topic Re: Coordinate in Robot Structural Analysis Forum

Coordinate

Anonymous — Sun, 29 Jul 2018 10:33:38 GMT

Hi,

I would appreciate if someone could help me 🙂

I want to identify loads at the end of a column when I check the diagram for bars, for instance, Fx, Fy and Fz, I am not sure about the result that whether they are in local coordinate system and I need to convert them to global coordinate system, or they are in global coordinate system.

As I need to use the loads to apply them on a node in another model.

Many Thanks

Re: Coordinate

Rafacascudo — Sun, 29 Jul 2018 12:15:37 GMT

All results on diagram for bars are in local coordinate system.
So Fx is axial load( positive=compression, negative=tension) , Fy Fz are shear, Mx is torsion and My Mz are bending moments

Re: Coordinate

Anonymous — Sun, 29 Jul 2018 12:47:29 GMT

I need to make a FE model of my column base, and then apply those identified loads on my model. It mean when I want to apply the loads, I have to convert them to the global coordinate.

Global Local

Fx = Fz

Fy = -Fy

Fz = Fx

Mx = Mz

My = -My

Mz = Mx

Am I rigth?

Many Thanks 🙂

Re: Coordinate

Rafacascudo — Sun, 29 Jul 2018 15:48:27 GMT

Y and Z depends on how your columm local system is oriented in relation to the global system.
This is not clear on your picture

Re: Coordinate

Anonymous — Sun, 29 Jul 2018 19:29:52 GMT

Sorry, I have attached another picture.

I need to make FEM of the column number 6, therefore I need to know the loads at the top of the column in order to apply at the top of my FEM of column-base to see the reactions.

I would appreciate if you could tell me the load value that I need to apply at the node which is at the top of my FEM.

Many thanks

Re: Coordinate

Anonymous — Sun, 29 Jul 2018 21:12:47 GMT

Also, do you know the difference between principal value and detailed in map, please?