Patent ID: 8033170

Claim:
A gravity gradiometer for measuring components of the gravity gradient tensor, the gravity gradiometer comprising: at least one sensor mass suspended by a pivotal coupling which enables movement of the at least one sensor mass about an axis in response to a gravity gradient; at least one transducer for generating an electrical signal in response to the movement of the at least one sensor mass relative to a component of the transducer, the at least one transducer further being arranged for influencing the movement of the at least one sensor mass; and electrical circuitry for receiving the electrical signal from the at least one transducer and for directing an actuating signal to the at least one transducer so that, in use, the at least one transducer functions as sensor and actuator, wherein the at least one transducer and the electrical circuitry are arranged in a feedback loop for controlling at least one mechanical property of the at least one sensor mass.