RC India

RC Models => Multirotors => Topic started by: satyagupta on March 15, 2012, 08:44:39 AM



Title: Need help with QuadCopter
Post by: satyagupta on March 15, 2012, 08:44:39 AM
Hey Guys i am building a quad copter,

I have a Hextronik 24gram 1300kv motor which generates around 432g of thrust.

And my whole copter(including batt and everything) i don't know how but i guess is going to be around 900g to 1000g. I have used normal aluminium rods for the arms and 5mm ply x 3 for the base. (pictures attached)

Now i am confused that whether i selected right motor or not?? do i have to buy a new motor for more thrust or these motors will bail me out??

One more thing, the mounts which are at the base of motors do they have standard sizes? or they differ??


Title: Re: Need help with QuadCopter
Post by: xxkrishxx on March 15, 2012, 08:57:48 AM
Correct me if i'm wrong
4x432=1728gm,so i think it'll do..


Title: Re: Need help with QuadCopter
Post by: satyagupta on March 15, 2012, 09:00:07 AM
hmm well how do you determine how much trust do you need for a copter?? Depending on its weight?


Title: Re: Need help with QuadCopter
Post by: Swapnil on March 15, 2012, 11:43:33 AM
Well, the thrust should be at least equal to the weight of the copter, shouldn't it?
I guess 1.5 to 2 should be enough thrust to weight ratio.


Title: Re: Need help with QuadCopter
Post by: satyagupta on March 15, 2012, 11:46:20 AM
Don't know yaar hence asking :D

So you mean thrust/weight should be 1.5 to 2 right?


Title: Re: Need help with QuadCopter
Post by: Swapnil on March 15, 2012, 11:51:37 AM
No. Thrust should be more than weight i.e

thrust/weight = 1 to 2

Actually 1.5 should be enough unless you are planning to attach a heavy camera or stabilization system later on.


Title: Re: Need help with QuadCopter
Post by: satyagupta on March 15, 2012, 11:53:13 AM
Thanks swapnil :) and for 4 rotors i would need 2 CW and 2 CCW props right?


Title: Re: Need help with QuadCopter
Post by: Swapnil on March 15, 2012, 11:59:07 AM
Yup! Actually, I've got a quad setup too and will start building in June. The motors I have give 900g thrust each and my AUW won't be more than 1500g!

Which control board do you have?


Title: Re: Need help with QuadCopter
Post by: satyagupta on March 15, 2012, 12:00:26 PM
I am building my own. Arduino based, got a tutorial google for AeroQuad


Title: Re: Need help with QuadCopter
Post by: Dharmik on March 15, 2012, 12:01:56 PM
Please note your AUW(All Up Weight) depends on it. For example one motor generates 500grams of thrust with 9x5 props so 4 motors will generate 4x500= 2000grams. If your AUW is 1000grams your quad will left surface at around 50% of throttle.


Title: Re: Need help with QuadCopter
Post by: satyagupta on March 15, 2012, 12:04:05 PM
@dharmik thanks for the valuable information

now i think i have made a mistake..
I have this motor:
http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=2069


with this ESC:
http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=6457

Right choice or wrong??? :(


Title: Re: Need help with QuadCopter
Post by: Swapnil on March 15, 2012, 12:06:15 PM
I am building my own. Arduino based, got a tutorial google for AeroQuad

And which arduino board and shields are you using?


Title: Re: Need help with QuadCopter
Post by: satyagupta on March 15, 2012, 12:07:10 PM
Arduino UNO and Arduino Protosheild along with

Gyro and accelro (3 axis both)


Title: Re: Need help with QuadCopter
Post by: satyagupta on March 15, 2012, 12:11:21 PM
So the motor that i have has max current rating of 7.5 and ESC i have is 18A is there a problem?? Will i burn motors down? :( crap crap crap


Title: Re: Need help with QuadCopter
Post by: Dharmik on March 15, 2012, 12:14:27 PM
Ok i read it, your motor draws max 7.5 Amp with 8x4 props. Technically i read ESC should be around 12-15Amp. Formula i read somewhere was
max amp draws by motor x 1.5 = ESC Amp rating
your ESC is bit overpower but it will work(incase you need to attach 9x5 props). My motor's max amp is 6-12A and i am using 20A ESC and it works fine without any problem.


Title: Re: Need help with QuadCopter
Post by: satyagupta on March 15, 2012, 12:17:55 PM
Thank god i have 9x5 props phewwwwwwwww... Now the props that i have are CW ones i think i can use them as CCW well. What do you think about this?


