coupling two angles or lengths

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Greg_melbourne
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Joined: Mon Aug 02, 2021 7:25 am

coupling two angles or lengths

Post by Greg_melbourne »

OK need help .. again... but this one should be easy for veterans :)

I'm trying to make two scissor like blades close together like scissors.

I could create a spreadsheet variable and attached it to those blue construction line lengths in each sketch, or I can just change the construction line
length in one sketch (or spreadsheet) and it'll change the other sketch, since that variable was bought in using carbon copy so the blue construction line lengths are connected.


but how do i do it so that the blades is still free to move in one sketch, and whatever I change it to in that sketch and it'll automatically update in the other sketch?

I'm guessing the binder tool?
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coupled angles.FCStd
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Shalmeneser
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Re: coupling two angles or lengths

Post by Shalmeneser »

Impossible : circular reference : second sketch can refer to the 1st but the 1st can no more refer to the 2nd.
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coupled angles_SHALM.FCStd
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adrianinsaval
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Re: coupling two angles or lengths

Post by adrianinsaval »

hard to understand what you actually want, but I'll say use an angle constraint instead of that length, make it a reference constraint in one and use an expression with that and a spreadsheet parameter for the aperture angle.
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coupled angles adrianinsaval.FCStd
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Greg_melbourne
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Re: SOLVED coupling two angles or lengths

Post by Greg_melbourne »

Thanks but apologies I solved it ... just clone the part and do a transform of the clone 180Deg.

now you can rotate the original part in the sketch and the opposing part automatically mirrors it
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coupled angles.FCStd
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domad
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Re: SOLVED coupling two angles or lengths

Post by domad »

Greg_melbourne wrote: Tue Jun 28, 2022 8:25 am ........
Hi Greg_melbourne, hello to the Community!
An experiment that can trigger interesting "parametric ideas" in many of us who are passionate and not.
The "dynamic scissor" modeled in two different flows:
- in one body
- in separate bodies
dynamically controlled in real-time, without the aid of the spreadsheet, using a (empty) Sketch which has the sole task, in this case, of "control center" of the amplitude of the opening angles of the two scissors independently (or in a dependent manner by setting the appropriate parameters appropriately).
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coupled angles.FCStd
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coupled_angles.gif
coupled_angles.gif (154.85 KiB) Viewed 519 times
Greg_melbourne
Posts: 46
Joined: Mon Aug 02, 2021 7:25 am

Re: coupling two angles or lengths

Post by Greg_melbourne »

Hi Domad, thanks... yes it's still not quite what I was looking for.

You see the solution to the angle number might be say 43.287Deg

and for my project the only way to ascertain what this angle is, is to move complex parts in the sketch, and solve it that way, then I wanted the other body (and sketch) to move with the changes in the first sketch.

Else using all the other method, I'd be changing an angle somewhere, allowing it to update, zooming in on the part, then changing it again and so and and so forth down to 2 significant figures, rather laborious
domad
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Re: coupling two angles or lengths

Post by domad »

Greg_melbourne wrote: Thu Jun 30, 2022 9:06 am .....
Hi Greg_melbourne, hello to the Community!
I'm sorry I didn't understand if you want cetesimal degrees or sexagesimal degrees?
In any case, just enter the conversion factor in the calculation and that's it.
As far as numeric entry is concerned, you can type in sketch008 (Angles Parameters Command) the format with a comma (centesimal or sexagesimal) with the precision you deem most appropriate.
The attached example, in the previous reply, does exactly what you ask, in fact the angle you enter in the sketch008 (Angles Parameters Command) will cause the rotation of the first rod of the "compass", which will be re-quoted exactly on the second rod of the same width, in fact if you measure the angle between the two rods is exactly double that entered in sketch008 (Angles Parameters Command).
In practice, the rotation you apply on the first rod causes the same rotation on the second.
Unless you want the second rod to move in the same direction as the first.
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