Tricopter Wiring w/ PX4 on Pixhawk Mini

PX4 Autopilot Configuration & Flight Modes ⚙️
1

Hello all, first post because I prefer to read instead of posting questions. Can’t seem to find the answer to this one, however.

I refer first to the PX4 motor map: https://dev.px4.io/airframes-motor-map.html

Tricopters are missing from this page but are mentioned at the bottom. With nothing more to glean from PX4 documentation, I turned to APM & that didn’t help either. I wired everything like this: http://ardupilot.org/copter/docs/tricopter.html

No luck. I get symptoms like this guy: http://diydrones.com/forum/topics/px4-qgroundcontrol-and-tri-copter-configuration

When I “fly” a mission with no props on, all the motors spin but I get no response from the tail servo so no yaw.

I appreciate any help so many thanks in advance!

megabotz

2

Ok, I can confirm that the motor layout is different for tricopters on PX4. I now have the motors & tail servo set up right.

After looking at the PX4 motor map, you can see that motor 1 is always in the upper right quadrant. That makes motor 1 an easy guess. Going counter clockwise is motor 2 & 3, with the tail rotor as 3. Tail servo at #4. Makes more sense than APM.

Now I just have to figure out why the servo yaws to starboard on power up & I keeps trying to push past the servo’s limit until I arm with the button.

Any ideas?

megabotz

3

Hi, have you progressed with the config of your tri?

I am also building a tricopter with a PX4 FC (Pixfalcon).

What confuses me is that the config seem to be either all CW or all CCW propellers while the frame recommended setup is to have the front propellers rotating in opposite directions…

4

I have got the same issue. When I plug the power on my tricopter my tail servo do the same thing than you megabotz. It go to the left and I have not got any control of the yaw.

Any one have any news for it ?