position non linearity

[luzik]

My roller shutter moves from full up to down in 20second, but there is extra 3sec move down that locks shutter. Those 50% is far away from 50% shutter clearance.

Tasmota for example allows to configure calibration points
https://tasmota.github.io/docs/Blinds-and-Shutters/#calibration

[Jarnsen]

I think one approach to solving the problem would be to work with 2 additional times.
In full it could look like this:

0% shutter is open
100% shutter is closed but slats still let light through
150% roller shutters completely closed, no more light comes in.

The times are measured from 0 to 100 and from 100 to 150 and vice versa, of course, from 150 to 100 and from 100 and to 0. The values ​​from 100 to 150 and from 150 to 100 are then the lag and the lead for calculating the exact position. And 50% should be in the middle of the window.

Is it possible to implement this?

Here is an example from FHEM

KLICK