Seiko Epson Corporation

Kenta Sato

Yasushi Yoshikawa

Masayoshi Todorokihara

Jun Watanabe

Kentaro Yoda

Masayuki Oto

Hisao Motoyama

Naoki Kitahara

A diagnosis method includes: a physical quantity detection step of detecting a physical quantity generated in a diagnosis target by using a physical quantity sensor; a Lissajous figure generation step of generating a three-dimensional Lissajous figure by plotting the physical quantity detected in the physical quantity detection step in a three-dimensional coordinate system including a first axis, a second axis, and a third axis; a vibration plane information acquisition step of acquiring information on a vibration plane of the vibration from the three-dimensional Lissajous figure generated in the Lissajous figure generation step; and a diagnosis step of diagnosing a state of the diagnosis target based on the information on the vibration plane acquired in the vibration plane information acquisition step.

Diagnosis method, diagnosis apparatus, and diagnosis system

A signal processing method includes: acquiring first measurement data based on a signal output from a first sensor configured to detect a physical quantity of a first axis generated by a vibration of an object and second measurement data based on a signal output from a second sensor configured to detect a physical quantity of a second axis generated by the vibration of the object; generating a Lissajous figure based on the first measurement data and the second measurement data; transforming coordinates of each point in the Lissajous figure into polar coordinates and generating time series data of a first angle which is an angle formed between the first axis and a straight line, the straight line being obtained by projecting a straight line passing through an origin and each point in the Lissajous figure onto a plane including the first axis and the second axis; and executing frequency analysis on the time series data of the first angle and calculating a first maximum peak intensity which is a maximum peak intensity in a first frequency spectrum obtained by the frequency analysis.

Signal processing method, signal processing device, and monitoring system

An inertial measurement device includes a first inertial sensor having a first detection axis, a second inertial sensor having a second detection axis defined in a direction opposite to the first detection axis, and a processing circuit configured to execute self-diagnosis based on whether a ratio of an amplitude of an output of the first inertial sensor to an amplitude of an output of the second inertial sensor is within a reference range.

Inertial measurement device and self-diagnosis method of inertial measurement device

A signal processing method includes generating N data sequences by dividing i-th measurement data based on a signal output from an i-th sensor that detects a physical quantity generated due to a vibration of a target object, for each integer i of 1 or more and M or less, where N is a predetermined integer of 2 or more, and M is a predetermined integer of 2 or more, generating an i-th averaged data sequence by averaging the N data sequences generated by dividing the i-th measurement data, for each integer i of 1 or more and M or less, and generating a Lissajous figure in which the i-th averaged data sequence is assigned to an i-th axis, for each integer i of 1 or more and M or less.

A structure is a structure of a quartz crystal substrate having a slit. The structure includes, as an inner wall of the slit, a first side surface, a second side surface, a first end surface, and a second end surface. The first side surface extends along a first direction which is a longitudinal direction of the slit, and the second side surface extends along the first direction. The first end surface is continuous with the first side surface and extends along a first crystal plane of the quartz crystal substrate, and the second end surface is continuous with the second side surface and extends along a second crystal plane of the quartz crystal substrate. In a plan view of the quartz crystal substrate, an intersection point where a first straight line corresponding to the first end surface and a second straight line corresponding to the second end surface intersect each other is located inside the quartz crystal substrate.

Structure, physical quantity sensor, inertial sensor, and method for manufacturing structure

A physical quantity sensor includes: a base portion; a first arm portion, a second arm portion, and a third arm portion that are coupled to the base portion and that are provided with fixing portions; a movable portion disposed between the first arm portion and the second arm portion and between the first arm portion and the third arm portion in a plan view; a constricted portion that is disposed between the base portion and the movable portion, and that couples the base portion and the movable portion; and a physical quantity detection element that is disposed across the constricted portion in the plan view and that is attached to the base portion and the movable portion. Thin portions are formed at least at two positions in at least one of the second arm portion and the third arm portion.

