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An active vibration damper system, for bending in two orthogonal directions and torsion, in each of three mutually perpendicular axes is located at the extremities of the flexible appendages of a space platform. The system components for each axis includes: an accelerometer, filtering and signal pro

An active vibration damper system, for bending in two orthogonal directions and torsion, in each of three mutually perpendicular axes is located at the extremities of the flexible appendages of a space platform. The system components for each axis includes: an accelerometer, filtering and signal processing apparatus, and a DC motor-inertia wheel torquer. The motor torquer, when driven by a voltage proportional to the relative vibration tip velocity, produces a reaction torque for opposing and therefore damping a specific modal velocity of vibration. The relative tip velocity is obtained by integrating the difference between the signal output from the accelerometer located at the end of the appendage with the output of a usually carried accelerometer located on a relatively rigid body portion of the space platform. A selector switch, with sequential stepping logic or highest modal vibration energy logic, steps to another modal tip velocity channel and receives a signal voltage to damp another vibration mode. In this manner, several vibration modes can be damped with a single sensor/actuator pair. When a three axis damper is located on each of the major appendages of the platform, then all of the system vibration modes can be effectively damped.

대표청구항 ▼

Apparatus located on a space platform for actively damping structural appendage vibrations along three mutually perpendicular axes of a generally flexible body member attached to a generally rigid body member wherein the apparatus for each axis comprises: means for sensing the inertial acceleration

Apparatus located on a space platform for actively damping structural appendage vibrations along three mutually perpendicular axes of a generally flexible body member attached to a generally rigid body member wherein the apparatus for each axis comprises: means for sensing the inertial acceleration substantially at the end of said flexible body member and generating a first acceleration signal indicative thereof; means for sensing the inertial acceleration of said rigid body member and generating a second acceleration signal indicative thereof; means for determining the difference between said first and second acceleration signals and integrating the difference therebetween to generate a signal proportional to the relative motional velocity at the end of said flexible body member; electrical circuit means responsive to said signal proportional to relative velocity for generating a motor drive signal; an electric motor responsive to said motor drive signal for operating an inertia wheel; and an inertia wheel connected to said motor for developing a torque for damping a predetermined vibrational mode along one of said axes.