A small DIY quad within everyone's budget

Started by satyagupta, May 05, 2013, 11:08:44 AM

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cheluvaraj

Revolutionary potential is only limited by our imagination

satyagupta

one stop for multirotor needs:
www.quadkopters.com

http://www.facebook.com/QuadKopters
https://www.youtube.com/user/QuadKopters
https://www.instagram.com/quadkopters

girishsarwal

I am not sure why should capacity be a problem. Capacity only specifies how much current (or rather energy) 'can' be drawn, not which is being drawn. On the flip side, this battery should provide more flying time for the quad, unless the motors heat up and stall. The voltage matters though but you're running 1S which is the quantum for LiPos.

Needless to say, the board seems toasted.
gs

arun.sreelakam

I second that... the mah won't matter at all.. you could have fried that board coz of some short circuit.
And satya may have think like more mah will increase flight time hence the board will heat up more and there chances of frying up...
???


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Turnigy i10|Flysky 9xb|Hoverfly quadcopter|Arduflyer apm 2.5 with gps|Pixhawk|Homemade micro night vapour|Homemade ornithopter(in progress)| Reptile Quad with Gopro Brushless gimbal | Naza v2| APM 2.6 with GPS | Micro quad self made | FrSky| v911 Helis | 1200mm Hexacopter with 5d gimbal | 1300mm x8 With Red Gimbal | 1000mm Octo|

cheluvaraj

Arun,

Definitely there was no short circuit.  :'(
Board and battery both has male and female plugs so there is no chance of short circuit.

I'm quite new to electronics & electricals. As mr. Girish said, was also under same impression that it might work with higher mah too... so went and connected the battery.

Cheluvaraj
Revolutionary potential is only limited by our imagination

satyagupta

I dont know, but initially my plan was to give 500mah with the kit (for more flight time) all suppliers said anything more than 400 mah will fry the board. Even in RCG there are couple of posts where users question the author about more mah and he has said same thing. :headscratch: :headscratch: :headscratch:
one stop for multirotor needs:
www.quadkopters.com

http://www.facebook.com/QuadKopters
https://www.youtube.com/user/QuadKopters
https://www.instagram.com/quadkopters

sundaram

I would second Satya on the damages of Higher mah.

Higher mah lipos has the capacity to deliver higher amperage without equivalent drop in voltage. Higher ampere delivered combined with higher voltage results in higher wattage delivery in comparison with a lower mah lipo setup. If the motor has the capacity to draw more amps then it will load the system and as a result either the ESC or the motor will breakdown.

This has happened with me when I was testing a EDF of 650 watts. when run with single lipo the system was running perfectly fine for many hours. when I was testing it in the test stand connected with many lipos in parallel board, so that I don't have to change lipo often, the same setup burned out the motor within a min of operation even though the Lipo was 3S in both case. Since the ESC was twice the required amperage complete load was on the motor.

However when the motor does not have the capacity to draw more amps (Higher impedance motor) then nothing will happen to the setup even though you increase the mah.

cheluvaraj

Mr. Satya,

Would like to suggest that you should put a note (not to use higher mah battery) for this kit.

Cheluvaraj
Revolutionary potential is only limited by our imagination

rastsaurabh

But in your case of instant spark and smoke the polarity of battery may be the culprit.

aniket210696

here's a build tip... if you have the weak motors, and want to make it light, make a 15cm cross with the bamboo sticks, make a platform with coro, mount the motors to the tips of the rods with blobs of hot glue, and use depron pieces to make any aesthetics on it....

tomorrow I'm entering this baby into a science exhibition... people get very excited to see something fly...  :P will post pics soon!  ;D

regards
aniket

Sent from a potato using a lamp
.

satyagupta

one stop for multirotor needs:
www.quadkopters.com

http://www.facebook.com/QuadKopters
https://www.youtube.com/user/QuadKopters
https://www.instagram.com/quadkopters

lastRites

Quote from: aniket210696 on August 05, 2013, 11:41:03 PM
mount the motors to the tips of the rods with blobs of hot glue,

