Betaflight equivalent parameters for acro mode

I have a screenshot of the rates I use in the Liftoff simulator. These rates are modelled after the beta flight. Is there an equivalent parameter that I can set for aducopter to get a similar performance

Thanks in advance

ArduPilot and Betaflight take very different approaches, so it may be a challenge to get identical results. The following should at least be a good start, so long as the Copter is well tuned otherwise:

ACRO_TRAINER,0
ACRO_RP_RATE,240
ACRO_RP_EXPO,0.4
ACRO_Y_RATE,240
ACRO_Y_EXPO,0.4

Beyond that, read here. It looks like that article needs updating, as the rate parameter units are now deg/s rather than the seemingly arbitrary values that equated “4.5” to 200 deg/s.

ACRO_Y_EXPO and ACRO_RP_EXPO I set to -0.1. I need a slow rate at the start and a fast rate when the sticks are at the end. How can I achieve this

Increase those values to positive numbers between 0 and 1. Closer to 1 is more expo. 0.4 as I suggested is already a fairly significant amount of expo.

A simple search of our wiki would turn all of this information up for you.

Thanks @Yuri_Rage , but I have a hard time understanding what the expo curve would look like. My assumption is ACRO_Y_EXPO/RP EXPO when 0 the commanded rate will be linear. Moving closer to 1 does that mean the curve goes below the linear or above

The value is expressed as a percentage. 0 is linear. As the value approaches 1, more expo is applied. Betaflight uses an identical percentage representation, though I can’t be certain the same curve is applied. It’s reasonable to assume results would be similar, as expo as percentage is a common methodology. You show a value of 0.4 in the LiftOff simulator (which attempts to replicate Betaflight), so I recommended using 0.4 with ArduPilot.

Here are some curves using ArduPilot’s actual expo formula:

(In these screenshots, expo is expressed as integer percentage. To set the parameter accordingly, divide by 100, e.g. 30% = 0.3)

{A5E1E52C-A748-4119-83C9-FD8D9CA49788}

{A9A57F9B-3B4A-4DAC-B3C4-4CB0761B1D25}

{1E955F6E-4928-4476-8CAE-9021E7B55A07}

{7042E051-AD0B-41E7-A556-C0B28F8403DD}

Actually, I can confirm that Betaflight uses a cubic expo curve just like ArduPilot, so using the same value in each should produce nearly identical output curves.

Long story short, if you want ArduPilot RC input to behave like the simulator, use the values I suggested from the start.

That doesn’t mean that your copter will behave just like the simulator or identically in real life when switching between BF and AP. But it should at least be a reasonable approximation, assuming it is properly configured and tuned.

@Yuri_Rage thanks a lot man. You are a life saver. Remind me to buy you a coffee sometime

Lastly, acro mode is as close as AP gets to BF rate mode (nearly identical). If you enable ACRO_TRAINER, you can approximate BF angle mode.

Yes we switched to BF’s curve when all the BF pilots complained about AP’s curve …