Test body equipped with an encoder

A test body for a system for determining a torque applied between two members rotating about a geometric axis of rotation (R), said test body having an internal bushing secured in rotation with means for mounting said test body on one member, and an external bushing extending around the internal bushing while having means for mounting said test body on the other member, said bushings being connected by a deformable structure which is arranged so as to transmit the torque between the members while enabling an angular displacement between said bushings according to the torque applied between said members, said test body being equipped with two rings each carrying a magnetic track which is able to emit a signal representative of the rotational movement of said ring, the rings (5, 6) being fastened respectively on one bushing and the magnetic tracks being magnetized concentrically so that they have a common axis of revolution (P) so as to respectively form an internal magnetic track and an external magnetic track of an encoder.