I cant get M7 and M8 to spin up with the WKM custom motor mixer

[Cheshirecat]

Hi

I currently run my SJ X8 with the standard WKM configuration View attachment 16138
So all top motors run CW and all lower motors run CCW, But i would like to switch it so it runs like 2 stacked quads so alternate motors turn CW then CCW on the top and the same on the bottom as per this diagram.

View attachment 16139

So after programming the Herkules for the correct motor layout i then select the Octo Rotor X option in the WKM Assistant and then hit advanced and enter the following in the custom mixer table.

View attachment 16140

When i use the motor test tool in the MOTOR TEST TOOL M1-M6 all spin OK in the correct sequence but i get nothing at all for M7 - M8 (i am not using F1 Or F2) for anything other than motor control as the gimbal is on a separate RX.
Is it also correct that the WKM software has no apparent button to click that is labeled reassuringly along the lines of OK or Commit when you enter a custom mix and that going back to view it just displays a table full of Zeros (am i actually resetting it by going back to view it) if i hit defaults and go back to select the standard Octo - Rotor X setup all 8 run again regardless of the flash settings in the Herkules.

Am i missing something? making no other changes!! any guidance would be appreciated.

 

[tahoejmfc]

I see that your trying to change direction of the motors and am wondering why, alot of people are flying X8's with the stock rotation direction and it works great. If you do want to change the direction of the motors, you can just reverse 2 of the motor wires into the esc out of the 3 and that will change the direction. but be careful, I don't know if you will flip your copter or mess it up

 

[Cheshirecat]

No, not trying to simply reverse the motor directions, i am OK with doing that :untroubled:
What i am trying to do is add resilience to the system and gain some yaw stability.
With a 2 board Herkules if you configure it so that the upper and lower Herkules boards are effectively two seperate Quads then if you loose 1 off the boards you can have enough lift on 4 Motors to make a controlled descent (depending on all up weight it may even stay aloft) so trying to understand why putting in a custom mix drops 2 of the motors:indecisiveness:

 

[tahoejmfc]

Wow, I never thought of that kind of redundancy configuration. I have some comments about your system (which is very cool)
-Why use a Herkules with a wkm? mikrokopter fc with the herkules and the right radio would give you all telemetry as well as Consumption which is a huge plus. If Dji made their frames with a amp sensor and then added that to say lightbridge or ipad ground station, it would be great. Or if Dji made a separate amp sensor for custom builds in maybe 2 different sizes, 100 amp sensor, and for the heavy's out there a 250 amp sensor.
- are you configuring it with the top bottom redundancy setup because if you loose one esc on a hercules you loose them all like a mikrokopter distro ring? or do they individually shut down? If they do individually shut down then it doesn't matter how your motors turn, the dji way is fine and should be able to run say 7 of the 8 if one of the esc's goes out and you will be able to land safely.
- As for the custom motor mixer settings not spinning 7 and 8, I will ask TahoeEd for help on this one and maybe Sir Bartman has a thought about this one.

 

[Cheshirecat]

Wow, I never thought of that kind of redundancy configuration. I have some comments about your system (which is very cool)
-Why use a Herkules with a wkm? mikrokopter fc with the herkules and the right radio would give you all telemetry as well as Consumption which is a huge plus. If Dji made their frames with a amp sensor and then added that to say lightbridge or ipad ground station, it would be great. Or if Dji made a separate amp sensor for custom builds in maybe 2 different sizes, 100 amp sensor, and for the heavy's out there a 250 amp sensor.
- are you configuring it with the top bottom redundancy setup because if you loose one esc on a hercules you loose them all like a mikrokopter distro ring? or do they individually shut down? If they do individually shut down then it doesn't matter how your motors turn, the dji way is fine and should be able to run say 7 of the 8 if one of the esc's goes out and you will be able to land safely.
- As for the custom motor mixer settings not spinning 7 and 8, I will ask TahoeEd for help on this one and maybe Sir Bartman has a thought about this one.

Hi Thanks for the reply.
I have full Telemtry with the Herkules to My Futaba T14SG as well as on board flight data logger these are all part of the Telemetry optional add on for the Herkules, I get voltage, ESC Temperatures, Pack voltage and cell voltages, altitude and climb rate as well as motor commutation error/stall alerts. As well as the all important battery used capacity read out. The herkules has very advanced built in protection systems so will (i am sure) handle single ESC failures well but you can's really build in too much redundancy (unless it adds weight of course) If i lost a complete Herkules board (for an octo they are actually 2 boards top and botton with 4 motors each) due to say a power failure all the surviving props would be spinning the same way and i would loose control, the designer of the Herkules also states that Yaw stability is improved going the way i am trying to go. Just can't figure out the pesky Custom Mixer and why Motor 7 and 8 do not spin in this configuration. Hopefully the Custom mixer king will see my post, laugh and tell me the really OBVIOUS thing i am missing....

 

[tahoejmfc]

very cool how that functions, I will forward this to the other DJI support guys here in the US

 

[hs_foto]

Hi guys,

I find the custom mixer a bit confusing:

I connected the Hercules to the A2 and Motors according to the Hercules manual for coax Octo and also used their custom mixer. Doing a Motortest I found the motors reacting in a strange order: testing M1 will trigger Front left Top Motor (connected to ESC A), but the Hercules manual drawing calls the Front right Top Motor M1 - does that matter? Or is it just confusing labeling?