This is a 3D-printed, one-piece, pull-frame robotic gripper toy, featuring an exceptionally clever assembly-free mechanical design.

Key Features and Principles

Structural Design: It is printed in one continuous piece, with no screws, adhesives, or other additional components. The moving parts are achieved through carefully engineered clearances inherent to 3D printing. The entire mechanism is divided into two main sections:

The front-end gripper jaws: composed of elastic “bionic fingers” with a corrugated, spring-like flexible structure in the middle that provides restoring elasticity.

The rear-end pull-frame handle: consisting of two nested square frames that transmit your pulling force.

Operating Principle: This is a classic flexure hinge plus lever transmission configuration:

When you insert your fingers into the inner frame of the handle and pull inward, the square frame drives the base of the gripper jaws to move backward.

As the flexible structure at the base of the gripper jaws is compressed, the “fingers” at the front end close inward, completing the grasping action.

Once you release your grip, the gripper’s built-in flexible elasticity automatically causes it to reopen and return to its original position.