A roly-poly toy, round-bottomed doll, tilting doll, tumbler or wobbly man is a toy that rights itself when pushed over. The bottom of a roly-poly toy is round, roughly a hemisphere. Many roly-poly toys are hollow, with a weight inside the bottom. It has a center of mass below the center of the hemisphere, so that any tilting raises the center of mass. When such a toy is pushed over, it wobbles for a few moments while it seeks the upright orientation, which has an equilibrium at the minimum gravitational potential energy.
The toy can represent a person, an animal, or anything else. Different toy manufacturers and different cultures produce different-looking roly-poly toys: the okiagari-koboshi and some types of Daruma doll of Japan, the nevŠ°lashka or vanka-vstanka of Russia,[1][2] and Playskool's Weebles. Traditional Chinese examples are hollow clay figures of plump children, but "many Chinese folk artists shape their tumblers in the image of clownish mandarins as they appear on stage; in this way they mock the inefficiency and ineptitude of the bureaucrats".[3] In Japanese a roly-poly toy is called okiagari, meaning to get up (oki) and arise (agari). This characteristic has come to symbolize the ability to have success, overcome adversity, and recover from misfortune.[4]
A toy manufacturer recommends roly-poly toys for small children just developing motor skills; a child can bat at it without its rolling away.[5]
Dynamogene Theater stages a performance called "Monsieur Culbuto", allowing the audience to interact with a human dressed as a roly-poly toy.[6][7]
The Noddy stories by Enid Blyton have characters Mr. and Mrs Wobblyman, who are based on this sort of roly-poly toy.