414 results about "Triaxial accelerometer" patented technology

A highly miniaturized electronic data acquisition system includes MEMS sensors that can be embedded onto moving device without affecting the static/dynamic motion characteristics of the device. The basic inertial magnetic motion capture (IMMCAP) module consists of a 3D printed circuit board having MEMS sensors configured to provide a tri-axial accelerometer; a tri-axial gyroscope, and a tri-axial magnetometer all in communication with analog to digital converters to convert the analog motion data to digital data for determining classic inertial measurement and change in spatial orientation (rho, theta, phi) and linear translation (x, y, z) relative to a fixed external coordinate system as well as the initial spatial orientation relative to the know relationship of the earth magnetic and gravitational fields. The data stream from the IMMCAP modules will allow the reconstruction of the time series of the 6 degrees of freedom for each rigid axis associated with each independent IMMCAP module.

This invention relates to the use and proper placement in a vehicle of a mobile wireless phone having cellular or GPS positioning capability and an impact sensor, e.g. triaxial accelerometer. Said sensor instantly detects a serious vehicular accident or theft, then and without driver or passenger intervention, automatically transmits an emergency appeal for assistance to appropriate Police/Emergency Medical Services (PEMS), or Fire Rescue units, apprizing the PEMS of said exigency and location. Otherwise, the integrated mobile phone system will function in a manner that is similar to a conventional wireless mobile phone. Optionally, the integrated mobile wireless phone may include means for receiving an emergency medical signal and automatically communicates an appeal for emergency assistance when the user having said unit and having a predisposed life threatening medical condition, encounters a life threatening anomaly, e.g., heart attack. System provides means to mitigate multi-vehicle collisions that are normally associated with environmental road hazards fog, ice, etc., by instantly alerting authorities and/or drivers in the region of the location of said hazard when an accident occurs.

A compact navigation system for a rover is provided. The navigation system includes a housing configured to be transported by the rover; a gimbal system having two or more gimbals that includes at least an outer gimbal connected to the housing and an inner gimbal nested in and connected to the outer gimbal; a solid state three-axis gyro assembly mounted on the inner gimbal; a solid state three-axis accelerometer assembly mounted on the inner gimbal; a gyro logic circuit responsive to the three-axis gyro assembly for producing an inertial angular rate about each gyro input axis; an accelerometer logic circuit responsive to the three-axis accelerometer assembly for producing a non-gravitational acceleration along each accelerometer input axis; and a processor responsive to the gyro logic circuits and the accelerometer logic circuits for determining the attitude and the position of the housing to provide for long term accuracy of the attitude and the position for navigation of the rover.

A brain and/or skull impact measurement system has a body mounted impact device. The body mounted impact device includes a tri-axial accelerometer configured to measure impacts to an individual's body where the sensor produces impact data in response to the impact. A reader is provided with a data processor and a transmitter/receiver that receives the impact data. The reader is coupled to the body mounted impact device and can be a handheld device.

An attitude- and motion-sensing system for an electronic device, such as a cellular telephone, a game device, and the like, is disclosed. The system, which can be integrated into the portable electronic device, includes a two- or three-axis accelerometer and a three-axis magnetic compass. Data about the attitude of the electronic device from the accelerometer and magnetic compass are first processed by a signal processing unit that calculates attitude angles (pitch, roll, and yaw) and rotational angular velocities. These data are then translated into input signals for a specific application program associated with the electronic device.

Aspects of this invention include a rotary steerable steering tool having a sensor arrangement for measuring downhole dynamic conditions. Rotary steerable tools in accordance with this invention include a rotation rate measurement device disposed to measure a difference in rotation rates between a drive shaft and an outer, substantially non-rotating housing. A controller is configured to determine a stick/slip parameter from the rotation rate measurements. Exemplary embodiments may also optionally include a tri-axial accelerometer arrangement deployed in the housing for measuring lateral vibrations and bit bounce. Downhole measurement of stick/slip and other vibration components during drilling advantageously enables corrective measures to be implemented when dangerous dynamic conditions are encountered.

