Patent ID: 8650950

Claim:
A gravity gradiometer for detecting a gravity gradient, comprising: at least two sensor masses that are pivotable about respective axes and each of said at least two sensor masses experiences a respective change in torque in response to a change in the gravity gradient whereby the at least two sensor masses move relative to each other in response to the change in the gravity gradient and wherein a signal indicative of the gravity gradient is generated in response to the relative movement of the at least two sensor masses; an acceleration sensor for sensing a linear acceleration associated with an external acceleration applied to the gravity gradiometer; and an actuator for generating an adjustment force that is dependent on the linear acceleration sensed by the acceleration sensor, the adjustment force being also dependent on a mechanical response parameter associated with at least one of the at least two sensor masses and the adjustment force being applied such that a difference between the magnitudes of the respective torques experienced by the at least two sensor masses, resulting from the external acceleration and in response to the change in the gravity gradient, is reduced.