Hi,
I want to setup my swash plate servos, but oddly it's not possible to save the MIN/MAX values for the servos 1 to 3. At every restart of the APM the values HSx_MIN and HSx_MAX are set to the defaults (1000 and 2000). Only trim (HSx_TRIM) remains its value.
Is that a known issue? How do I tune (and level) my swash plate then.
My hardware: HK-450TT PRO V2 Flybarless + APM 2.5 (Firmware 3.1.5)
All the best, Markus
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Replies
Hi All!
I have the same problem as Mark.
Is there hope that the problem is corrected in a later FW version?
Baffo
Guys, the HS_Min and HS_Max parameters do not save. Those variables come from way back, and honestly I'm not even sure why they're there.
You level the swashplate using HS1_Trim thru HS3_Trim, and these do save.
To set the swashplate collective travel range, you use the H_Col_Min and H_Col_Max parameters. Those are shown as "Top" and "Bottom" in the heli setup page. The Cyclic travel is set with the Roll Max and Pitch Max settings on that page.
You do need to check the servos do not bind at max collective and max cyclic, but there is no way to limit each individual servo. I will try to fix this in the future. However, I've not actually had a binding problem with the collective travel and cyclic travel are set properly.
Markus,
Have you tried to use the mission planner's trad heli set-up screen? it should be possible there to adjust the swash plate's min and max position and trim the servos. It shouldn't be necessary to modify individual parameters through the full param list (or standard or advanced lists) in the mission planner.
-Randy
I tried it both in the heli set-up screen and the full parameter list. It makes no difference: After the restart of the APM the MIN/MAX settings of the swash plate servos always are gone. This problem only affects the 3 MIN/MAX values marked in the screenshot, not the trim values or the swash travel values. The APM forgets the MIN/MAX settings even if I press the Reset Swash Plate button.
Hi Markus,
Yes, this is a known issue. It's been this way forever. Basically, the system was not set up to remember the Min and Max values for each individual servo. I'm not sure why, this goes way back.
The way you do this is using the Trim value to center the servos. Collective Min and Max to set the collective travel. And then you'll also see Roll Max and Pitch Max. Those limit the maximum Roll and Pitch movements. You should be able to get it working using these. Typically a Roll Max and Pitch Max of 25 degrees is appropriate for most flybarless setup. If you have a weird machine which still binds when doing this, then I'm not sure what the short-term solution is.
Hi Rob,
I encountered the same situation that after pressing the "Save" button in the Heli Setup page, not only the system does not remember the Min and Max values of each individual servo, it upset all the previous settings.
Since this situation goes way back, can I skip this step "Capturing the swash plate range" ?
It seems after I set up the correct collective, I don't have to go thru this capturing step and still get the correct collective. So what is the point of capturing the range ?
Appreciate your advice .
Frankie
Nice explanation Rob. But how can one keep the swash plate level during travel of the swash plate. I mean at center stick the swash should be level but at min or max collective stick input the swash should also be level.
I hope I don't hijack this post, if so please disregard.
I have the similar problem of setting the min and max swash plate travel :--
I set up the maximum pitch (9 deg), hovering pitch (5 deg) and minimum pitch (-2 deg) in my Tx correctly after pressing "Manual" button in the MP, then I set the blade to zero, and I pressed the "save" button. As soon as I pressed the "save" button, the 3 collective pitches changed to much smaller values which one cannot fly.
Pls refer to my posting titled "Capturing the swash plate range" under this link :-
http://ardupilot.com/forum/viewforum.php?f=66&sid=5f8cfcdd6dc91....
Thank you.