Local y axis of twoNodeLink element in 3D model

[chenwangNigel]

Hello everyone,

I have a question about how the local y axis of a twoNodeLink element is determined in 3D model, in case I am not defining it explicitly.

Say I have two nodes:
node(1, 0,0,0)
node(2, 0,1,0)

Then I define a twoNodeLink element as:
element('twoNodeLink', 1, *[1,2], '-mat', *[1,2,3], '-dir', *[1,2,6])

I know the local x axis would be the global y axis. But what is the local y axis in this case?

Thank you for your attension and looking forward to your kind answer.

[mhscott]

The local y and z axes are arbitrary in 3D, so you have to define the local y axis. I'm guessing you want it to be 1,0,0

[chenwangNigel]

The local y and z axes are arbitrary in 3D, so you have to define the local y axis. I'm guessing you want it to be 1,0,0

Thank you Prof. Scott! This is really helpful.

Yes, I want the local y axis to be [1,0,0] in this case. So I would have to define the local orientation explicitly as:
'-orient', *[0,1,0], *[1,0,0]