MATLAB Answers

Simscape Multibody *** Model not assembled: position violation ***

60 views (last 30 days)
Garett Mcculloch
Garett Mcculloch on 3 Dec 2020
Commented: Juan Sagarduy on 4 Dec 2020
Hi, I'm currently trying to simlulate the movement of an RRRP linkage in Simscape Multibody but I am running into an assembly error when running. I Have determined which joint the issue is and have followed this tutorials steps ( https://www.mathworks.com/help/physmod/sm/ug/find-and-fix-aiming-mechanism-assembly-errors.html ) to attempt to fix the problem. According to this I had to allign the axis of the frames to be parellel to each other and I have done so as seen in the picture below.
With the frames rotated like so I am still recieveing the "*** Model not assembled: position violation *** Resolve this issue in order to simulate the model." error when running the simulation. Would anybody know where I went wrong with attempting to fix this?

  0 Comments

Sign in to comment.

Answers (1)

Juan Sagarduy
Juan Sagarduy on 3 Dec 2020
Hi Garett Do you have the chance to share the model? It must be a detail in there that needs sorting out. Br Juan

  2 Comments

Garett Mcculloch
Garett Mcculloch on 3 Dec 2020
Hi, Thank you so much for helping! I've attached a picture of the model below, forgive me if its messy I'm new to this.
Juan Sagarduy
Juan Sagarduy on 4 Dec 2020
Hi Garett
This mechanism is more compex that what one would think. I remember using it for my first Simscape workshop. I guess that there are different approaches and you need to find the one you prefer.
As an attachment, I had the model I've built using local frames for the rods and simualting motion in the x-Y plane (gravity along -Y). Since the mechanism is a kinematic closed path, you need to be able to access the end point from origin through the prismatic joint and slider, and from the path created by the rods. If you do carefully, it works out well.
I am sure that in your case, you did not succeed in reaching the end point transform consistently, and hence the model assembly violation error. Until the model is correctly assembled, it is better not to prescribe any motion as it can complicate the process.
Check this out & Good Luck.
Cheers Juan

Sign in to comment.

Products


Release

R2020b

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by