A directional tap detection algorithm and a single tri-axis accelerometer (10) are employed to extend the number of unique button less input commands available for a small mobile electronic device (12) such as a cell phone or a MP3 player. The algorithm analyzes acceleration data from the tri-axis accelerometer (10) to detect the direction and number of taps imparted to any of the six sides (14) of a housing (13) of the device (12), yielding 12 unique inputs. The algorithm employs a parameter referred to as the performance index (PI) to identify tap induced movements. The PI is determined by calculating the time derivative of each acceleration signal for each axis and then calculating the sum of the absolute values of the calculated acceleration derivatives. A tap is determined to have occurred if the sum exceeds a threshold value for a predetermined amount of time. If a second tap is detected within a predetermined time after the first tap, then a double tap is determined to have occurred.

An integrated calibration system and process for a three-axis (X, Y, Z) accelerometer estimates Z-axis bias, Z-axis bias drift and determines X, Y, and Z-axes error sources based on measurements taken when the accelerometer is static, i.e., sensing only the earth's gravitational acceleration. Optimal on-the-fly error estimates for the three-axis accelerometer are obtained so that the measurements provided by the three-axis accelerometer remain error-free.

In the present invention, a multi-person pose recognition system has been developed. This system includes a body pose detection module, a CC2420DBK board and a multi-person pose monitoring software module. The body pose detection module includes a triaxial accelerometer, a Zigbee chip and an 8-bit microcontroller. Several body pose detection modules and the CC2420DBK board form a Zigbee wireless sensor network (WSN). The CC2420DBK board functions as the receiver of the Zigbee WSN and communicates with a robot onboard computer or a host computer through a RS-232 port. The multi-person pose monitoring software monitors and records activities of multiple users simultaneously. The present invention provides a pose recognition algorithm by combining time-domain analysis and wavelet transform analysis. This algorithm has been implemented in the microcontroller of a body pose estimation module. Through the algorithm, the system can recognize seven body poses: falling, standing, sitting, lying, walking, going upstairs and going downstairs.

Method and apparatus of integrating a three-axis magnetometer and a three-axis accelerometer to provide attitude and heading, calibrated magnetometer and accelerometer data, and angular rate, while removing sensor error sources over time and temperature and to compensate for hard and soft iron distortions of the Earth magnetic field. Filtered accelerometer data are corrected to account for various error sources. The magnetic heading is calculated from a horizontal magnetic field vector transformed from three dimensional Earth's magnetic field vector by using quasi-static roll and pitch angles from the filtered accelerometer data. A first Kalman filter estimates the state vector, based on the principle that the magnitude of local Earth's magnetic field vector is constant, to form hard and soft iron correction matrices. A second Kalman filter estimates a correction matrix of coupled remaining soft iron and the misalignment of the magnetometer and the accelerometer, as the dot product of local Earth's magnetic field vector and a corrected gravitational acceleration vector, at a quasi-static position, is constant. The three dimensional Earth's magnetic field vector is received by removing the hard and soft irons through the soft iron and hard iron correction matrixes.

The invention provides a method of confirming motion parameters, an apparatus for the same, and a motion assisting device. The invention obtains and utilizes the motion data of a recognized object sampled at each of the sampling time, comprising the acceleration of the recognized object sampled by a tri-axial accelerometer, the angular velocity of the recognized object sampled by a tri-axial gyroscope, and the angle of the recognized object corresponding to a three-dimensional geomagnetic coordinate system sampled by a tri-axial magnetometer. Feedback calculation is utilized to obtain an actual acceleration at each sampling time from the motion original time to the motion end time, and the actual acceleration is obtained by reducing the acceleration of gravity from the acceleration sampled by a tri-axial accelerometer. The invention reduces the complexity of the system, and the accuracy is less affected by environmental factors, particularly light.

The invention discloses a detection device and a detection method for human motion information, belonging to the field of electronic information and mode identification. The detection device and the detection method of the human motion information are based on a single triaxial accelerometer and a Zigbee module; the detection method is based on a gait recognition technology and a statistical data modeling and can achieve detection of the human motion information by the triaxial accelerometer; the detection device comprises wireless sensing comprehensive modules arranged on a pair of shoes and an upper computer receiving module connected with a PC (Personal Computer) terminal; the device uses a trigger mode to perform wireless transmission for motion data in order to perform a human-computer interaction; due to a Zigbee low-power consumption design, a system can use batteries with smaller volume and capacity to reduce weight and volume of the whole system so as to be beneficial to be put at the bottom of the shoes; due to a voltage-stabilizing power supply design, an error of a quantized acceleration magnitude of an accelerometer after a working voltage drops can be avoided when the batteries are powered.

