Reduction of effect of vibrations due to drive chain of helicopter

摘要

The method is applied to a helicopter (H) whose main rotor (2) has blades (6) with collective pitch adjusted by a jack (8) and controller (12) responsive to measurements of vibration by sensors (14-16) linked to a digital or analogue computer (17). The computed control signal produces a set of forces and torques in opposition to the effect of the vibration. The sensed parameter may be a stress, acceleration, speed or displacement of the fuselage (22); a parameter of the engine (4); a speed, acceleration, rotation or torque of a shaft; a parameter of the automatic pilot or flight control system; or the altitude of the helicopter or the temperature of its surroundings.