초록 ▼

An active vibration isolation system (10) includes a plurality of stiff actuators, such as piezoelectric motors (12a-c; 284, 350) which support a small mass (18) inside of a case (300). A passive isolator (20) is interposed between the small mass (18) and the payload mass (M.sub.p). In the instance

An active vibration isolation system (10) includes a plurality of stiff actuators, such as piezoelectric motors (12a-c; 284, 350) which support a small mass (18) inside of a case (300). A passive isolator (20) is interposed between the small mass (18) and the payload mass (M.sub.p). In the instance where the stiff actuators are piezoelectric motors, the sidewalls of the case (300) are used to provide compressive force along the variable length of each of the horizontal piezoelectric motor elements (284, 350) to prevent damage to same. Compensation circuitry (24) is connected between velocity sensors (17) and the stiff actuators to control the variable length thereof in this move-out-of-the-way system (10) and to compensate for resonating modes. Optionally, a payload mass velocity sensor (26) and associated circuitry may be used to provide additional control. Shear decouplers (282a-c; 352, 360) are used in conjunction with the piezoelectric motor elements (12a-c; 284, 350) to minimize the amount of shear force acting on the motor elements.

대표청구항 ▼

[ We claim:] [1.] An active vibration isolation system for isolating a payload mass from a source of vibration, said active vibration isolation system comprising:a small mass;at least one stiff actuator having first and second opposed ends and variable in length between the first and second opposed

[ We claim:] [1.] An active vibration isolation system for isolating a payload mass from a source of vibration, said active vibration isolation system comprising:a small mass;at least one stiff actuator having first and second opposed ends and variable in length between the first and second opposed ends, the first end coupled to said small mass and the second end coupled to the source of vibration;a passive isolator interposed between said small mass and said payload mass, wherein said stiff actuator, said small mass and said passive isolator are interposed between said payload mass and the source of vibration;a sensor coupled to said small mass to generate a sensor signal which is a function of the movement of said small mass; andcircuitry coupling said sensor to said stiff actuator and receiving said sensor signal, said circuitry including compensation circuitry to alter said sensor signal such that said active vibration isolation system will be stable over a predetermined range of vibration frequencies and payload masses, said circuitry further including control circuitry coupled to said stiff actuator for varying the length of said stiff actuator as a function of said altered sensor signal.