Build from scratch octacopter

J

joe shedler

Member
Hey everyone,

I thought I would share a cool link with you all.
First some background. I am new to RC's in the air. I've played around with cars for a while, when I stated my current job my manager was in heli's. We started talking RC's and he expressed interest in getting into quads. I thought this sounded like a bunch of fun. We both got little toy grade ones to get used to quads, I eventually ended up getting a 250 racer clone from china and he went with a camera bird. Both of us purchased pre assembled quads, I thought it to be easier for my 1st time around. Since then have been looking at some builds and found it to be pretty interesting. Then I came across this instructable for a octacopter.

http://www.instructables.com/id/Octocopter-AIO-pro-flight-controller-A2212-motors/?ALLSTEPS

It is an amazingly simple design and I want to build one. :)
So I stared looking at videos for flight controller programming, and plugged my 250 in my laptop after installing openpilot. I might be ready to start this (money is the only hold back now) so I am starting to same some cash.
I've gone out and priced the parts I think I need at ali express, and in Canadian dollars (guess where I am located lol) the parts like comes to aprox $300. That blows my mind, seeing the cost of commercially available hex's, and octa's wow, building IS the way to go.

I'll put this out to the community here....

Is there anything different you would do based on what is in the guide linked? I see that guide as being as simple as you can get really. The only mods I am looking at are this:

* 500mm tubes rather than 600mm = makes a big difference in overall cost.
* smaller base / centre board = with the shorter tubes, to make the 6" hang on each of the 8 arms I need to shrink this to about 6.5" x 6.5", and I am using carbon fibre not fibreglass.
* 2212 920kv 3s-4s instead of the 2212 1000kv 3s
* esc to match the motors

I am betting that the 3s performance will be quite close b/c 920 vs 1000 seems pretty close to me. The 4s recommendation is to run 8045 rather than the 1045 props. I am betting this will make it much more nimble, with smaller blades and more motor speed it should be quite a different flight experience.

cheers everyone have a good one,
Joe
 
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What you listed are pretty good ideas. I have tried to make a multirotor industructable, it was plenty strong (I could jump up and down on the frame), but even that did not make crashes harmless. So I see no problems decreasing to tube size.

So what are you planning on carrying?
 
Welcome to the forum Joe! That's a great idea for a multi! The ability to make it any size you want is a big plus.
The A2212's used in the video are SunnySky Angel series. A motor built to a price point rather than built for quality. One failed him early on. You get what you pay for. Don't buy cheap. It will just cost you in the long run.
920 kv with 10" or 11" props and 3s batteries would be a great combo. The 3s with larger, low pitch props will give you more lift and longer flight times. A 4s with smaller, higher pitch props will give you more thrust with higher speeds and less flight time. The 3s combo will be more stable, great for video for example. The 4s combo will let you tear holes in the sky.
One hint; make your battery wires as short as possible and make the motor wires the long ones. Put a twist in the wires. It will help with interference.
Keep us posted as you proceed. We all love spending other peoples money! ;)
 
HDtallrider said:
Welcome to the forum Joe! That's a great idea for a multi! The ability to make it any size you want is a big plus.
The A2212's used in the video are SunnySky Angel series. A motor built to a price point rather than built for quality. One failed him early on. You get what you pay for. Don't buy cheap. It will just cost you in the long run.
920 kv with 10" or 11" props and 3s batteries would be a great combo. The 3s with larger, low pitch props will give you more lift and longer flight times. A 4s with smaller, higher pitch props will give you more thrust with higher speeds and less flight time. The 3s combo will be more stable, great for video for example. The 4s combo will let you tear holes in the sky.
One hint; make your battery wires as short as possible and make the motor wires the long ones. Put a twist in the wires. It will help with interference.
Keep us posted as you proceed. We all love spending other peoples money! ;)
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Hahaha exactly, we'd be build and design multirotors all day if we could just afford the parts xD
 
HDtallrider said:
The A2212's used in the video are SunnySky Angel series. A motor built to a price point rather than built for quality. One failed him early on. You get what you pay for. Don't buy cheap. It will just cost you in the long run.)
Click to expand...
The SS Angel's are purple. What he is using are these:

http://www.ebay.com/sch/?_nkw=A2212 13T 1000KV&_sacat=See-All-Categories

Buying 10 for about $70 will give you 2 spares. Would also be a good idea to oil the motor bearings for every 2 hours of flying time as these bearings are of a lower quality.

If you watch some of his other vids, he uses these motors a lot on his builds and the performance appears rather good.
 
RGJameson said:
The SS Angel's are purple. What he is using are these:

http://www.ebay.com/sch/?_nkw=A2212 13T 1000KV&_sacat=See-All-Categories

Buying 10 for about $70 will give you 2 spares. Would also be a good idea to oil the motor bearings for every 2 hours of flying time as these bearings are of a lower quality.

If you watch some of his other vids, he uses these motors a lot on his builds and the performance appears rather good.
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You have to be careful using cheap parts, a failure is likely, and will cost you a lot more than better motors.
 
