The present invention discloses a display panel, a three-dimensional display device and manufacturing method thereof. The screw crank extends from the screw thread end to an intermediate angular bend which includes an arcuate portion providing an impact anvil aligned with the screw thread for striking by a hammer to set the screw thread into the side of a tree trunk. The connecting element is in the form of a safety element which, under impact, absorbs impact energy by compressive deformation. The end effector is coupled to the shaft distal end.