The invention provides a micro-electromechanical system (MEMS) triaxial accelerometer and a manufacturing method thereof. The MEMS triaxial accelerometer comprises a sensitive device layer, an upper cover board layer and a lower supporting body layer, wherein clearances are reserved between the sensitive device layer and the upper cover board layer as well as between the sensitive device layer and the lower supporting body layer; the sensitive device layer comprises a supporting frame body, an elastic beam, three independent sensitive mass blocks, movable comb teeth, fixed comb teeth and an electrode; the three independent sensitive mass blocks in the sensitive device layer are used for detecting acceleration signals of three axes X, Y and Z respectively; an acceleration sensor in each direction is hung in the supporting frame body through the corresponding sensitive mass block by the elastic beam which is only sensitive to the detection direction; a plurality of pairs of movable comb teeth are formed on each sensitive mass block by using a body silicon processing technology; a plurality of pairs of fixed comb teeth are correspondingly formed on the supporting frame body to form a pair of differential capacitors serving as sensitive capacitors; and the differential comb tooth capacitors in different directions generate a differential capacitance change in response to the acceleration signals in the corresponding directions.

The invention relates to a three-dimensional gesture determining and local positioning method of a lunar surface rover, which comprises the following steps: (1) ascertaining the rolling and pitching angles by use of a triaxial accelerometer with sensitivity while the rover is still; (2) determining the drift angle gesture by means of a sun sensor; (3) using the axial gesture and the gyro deviation as the state quantity, the rolling and pitching angles established by the triaxial accelerometer, the drift angle determined by the sun sensor as well as three gyro outputs as the measuring information, building a state equation and a measuring equation, and estimating the triaxial and gyro deviations by means of extended Kalman filter; (4) after compensating the gyro outputs by virtue of the estimated gyro deviations while the rover is in motion, calculating the gesture changes of the rover, finishing the preestimation of the gyro gesture, and fulfilling gesture update; (5) acquiring the information about the rotation speed of the driving wheels of the rover, the rotating angle of the steering wheel, the rotating angle of the left and right rocker arms, and getting the position increment of the rover in the body coordinate system by use of the forward kinematics relationship. The invention has the advantages of high precision of gesture determining and positioning, simple calculation and easy implementation of the engineering.

A method for calibrating a multiple-triad triaxial accelerometer is provided. The method may include receiving accelerometer measured output from a first measurement triad and at least one additional measurement triad of the accelerometer. The method may further include aligning the output of a x, y, and z components of the first measurement triad to be substantially orthogonal with respect to each other, aligning the output of x, y, and z components of at least one additional measurement triad to be substantially orthogonal with respect to each other, and rotating the output of at least one measurement triad so the outputs of all measurement triads substantially align with each other. The method may further include storing the result of the alignment and rotation associated with at least one calibration function associated with the multiple-triad triaxial accelerometer. The alignment and rotation may be performed substantially simultaneously.

Several micro-machined, ultra-profile two-axis and three-axis accelerometers are fabricated by CMOS-compatible process, which makes them suitable for volume production. The x, y axis signal is based on natural thermal convection, and z-axis signal may be based on thermal convention or piezoresistive in nature. The bulk MEMS (Micro-Electro-Mechanical-Systems) process is based on Deep Reactive Ion Etching (DRIE). After the front-end fabrication process, the accelerometers are packaged at wafer level by glass frit and/or anodic bonding, which lowers the device cost.

The invention relates to a human motion analytical method based on heart rate and an acceleration sensor and a device based on the method, which can detect the motion state of unobvious limb motions of weightlifting, strength training, yoga and the like. The human motion analytical method based on the heart rate and the acceleration sensor comprises the step that the motion state S is obtained by a triaxial accelerometer and a heart rate sensor. The data of the triaxial accelerometer and the data of the heart rate sensor are combined, cross comparison is carried out, various aerobic exercises and anaerobic exercises and sleep are effectively detected, results are more accurate, the condition that a product mistakenly prompts entering the motion state because of washing hands, folding up a quilt and other operation is effectively prevented, particularly when the product is used for judging the motion that the limbs do not move, such as the strength training, the yoga and the weightlifting, the condition is avoided, and the feedback used for stimulating a user to keep the state is provided.