Sun responsive facade

Hi everyone and thanks a lot for sparing time to help others.
I am trying to design a responsive facade similar to al bahar tower which should open and close according to sun position to provide visual comfort for users inside.
I have used ladybug sun path to get sun altitude and azimuth angle but i do not know how to connect theses angles to my facade components so they response to sun position. (406.5 KB)

Please internalise the referenced surface (right mouse button -> internalise data)
and other referenced data

Sorry, i do not get it. what do you mean by internalise the reference surface?
Sorry for disturbance (406.5 KB)

I uploaded the rhino and gh file.

Thanks for your guidance.

I don’t know enough about ladybug, but I guess the facade should respond to the direction of the sun?
Now it responds to a projection of the sunposition on a sphere. I have used that point to measure the distance as the input for remap numbers.

And I’ve used another epw file; so you have to replace that.
If you internalise the data of the surface, the point and provide the epw file you don’t have to share a 177 MB file. (405.7 KB)

Thanks a lot for your response.
yes, respond to sun direction i guess ( I want to measure the visual comfort and glare inside the building for occupants eventually so is it correct to consider the sun direction or is there any other option? )
can you please explain why did you make the sphere around the building? is it because sun is far away and the rays will be parallel so we have it come closer? ( sphere radius should be an amount to cover the whole building,right?

I did not know about internalizing data but i come to know how to use it.

You have defined a point attractor for your definition. Initially you created a point, and the coördinates were picked by the uv-slider (don’t know if that is the actual name).
I created a point on a sphere (some sort of hemisphere) , which is the intersection of the sphere and a line between the sun’s position and a center point. I have connected this intersection point to remap numbers. (I am not at my desktop so unable to check)
But I don’t think this is very useful, because it doesn’t account for the parallel rays. Your definition should respond to the direction of the rays in relation to the orientation of the façade, not the distance to a point.

On the top left of the canvas you placed a reference to a surface.
-> click with the right-mouse button on that node
-> a menu pops up, almost at the bottom of the menu click - > internalise data

You are right, i need sun position and its angle change effect on my facade, i guess sun vectors directions is needed. If you figured it out please let me know.
@Joseph_Oster had replied to other similar questions, i hope he replies to mine as well.
Thanks for your help @ME_Mark

I can see that you have created a facade that is responsive to an attractor point on the same surface as the facade but how is that supposed to relate to the sun? All rays from the sun are parallel so I don’t see the analogy to an attractor point?

And there is no way I’m going to find my own ‘_epwFile’ file used by Ladybug!

PAK_IS_Islamabad-Bhutto.Intl.AP.415710_TMYx.rar (334.3 KB)

Yes, you are right there is no need for attractor point since sun rays are parallel.
I do not know how to use the sun rays direction ( output from ladybug) to cause facade components get open or close to provide visual comfort inside.

You said that two days ago in your first post. Why build a model that’s responsive to an attractor point that doesn’t correlate to sun position?

I suppose you could locate a point somewhere such that it “casts a shadow” on the facade surface to effectively become the attractor poiint? But where? And do you want to allow the sun to shine through or create shade with your facade?

I don’t think your facade is designed to follow the sun in either case. Please see this thread:


My GH definition is wrong and it should not contain the attractor point part (i was following a tutorial that made a point attractor and wanted to replace it with sun to work as attractor so i got confused)
Can i use the sun position as attractor point ?
I don not understand the shadow part you are talking about, i do not need shade with the facade.
I want to extract sun vectors directions via Ladybug to link the sun position determination with my facade cells.
I want to do something similar to this article: 2 Daylighting and visual comfort of oriental sun responsive skins A parametric analysis.pdf (3.9 MB)


I’m sorry but even reading this is just way too much work. Good luck.

Thanks a lot for your help so far.

Hi - I’m just wondering if you have reviewed the threads on this topic over on the Ladybugtools forum…

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