Abstract: A device for generating forces that are variable and controllable in amplitude, in direction, and in frequency, the device includes two unbalanced rotors (18, 20, 35 to 38) mounted coaxially in a casing (11). The device further includes electromagnetic drive elements for driving a first of the two rotors in rotation relative to the second of the two rotors, and brake elements (43 to 45) for braking the second rotor (20, 36, 38) relative to the casing.

Abstract: The invention applies to a vibrator comprising two pairs (A, B) of unbalanced rotors (10 to 13) driven in synchronous rotation by a first motor, and a second motor arranged to drive a phase shifter mechanism so as to adjust a phase difference between the first pair of rotors and the second pair of rotors; the system comprises: a sensor (C1) for sensing rotation of a rotor of the first pair of rotors; a sensor (C2) for sensing rotation of a rotor of the second pair of rotors, or for sensing the position of the phase shifter mechanism; means for controlling the rotation of the first motor as a function of the phase and the frequency of a force setpoint signal and as a function of the signals delivered by the sensors; and means for controlling the rotation of the second motor as a function of the phase, the frequency, and the amplitude of the force setpoint signal and as a function of the signals delivered by the sensors.

Abstract: The invention applies to a vibrator comprising two pairs (A, B) of unbalanced rotors (10 to 13) driven in synchronous rotation by a first motor, and a second motor arranged to drive a phase shifter mechanism so as to adjust a phase difference between the first pair of rotors and the second pair of rotors; the system comprises: a sensor (C1) for sensing rotation of a rotor of the first pair of rotors; a sensor (C2) for sensing rotation of a rotor of the second pair of rotors, or for sensing the position of the phase shifter mechanism; means for controlling the rotation of the first motor as a function of the phase and the frequency of a force setpoint signal and as a function of the signals delivered by the sensors; and means for controlling the rotation of the second motor as a function of the phase, the frequency, and the amplitude of the force setpoint signal and as a function of the signals delivered by the sensors.

Abstract: A device for generating forces that are variable and controllable in amplitude, in direction, and in frequency, the device includes two unbalanced rotors (18, 20, 35 to 38) mounted coaxially in a casing (11). The device further includes electromagnetic drive elements for driving a first of the two rotors in rotation relative to the second of the two rotors, and brake elements (43 to 45) for braking the second rotor (20, 36, 38) relative to the casing.