I enjoy flying RC aircraft and in the last few years I started trying to fly RC aircraft with cameras (FPV - First person view). My current hex-copter is large and heavy and get horrible flight times and the video range is really bad.
I decided to build an new multicopter but nearly every one has a quad-copter. I want some thing a little bit more unusually. How about a bi-copter? You don't see those very often if at all so bi-copter it is!
This thread is meant to be a build log for my new bi-copter!
A bi-copter works by tilting it's two motors to get yaw and pitch movements. Roll is accomplished by making one motor go faster than the other.
For reference here is a picture of a bi-copter some one else has built. You can see the two pivoting motors similar to the bi-copter from avatar.
[IMG]http://i1.ytimg.com/vi/koNSNQ5tUIg/maxresdefault.jpg[/IMG]
Enough history on to my build!
My plan is to build the body on the CNC at my work/school and put a camera on the front in the hope that it will be a viable FPV craft. The frame will be made out of fibber glass sheets (G10) and the arms out of cheap carbon fiber tubing.
Most of the parts have arrived. Here is all the boxes waiting to be unpacked!
[IMG]http://i1101.photobucket.com/albums/g427/kingmysion/2014-06-21125707.jpg[/IMG]
I'll still putting the final touches on the 3D model. I should be able to put that in the next post.
That's awesome! I have the parts for my first quad on their way at the moment and as a result I've been looking around at heaps of videos relating to multirotors and I don't think I've ever seen a bicopter. Looks like a really interesting concept but I'm confused where the pitch is achieved if the motors pivot at the CoG because wouldn't that just move the body while the motors remain mostly tangental to gravity?
Yeah, you need to balance it well, otherwise you'd end up with something that can hardly even fly in a straight line, like this one [url]https://www.youtube.com/watch?v=KJCgVdv6U0I[/url]
And then there's also this factory made Walkera stuff that flies pretty much perfectly [url]https://www.youtube.com/watch?v=AJQ8c7KOYsg[/url]
But in this case there might be more than just one servo per rotor, I don't know, I'm not really an expert on this whole thing (I'm planning to build a quadcopter eventually, but I really can't afford all the parts at the moment)
I put the final touched on the 3D model. I made the parts in creo parametric and assembled them in blender to get a feel for how it will go together.
[IMG]http://i1101.photobucket.com/albums/g427/kingmysion/Screenshot2014-06-29215101.png[/IMG]
The long gray tubes are the carbon fiber square tubing. The length is easy to adjust since it's just clamped in. This makes it real easy to adjust the COG(center of gravity) witch should be right under the motors. Now I just need to mill it out on the CNC.
[I]HiddenMyst[/I] I look forward to seeing your quad-copter. If you want you could make a build thread too.
Like you stated with bi-copters pitch is the biggest issue. There are two way to build them. The first way it to rely on the motors being above the COG so that when you pitch forward the weight pulls it down and keeps it upright. The second way to do it is an oblique bi-copter where the motors pitch axis is rotated 45 degree's off center. This is supposed to fix the issue of the motors acting like gyros and simply staying stationary when the body tilts forward. There's one or two white papers on this type as well as a professional kit. Here is an example of an oblique bi-copter.
[video=vimeo;20173832]http://vimeo.com/20173832[/video]
[I]Thunderbolt[/I] the tail boom is easy to adjust so balance should be a non issue. The first video looks like it suffered from the so called pendulum effect.The oblique design is supposed to remedy that. I sure hope it does... we will see.... That walkera one looks real bitching! I haven't seen that one before! Looks like it preforms well too.
I made an attempt to mill some of the ABS parts today. However I got the scale wrong and it was going to go x2 the depth that I wanted it to go. At least the ABS machines well.
[IMG]http://i1101.photobucket.com/albums/g427/kingmysion/2014-07-01133441.jpg[/IMG]
I think I should be able to mill it out tomorrow. All the surrounding classes are done with exams so no more noise concerns! :quagmire:
The frame is done. Unfortunately a screw go in the way of the swivel mounts and they can't turn the full 45 degree's. Oh well not to big of a deal. Now I just need to install the avionics. Avionics is such a funny fancy sounding word. Who needs flight controllers when you can say avionics instead?
[IMG]http://i1101.photobucket.com/albums/g427/kingmysion/2014-07-04141712.jpg[/IMG]
If any one has any questions or advice so far fire away.
Working on the wiring right now. There's quite a bit given the video system and the lights I plan to install. The maiden flight should take place tomorrow. Lets get this baby in the air!
[IMG]http://i1101.photobucket.com/albums/g427/kingmysion/2014-07-04223629.jpg[/IMG]
That's looking awesome. I received my quad kit yesterday, so I'll film the build or something and hopefully we can get an RC thread going or something.
Quads are awesome little buggers. Welcome to the club! You should make a build log for it but an RC thread would be even better. I imagine there are other Face punchers interested in RC and we won't see much traffic on maker mates.
