How to get the position and the rotation of the gripper tips?

[husk-huz]

Very good work! LIBERO can help me in many works now. But I still have a problem.

I need to know the pose of the gripper tips, which is the red part in this image.
I tried with the depth and the eepose. But it not works when the tips are being obscured. Is there any api for this pose?