Alliedsignal Inc.

Honeywell International Inc.

Sundstrand Data Control, Inc.

Ronald B Leonardson

James R Woodruff

Graeme A Blake

Steven A Foote

Paul H Collins

David L Malametz

Douglas C MacGugan

William W Sand

Aiwu Yue

David E Frazier

Jeffrey T Smith

An apparatus and method for force sensing device having a pendulous mechanism proof mass formed in a silicon semiconductor substrate and structured for rotation about an intermediate rotational axis, the proof mass being substantially rectangular in shape with opposing first and second lateral peripheral edges and opposing first and second endwise peripheral edges. A plurality of capacitor comb teeth are formed symmetrically along the opposing first and second endwise peripheral proof mass edges and along the opposing first and second lateral peripheral proof mass edges adjacent to the first and second endwise peripheral edges, and one or more mass reduction apertures are formed in an interior portion of the proof mass on one side of the intermediate hinge axis.

MEMS teeter-totter accelerometer having reduced non-linearty

A Micro Electro-Mechanical System (MEMS) acceleration sensing device, formed of a sensing element having first and second substantially planar and parallel spaced apart opposing surfaces and being suspended for pendulous motion about a hinge axis oriented along a minor axis of the sensing element; and one or more substrates each having a face spaced from one of the opposing surfaces of the sensing element, each of the substrates having pluralities of electrodes arranged substantially crosswise to the hinge axis of the sensing element symmetrically to a longitudinal axis of the sensing device and forming respective first and second capacitors with the moveable sensing element. Each of the one or more substrates optionally including a clearance relief for extending the rotational range of motion of the sensing element.

MEMS enhanced capacitive pick-off and electrostatic rebalance electrode placement

A method for designing a sensor using a dual double-ended tuning forks which provides composite cancellation of second-order non-linearity terms.

Compensation of second-order non-linearity in sensors employing double-ended tuning forks

An apparatus and method for sensing accelerations and other forces. The apparatus having a cover plate having an inner portion and an outer portion, the inner portion being formed with a plurality of spaced apart electrodes projecting therefrom and defining spaces therebetween; and a proof mass having an inner portion being formed with a plurality of spaced apart electrodes projecting therefrom and defining spaces therebetween, an outer portion being coupled to the outer portion of the cover plate with the electrodes being electrically isolated from the cover plate electrodes, and the proof mass electrodes and spaces being aligned with the cover plate electrodes and spaces such that, when the inner portion of the proof mass is deflected toward the cover plate, the proof mass electrodes pass into the spaces between the cover plate electrodes, and a flexible suspension member coupled between the inner and outer proof mass portions.

Small size, high capacitance readout silicon based MEMS accelerometer

The present invention provides an acceleration sensor and an accelerometer having isolation structure formed using a bulk straight wall deep reactive ion etch process, whereby external stress sources are isolated from active accelerometer components.

Combined enhanced shock load capability and stress isolation structure for an improved performance silicon micro-machined accelerometer

An accelerometer formed from a semiconducting substrate and first and second active layers coupled to the opposite surfaces of the substrate. The substrate has a frame and a proof mass suspended from the frame by one or more flexures for rotation about an input axis in response to an applied force. The active layers each include a vibratory force transducer mechanically coupled to the proof mass for detecting a force applied to the proof mass. With this configuration, the transducers are located on either side of the substrate, which improves the differential design symmetry of the force detecting apparatus. This reduces the common mode non-linear response characteristics of the accelerometer, particularly in high dynamics applications, where high performance is required.

Vibrating beam accelerometer and method for manufacturing the same

Accelerometers and methods of forming accelerometers are described. The accelerometers are provided with electrically conductive structure configured for connection with external circuitry. The electrically conductive structure has a folded-back architecture which reduces temperature-induced anomalies which can adversely impact acceleration-sensing function of the accelerometer.

Vibrating beam accelerometers and methods of forming vibrating beam

An inertial sensor assembly (ISA) includes a cluster of three ring laser gyros, each gyro producing an output signal having a pulse repetition rate representative of the rate of angular deviation of the ISA about one of three coordinate axes X, Y, and Z. The ring laser gyros are synchronously dithered at a relatively constant rate. The ISA also includes a triad of three accelerometers, with each accelerometer producing an output signal representative of the rate of velocity deviation of the ISA along one of the X, Y, and Z coordinate axes. A first processor, P1, accumulates the pulses produced by each ring laser gyro over its dither period. The resultant counts are stored in registers for subsequent sampling by the P1 processor at a periodic sampling rate which is greater than the dither rate. The P1 processor then synchronizes each sampled pulse count to a common sampling interval, thereby eliminating errors otherwise caused by using positional data values taken at different times. The P1 processor also compensates the ring laser gyro and accelerometer-produced signals at the sensor and the system level for effects such as temperature, bias offsets, scale factor and misalignment by the use of compensating coefficients stored in electrically erasable, programmable read-only memory. The processed data from the P1 processor are passed to a P2 processor which performs navigational computations to thereby produce computed positional information.

Inertial reference system

A digital accelerometer comprising a linear analog accelerometer and a digitizer. The analog accelerometer includes a housing and conductor means extending outside the housing, and is adapted to produce on the conductor means an analog signal representing linear acceleration along one axis. A casing is positioned against the housing so as to form a substantially enclosed space between the housing and the casing. The digitizer is located within such enclosed space and receives the analog signal and produces a corresponding digital signal. An interface circuit is positioned within the enclosed space for receiving the analog signal and producing a second analog signal that is input to the digitizer. The digital signal produced by the digitizer may be conveyed to a location outside the enclosed space and housing by a flexible strip of insulating material having a plurality of conductive strips embedded therein. In a preferred embodiment, the interface circuit is operative to determine the magnitude of the second analog signal resulting from a particular first analog signal, whereby the dynamic range of the digital accelerometer can be modified by modifying only the interface circuit.

Growing community of inventors

Redmond, WA, United States of America

Ronald B Leonardson