CPO 135° Tricopter Design

[cpo]

First, I have to say that none of this would have been possible with out the initial David Windestål tricopter design! Also, thanks to all of you here who were helping me chase down gremlins this weekend!

Hey gang.. I am finally ready to share my tricopter design and build. I have been working on this custom design for a couple of months. It started with an idea to build around the max field of view of a GoPro, as well as have a body that is designed around the KK 2.1 FC board. What I ended up with was a 135° front arm spread, yet a perfectly symmetrical design that imitates (in balance) a standard 120° tricopter. This of course, came after an exploration in tricopter design theory, of which I created a video for. I also came up with a different way to handling camera vibration dampening with the battery and camera tray. While I haven't mounted the camera yet...its coming soon... I have gotten feedback from others that have implemented my design that it works great. Take a look, let me know what you think. Plans are available for download. I am constantly updating the information on my website.

http://everythingcpo.com/cpo-135-tricopter/

Here's how it looks now -- snipped from one of the videos during some maiden weekend (pre-tuning) flight tests. The battery is currently hanging below the battery tray for testing, but will soon be moved up to the top of the tray, and of course, the GoPro will go on front.

Of course, as per my typical MO, there is a lot of information that is general, and not specific to this build...like videos on the following topics (all available from the main link above):

Tricopter and T-Copter Symmetrical Design Theory
Prepping DT-750 motors for use
Building a wiring harness
Zip Tie Landing Gear
Flashing KK 2.1 Firmware in Windows and Mac
An in-depth look at balancing props and hubs
Basic setup of a KK 2.1 for a tricopter (ESC calibration, ACC calibration, Motor Load-out, Servo direction, Servo rates)

...and more to come. Thanks for taking a look. Feedback appreciated.

 

[cpo]

I just thought I would update this. I just built a "shorty" version of this tricopter and slimmed it down for aerobatic flight, rather than FPV...

This is the "G10 Shorty". I cut 150mm off each boom, removed the camera/battery tray, and made this a bit of a race car version of the larger FPV/AV original. I realize some of you aren't looking for a video platform. This should show you that the CPO 135 Tricopter is a capable acrobat as well. (Just don't rely on my skills to prove it! LOL!)

So I go through the entire re-build in this one video. I fast forward through a lot, and don't go into all the detail that is provided in the CPO 135 Tricopter build videos on my website. This should be helpful as a reader's digest version of the build. And of course, I do get a little bit of test flying in at the end.

I need to start working on my acro settings. Right now I have the stick scaling at 70, and I am going to bump it to 90 next. I also have my gyro rate at 1000 from 500 (it didn't seem to like doing back to back flips in 500). I may try pushing that to 2000 next. And of course, I need to work on my piloting skills. I think It's time to start throwing a little more throttle up in with the flips to hang onto some altitude. I'll happily take some pro tips on acrobatic tricopter flying!

Oh...I throw in two extra nuggets...

1. My new preferred method for soldering bullets using a torch.
2. Removing hot glue with alcohol.

Those extra tips are at no cost to you. My gift!. : )

 

[FinalGlideAus]

CPO, thanks for the many "how to video's". Some helped me a lot like how to flash the KK2.

I've been pretty much concentrating on doing tri aero's the last month while I wait for the Dominator HD's to come out. I took inspiration from Matt Hall's simple copter kk2 setup. For multiple flips with energy you'll want stick scaling around 120. I run about 40% expo. Rudder stick scaling is around 90 but I also bumped up the rudder P limit a fair way and this allows some wicked yaw maneuvers.

I'm not sure what motors you have but you really want higher kv motors with smaller props. I'm running NTM 2826 1200kv with 9x4.7 props. I just moved up to 4s and the extra power for manouvers is AWESOME! it is exactly what it needed.

I'll have to sit down and watch your video and I'll try to post some of my amateur acro video when I get a chance. I just had another crash this morning that tried to disassemble the tricopter. Two broken arms, two broken props and a smashed kk2 LCD screen. I've been trying something that I can only describe as a snap roll for a tricopter. Full elevator and aileron and then feed in full rudder and add power. With a 4 cell you need to hang on !

 

[cpo]

Thanks for the feedback. Right now I am running DT750s with larger props...originally working for a smooth FPV machine. I think I can get some decent spunk out of these motors, but I agree they may be a little low on KV for a super agile machine.

I have considered trying 4S...but I haven't tried it yet. I have a couple of 4S batteries laying around, so I may give it a try soon.

I am getting great tuning tips from folks since I posted that video... I updated to the latest Steveis firmware as well and bumped up the stick scaling. It was snowing here yesterday, so I didn't have a chance to get any test flights in yet.

 

[FinalGlideAus]

I started on the stock stick scaling settings and each time I went out I bumped it up by about 10 and added some expo to suit and flew a couple of batteries. Before I knew it I was at 120.

I'm still running KK2.1 FW 1.12 beginner so am probably missing out on some nitty gritty stuff but the tricopter is handling great. Mind you I now can't change anything until I get a new LCD :-(

 

[cpo]

Thanks FinalGlideAus. Here is a test flight today with Steveis KK2.1 1.14S1 Pro loaded (servo moved to M7) and upped the stick scaling to 100 on Ail and Ele (90 on Rud). Getting close. I think I will bump the scaling up a bit more.

 

[moldavia]

Great job cpo. That looks like a good handling tri. This is what I'm hoping to get to sometime soon, is an acro tri to have fun with.
I did enjoy your videos on tricopter theory, and openTX on the 9XR. I learned quite a bit from those. Keep it up!

 

[cpo]

Thanks!

Great job cpo. That looks like a good handling tri. This is what I'm hoping to get to sometime soon, is an acro tri to have fun with.
I did enjoy your videos on tricopter theory, and openTX on the 9XR. I learned quite a bit from those. Keep it up!

 

[FinalGlideAus]

Nice going CPO. Last night I went through some older footage I shot and cut it together along with some crashes as a bonus. It's all only 3 cell flying though so I'll have to get some 4 cell action. When I work out to how upload to YouTube in HD ill post it tonight.

 

[FinalGlideAus]

Here's the footage I knocked together. It's before I went to 4 cell but I was still having then. If you can hold out till the end there's some carnage for you . Damage was restricted to props and zipties.

http://www.youtube.com/watch?v=2z76_DnZ0vw&feature=youtu.be