Abstract: An accelerometer that lies generally in a plane, for detecting acceleration along an input axis. There is a substrate, a generally planar Servo Member (SM) flexibly coupled to the substrate such that it is capable of oscillatory motion about a servo axis that lies in the plane, a generally planar Torque Summing Member (TSM) coplanar with and flexibly coupled to the SM such that the TSM is capable of rotary motion relative to the SM about an output axis that is in the plane and orthogonal to the servo axis, wherein the TSM is mass-imbalanced relative to the output axis, and a generally planar rotor coplanar with and flexibly coupled to the TSM such that it is capable of rotary oscillatory motion relative to the TSM about a rotor axis that is orthogonal to the plane of the members. There are drives for oscillating the rotor about the rotor axis and for oscillating the SM about the servo axis. Output sensors detect oscillation of the rotor about the rotor axis and of the SM about the servo axis.