RGJameson said:
The SS Angel's are purple. What he is using are these:

http://www.ebay.com/sch/?_nkw=A2212 13T 1000KV&_sacat=See-All-Categories

Buying 10 for about $70 will give you 2 spares. Would also be a good idea to oil the motor bearings for every 2 hours of flying time as these bearings are of a lower quality.

If you watch some of his other vids, he uses these motors a lot on his builds and the performance appears rather good.
Click to expand...
I admit that I did not look up the ones he referenced. In the past SunnySky used the A prefix to identify Angel motors. Any idea what these motors are? 8 motors of any kind will give decent performance on something that light.
GJH105775 is correct in saying that cheap parts will jump up and bite you when you least expect it. They always cost more in the long run. Imagine 2 or more motors failing while you have a nice camera on board.
 
Wow, I got great response to my post. Thank you to all who added their $0.02.

I'll try to answer some questions and make comments on posts in order all in 1 post to save multiple on multi posting :)
I am new here but that is a common rule in forums.

@GJH105775
1st things first.... Lets get priorities straight right off the bat. What distro do you use? I am also a diehard Linux guy. I run Ubuntu at home and Redhat/CentOS at work. Yes I am lucky enough to have a job as a Linux admin :)

Ok now that we got that out of the way, I saw your 1st post asked what I wanted to lift with this. To be honest my planned build is 500% over kill. Really I am looking for something nice and steady to lift a mobius or a gopro knock off (leaning towards this http://www.banggood.com/EKEN-H9-WiF...-HD-4K-SPCA6350-HDMI-2-Inch-LCD-p-994488.html) with a gimbal. :p

And as for the decrease of the size, I think this will help flight, making the large square air dam smaller, and I am assuming that lowering the size will make it more rigid and stronger. To make up for the lost surface area I plan to add a a second level with some risers if needed. ie: battery space :)

I wasn't going for indestructible, but I did figure that the carbon fibre material I choose with the size reduction should give me some decent strength :)

* most of my thoughts here are assumptions as I don't have the past experience to back up any claims

@HDtallrider
Thanks so much for the welcome :) After the response to this post I do feel welcome :)
I agree, with your statement on the build being totally customizable. That and how dead simple it looks is what got me so interested in this. Before seeing this post I had no intention of jumping into a build, then I came across that link lol.

Thanks for the motor info, 3s vs 4s. You confirmed what I was expecting to get from that upgrade in the build.
I was considering these. They are a little more expensive but, its an upgrade right :)
http://www.aliexpress.com/item/4x-2...SC-Quad-Multirotor-X525-F450/32343184580.html

I had not heard of the wire trick before. Like I said earlier I am used to rc cars, 1 motor 1 esc, much less interferance :) thanks for the heads up.

@RGJameson
Nice call on the past use of the motors listed. Looks like he does have some decent success with these. I used to look at purchasing prebuilt solutions, so even with an upgrade to motors this is still less than half of the costs of decent quads, and its got 8 motors :)

If I was looking at keeping the cost down everywhere possible this would be great info, but I think I am going with 4s capable systems.

@ GJH105775 & HDtallrider
I agree, saving a little now, can cost you much more down the road. Not just a camera, imagine you are on an fpv flight and the bird goes down with a bad motor. What do you do? Hope that the video feed is still intact to help find it.
Good thing this build has 8 motors, I hear you can deal with a blown motor/esc/prop and still get home. :D


It will probably be a few months till I get very far into this build. Time is not a luxury I have a lot of right now, but I was thinking of getting the frame parts soon, and at least start. Hopefully by the time I get something put together I will have the cash flow to get some electronics :)

I'll post updates as they come along. I am excited to get this built and tested over the winter for some nice spring and summer flight videos to post up.

Have a good night everyone, and remember a forum is only as good as the community behind it!
Keep up the good work!
 
Oh I just thought of another question. When mounting the flight controller is it best to mount directly to my frame, or use a stabilizer like for the cameras?
I ask because I saw a number of retailers on aliexprexss saying no stabilizer included, must purchase separately.

While on the topic of flight controllers, does anyone know much about the apm2.8 board? I see it about $20 cheaper than the multiwii used in the guide.
apm2.8
http://www.aliexpress.com/item/F145...2345309779.html?spm=2114.01020208.8.38.Z8sT0q
multiwii
http://www.aliexpress.com/item/CRIU...est=201556_6,201527_4_71_72_73_74_75,201560_4

I have no experience with either of these. I have a cc3d in my 250 racer. I'd appreciate the communities thoughts on these 2 options.
I did look at naze32 but I only saw 6 outputs so that's out.

Thanks everyone,
 
joe shedler said:
Oh I just thought of another question. When mounting the flight controller is it best to mount directly to my frame, or use a stabilizer like for the cameras?
I ask because I saw a number of retailers on aliexprexss saying no stabilizer included, must purchase separately.

