Factor for position percentage

[flecmart]

This is more a question than an issue: I come from germany and have this type of vertical covers, called "Rolläden": https://www.youtube.com/watch?v=_KePLmie7lE

I was wondering if the calculated percentage for positioning might not be correct for those kind of blinds, because at 50 % they are kind of fully down, but with the little wholes still letting some light through.

Could this be solved by incorporating a factor for the calculated percentage?

[basbruss]

The calculated position is correct. In this case, it seems to be that the integration that integrates your covers into HA does not comply with the standards from HA, where 0% means fully closed and 100% means fully open. This can either be some calibration setting in the default app (non-HA) or some (conversion) error in the code that talks with HA.

[flecmart]

I am not saying that the calculated position is incorrect. Also my shutters follow the HA convention where 0% means fully closed and 100% means fully open. The problem is that how the shutters here a physically built that 50 % does not mean that the shutters are halfway open. Because if you start from 0% and pull up the shutters, the first thing that happens is that the differnet shutter rips are pulled open to let a little bit of light through. Then at about 30% open, the shutter starts to physically move up and change its position.

That is why I wondered if the calculated position matches my case here, because I know that in most places shutters work differently. Is my assumption correct? The algorighm exepcts the shutters to cover half the window if the calculated position is 50%?

If that is the case the calculated position does not really reflect the right physical position to block of the glare for all shutters that work like mine. I think the problem could be solved by implementing an offset to the position, where 0% represents the state with the shutter rips pulled open. I guess this could maybe be solved by using https://www.home-assistant.io/integrations/cover.template/ on top of my cover as controllable entity for this integration.

[basbruss]

Ah okay I do understand the problem better now. The integration indeed assumes a linear scale from 0% to 100% for the full extension length of the cover.

I could probably build a feature that can narrow that scale and converts the original calculated position accordingly. Although this can add additional complexity for not affected users with a parameter they don't need/understand.

If that is the case the calculated position does not really reflect the right physical position to block of the glare for all shutters that work like mine. I think the problem could be solved by implementing an offset to the position, where 0% represents the state with the shutter rips pulled open. I guess this could maybe be solved by using https://www.home-assistant.io/integrations/cover.template/ on top of my cover as controllable entity for this integration.

But this seems also a rather good solution. And Imho is preferable since the position of a cover should also be correctly displayed within HA and only within the backend logic of some custom integration.

That said I still can workout a dynamic solution if the above seems not work as expected.

[flecmart]

Hey,

thanks for the input. I actually solved the problem with a template cover and I think you're right that this is the better solution.

If anyone has similar problems, a short explanation of how I solved it.

I had the requirements:

• 35% original should map to 0% new
• 75% original should map to 50% new
• 100% original should still map to 100% new

This cannot be one linear function so I used a piecewise linear transformation with two segments:

1. 35% to 75% original mapping to 0% to 50% new: -> new_position = (original_position-35)/(75-35)x50

2. 75% to 100% original mapping to 50% to 100% new -> new_position = (original_position-75)/(100-75)x50

which leads to a template cover like

cover:
  - platform: template
    covers:
      another_cover_adaptive:
        value_template: "{{ is_state('cover.another_cover', 'open') }}"
        open_cover:
          service: cover.open_cover
          data:
            entity_id: cover.another_cover
        close_cover: # this is so that if I actually want to close the cover fully, the origianl 0% is used and the cover really fully closes
          service: cover.set_cover_position
          data:
            entity_id: cover.another_cover
            position: 0
        stop_cover:
          service: cover.stop_cover
          data:
            entity_id: cover.another_cover
        position_template: >
          {% set cp = state_attr('cover.another_cover', 'current_position') %}
          {% if cp is none %}
            None
          {% elif cp <= 35 %}
            0
          {% elif cp < 75 %}
            {{ (((cp - 35) / 40 * 50) | int) }}
          {% elif cp <= 100 %}
            {{ (((cp - 75) / 25 * 50 + 50) | int) }}
          {% endif %}
        set_cover_position:
          service: cover.set_cover_position
          data_template:
            entity_id: cover.another_cover
            position: >
              {% set pos = position | float %}
              {% if pos <= 50 %}
                {{ ((pos / 50 * 40) + 35) | int }}
              {% else %}
                {{ ((pos - 50) / 50 * 25 + 75) | int }}
              {% endif %}

[Eskander]

Hello, thank you for the nice integration! I also have similar blinds throughout the house and wish there was an option to define the minimum position.

[...] with a parameter they don't need/understand.

I think it would be no more or less confusing than the current parameter to set the Maximum Position of covers.

[basbruss]

@Eskander please open a separate issue with your feature request so I can keep better track of it and the implementation is not the same as this issue