The invention relates to a method for detecting a variation in distance relative to an axis of at least one point of an object rotating around said axis by a terminal (1) in a position that is stationary relative to the axis (41) and capable of emitting a radiofrequency field to at least one resonant circuit (2) attached to the object. Said method includes the steps including measuring and recording, on the terminal side, a maximum value of a quantity representative of the coupling of an oscillating circuit of the terminal and said at least one resonant circuit; and detecting a variation in said periodic maximum.