While on the topic of flight controllers, does anyone know much about the apm2.8 board? I see it about $20 cheaper than the multiwii used in the guide.
apm2.8
http://www.aliexpress.com/item/F145...2345309779.html?spm=2114.01020208.8.38.Z8sT0q
multiwii
http://www.aliexpress.com/item/CRIU...est=201556_6,201527_4_71_72_73_74_75,201560_4

I have no experience with either of these. I have a cc3d in my 250 racer. I'd appreciate the communities thoughts on these 2 options.
I did look at naze32 but I only saw 6 outputs so that's out.

Thanks everyone,
Click to expand...
I mostly use Debian at home, but it is modified so that you can choose the GUI at login, so I use Mint-KDE/Mint-Cinamon/Ubuntu/a couple others hahaha. I have used about anything Debian based, and have tried a few others such as Fedora, Arch, and non-Linux based Free-BSD, Solaris..... so yeah I have tried quite a few of different OSes hahaha, Debian Based Linux is perhaps my favorite simply as I don't have to relearn the CLI to use it xD. I started on Ubuntu 8.10, and have not regretted leaving Windows as my main OS since xD

APM is a lot easier to configure as it has a GUI, and MultiWii is more open with it's source, both are Arduino based. If you are going to get a GoPro knock-off get the Xiaomi Yi, it is really nice, also take a look at the Runcam, it is a big improvement over the Mobius. Take a look at this Gimbal, really nice I have one running my Runcam, but it was designed to do the GoPro.

Twisting the signal and the ground works just like UTP cabling such as Cat5, the ground eliminates the cross-talk.
 
@GJH105775
Debian Based Linux is perhaps my favorite simply as I don't have to relearn the CLI to use it xD. I started on Ubuntu 8.10, and have not regretted leaving Windows as my main OS since xD
Click to expand...

I totally know what you mean there. I work on RedHat CentOS cli only at work, and I am on Ubuntu with unity at home. I am no where near the cli guy at home as at work lol, sure most programs are the same but some core functions are controlled differently ie how services are controlled, and locations of files are never where I expect them to be haha. At least once a day I type a RH command into my Ubuntu machine or go looking for a file in a RH location at home and get the all too familiar file not found error.

I've bounced around a few distros like you have and in the end wound up where I started. Funny how it just felt like home after searching for something new, I just never got settled in anywhere else. RedHat doesn;t have the desktop support I want, and Fedora just didn't really feel right. Mint was close, Pinguy was fun for a while but bloated. Ubuntu was easier than learning new habits.

Back on topic for the forum :)
I liked the setup on the apm better than the multiwii, and I read that I can get side pin out rather than top pin out which will be nice if I go with a second level on risers. Not to mention it was a little cheaper. I was just not sure if this was 'cheaping' out on what should be a quality part on you build, or so I assume :) its the brain that controls everything right.

I like what I hear about your apm comments. I think I will be leaning that way.

I was almost convinced to get the Xiaomi Yi, but just recently I ran across that one I posted from banggood.com which looked like it had better looking colour than the Yi. Both of them do what I really want and that's 1080 / 60 and 720 / 120. The mobuis doesn't do that. I also looked at the socoo s700, it does 2k / 30, 1080 / 60, 720 / 120. Its priced a little higher but does come with a lot of accessories, does 2k video, and is waterproof without a case. I am betting its a little heavier though as one trade off.

Once I read the wiring tip I knew what was happening, :) just never thought to use it on the rc till it was mentioned.

Thanks, and have a good one.
 
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joe shedler said:
@GJH105775


I totally know what you mean there. I work on RedHat CentOS cli only at work, and I am on Ubuntu with unity at home. I am no where near the cli guy at home as at work lol, sure most programs are the same but some core functions are controlled differently ie how services are controlled, and locations of files are never where I expect them to be haha. At least once a day I type a RH command into my Ubuntu machine or go looking for a file in a RH location at home and get the all too familiar file not found error.

I've bounced around a few distros like you have and in the end wound up where I started. Funny how it just felt like home after searching for something new, I just never got settled in anywhere else. RedHat doesn;t have the desktop support I want, and Fedora just didn't really feel right. Mint was close, Pinguy was fun for a while but bloated. Ubuntu was easier than learning new habits.

Back on topic for the forum :)
I liked the setup on the apm better than the multiwii, and I read that I can get side pin out rather than top pin out which will be nice if I go with a second level on risers. Not to mention it was a little cheaper. I was just not sure if this was 'cheaping' out on what should be a quality part on you build, or so I assume :) its the brain that controls everything right.

Thanks, and have a good one.
Click to expand...
Haha, will do. It is not cheaping out, APM and MultiWii are just different, but the APM is a lot easier to configure, even though the MultiWii is more configurable. Two different well known products, neither is a knockoff, so you are good haha.

EDIT:
Take a look at this chart.
 
It is not cheaping out, APM and MultiWii are just different, but the APM is a lot easier to configure, even though the MultiWii is more configurable. Two different well known products, neither is a knockoff, so you are good haha.
Click to expand...

Awesome good to know. I'm feeling good about this :)
 
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