System for controlling the rotation of the body of a railway vehicle about its longitudinal axis

A system for a first control unit (8) for controlling rotation of a body (5) of a railway vehicle about its longitudinal axis (L) for reducing non-compensated transverse acceleration acting in a transverse direction on passengers in the body, the rotation being controlled by at least one actuator (6) actuated by a servo valve (7) controlled by a first control signal from the first control unit (8), the system comprising:

• at least one gyroscope means (10) having two degrees of freedom for fixing to a carriage (1) of a vehicle and having a first axis (x) of sensitivity disposed in the longitudinal axis of the vehicle and a second axis (z) of sensitivity disposed in a vertical direction, the gyroscope means being arranged for generating a first signal indicating an angular velocity .omega..sub.x of the carriage about the first axis (x) and a second signal indicating an angular velocity .omega..sub.z of carriage about the second axis (z);
• at least one tachometric detector means (13) for generating a third signal indicating a longitudinal speed (v) of the vehicle;
• at least one first integrator means (14) for integrating the first signal over time intervals dt to generate a fourth signal .intg..omega..sub.x dt indicating an angle of rotation .phi..sub.x of the carriage about the first axis (x);
• first calculation means (18) for forming a first product of the fourth signal and acceleration g due to gravity;
• second calculation means (19) for forming a second product of the third signal and the second signal;
• third calculation means (26) for taking a difference between the second product and the first product as a fifth signal indicative of a non-compensated transverse acceleration a.sub.nc :
• a.sub.nc =.omega..sub.z v-g.omega..sub.x ;
• whereby the fifth signal is used in the first control unit (8) to generate the first control signal;
• at least one first accelerometric detector means (27) for fixing to the carriage (1) and generating a sixth signal indicating a transverse acceleration of the carriage, a diagram of the transverse acceleration of the carriage as a function of time comprising substantially a first substantially rectilinear section the value of which increases with an increase in time, a second substantially rectilinear section the value of which remains constant with time, and a third rectilinear section the value of which decreases with time;
• low pass filter means (31) for filtering the sixth signal into a seventh signal which is delayed by a delay time interval .DELTA.t with respect to the sixth signal;
• whereby the seventh signal is used in the first control unit (8) to generate the first control signal;
• signal-forming means (28) for forming a supplementary signal a variation of which with time has a form of two waves of trapezoidal form of opposite sign in which an initial inclined section of each wave coincides with a corresponding section of the fifth signal, a duration of each of the initial inclined sections being substantially equal to the delay time interval .DELTA.t;
• further calculation means (30) for forming at each instant a sum of seventh signal and the supplementary signal as a resultant signal;
• whereby the resultant signal is used in the first control unit (8) to generate the first control signal.