APM and auxiliary channels

Navio / Edge Hardware
1

On my quadcopter I have a servo to tilt the camera and a rc switch to turn off and on some led lights. I’d like to control this through my network (4G) connection.

The Navio+ has lots of spare PWM outputs, but from what I can see, I cannot make use of these spare channels from the APM Planner or Mission Planner.

Is it possible to write a python script or similar to control these spare channels? (While ArduCopter is running)

BTW: Just had my maiden with the new quad equipped with Navio+. So far, so good! :smile:

2

You should be able to control a lot of external hardware directly from the APM.
For example, here’s how to set up a gimbal:

In case you need something custom it is possible to set channel output values by sending them to the APM over MAVLink.

Congratulations on the maiden flight!:slight_smile:

3

Hello there!

I’ve build a basic 1 axis (tilt) gimbal for the Pi Camera. I am using an analog microservo connected to NAVIO+ output port 10.

I set up on APM RC10 as stabilize channel for gimbal tilt with RC6 as tilt moving channel.

But when I connect the microservo it does not work as expected… it just seems to “fry”. It just sounds like it was fring… no apparent movement.

Could the problem be related to the frequency of the RC10 output? I suspect my microservo works only at 50Hz but the NAVIO+ is sending out PWM at 400andsomething Hz?

Thanks in advance!

4

mikhailavkhimenia: thanks, I’ve looked more at APM and found all the functions I needed, however as fabiobortoli is seeing, the servo move, but they fry and jitter a lot. I tried some different servos, they all behave similarly.

I connected the servo to channel 6 on the Navio board, and used Mission planner to set the servo output.

fabiobortoli: Did you make any progress with this?

5

found some other posts about RC_SPEED, will try this first.

6

Changing RC_SPEED from 490 to 50 (standard servo pulse rate) did fix it, but this means the ESC update rate is a little too low. I think I could notice it during flight. Did not feel as locked in.

Is it possible to have different update frequencies on different channels?

Alternatively, does anybody know of a device that reduce the servo update frequency?

(I want to control it all through a PC so I cannot connect it directly to a servo output from a RX )

7

I feel I’m talking to my self here :)…

I solved it all by changing to digital servos. They seem to handle the high update frequency without any problems.

8

Unfortunately, it’s not possible to set different frequencies for different channels.
So on copters digital servos are the best way to solve this issue.