How to shift a model into a different given position?

[AswinSchouten]

Hello everyone,

I'm fairly new to NX so forgive me if the answer turns out to be pretty straight forward.

I have been give 2 models of a thigh bone and 2 models of a shin bone.
these models can be divided into two categories:

1) Stretched position: the angle between the thigh bone and shinbone is 180°
2) Bent position: the angle between the thigh bone and shin bone is 150°
note that the shin bone remains in a fixed position and only the thigh bone shifts.

The shinbone and the thigh bone are connected by a tendon I had to design myself. its a curved cylinder of which both ends were inserted and constrained in a hole of the thigh bone and shinbone forming a connection between the two bones.

When the knee goes from stretched position to bent position the thigh bone doesn't just simply rotate around the shinbone in one direction, the thigh bone undergoes rotations around its own axis and translations too.
The problem is that i drew the tendon while having the knee in a stretched position and I would now like to know the stresses that are created when the knee goes from stretch to bent position but I do not know how to get the leg from one position to the other.
I was thinking about extracting the position of the thigh bone in bent position and somehow inserting them in the model of the thigh bone in stretched position however I have no clue how this is done or if it's even possible.

If anyone could point me in the right direction I would be very grateful.

 

[KhimaniMohiki]

I would proably create seperate parts for the thigh, shin and tendon and add them all to a parent assembly.
Then set up arrangements for both the straight and bent positions. Create the tendon from Wave linked faces from the bones, it will then update as you change the arrangements.

Khimani Mohiki
Design Engineer - Aston Martin
NX8.5

 

[jerry1423]

what version of NX are you on?

 

[AswinSchouten]

@KhimaniMohiki

All files have been saved in seperate files. I'm not too familiar with the "Arrangement" option but I did some research in the limited time I had today and this seems like something I could use. if I understand correctly I have to add both models of the thigh bone to the assembly and make 2 arrangements.

Arrangement 1: the thigh bone is in the stretched position
Arrangement 2: the thigh bone in Arrangement 1 is aligned with the thigh bone of the bent position

How exactly would I be able to align both thigh bones? just by moving the model around until it approximatly have the same position?
Could you also specify what you mean by creating the tendon from Wave linked faces from the bones. I have read a bit about the WAVE geometry linker and from what I understand is that if i WAVE link the tendon to the two bones and I change the position of the bones, the tendon will deform so that it still meets the applied constraints, correct me if I am wrong.
I don't know if this really matches what you are saying cause it seems like what you are saying has something to do with the design phase of the tendon itself.

@Jerry1423

I am using NX 8.0

Thanks for the replies, I can definitely use the tips you have given.