A member the other day asked how to program expo on the throttle channel to help with hover in stabilize mode. So I made this short video on how to do it.

How to Improve Throttle Response by adding Expo to your RC Transmitter Control from Bill Bonney on Vimeo.

or see it on YouTube

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  • Thanks that helps my understanding. 

  • Developer

    Normally you configure the copter to hover about 50% throttle. By using expo you reduce the amount of throttle that is applied for any given stick movement near the 50%. i.e. you need to move the stick more, to increase the throttle. This means you you make the repsonse more docile in the midrange, and you can have less overshoot/undershoot. It's the same thing as when you decrease the P-term in your rate controller everything moves a bit slower, and less aggressive. (but this is only for the midrange, not the complete range)

    Expo means also that the limits are not changed as full throttle is still max-out

  • How does this help hovering in stabilize mode?

  • MR60

    Thx Bill for this excellent tutorial.

    I have the ER9X which is close to the open9x but menus are still different. I will try to post the same explanation for those who have the ER9X. I also combined a switch on the transmitter which allows to either select the normal linear throttle curve or the "expoed" curve.

  • I just flashed Open9x and I was going to set something like up this week. Thanks.

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