Please, explain how this toy is work

[RomanRodinskiy]

Please, explain how this toy (https://www.weber-holzspielzeug.de/holzspielzeug-holzspiele/klopfspechte/klopfspecht-rot-blau.html) works through Physics view?

 

[Lorentz Jr]

 

The bead would fall down immediately if the bird weren't attached to it. The torque from the bird's weight pushes two points on the inner face of the bead against the pole:  the upper edge on the far side and the lower edge on the near side. The only thing holding the bead up is static friction from that contact.

When the bird is bouncing, it gets upward momentum (and inward rotation) from the spring and goes into free-fall every time its beak about to hit the pole. Then its weight and the resulting torque are temporarily removed from the bead, so the bead loses contact with the pole and falls until the bird stops rising. It should fall even faster when the spring gets curved the other way (concave up) and pushes it down, although that may also limit how far it moves on each swing by pushing it against the pole the other way.

EDIT: You can see the bead alternately leaning both ways in the slow-motion section toward the end of the video. The guy says the impact of the beak pushes the pole away from the bead, but I think that's just an entertaining effect. It speeds up the oscillation, but I don't see why it would affect the bead in any other way.

Now they just need to make a bird that goes up the pole. 😁

Edited November 25, 2022 by Lorentz Jr

[RomanRodinskiy]

Thanks!