making a DIY RC Radio.
Thank you very much...

Also have a look at http://home.nordnet.fr/~fthobois/anglais/engl-index.htm   (100% scratch built TX and RX)

This link has been posted by someone previously in this forum