Custom surface gripper

Hi, I please understand I am a newbie on such things…
Please understand those non-expert-like words below…

I am currently trying to implement surface gripper class in my custom designed gripper.

I tried step by step given example in :
https://docs.omniverse.nvidia.com/app_isaacsim/app_isaacsim/ext_omni_isaac_surface_gripper.html
And I just want one simple thing: to exchange the cone with my custom gripper.

I brought the gripper using ‘create_prim’:
self.MG10Geom = create_prim(prim_path=’/me_and_my_robot’,usd_path=self.asset_path, position=np.asarray(self.gripper_start_pose.p))

This is a single-joint model so the stage looks like this:

  • physicsScene
  • groundPlane
    • CollisonMesh
    • ColliconPlane
  • DistantLight
  • me_and_my_robot
    • looks (Scope)
    • mg10 (Xform)
      • visuals (mesh)
      • collisions (Mesh)
    • root_joint (physicsFixedJoint)
  • Box

And I applied surface gripper on
self.sgp.parentPath = “/me_and_my_robot/mg10”

Everything except those are the same as provided example code.

Everything occurs no error messages, but the surface gripper is not closing.
I have checked after every line of ‘surface_gripper.is_closed()’, but there is no closing occuring.

What am I doing wrong?
I hope I am providing enough material to create new question.