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HOW TO MEASURE DISPLACEMENTS IN DEGREE IN STRUCTURAL MECHANICS MODEL
Posted Apr 24, 2011, 5:58 p.m. EDT MEMS & Nanotechnology, MEMS & Piezoelectric Devices Version 3.5a, Version 4.1 1 Reply
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I AM TRYING TO MEASURE DISPLACEMENT OF A MICROMIRROR IN DEGREE,I HAVE USED 3D-MEMS MODULE-STRUCTURAL MECH-SOLID STRESS STRAIN.
SO HOW TO MEASURE DISPLACEMENT IN DEGREE IN THE ABOVE SAID DOMAIN PLEASE HELP ME OUT
SO HOW TO MEASURE DISPLACEMENT IN DEGREE IN THE ABOVE SAID DOMAIN PLEASE HELP ME OUT
1 Reply Last Post Apr 25, 2011, 4:09 a.m. EDT
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Posted:
1 decade ago
Hi
indeed by default there is no angles in 3D solid. in V4 you can use the "Curl of displacement U", in other words, for small angles up to 2-3 degrees ( at most 5-8[deg], above you should use a quaternion approach to get correctly larger angles)
Thx = 0.5*(wy-vz)[rad] Rotation x (Antisymmetric displacement velocity tensor)
Thy = -0.5*(wx-uz)[rad] Rotation x (Antisymmetric displacement velocity tensor)
Thz = 0.5*(vx-uy)[rad] Rotation x (Antisymmetric displacement velocity tensor)
in V4 solid with spatial frame driven by the deformations, you must correct to:
Thx = 0.5*(wY-vZ)
...
Note the upper case X,Y,Z due to the spatial and material frame splitting and renaming
you can also write, in V4
Thx = 0.5*solid.curlUX
...
see example in the attached file, sorry I have only 4.1.0.185 today
--
Good luck
Ivar
indeed by default there is no angles in 3D solid. in V4 you can use the "Curl of displacement U", in other words, for small angles up to 2-3 degrees ( at most 5-8[deg], above you should use a quaternion approach to get correctly larger angles)
Thx = 0.5*(wy-vz)[rad] Rotation x (Antisymmetric displacement velocity tensor)
Thy = -0.5*(wx-uz)[rad] Rotation x (Antisymmetric displacement velocity tensor)
Thz = 0.5*(vx-uy)[rad] Rotation x (Antisymmetric displacement velocity tensor)
in V4 solid with spatial frame driven by the deformations, you must correct to:
Thx = 0.5*(wY-vZ)
...
Note the upper case X,Y,Z due to the spatial and material frame splitting and renaming
you can also write, in V4
Thx = 0.5*solid.curlUX
...
see example in the attached file, sorry I have only 4.1.0.185 today
--
Good luck
Ivar
Attachments: