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Define the displacement of a domain/surface relative to another domain/surface

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Hello,

I have a mechanical resonator (a mass hung by springs within a frame where the mass can resonate). The springs that hold the mass I want to compress. I do this now by having a small part of the frame (the slider), "slide" by applying a step displacement. The slider is not connected to the frame in any way.

This is where my problem arises because after having moved the sliders, I want to either rotate or translate the frame. This works, however, because the sliders aren't attached to the frame, they don't move with the frame (which is what I want). This leads me to my question.

Is there a way where I can define the displacement of a domain relative to another domain?

I've made a simplified model of my problem that hopefully helps to illustrate my issues. The springs are compressed, the mass is given a sinusoidal displacement (simulating the mass in resonance) and then the frame is moved in some way. The model shows that the sliders are fixed after the compression and not moving with the moving frame.

I someone could help me with this that would be great!

Thanks!



1 Reply Last Post 26.08.2022, 18:01 GMT-4

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Posted: 2 years ago 26.08.2022, 18:01 GMT-4

I found a solution to my problem. I did it with the help of another example if anyone might still be interested (see the file below).

You integrate a point of the part that you want to use as a reference (I my case the frame). Then you assign the integral (function) to the prescribed displacement of the slider so that the slider will follow the frame how I want it. You can also add other displacements on top. For example intop1(u) + step1(t[1/s]). Note that you can either put it u, v, or w in the function. These numbers represent x, y and z (if I'm correct).

Hope this still helps anybody!

I found a solution to my problem. I did it with the help of another example if anyone might still be interested (see the file below). You integrate a point of the part that you want to use as a reference (I my case the frame). Then you assign the integral (function) to the prescribed displacement of the slider so that the slider will follow the frame how I want it. You can also add other displacements on top. For example intop1(u) + step1(t[1/s]). Note that you can either put it u, v, or w in the function. These numbers represent x, y and z (if I'm correct). Hope this still helps anybody!

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