1528 results about "Inertial measurement unit" patented technology

A pipeline inspection and defect mapping system includes a pig having an inertial measurement unit and a pipeline inspection unit for recording pig location and defect detection events, each record time-stamped by a highly precise onboard clock. The system also includes several magloggers at precisely known locations along the pipeline, each containing a fluxgate magnetometer for detecting the passage of the pig along the pipeline and further containing a highly precise clock synchronized with the clock in the pig. The locations of the various magloggers are known in a north/east/down coordinate system through a differential global positioning satellite process. Finally, a postprocessing off-line computer system receives downloaded maglogger, inertial measurement, and odometer data and through the use of several Kalman filters, derives the location of the detected defects in the north/east/down coordinate frame. Consequently, a task of identifying sites for repair activity is much simplified.

An interruption-free hand-held positioning method and system, carried by a person, includes an inertial measurement unit, a north finder, a velocity producer, a positioning assistant, a navigation processor, a wireless communication device, and a display device and map database. Output signals of the inertial measurement unit, the velocity producer, the positioning assistant, and the north finder are processed to obtain highly accurate position measurements of the person. The user's position information can be exchanged with other users through the wireless communication device, and the location and surrounding information can be displayed on the display device by accessing a map database with the person position information.

An improved fully-coupled vehicle positioning process and system thereof can substantially solve the problems encountered in global positioning system-only and inertial navigation system-only, such as loss of global positioning satellite signal, sensibility to jamming and spoofing, and inertial solution's drift over time, in which the velocity and acceleration from an inertial navigation processor are used to aid the code and carrier phase tracking of the global positioning system satellite signals, so as to enhance the performance of the global positioning and inertial integration system, even in heavy jamming and high dynamic environments. The improved fully-coupled GPS/IMU vehicle positioning system includes an IMU (inertial measurement unit) and a GPS processor which are connected to a central navigation processor to produce navigation solution that is output to an I/O (input/output) interface.

A system for allowing an operator to switch between remote vehicle tele-operation and one or more remote vehicle autonomous behaviors. The system comprises: an operator control unit receiving input from the operator including instructions for the remote vehicle to execute an autonomous behavior; a control system on the remote vehicle for receiving the instruction to execute an autonomous behavior from the operator control unit; and a GPS receiver, an inertial measurement unit, and a navigation CPU on the remote vehicle. Upon receiving the instruction to execute an autonomous behavior, the remote vehicle executes that autonomous behavior using input from the GPS receiver, the inertial measurement unit (IMU), and the navigation CPU.

A micro integrated Global Positioning System (GPS)/Inertial Measurement Unit (IMU) System, which is adapted to apply to output signals proportional to rotation and translational motion of a carrier and GPS measurements of the carrier, respectively from angular rate sensors, acceleration sensors, and GPS chipset, is employed with MEMS angular rate and acceleration sensors and GPS chipset. Compared with a conventional IMU/GPS system, the system of the present invention uses an integrated processing scheme by means of digital closed loop control of the dither driver signals for MEMS angular rate sensors, a feedforward open-loop signal processing scheme of the IMU, digital temperature control and compensation, the earth's magnetic field-based heading damping, robust error estimator, and compact sensor and circuit architecture and dramatically shrinks the size of mechanical and electronic hardware and power consumption, meanwhile, obtains highly accurate motion measurements.

An interruption free navigator includes an inertial measurement unit, a north finder, a velocity producer, a positioning assistant, a navigation processor, an altitude measurement, an object detection system, a wireless communication device, and a display device and map database. Output signals of the inertial measurement unit, the velocity producer, the positioning assistant, the altitude measurement, the object detection system, and the north finder are processed to obtain highly accurate position measurements of the person. The user's position information can be exchanged with other users through the wireless communication device, and the location and surrounding information can be displayed on the display device by accessing a map database with the person position information.

