Movement transformation system applied to at least two rotary assemblies ER1, ER2 with non-convergent main axes, allowing the transmission of an angular displacement of at least one component 9, 10 of a first rotary assembly ER1 to at least one component 4, 5 of at least a second rotary assembly ER2, the first rotary assembly ER1 being in addition able to rotate freely about a second axis perpendicular to the first, characterized in that each component 9, 10 of the first rotary assembly ER1 is fitted with a mechanical connecting device 12, 13 intended to cooperate with a mechanical connecting device 14, 15 of a component 4, 5 of a second rotary assembly ER2, the devices 12, 13, 14, 15 being configured in such a way as to simultaneously transmit and transform the rotary movement of the component 9, 10 of the first assembly ER1 into a rotary movement of a component 4, 5 about the axis of the second assembly ER2, without inhibiting the rotation of any of the components 9, 10 of the first assembly ER1 about their second axis of rotation, and independently of the operation of the other components of the assemblies.