- #1
aa2105
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Hi
I am analysing some piping which starts off as being aligned with the global axis system (X Y Z). So axially its X, laterally is Y and Z is vertically upwards. Due to bends etc. the end of the pipe is in a different orientation though still in the same plane - now the local axis system is x y z. However, the software I'm using can only accept global values. I need to impose displacements and rotations at the ends of the pipe. For displacements, this is easy - its simply the displacement multiplied by the cosine of the angle which the pipe makes (lets call it theta) with the global X-axis.
However, I am unsure what to do for rotations. Clearly, as the pipe remains in the same plane the Z axis and z axis will remain unchanged. But X and Y have been rotated by theta.
Now if I want to apply a 1.5deg rotation at the end about the local y and z axes - how can I get the equivalent rotation in global terms?
I hope this makes sense... if not I can add some more detail.
Thanks in advance.
Kind regards,
Adders
I am analysing some piping which starts off as being aligned with the global axis system (X Y Z). So axially its X, laterally is Y and Z is vertically upwards. Due to bends etc. the end of the pipe is in a different orientation though still in the same plane - now the local axis system is x y z. However, the software I'm using can only accept global values. I need to impose displacements and rotations at the ends of the pipe. For displacements, this is easy - its simply the displacement multiplied by the cosine of the angle which the pipe makes (lets call it theta) with the global X-axis.
However, I am unsure what to do for rotations. Clearly, as the pipe remains in the same plane the Z axis and z axis will remain unchanged. But X and Y have been rotated by theta.
Now if I want to apply a 1.5deg rotation at the end about the local y and z axes - how can I get the equivalent rotation in global terms?
I hope this makes sense... if not I can add some more detail.
Thanks in advance.
Kind regards,
Adders