Frictionless Axis of rotation 1

[foggybrain]

I want to analyse the force required to compress a spring, the lever has a 'frictionless' pin at the bottom, to rotate around and the spring at the top.

When I analyse the lever bends around the axis(assumes 100% friction) - how can I get it to rotate around the pin freely?

thanks

 

[seymours2571]

Assuming you are using solid elements (blue) to mesh the model as opposed to shell elements, create a rotational constraint by first creating a cylindrical coordinate system in mechanical located at the axis of your pin hole.

Next, create a constraint, but change the coordinate system reference to the newly created cylindrical csys. You should now have new constraint options r, theta, and z. My guess is that you would pin r and z and free theta.

Good luck,

Steve

 

[foggybrain]

cool - worked straight off....spent a whole day yesterday trying and knew I was missing a trick....thanks.