Physical quantity sensor, physical quantity sensor device, and method for manufacturing physical quantity sensor device

An abnormality determination method includes: a first distance calculation step of calculating, based on measurement data of an object, a first Mahalanobis distance in a first unit space corresponding to a normal mode of the object; a second distance calculation step of calculating, based on the measurement data, an (i+1)-th Mahalanobis distance in an (i+1)-th unit space corresponding to an i-th abnormal mode of the object for each integer i greater than or equal to 1 and less than or equal to N, N being an integer greater than or equal to 2; and an abnormality determination step of determining, based on the second to (N+1)-th Mahalanobis distances, one of the first to N-th abnormal modes where the object is when the first Mahalanobis distance exceeds a threshold value.

Abnormality determination method, abnormality determination device, and abnormality determination system

An inertial measurement unit includes: a sensor unit having an inertial sensor; and a first holding unit holding the sensor unit. The first holding unit includes: a first substrate; a second substrate; a plurality of spacers coupling the sensor unit and the first substrate; a first elastic member and a second elastic member provided on both sides of the first substrate via opening parts; a first fixing member penetrating, pressing and fixing the first substrate and the first elastic member to the second substrate; and a second fixing member penetrating, pressing and fixing the first substrate and the second elastic member to the second substrate.

Inertial measurement unit

A vibration rectification error correction circuit includes a first correction circuit that obtains a digital value based on a signal to be measured output from a sensor element configured to measure a physical quantity and corrects a vibration rectification error of the digital value by a correction function based on a product of values obtained by biasing the digital value.

Vibration rectification error correction circuit, physical quantity sensor module, structure monitoring device, and correction value adjustment method of vibration rectification error correction circuit

A physical quantity sensor module includes: a resonant frequency shift based physical quantity sensor whose frequency adjusts with a adjust in physical quantity; a reference signal oscillator which outputs a reference signal; a frequency delta-sigma modulator which performs frequency delta-sigma modulation of the reference signal, using an operation signal based on a measurement target signal as an output from the resonant frequency shift based physical quantity sensor, and generates a frequency delta-sigma modulated signal; a first low-pass filter provided on an output side of the frequency delta-sigma modulator and operating synchronously with the measurement target signal as the output from the resonant frequency shift based physical quantity sensor; and a second low-pass filter provided on an output side of the first low-pass filter and operating synchronously with the reference signal.

Physical quantity sensor module, clinometer, and structure monitoring device

A physical quantity sensor includes a base, at least two arms, a movable plate, a hinge, and a physical quantity measurement element. Four quadrants of the sensor are defined by first and second orthogonal lines. The first line passes through the center of the sensor and crosses the hinge. The second line extends along the hinge. Fixed regions of the sensor are located in the first and second quadrants. No fixed regions are located in at least one of the third and fourth quadrants. The third and fourth quadrants are closer to the base than the first and second quadrants in a plan view.

Physical quantity sensor, physical quantity sensor device, and inclinometer, inertia measurement device, structure monitoring device, and vehicle using physical quantity sensor device

An inertial measurement system includes three acceleration sensors detecting along three orthogonal axes, a display having several display areas, and a processor programed to perform a process. The processor calculates frequencies and spectral intensities of vibrations based on detected time series accelerations by three acceleration sensors and obtains relationship values between the calculated frequencies and the calculated spectral intensities. The processor causes the display to successively display an N-th value, intermediate values, and an (N+1)-th value of the relationship values at one display area in time series.

Display device and inertial measurement system

An inertial measurement device includes: an inertial sensor; a battery supplying electric power to the inertial sensor; a first case accommodating the inertial sensor; and a second case accommodating the battery. The battery and the first case are spaced apart from each other. The second case is fixed outside the first case.

Inertial measurement device

An inertial measurement unit includes: a sensor unit having at least one inertial sensor; a display unit performing a display based on detection information from the inertial sensor; and a mode changeover switch. The mode changeover switch changes a display mode of the display unit.

A sensor module that includes an inertial sensor and an abnormality determination unit that determines that the inertial sensor is abnormal when a structural resonance frequency at the first time point and a structural resonance frequency at the second time point are separated by a predetermined value or more.

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Shiojiri, Japan

Kenta Sato