Bad idea IMHO. The motors easily get hot enough to melt the hot glue.
It is the pervading law of all things organic and inorganic,
Of all things physical and metaphysical,
Of all things human and all things super-human,
Of all true manifestations of the head,
Of the heart, of the soul,
That the life is recognizable in its expression,
That form ever follows function. This is the law.

aniket210696

ya I was also doubting that, but after testing, I found the motor heat is not enough to melt the blobs so much that it drops the motor... the glue is thick and sticky enough to work...

Sent from a potato using a lamp
.

siddaniels

Just wanted to thank everybody on this thread. i had purchased the DIY kit from Quadkopters.com and built it in less than 3 Hrs ( using the RCG 18$ quad thread ) felt really happy with my self, but once i tried to fly it all my happiness drain away slowly with every crash. Caused by the various issues discussed in this thread. so i gave up on the first build and have started on "V2" which will hopefully be a much lighter frame thanks to all the info i have read here.

Thanks again.



Yusuf

Hey Satya Bhai this is a very nice kit ... Thanks a ton making it available.... Got my kit a few weeks ago Nicely Packed and ON TIME !
My Quad Mk1 and Mk2 had a few issues same as the ones discussed here ( SOLVED THEM USING THIS FOURM )
I am Going For My Quad Mk3 now with the 553 FC . 
And Yess Where can i get the Micro JST pins used on the v939 i need more of those connectors??? i couldn't find them on your site.

satyagupta

Dear Yusuf, thanks for the appreciation :) glad that you liked the kit.

Those micro jst connectors are not easily available, it was a nightmare for me to find few of those. I just got few 100 hence i have kept them to give along with the KIT. I am trying again to get same connectors to sell them separately :thumbsup:

PS. Guys where are build logs, images videos?
one stop for multirotor needs:
www.quadkopters.com

http://www.facebook.com/QuadKopters
https://www.youtube.com/user/QuadKopters
https://www.instagram.com/quadkopters

siddaniels

First and for most a big thank you to everyone here for all the info you have given. For an amateur RC hobbyist like me the information here is like the Holy Grail and you guys are the Illuminati.

Secondly I AM AN AMATEUR RC HOBBYIST... So I can and will be wrong. Please don't hold it against me and please correct me where I'm wrong. Also I'll have a lot of stupid questions, so bear with me please.

Thirdly this is my first attempt at a meaningful post... I'm trying my best. 

Back to topic...

Here are a few pictures of my DIY micro Quadcopter.



My first attempt which was a complete disaster. I had mounted the motors with cotton thread and then covered them with 5 min epoxy thinking that everything was alright. Well... everything looked alright anyway ( The motor looked like they were at a 90deg angle).  The quad would take off and then pitch seriously towards the rear even after my pitch corrections from the Tx.  So I would power down and land as I don't have a lot of space at home. After that it would refuse to leave the ground. The problem was a combination of mistakes...

The motors were not at a 90 Deg angle.

The center of gravity of the board was incorrect. ( A very big factor for stable flight. At least for me.)

The huge blobs of epoxy were adding to a lot of extra weight. 

The Tx Calibaration was incorrect on my HK T6A V2. i.e. End points, throttle curve. (Another  important factor for stable flight. I still haven't got it right. Hopefully my Grail will help...)



So I left the V 1 frame and from the info I read on this thread ( Am I calling it right? this is a thread right?) I tried my hand at a Version 2.



I decided to use a motor mount like - @Arun.Srelakam, @Sudhakar_yg, @xtreme_@machine, @sundaran, @shivela39, @satyagupta - the main man who made it possible, though all of you made it work, @VC, @Veloci and @bilal.  My apologies if I missed anybody out.

