Abstract: A device (1) for measuring the relative orientation according to at least one degree of freedom for two objects, including a constraint generator (10) suitable for causing a goniometric sensor (40) to move in a plane, having the function of measuring the variation of relative orientation of the two objects in this plane. The goniometric sensor (40) is arranged in a housing (41) that crosses longitudinally the constraint generator (10), which has high flexional stiffness in a first longitudinal plane (?) and a low flexional stiffness in a second longitudinal plane (?) orthogonal to the first (?) . The sensor measures rotations in a plane and the constraint generator induces a rotation in that plane. With the device (1) a data suit (50) can be made for measuring the movement of limbs of an individual. For example, arranging three devices (10a, 10b, 10c) in series, but capable of measuring angles in orthogonal planes, the rotation can be measured of the arm (76) with respect to a shoulder (75) of an individual.

Abstract: A goniometric sensor (1) for measuring the relative rotation of two objects (20, 25) includes a flexible elongated element (2) whose respective ends are connected to the two objects (20, 25) and during whose bending the length variation ?L is determined of one of the fibers (15) not located at the neutral axis (10). This length variation ?L is directly proportional to the relative rotation (?) between the two bodies (20, 25) multiplied for the eccentricity (e) of the fiber (15) with respect to the neutral axis (10). Therefore, it is possible to determine easily the relative rotation (?) by knowing the length of rest L and the eccentricity (e) with respect to the neutral axis (10) and to measure the length variation ?L of fiber (15), for example measuring the movement of an end of a cable located in a hole that contains fiber (15).