New Tricopter severe roll on first flight

[aaplmike]

Hey all.

I've built a tricopter based on David's fine instructions, and finally received the props I've been waiting on.
The board is the HobbyKing Multi-Rotor Control Board V2.1 (Atmega168PA), the motors are DT750 Brushless Outrunner 750kv and the props are 10x4.5 SF Props. Radio is Orange R620 Spektrum w/matching receiver.

I had some trouble initially flashing the board, but managed to get it flashed to Tricopter v1.6 by kapteinkuk.

After balancing and confirming prop spin direction from the "Tricopter - Scratch build" video here, I took it out back for a test run-up. The props all started spinning when I brought in the throttle, but wasn't off the ground by half-throttle. I barely touched the right stick and the right-front motor immediately spun up to full speed and flipped the copter over, separating the left motor from the boom.

Can anyone give me some items to double-check before I try again? This is my first tricopter.

Thanks!
#mikec

 

[Cyberdactyl]

On those old boards, it's pretty easy to get your channels and gyros reversed. I'd check that.

 

[Mustang7302]

On those old boards...

This is right where the post needed to stop.

Mike, do yourself the favor and work with more modern hardware. Newer boards have way better gyros, have a self level feature, and an active receiver input feedback so you can make sure everything responds as planned. Since the US warehouse at hobby king is out of stock on the KK2.1.5 boards at the moment, take a look at the Acro Naze32 from MultiRotorSuperStore (optional pre-soldering of pins is worth the minor expense too); it will ship from California and be at your day in a day or two. The Naze isn't as friendly as the KK2, but there is a good amount of documentation around for it and you seem to be able to catch on pretty quick if you were flashing older hardware.

How much all up weight, with battery, does your tricopter weight? If you're not getting lift by 50% throttle, you might consider going to 11x4.7" props.

 

[aaplmike]

Thanks for the feedback, guys.

Yes, I may just go ahead and buy the latest KK2x board or the Acro. Sounds like it'll make things a lot easier.
Mustang...I'm lifting 1lb, 15oz during the testing. That doesn't include the camera.

What's the trade-off with going with a larger prop?

 

[xuzme720]

More amp draw but more lift and smoother flying.

 

[aaplmike]

Thanks.

While I'm waiting for my Naze board, a couple more Q's...

I have the install notes for the HK 2.1 board, and as it's a quadcopter board, it shows the rotations for each motor and how they are numbered. With the Tricopter 1.6 fw, there weren't any release notes that I could see, so it's kind of a crapshoot as far as making sure the right motor is connected to the right output from the board, and that the prop rotations are correct. I'm sure for someone familiar with tri's it's fairly obvious, but in the absence of such experience, can someone give me a good procedure for making sure the setup is correct? I'd like to at least toy with this board to gain some experience before I chuck it in favor of the Naze board (which, thankfully, is very well-documented).

Thanks!

 

[cranialrectosis]

The KK2 boards have an on screen display. KK2s support more copter designs than most and make the setting easy on the board itself (you dont have to flash the board to get a tricopter layout).

In the menu go to motor layout to set the motor layout to a tri-copter. There is a menu selection for show motor layout as well.

In any case, if you are using CW and CCW rotors, as the copter sits facing away from you, motor 1 is top left, motor 2 is top right and motor 3 is at the rear. Motor 1 should spin CW, motor two CCW and motor 3 CW.

On the HobbyKing page for the KK2.1 at the bottom is a link for files, click it and you will find doc. http://www.hobbyking.com/hobbyking/...ntrol_Board_With_6050MPU_And_Atmel_644PA.html

 

[aaplmike]

Thanks, Cranial. That helps a lot.

 

[FinalGlideAus]

Naza doesn't support tricopters and are very limited with what they can do.

Check in the Multirotor top tips sticky on this forum for links to setting up a kk2.

 

[Mustang7302]

Naza doesn't support tricopters and are very limited with what they can do.

The Naze32 does, which is not a typo to the DJI Naza. I currently have the Naze32 on my Bat Bone riding piggy back on a KK2.1; literally, the KK2 is still in the airframe but the Naze32 is doing the flying.