A real-time integrated vehicle positioning method and system with differential GPS can substantially solve the problems encountered in either the global positioning system-only or the inertial navigation system-only, such as loss of global positioning satellite signal, sensitivity to jamming and spoofing, and an inertial solution's drift over time. In the present invention, the velocity and acceleration from an inertial navigation processor of the integrated GPS/INS system are used to aid the code and carrier phase tracking of the global positioning system satellite signals, so as to enhance the performance of the global positioning and inertial integration system, even in heavy jamming and high dynamic environments. To improve the accuracy of the integrated GPS/INS navigation system, phase measurements are used and the idea of the differential GPS is employed. However, integer ambiguities have to be resolved for high accuracy positioning. Therefore, in the present invention a new on-the-fly ambiguity resolution technique is disclosed to resolve double difference integer ambiguities. The real-time fully-coupled GPS/IMU vehicle positioning system includes an IMU (inertial measurement unit), a GPS processor, and a data link which are connected to a central navigation processor to produce a navigation solution that is output to an I/O (input/output) interface.

A system and method for efficiently locating in 3D an object of interest in a target scene using video information captured by a plurality of cameras. The system and method provide for multi-camera visual odometry wherein pose estimates are generated for each camera by all of the cameras in the multi-camera configuration. Furthermore, the system and method can locate and identify salient landmarks in the target scene using any of the cameras in the multi-camera configuration and compare the identified landmark against a database of previously identified landmarks. In addition, the system and method provide for the integration of video-based pose estimations with position measurement data captured by one or more secondary measurement sensors, such as, for example, Inertial Measurement Units (IMUs) and Global Positioning System (GPS) units.

A method and apparatus for providing three-dimensional navigation for a node comprising an inertial measurement unit for providing gyroscope, acceleration and velocity information (collectively IMU information); a ranging unit for providing distance information relative to at least one reference node; at least one visual sensor for providing images of an environment surrounding the node; a preprocessor, coupled to the inertial measurement unit, the ranging unit and the plurality of visual sensors, for generating error states for the IMU information, the distance information and the images; and an error-state predictive filter, coupled to the preprocessor, for processing the error states to produce a three-dimensional pose of the node.

In one embodiment of the present invention, a method of and apparatus for determining inaccurate GPS samples in a set of GPS samples is disclosed, according to the following actions: a) obtaining GPS samples as taken by a global positioning system on board a vehicle when traveling along a trajectory; b) obtaining a first estimation of the trajectory based on the GPS samples; c) obtaining a second estimation of the trajectory at least based on measurements made by an inertial measurement unit on board vehicle when traveling along the trajectory; d) comparing the first and second estimations; e) establishing locations where the first estimation shows a variation compared with the second estimation above a predetermined threshold; f) if no such locations can be established continue with action j), otherwise continue with action g); g) removing GPS samples associated with the locations of high variation as being inaccurate GPS samples, thus forming a set of remaining GPS samples; h) calculating the first estimation anew of the trajectory based on the remaining GPS samples and calculating the second estimation anew; i) repeating actions d) to h); j) ending the actions.

A receiver for continuous carrier phase tracking of low carrier-to-noise ratio (“CNR”) signals from a plurality of radio navigation satellites while the receiver is mobile. The receiver may have: a radio frequency (RF) front-end that provides satellite data corresponding to signals received from the plurality of radio navigation satellites; an inertial measurement unit (IMU) that provides inertial data; and a processor circuit in circuit communication with the RF front end and the IMU, the processor circuit being capable of using satellite data from the RF front-end and inertial data from the IMU to perform continuous carrier phase tracking of low CNR radio navigation satellite signals having a CNR of about 20 dB-Hz, while the receiver is mobile. The receiver may be a GPS receiver for continuous carrier phase tracking of low-CNR GPS signals.

A virtual reality (VR) console receives slow calibration data from an imaging device and fast calibration data from an inertial measurement unit on a VR headset including a front and a rear rigid body. The slow calibration data includes an image where only the locators on the rear rigid body are visible. An observed position is determined from the slow calibration data and a predicted position is determined from the fast calibration data. If a difference between the observed position and the predicted position is greater than a threshold value, the predicted position is adjusted by a temporary offset until the difference is less than the threshold value. The temporary offset is removed by re-calibrating the rear rigid body to the front rigid body once locators on both the front and rear rigid body are visible in an image in the slow calibration data.

Vehicle-mounted device includes an inertial measurement unit (IMU) having at least one accelerometer or gyroscope, a GPS receiver, a camera positioned to obtain unobstructed images of an area exterior of the vehicle and a control system coupled to these components. The control system re-calibrates each accelerometer or gyroscope using signals obtained by the GPS receiver, and derives information about objects in the images obtained by the camera and location of the objects based on data from the IMU and GPS receiver. A communication system communicates the information derived by the control system to a location separate and apart from the vehicle. The control system includes a processor that provides a location of the camera and a direction in which the camera is imaging based on data from the IMU corrected based on data from the GPS receiver, for use in creating the map database.

