Rotational physics joint not behaving as expected

Dolenchuk

Hello, I'm trying to model a process in RS2019.3 using physics to simulate a robot opening a lid on an object. I've set the object as fixed, the lid as dynamic, and created two rotational joints (long lid with two mounting points). The rotational joints appear to work normally when dragging the lid around, however when I simulate the station, the lid will just swing through the fixed object it should collide against. I should mention this is imported CAD geometry, as I've tried a similar setup using RS solids and it has worked properly. 

I've tried rebuilding collision geometries, using original geometry for collisions, importing from different CAD file types, you name it. The only thing I can think of, is when I view default collision geometry, the lid is partially inside the fixed objects collision geometry (tongue in groove hinge). Would this cause the lid to ignore the fixed objects collision geometry altogether?

Johannes Weiman

Hi,
Collisions between two objects that make up a joint are ignored for reasons that escape me right now.
You have to add an extra object (1:08 in):

https://youtu.be/0AIUM2CZbsI?t=68

ArturoLopez

Hello, 

I had the same problem and I think I found a solution. When you create the Rotational Joint you have to put as First Part your rotatory part and as the Second Part you have to put World, in this way the rotatory object collide with the fixed object and stop.

Furthermore, I recommend you to use "Use original geometry" option for the Collision Geometry.