Also post pics as soon as you start. :rock:
Every thing to do with hard ware is now done. I had a scare with the EL wire because is wan't working. Turns out that there was a short at the start of the wire where the connector meets the el wire it's self. Ended up soldering el wire for the first time. There were so many zip ties that my hands are now sore from tightening all of them. I need to update the KK2 but I'm going to go play kerbal space program for a while and let my hands rest.
The bright led at the bottom is meant to be a landing light and I use channel 6 to turn it on and off.
[IMG]http://i1101.photobucket.com/albums/g427/kingmysion/2014-07-05132957.jpg[/IMG]
Is a KA-50 technically a bi-copter? It has two main horizontal rotors above each other, instead of a horizontal main rotor and a vertical tail rotor.
[QUOTE=joost1120;45303546]Is a KA-50 technically a bi-copter? It has two main horizontal rotors above each other, instead of a horizontal main rotor and a vertical tail rotor.[/QUOTE]
I wouldn't say so, it still works like a normal helicopter, as in, uses swashplates to adjust the pitch of the rotor blades themselves and in consequence the thrust vector, while bi-copters don't have swashplates and rely on adjusting thrust and the angle of the entire motor/rotor for movement.
I'd imagine in the V-22 Osprey the engines' thrust is controlled both by collective blade pitch and RPM, but in RC models like this only RPM control is used, seeing as RC models usually have crazy high power-to-weight ratio adding another servo and the mechanics for blade pitch control would only needlessly complicate it, ruin the battery life and make it annoying to build/program/repair/maintain
How's the build going? Have you had a chance to maiden it yet?
Also I love the idea of lights. How did you set that up to control it remotely? I have a bunch of ideas for lighting effects I'd love to add and have 3 channels to spare on my quad.
I'm thinking of making an RC heli, based on the AH-56. The thing is, I'm not sure weather to make some other guys using his tutorial, then get some guy to 3D print the design, or just try and make it from scratch. Also, whats a good light weight camera to use?
I finally got in a few test flights a little while ago. It's not flying good at all right now and I need to play around with the tuning but I'm stuck at this point. I'll just have to mess around and see what works. unfortunately it flipped over a couple times and the last flip busted a servo.... :( Now I need to wait for the replacements to arrive.
[media]http://www.youtube.com/watch?v=jUQGF00uSEU&feature=youtu.be[/media]
[I]Thunderbolt[/I] was right on the money. The KA 50 would be a co-axial helicopter. The closeest thing to a full scale bicopter would be the osprey. From my understanding the thing that would seperate a mono-copter (or single-copter) from a helicopter is the lack of a swash plate and or adjustable pitch blades.
[I]HiddenMyst[/I] I have the EL wire on a switch so I turn if on or off before I fly. However I wired the landing LED to a reciver controled switch. This tunred out to be over kill and I will proably put the LED on the same switch for the el wire eventually.
Here's the reciver switch I used for the LED. [URL="http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=56254"]http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=56254[/URL]
[I]Window098[/I] I have no idea where you would start on a helicopter. If you haven't made on before I would recommend building a standard RC heli from a kit first. Although I did find a thread on RC groups about custom building one. [URL="http://www.rcgroups.com/forums/showthread.php?t=1177833"]http://www.rcgroups.com/forums/showthread.php?t=1177833[/URL]
For a camera there's the cheap hobbyking king camera. [URL="http://www.hobbyking.com/hobbyking/store/__13434__1_3_inch_SONY_CCD_Video_Camera_NTSC_.html"]http://www.hobbyking.com/hobbyking/store/__13434__1_3_inch_SONY_CCD_Video_Camera_NTSC_.html[/URL]
There is also the better Sony one. [URL="http://www.ebay.com/itm/221425142601?_trksid=p2059210.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT"]http://www.ebay.com/itm/221425142601_trksid=p2059210.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT[/URL]
If your just starting FPV there are also some good kits that include every thing you need such as the camera, transmitter and receiver.
I took another shot at flying it. The copter seems to get into fatal pitch oscillations very easily and I can't seem to stop it. I'll play around with it again tomorrow and see if I can figure it out.
Is it possibly caused by the motor pivots being so close to the cross sectional CoG? Perhaps a weight underneath the copter in line with the motors would help.
I'm just guessing and this is all new/foreign to me.
It's a good guess and it probably contributes to the problem. There is a software fix sugested by Rimcopter over on the RCgroups forums that fixed it.
[QUOTE]In my opinion, your pitching is most LIKELY due to low gain on the Pitch Axis and many will argue this point, but a Bicopter really needs to fly with the ACC enabled. It can react to Pitch changes much quicker than the time required for the human eye to detect any correctional changes required and make any flight adjustments necessary. I Never used a KK board but have seen others use it very successfully on a Bicopter.[/QUOTE]
Managed to get it flying, albeit very badly.
[video=youtube;h9IirChn0qg]http://www.youtube.com/watch?v=h9IirChn0qg[/video]
i'm in the same boat. I've been build an FT Versa Wing. But I can't decide what to get for an FPV system. The FatShark Teleporter V2 or V3 seem great but the image quality and sudden blue screens scare me. What are you using?
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