How to DIY a crawling crab toy

This homemade little crab does not use feet , can walk on the wool rope. What secrets does it hide? Let’s take a look!
Materials for making little physics gizmos:
Cardboard, scissors, straws, tape, wool, colored pens, coins, buttons, fake eyes
Experimental steps for making little physics little inventions:

Step one: on cardboard Draw a crab.

Step 2: Use scissors to cut it Cut it out.

Step 3: Add eyes to it, and a vivid little crab is made! Step 4: Cut off two pieces of straw.

Step 5: Remove the yarn from the straw Wear it inside.

Step 6: Thread the thread The straw is taped to the back of the crab.

Step 7: Tie buttons on both ends of the wool.

Step 8: Hang the crab on the door handle, grab both ends of the wool, and pull it back and forth. The little crab climbed up!
Secrets revealed in a small physics experiment:
The small crab can climb up by relying on the friction between the straw and wool behind it. As soon as you let go, the friction is gone and the little crab falls off.