A single axis accelerometer comprising a swing arm pivotally attached to a frame is held in apposition to a stop by a threshold force until an experienced acceleration force greater than the threshold force causes a distal segment of the swing arm to release from the stop and move toward a sensor that is activated by a sensor trigger on the distal segment of the swing arm.

An accelerometer comprising a plurality of proof-masses moveable along a measurement axis; a respective spring rigidly attached to each proof-mass, configured to exert an elastic recall on the proof-mass in the measurement axis; and a fixed stop associated with each proof-mass, arranged to intercept the proof-mass when the acceleration in the measurement axis increases by a step. The proof-masses are suspended in series with respect to one another by springs in the measurement axis, the stops being arranged to successively intercept the respective proof-masses for increasing thresholds of acceleration.

An accelerometer includes a membrane, an energy source producing a laser beam which is directed at the membrane causing it to vibrate, and a transparent cap disposed at one end of the energy source. The accelerometer includes a first controller for adjusting an output power of the energy source in a first feedback loop, a second controller for controlling the wavelength of the laser beam in a second feedback loop, and a detector sensing a reflected portion of the laser beam. An acceleration signal is based in part on the frequency of the reflected portion of the laser beam.

A single axis inertial sensor includes a proof mass spaced apart from a surface of a substrate. The proof mass has first, second, third, and fourth sections. The third section diagonally opposes the first section relative to a center point of the proof mass and the fourth section diagonally opposes the second section relative to the center point. A first mass of the first and third sections is greater than a second mass of the second and fourth sections. A first lever structure is connected to the first and second sections, a second lever structure is connected to the second and third sections, a third lever structure is connected to the third and fourth sections, and a fourth lever structure is connected to the fourth and first sections. The lever structures enable translational motion of the proof mass in response to Z-axis linear acceleration forces imposed on the sensor.

A MEMS sensor is disclosed that includes dual pendulous proof masses comprised of sections of different thickness to allow simultaneous suppression of vertical and lateral thermal gradient-induced offsets in a MEMS sensor while still allowing for the normal operation of the accelerometer. In an embodiment, the structure and different sections of the MEMS sensor is realized using multiple polysilicon layers. In other embodiments, the structure and different thickness sections may be realized with other materials and processes. For example, plating, etching, or silicon-on-nothing (SON) processing.

A single axis accelerometer comprising a swing arm pivotally attached to a frame is held in apposition to a stop by a threshold force until an experienced acceleration force greater than the threshold force causes a distal segment of the swing arm to release from the stop and move toward a sensor that is activated by a sensor trigger on the distal segment of the swing arm.

The invention relates to an accelerometer comprising a plurality of proof-masses (M1-M4) moveable along a measurement axis (AB); a respective spring (K1-K4) rigidly attached to each proof-mass, configured to exert an elastic recall on the proof-mass in the measurement axis; a fixed stop (S1-S4) associated with each proof-mass, arranged to intercept the proof-mass when the acceleration in the measurement axis increases by a step; and an electrical contact associated with each stop, configured to be closed when the associated proof-mass reaches the stop. The proof-masses are suspended in series with respect to one another by springs in the measurement axis, the stops being arranged to successively intercept the respective proof-masses for increasing thresholds of acceleration.

An accelerometer includes a planar proof mass mounted to a fixed substrate so as to be linearly moveable in an out-of-plane sensing direction in response to an applied acceleration. The proof mass includes first and second sets of moveable capacitive electrode fingers extending from the proof mass perpendicular to the sensing direction in a first in-plane direction and laterally spaced in a second in-plane direction perpendicular to the sensing direction. The moveable capacitive electrode fingers interdigitate with corresponding sets of fixed capacitive electrode fingers mounted to the substrate. The first set of fixed fingers has a thickness less than a thickness of the first set of moveable fingers; and wherein the second set of fixed fingers has a thickness greater than a thickness of the second set of moveable fingers.

Z-axis teeter-totter accelerometers with embedded movable structures are disclosed. The teeter-totter accelerometer may include an embedded mass which pivots or translates out-of-plane from the teeter-totter beam. The pivoting or translating embedded mass may be positioned to increase the sensitivity of the z-axis accelerometer by providing greater z-axis displacement than the teeter-totter beam itself exhibits.

The invention relates to an optical sensor device comprising a reference body and at least one sensing transducer. The sensing transducer is arranged for receiving an input action, and is movably arranged relative to the reference body for moving relative to the reference body in response to the input action. The device further comprises an optical fiber and one or more transmission arms including a first transmission arm. The optical fiber comprises an intrinsic fiber optic sensor. The optical fiber is connected with a first connecting part thereof to the first transmission arm and with a second connecting part thereof to an element exterior to said first transmission arm. The first connecting part and the second connecting part are on either side of the intrinsic fiber optic sensor. For receiving the input action, a base of the first transmission arm is connected at a first part thereof with the reference body and with a second part thereof with the sensing transducer. The optical fiber is connected at a location along the first transmission arm remote from the base thereby converting the input action received by the sensing transducer into a sensing action applied to the optical fiber such as to modify strain in the optical fiber dependent on said input action.