Trying to fix the object

[JeffsonYu]

Hi!

Not much clearer really, what I tried to explain is that “moving” and “rotating” aren’t well defined for deformable objects (unlike for rigid objects). If you squash a cube flat on the floor, has it moved down? Or just deformed? it depends on where its center (pivot) is, right?

I assume that by “center” of the object you mean some arbitrary particle or particles of your choice, in that case you can just use an attachment to keep that particle(s) fixed in place. See:
http://obi.virtualmethodstudio.com/manua...ments.html

Hi! Sry to bother you again...yesterday I didn't see the message

In fact, in my task, the softbody objects are actually similar to the rigidbody, that the deformation is very small. So what I want to do, is to fix the center of the mass, so that the center wouldn't move from like (0, 0, 0) to (1, 0, 0). 

Again take the barrel in the demo as an example. Now if we use the ball to hit it, it would fly and the surface would deform. Instead of that, I was trying to stick the barrel on the floor, like using a glue, so that when we hit it again, it would only occur deformation on the surface, and stay put. In most cases in my task, the objects are very similar to the barrels.

I would say that rotation would probably not occur in my task, for the hand grasping controls the whole object. I suppose it is similar with fixing the particles? Possibly I will look for the scripts to see if they helps.

Again thx for your reply.