Title: Re: Need help with QuadCopter
Post by: Swapnil on March 15, 2012, 12:19:00 PM
Arduino UNO and Arduino Protosheild along with
Gyro and accelro (3 axis both)

Cool! Where did you get them from? Could you give me the links of the above items?

The motor and ESC combo seems O.K. According to one user, it gives a max. thrust of around 425g with a 9x4.7 prop on 3s LiPo. I guess that should be good enough.

How do you intend to use the CW as CCW?


Title: Re: Need help with QuadCopter
Post by: satyagupta on March 15, 2012, 12:25:34 PM
How do you intend to use the CW as CCW?

To be frank i dont have any idea yaar... but when i do i will let you know :D the 9x5 props that i have, couldn't similar looking CCW that i can use.

Btw the links

http://simplelabs.co.in/ For arduino and proto's (cheap and good)

http://tenettech.com/ for the rest of the stuffs :) (gyros and accelro)


There is one more but i am not able to recollect the name i will post as i remember it :)

Got it:

http://www.catsystems.in/


Title: Re: Need help with QuadCopter
Post by: Swapnil on March 15, 2012, 12:27:39 PM
Thanks for the links!

Why don't you just purchase a CW+CCW prop set? I think sai sir has some.


Title: Re: Need help with QuadCopter
Post by: satyagupta on March 15, 2012, 12:28:41 PM
Who?? where??? links? please i will buy right away....


Title: Re: Need help with QuadCopter
Post by: Swapnil on March 15, 2012, 12:29:57 PM
Just a moment...


Title: Re: Need help with QuadCopter
Post by: Dharmik on March 15, 2012, 12:31:15 PM
I would suggest you to go with 8x4 CW and CCW props which is suggested on site, they will produce 1600-1700grams of thrust. With 9x5 props your motor will get warm above 60% throttle. Try to reduce quad weight so you can achieve best performance. See if you have all CW props you have to mount two motors upside down and props need to run in opposite direction but it will affect efficiency as they meant for CW direction(check its aerofoil shape). Better go with CW and CCW.


Title: Re: Need help with QuadCopter
Post by: satyagupta on March 15, 2012, 12:34:24 PM
Dharmik i was thinking the same but not able to find a 8x4 props :( any seller?


Title: Re: Need help with QuadCopter
Post by: Dharmik on March 15, 2012, 12:38:09 PM
Check rcelctro.com, rchobbyaddict.com, rcbazaar.com, rcforall.co.in they all keep pair of such props as Swapnil said.


Title: Re: Need help with QuadCopter
Post by: Swapnil on March 15, 2012, 12:41:12 PM
Here you go!

http://rchobbyaddict.com/product_info.php?products_id=377&osCsid=5f1b34f02415234bb17cf65b7ca4beca

http://rcelectro.com/index.php?page=shop.product_details&flypage=flypage.pbv.v5.tpl&product_id=178&category_id=7&option=com_virtuemart&Itemid=7


Title: Re: Need help with QuadCopter
Post by: satyagupta on March 15, 2012, 12:42:20 PM
Swap bro the rchobbyaddict.com dont have stock for the props :(


Title: Re: Need help with QuadCopter
Post by: Dharmik on March 15, 2012, 12:44:31 PM
Yes and this one too
http://thehobbyshop.in/index.php?main_page=product_info&cPath=11&products_id=30


Title: Re: Need help with QuadCopter
Post by: satyagupta on March 15, 2012, 12:46:19 PM
THS is too costly... i guess rcelectro is good.. I also wanted heat shrinks bad they dont have heat shrinks :(


Title: Re: Need help with QuadCopter
Post by: satyagupta on March 15, 2012, 01:01:08 PM
RCeletro user registration disabled y?? :(


Title: Re: Need help with QuadCopter
Post by: Swapnil on March 15, 2012, 01:22:18 PM
Well, you can just call the owner (VK). I've always had awesome service and help from him.
I generally get the package from him within 2-3 days. I booked my order via sms this monday and got it on wednesday!


Title: Re: Need help with QuadCopter
Post by: satyagupta on March 15, 2012, 02:14:58 PM
Nice yaar.. But where is the contact number??


Title: Re: Need help with QuadCopter
Post by: satyagupta on March 15, 2012, 04:49:57 PM
Thank you guys Swap and Dharmik i bought CW and CCW props from rcelectro.com

you both deserve +1