Morning Mats,
It's not just me then.
I was contemplating mechanism dynamics but we don't have flexible beams.
To develop the spring idea a bit further ...
What if the beams are connected by very stiff springs (so they do not contribute to deflections) where the springs are very short (so they do not to significantly affect geometry) ?
You wouldn't need to approximate stiffness then.
(it's still a lot more pre processing than I would want to do ... and a lot more measures)
Charles