AQ Motor Redundancy?

[13brv3]

Greetings,

I've been testing some odd configurations, which should have redundancy, and was surprised when I couldn't turn off a motor and have the copter still fly. I thought maybe I misjudged the configuration, but now I'm back to a fairly normal Y6, and I can't fly with one of the rear motors turned off. I've done this many times with other controllers, so now I'm thinking the default range of settings for the AQ may not be very tolerant of failed motors?

It does fly with one of the front motors off, but it should also fly with a rear motor out. FWIW, my mixer has 100% everywhere except for the front motors, which have 50% for pitch. PIDs are near default. The rear motors rotate opposite of the front motors.

Can someone with a Y6 try disconnecting one of the rear motors to see if yours will fly? Mine lifts off in a slightly nose up pitch, then even full forward stick won't level it, and I have to chop the throttle to get it on the ground before it hits something (me). My only theory is that the default PIDs don't allow enough motor control to let the remaining motor make up for the missing motor.

Cheers,
Rusty

[LPR]

Rusty

I played with the octos motor mix for a long time and I found for the motors, props and batteries I am using that 50s and 70s worked best. Take a look at your motor logs and try motor mixes looking to keep the PWM from being clipped.

If I had a hex I could maybe help more.

Larry

[13brv3]

Hi Larry,

I spent some time reading the 11 page "understanding the mixer" thread a few days ago, and I hate to say it, but I didn't end up understanding much. There seem to be several theories about how it's supposed to work, but no definite conclusion. My take is that you should set the mixer with the highest numbers you can, which also balance the pitch and roll reaction.

In the case of the Y6 I was testing, I had 100 in each of the rear motors, and 50 in the front, so I don't think that should have limited the ability of the remaining rear motor when I shut one off. The Y6 is known to be the minimum configuration for full redundancy, so maybe AQ needs more. I'm currently testing an asymmetric 4/8 motor frame, and when I get to the 8 motor config, I'll try the redundancy again. Hopefully that will all work OK, since it's essentially an X8, and redundancy should be a given.

Cheers,
Rusty

[LPR]

Rusty

I'm still a little confused on how the AQ motor mix is setup. I know if your motors are not all vertical it can have a big effect on being able to fly with a motor off. If a motors PWM is maxed out there is nothing left for changing attitude or yaw.
My octo flies very and has been able to perform a mission with a prop gone or a motor stopped. I'm not sure a mission can be always be done if anyone of the motors are stopped because if have not tested all of them.

[13brv3]

Hi Larry,

I'm convinced that mixers are always a source of confusion. In the MK world, they used to tell you to change them if the motors weren't the same distance from the center, then all the default mixer files were 100% for all motors. I tried them both ways, and never could tell the difference. That was years ago now though, so maybe they've changed (doubt it).

For the AQ, I'm going to assume I have it figured out until I find out that's wrong

At this point, I'm guessing it was the PIDs that were limiting me. I don't have the Y6 assembled anymore, so no sense it trying to figure it out now. Once I get the new coax 8 running, I'll be pretty motivated to make sure it's fully redundant. For me, 4 motors will lift anything I need to lift, so any additional motor is there for redundancy.

Cheers,
Rusty