How "Eyeball Glide Ball" toy works?

Question

How this toy works? As you roll the ball on the table, the eye always point up:

(original video source: https://youtu.be/_3kAjWaxM30)

As far I am aware, no magnets are involved in the construction of this toy.

pp.ch.te · Accepted Answer

Probably something like this, where the weight is fixed to the inner sphere (the thickness of the blue layer is exaggerated):

Since the inner sphere is free to rotate, the point opposed to the weight will always point up.

One Answer