A GNSS integrated multi-sensor guidance system for a vehicle assembly includes a suite of sensor units, including a global navigation satellite system (GNSS) sensor unit comprising a receiver and an antenna. An inertial measurement unit (IMU) outputs vehicle dynamic information for combining with the output of the GNSS unit. A controller with a processor receives the outputs of the sensor suite and computes steering solutions, which are utilized by vehicle actuators, including an automatic steering control unit connected to the vehicle steering for guiding the vehicle. The processor is programmed to define multiple behavior-based automatons comprising self-operating entities in the guidance system, which perform respective behaviors using data output from one or more sensor units for achieving the behaviors. A GNSS integrated multi-sensor vehicle guidance method is also disclosed.

A Micro Inertial Measurement Unit (IMU) which is based on MEMS accelerometers and gyro sensors is developed for real-time recognition of human hand motions, especially as used in the context of writing on a surface. Motion is recorded by a rate gyro and an accellerometer and communicated to a Bluetooth module, possibly to a computer which may be 20 to 30 feet or more from the sensor. The motion information generated and communicated is combined with appropriate filtering and transformation algorithms to facilitate a complete Digital Writing System that can be used to record handwriting on any surface, or on no surface at all. The overall size of an IMU can be less than 26 mm×20 mm×20 mm, and may include micro sensors, a processor, and wireless interface components. The Kalman filtering algorithm is preferably used to filter the noise of sensors to allow successful transformance of hand motions into recognizable and recordable English characters. The immediate advantage is the facilitation of a digital interface with both PC and mobile computing devices and perhaps to enable wireless sensing.

A handheld stabilizer for automatically stabilizing a camera device, such as a smartphone, when the camera device is mounted on the stabilizer is provided. The stabilizer comprises a camera device mount for holding the camera device, a plurality of motors collectively arranged to cause the camera device mount to be rotatable about three predetermined substantially-orthogonal axes, an inertial-measurement unit (IMU) sensor for measuring an angle and an angular velocity experienced by the camera device about each of the three axes, and a controller. By means of the IMU sensor, an attitude of the camera device is measured. The controller is configured to estimate an attitude error of the camera device according to the measured attitude, and to automatically control the plurality of motors in response to the attitude error so as to controllably rotate the camera device about each of the three axes to counter the attitude error.

Disclosed are method and apparatus for controlling the blade elevation and blade slope angle of a dozer blade. Elevation and slope angle measurements are calculated from measurements received from a global navigation satellite system (GNSS) antenna and an inertial measurement unit mounted on the dozer blade. The inertial measurement unit includes three orthogonally placed accelerometers and three orthogonally placed rate gyros. The measurements are processed by algorithms to calculate estimates of the blade elevation, blade vertical velocity, blade slope angle, and blade slope angular velocity. These estimates are then provided as inputs to a control algorithm which provides control signals to control a dozer hydraulic system which controls the blade elevation and blade slope angle.

The invention relates to the technical field of four-rotor aircrafts, in particular to a small four-rotor aircraft control system and method based on an airborne sensor. The small four-rotor aircraft control system based on the airborne sensor comprises an inertia measurement unit module, a microprocessor, an electronic speed controller, an ultrasonic sensor, an optical flow sensor, a camera, a wireless module and a DC brushless motor. By merging the information of a light and low-cost airborne sensor system, the six-DOF flight attitude of the aircraft is estimated in real time, and a closed-loop control strategy comprising inner-loop attitude control and outer-ring position control is designed. Under the environment without a GPS or an indoor positioning system, flight path control and aircraft formation control based on the leader followed strategy over the rotorcraft are achieved through the airborne sensor system and the microprocessor, wherein the flight path control comprises autonomous vertical take-off and landing, indoor accurate positioning, autonomous hovering and autonomous flight path point tracking. According to the small four-rotor aircraft control system and method, a reliable, accurate and low-cost control strategy is provided for achieving autonomous flight of the rotorcraft.