Here are the pics for the motor mount and basic frame for V 2. (Motor to Motor length 114mm)




I used a cross I had drawn on an A4 size sheet using a protractor ( thank you to @arun.srelakam ) to align the two length of bamboo sticks.

This was a 2 stage process. First I used Fevicol SH to join the two pieces of bamboo while constantly correcting the alignment on my A4 diagram
In the Second stage, once the fevicol had dried and I was sure of the alignment I dropped very little epoxy on the joint to seal the deal.

I followed a 4 stage motor mounting and securing process.

First, I burnt a hole in the sketch pen body that I was using with an old soldering iron and inserted the mounts on to the ends of the bamboo sticks. Then checked for alignment issues.

Second, I jammed the motors into the motor mount. Here I spent some time aligning the mount and the motor using an L shade diagram on paper. These paper diagram are very good for basic aligning of motors. Another good way to see if your motors are aligned is to use the same cross used for aligning the bamboo stick, turning your micro quad upside down and seeing if the motor shaft center point of all 4 motors sits exactly on the lines you have drawn. You could still be off the exact mark but this process helped me a lot in getting my micro quad flying.

Third, After I was 90% convinced about the motor alignment, I mixed up some epoxy and first glued the mount i.e. the sketch pen body, to the bamboo stick frame with the motor in it. Again constantly correcting alignment.

Fourth and final stage I added epoxy to the motor and motor mount joint. Again constantly checking alignment.
With the motor alignment things can go wrong without one knowing it so it's best to spend as much time on it as you are willing to give.






The V 939 FC mount needs some work.

But what I essentially did was use a packing foam block with Velcro stuck to it. I stuck small square pieces of Velcro on the FC board's mounting holes and used it to hold it in place with the other piece. While it looked very flimsy to me it seemed to give me decent results. But I would prefer a more solid mount. Maybe I'll use double sided tape instead of Velcro. Any suggestions ? (taking the FC off will be a little difficult with Double tape.)

I read this on the rcg 18$ quad thread.

The center of gravity plays a very important role in this V939 FC board. While larger quad FC boards like the KK board and the HK board ask you to mount the board on the same plane as the propellers, this V939 FC should be mounted on a lower plane as compared to the props. This setup has been a great help to me. It has removed the crazy, tweaky effect that I was facing earlier. I actually got FULL ON stable fight when i lowered the plane of the FC as compared to the props. Not that I don't have problems even now, which I will elaborate on later, I have still been able to fly the quad well for a considerably longer time than in version 1.




Now that everything was setup I went on to TX Calibration...

@VC sir – I assume you are using the HK T6A V2. If I am wrong pls ignore this question. If not... Have you been able to find a decent setting configuration for this quad FC board.

I reconfigured my TX, put it on ACRO mode. Reduced EP to 75% on all 4 ch. ( thank you @Ankit210696 & @Arun.Srelakam) but I still have a problem.
The quad only lifts off at 50% – 60% Throttle and at 100% throttle it stays up in the air for about 6 sec then it starts to drop down.  I tried stopping for a min (like @sundaram sir) and it does the same thing (lifts off at 50% – 60% Throttle and at 100% throttle it stays up in the air for about 3 sec then it starts to drop down) only after the second try the quad refuses  lift up. I think the problem is in the throttle config i.e. throttle curve ( as mentioned by @Bilal sir) or the frame is too heavy. I don't have a gram-o- meter but I have a cousin coming in with one soon, so I'll the weight of the quad.

Anybody using a HK T6A pls share the config settings...

Now that I have stable flight but not for more than 6 sec in the first try and about 3 sec on the second try, I would really appreciate your opinion on how to get it to stay in constant flight for at least 3 – 4 mins.



Thanks again people, you are a great help. Will post more when I get things sorted out.

Maybe my EP settings are off. If somebody can post a screenshot of their EP on their TX config especially on the HK T6A V2, I would be very grateful.

I will also post a video of the problems I am facing.

siddaniels

A successful Sunday...

