Servo 4 and 6 Output decreasing automatically

I’ve started programming the pixhawk cube orange for a hexacopter and just reached the initial tuning stage. I’m facing the issue mentioned below and I’m not able to tackle it.
When I’m arming the drone (without propellers) and slowly move the throttle in the middle position all the servo outputs are the same. But after sometime, they all become different. Servo 4 and 6 outputs decrease and servo 3 and 5 outputs increase.
Kind request for a help.

This is meaningless. Without props and on the bench that is expected.

Without load or props how does this effect servos or arming? is Arudpilot suggesting to setup a Quad with props doing arming on the bench? Normally installing props is the last thing to do but i have all my fingers. Recently i have been seeing on a new setup that the servos are acting odd. Even showing green but no data on the sliders after a radio cal with a few reboots now everything seems to be fine.

Anyone has the arming button let me know. I think there could be an issue using rudder arming before hitting their arm button that could be confusing the servos.
mRo zero classic with Plane on a tailsitter. Discloser it could be a simple TX issue.

That’s not the question I was answering. What he asked has been asked on the forum countless times. Throttling up a multirotor, or VTOL for that matter, on the bench w/o props will produce the exact results he mentions because there is no feedback to the Flight Controller sensors from commanded action. I was simply saying he is facing no issue.

Actually moving the sticks on the Radio after arming without props will send commands to the FC in addition testing flight mode will also show a change in the FC modes that should only be tested without props on a VTOL. Placing props on during a build is a bad idea. The key is to have a good quality FC and frame placed level on the bench. I would reconsider having people place props when testing. My 2 cents.

Testing like this is fine. as long as you IGNORE that some motors will sometimes not rotate.

The problem is not testing without props, that is fine.
The problem is testing without props, not understanding the results and complaining about it.


Yup makes sense.

I do think there could be some data loss going on as well. In Realflight some of the Q flight modes are being set to zero out of the blue so keep a eye out. Also seeing issues in a new build as well I think it could be a arming issue. I would need someone with a arming button to test.

Again this isn’t what the poster was talking about. He believed he had an issue because he saw this

Predictable and totally expected. There is no issue. That’s what this thread is addressing. It has nothing to do with what’s safe or whether props should be installed at this point. It’s an answer to the specific issue he mistakenly thought he had.

can you detail this I don’t understand and what do the props have to do with it.

In any closed loop control system there is a command signal, a sensor(s) feedback signal and an error signal. The output of this is driven by the error signal. If there is no change in feedback signal to a command signal (increasing error), the output will increase. This is what all of these posts are about. IOW, there is no change in feedback signals when the craft is stationary.

This question asked is very basic. Nothing to see here.

Well i disagree as example to test a bi tailsitter or vtol flaps, one moves the plane or quad. motors and flaps do change props on or off. But don’t forget you have to arm to see flaps move on the bench.

“Nothing to see here.” is this necessary? I again see no need to add props to the mix in the system checks until flying. this is the way I do it for years now.

Did you read this? This is his question. What would be your reply to the reason for this happening?

This is basic Closed Loop control, the answer of which has been provided countless times.

Use the search here for “without props”. That’s it, nothing more. You will find the same answer as has been given here and elsewhere countless times.
What point are you trying to make?

I would not think it has anything to do with props installed. Big Picture I looking for a odd issue I had with endpoints disappearing randomly.

I defer to this statement.

Even when under the circumstances given there was no evidence of a problem? I defer to my initial reply which can be demonstrated on any multirotor tested as the poster has done.

If the craft is on the bench no props and you rotate it ?

Then there will change in signal from the Z-axis gyro. How is that significant to the question asked?

I can start a new thread as not to confuse you.

I’ll demonstrate what the thread poster was inquiring about so you are not confused. What he thought was an issue or a problem is expected behavior under the circumstances given. Read again what he witnessed. Does this look like what he is describing?

Bench Motor Test
Of course it does…

And here is a demonstration of how to properly bench test motors using Mission Planners Motor Test.

Mission Planner Motor Test
The reason there is a difference in Motor Output behavior between these 2 tests is what I explained above,