Initial Parameters Calculator Plugin

Also the spreadsheet is updated, and hopefully soon the Initial Parameters in MissionPlanner will be updated too.
The only important change is a parameter name-change, no changes to formulas to calculations.

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Just for checking purposes, I entered my prop size and cell count into the spreadsheet and compared against what has been initially set using Mission Planner’s Initial Parameters Plugin. For all values I got the same numbers, with the exception of ATC_ANG_YAW_P. After using the plugin via Mission Planner, I currently have 4.5 for my parameter. Using the calculator, I get 2.5:


When I try to replace “4.5” with the value “2.5” I get a warning that
"ATC_ANG_YAW_P value is out of range. Do you want to continue?"
So I left it at 4.5.

Great spreadsheet.

the initial parameters do not take into consideration the number of blades. Do you think it affects the initial flying experience? for example, 3 blades 11x4.5 and 2 blades 11x4.5.

There won’t be a big difference and tuning will sort it out.
The Accel values are not super-critical, the thrust expo can be adjusted later if it gives you trouble.

As an example for a QuadX8 (octaquad) with 2 motors on each arm, you still just put in the individual prop size in inches. You don’t try to halve or double it just because there’s 2 props in coax configuration on each arm.

If you need to adjust MOT_THST_EXPO

  • set too high you can see instability at low throttle
  • set too low you can see instability at high throttle

The MissionPlanner warning about ATC_ANG_YAW_P out of range is just a warning, you should set the calculated value.

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Do you think MOT_THST_HOVER learned value a good telltale sign? for example above 0.25.

MOT_THST_HOVER will probably be more affected by weight (or weight changes) rather than slight variations in MOT_THST_EXPO. If you do have to change MOT_THST_EXPO a lot I would examine attitude control in logs and probably rerun Autotune.
Ensure you have MOT_BAT_VOLT_MAX and MOT_BAT_VOLT_MIN set correctly.

Is this a hard rule or a recommendation?
MOT_BAT_VOLT_MIN: 3.3v x No. Cells what if my failsafe voltage set it as 3.2v x No. Cells?

You could alter it, but setting your failsafe to 3.2v per cell is risky and the battery may have a short life and there may not be the capacity remaining to complete any failsafe action.
Is it Lipo or LIon?
Unless you’ve got some special battery I wouldnt deviate from the standard values.
If you think you will get some significant extra flight time by lowering the failsafe and MOT_BAT_MIN - I think that would be a mistake.
Like running you car fuel tank to empty before you look for somewhere to fill up - you probably wont make it.

EDIT
If you do have a non-standard battery, then definitely set you values as required.
The spreadsheet and Inititial Parameters in MissionPlaner are just to give a good chance of getting off the ground without having to figure out what to change yourself.

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