Abstract: The invention relates to a vehicle having steerable axles. A track guide icle comprises at least one pair of independent wheel axles, and at least two members (14, 15) for measuring the transverse position of the vehicle relative to the track, and it is characterized in that it includes at least one measuring member (20) for measuring the angle of the axles relative to references related to portions of the vehicle, and at least two actuator members (21) for correcting said angles by bearing against said axles, and a servo-control circuit receiving the signals from said measuring members and generating control signals for said actuator members.

Abstract: A position sensor for measuring the separation, in a givne direction (Oy), between a first part such as a datum element of a railway vehicle axle and a fixed second part such as a rail on which said axles runs, includes magnets (11, 12) for producing a magnetic field above the second part (10) and Hall effect probes (15) for measuring the value of the component of the field in said given direction (Oy) with variation in that value being proportional to the separation.

Abstract: Apparatus including a magnet (10) having at least one degree of freedom w respect to a first member, tangent to the direction of measurement and cooperating with a magnetic portion associated with a second member, and a sensor (11) for picking up the position of the magnet relative to the first member. Such apparatus is employed in steerable railway vehicles.