I have a robot model that I created in OnShape, then I used the OnShape-Importer. After that, I have to make further changes. I need to make adjustments on the joints, create a few new joints and so on.
For example, why is the BallJoint not implemented? After import I get an ugly workaround with proxy prims that try to simulate a BallJoint despite the fact that there is a native BallJoint in Isaac Sim (SphereJoint). This is also bad because the proxy prim has a tiny mass value …
However, that is not my main issue with this simulator (and there are many besides the terrible documentation that is all over the place). Right now I am dealing with a situation, where several of my assembly parts (pretty much all of them) have a DIFFERENT null value as global coords.
I repeat:
I import my assembly. Then it appears, just how I see it in OnShape’s assembly studio.
Then I pick any part of it and set its WORLD coordinates to zero. It then appears SOMEWHERE on the map.
I repeat with any other part. It then appears SOMEWHERE ELSE on the map.
Both parts have zero global coords. Seemingly Isaac Sim works with different global coords or how can someone make sense of this behaviour? This again makes it incredible frustrating when adjusting joints or setting new ones. That is, because the joints base their joint frames on those misaligned part-coords.
Then on top of this, the pivot tool is bugged. Isaac Sim cannot load it right now. I use version 4.0.0.