Help Problem with rods in moving objects

[josemendez]

Hi,
I've recently encountered a problem while working with Obi Rope rods. I created a rod with attachments on both ends, and everything seemed to be working fine. However, when the parent object containing this entire setup (the rod and both attachment transforms) started moving, the rod became very unstable and jagged, it was bouncing back and forth very quickly. This parent object was inside object with Obi Solver component, which was stationairy all the time, and this object was moving relatively to it. I've also checked and the same issue appears when a rope instead of rod was used.

Is there a way for a rod to somehow ignore the movement of parent objects and use local position for calculations, instead of world position? This would be really helpful, because I need to create many objects with rods, where the objects are moving, but the rods inside them are stationairy in relation to their parent.
Thank you for your help

Hi,

Simulation is never performed in world space, but in the solver's local space. See:
http://obi.virtualmethodstudio.com/manua...olver.html


In your case, the problem arises because the objects that the rod/rope is attached to are moving in solver space. You can just have a separate solver as the parent for each object and move the solvers around, instead of the attached objects. Note that you can inject back a percentage of world-space inertia if you wish, using the "world linear/angular inertia scale" parameters.

kind regards,