I finally got the Quad to fly for a good 3 mins.

I made a couple of changes to the FC mounting on the frame.

I removed the foam and Velcro base I was using to hold the FC in place and instead used four blocks of cardboard (made by sticking matchbox covers one on top of the other with fevicol)



I stuck the blocks to the FC using fevicol and then fixed the four blocks to the frame using epoxy.



The FC is now firmly stuck and doesn't move at all. The down side, I think is that due to the lack of damping material the FC board will have a lot of vibration to deal with.

Also changed my Tx calibrations... (HK T6A V2 - Mode 2, Type : Acro)

Here's a screenshot of my Tx EP settings ( CH 1 – aileron, CH 2 – Pitch, CH 3 – Throttle, CH 4 – Yaw)



When binding I kept the throttle trim at 0 ( Or right at the bottom ) as suggested

Before putting the Tx on again to arm the quad I put the throttle trim at Full ( Or right at the top ) doing this lets the green line showing my throttle stick position in T6config, go right to the end.

Should this trim change make a difference or was I just lucky...??? Any suggestions Seniors...

arun.sreelakam

I will make build video tomorrow.. to make things easier..
Don't know why you are fading this much problems..
So get back here by tomorrow...
::)::)

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Turnigy i10|Flysky 9xb|Hoverfly quadcopter|Arduflyer apm 2.5 with gps|Pixhawk|Homemade micro night vapour|Homemade ornithopter(in progress)| Reptile Quad with Gopro Brushless gimbal | Naza v2| APM 2.6 with GPS | Micro quad self made | FrSky| v911 Helis | 1200mm Hexacopter with 5d gimbal | 1300mm x8 With Red Gimbal | 1000mm Octo|

saintofinternet

i recently bought this mini quad parts from satya and have entered the field of RF for recreation ( i earn my bread and butter through RF communication ) and assembled it though was stuck at the final stage of plugging the motors in the FC and searching a little got me the following page... :) happy to share...

HACKMODS --> http://www.hacksmods.com/2013/01/wltoys-v939-flight-controller/

it is for this specific V939 FC which comes in this kit....

now hunting for a TX radio... which is out of stock almost everywhere in this country.... at this moment... cannot fly anything till then sadly  :(

siddaniels

@ arun.sreelakam

Eagerly awaiting the video sir. :salute:

siddaniels

@saintofinternet

Real Bummer!!! when you get stuck like that its a real pain. The waiting...

I busted a motor during my first build so i had to order a pair from Satya sir. As always, the order from quadkopters.com came at super fast speed... so i was back at it.

siddaniels

Here is a video of the quad flying (apologies for the low quality. shot on a web cam)

http://www.youtube.com/watch?v=tlkfiNs_y9c&feature=youtu.be

Also i had mentioned certain issues i was facing. These are not Problems as i'm having a ball of a time flying this awesome quad  either way. I'm am just trying to understand the tuning process of the quad for best possible flight. So any input on that from the Seniors would be highly appreciated.

For anybody thinking of buying the DIY kit for Quadkopters.com ... stop thinking and JUST DO IT... this is one of best build around.   

saintofinternet

help...help.... as a novice to this field i would like to ask the following question....

how is the wiring from the quad motor to connector??

the quad motor has WHITE & BLACK while the connector to the boards have RED & GREEN... when i connect the +ve and -ve of all the motors.... some are pushing the air up and some are pushing it down...

now i cannot figure out the motor wiring to the board.... used the following post for reference http://www.hacksmods.com/2013/01/wltoys-v939-flight-controller/

frankinsmoke

Using the image on that link check your prop  orientation. prop 1 & 3 should be the same and props 2 & 4 should be the same. The same goes for the wires from the motors. 1 & 3 should have the same wiring - 2 & 4 should have the wiring reversed.
Why dont you post a pic of the quad and someone will definitely be able to guide you better