The invention relates to a navigating and stabilized sighting method of a navigation/stabilized sight all-in-one system, belonging to the inertial guidance field. The navigating method realizes stance and positioning on a load by an inertial measuring unit which is arranged on an electro-optical stabilized sighting platform. The method comprises the steps as follows: collecting the signal of the inertial measuring unit; fast and accurately initial aligning below the stabilized sighting platform; an inertial navigation algorithm based on vehicle-bone stabilized sighting platform; resolving heading attitude and analyzing the error thereof; analyzing the error of an inertial guidance system and an inertial part, modeling and compensating; and inertial guidance/milemeter/GPS multi-information fault-tolerance combined navigation. The navigation method overcomes the defects in the prior art that stabilized sighting and the navigation system can not work simultaneously and the all-in-one system can not provide full navigation information, can provide real-time, accurate and complete navigation heading attitude information and navigation positioning information for carriers (like a chariot), and can improve the battlefield viability and the comprehensive hosting ability.

A MEM inertial sensor (e.g. accelerometer, gyroscope) having integral rotational means for providing static and dynamic bias compensation is disclosed. A bias compensated MEM inertial sensor is described comprising a MEM inertial sense element disposed on a rotatable MEM stage. A MEM actuator for drives the rotation of the stage between at least two predetermined rotational positions. Measuring and comparing the output of the MEM inertial sensor in the at least two rotational positions allows, for both static and dynamic bias compensation in inertial calculations based on the sensor's output. An inertial measurement unit (IMU) comprising a plurality of independently rotatable MEM inertial sensors and methods for making bias compensated inertial measurements are disclosed.

In one preferred embodiment, the present invention provide a navigation system for a movable platform comprising a GNSS receiver sensor for providing position signals representative of the estimated current position of the movable platform; a camera sensor for providing photographic images representative of the surroundings of the movable platform; and an IMU (Inertial Measurement Unit) sensor for providing specific force and angular rate signals representative of the current specific forces and rate of the movable platform. A processor is responsive to the camera photographic images to estimate the position and attitude of the movable platform, the covariance of the position and attitude estimates and the covariance of consecutive position and attitude estimates. The processor is responsive to the GNSS receiver's estimated position signal, the camera's estimated position and attitude signal, the camera's estimated position and attitude covariance, the camera's estimated correlation of the covariance of consecutive position and attitude estimates, and the specific force and angular rate signals, for providing a navigation solution representative of the estimated current position, velocity, and attitude of the movable platform.

The invention discloses intelligent glasses and a method for monitoring movement, preventing shortsightedness and correcting sitting postures by utilizing the same. The intelligent glasses comprise a glasses frame, and an inertial sensor, a data processing module, an alarm display module and a power module which are arranged in the glasses frame; the inertial sensor, the alarm display module and the power module are all connected with the data processing module electrically; the inertial sensor adopts an accelerometer, or an angular velocity sensor, or an inertia measurement unit with single, double or three shaft combination of the accelerometer or the angular velocity sensor, or a navigation position reference system. The intelligent glasses are simple in structure, comprehensive in functions and good in ductility; by full-featured accurate detection on multiple factors influencing vision, including postures in two directions of the head of a user, viewing distance, viewing time and various lighting conditions, the eye health of the user under various conditions is ensured.

Described are computer-based methods and apparatuses, including computer program products, for inertially tracked objects with a kinematic coupling. A tracked pose of a first inertial measurement unit (IMU) is determined, wherein the first IMU is mounted to a first object. The tracked pose of the first IMU is reset while the first object is in a first reproducible reference pose with a second object.

An apparatus for providing three-dimensional pose comprising monocular visual sensors for providing images of an environment surrounding the apparatus, an inertial measurement unit (IMU) for providing gyroscope, acceleration and velocity information, collectively IMU information, a feature tracking module for generating feature tracking information for the images, and an error-state filter, coupled to the feature track module, the IMU and the one or more visual sensors, for correcting IMU information and producing a pose estimation based on at least one error-state model chosen according to the sensed images, the IMU information and the feature tracking information.

A coupled real time emulation method for positioning and location system includes the steps of receiving real time trajectory data from a 6DOF trajectory generator and generating global positioning system simulated measurements and inertial measurement unit simulated electronic signals which are injected into an on-board integrated global positioning system/inertial measurement unit system. When the on-board integrated global positioning system/inertial measurement unit system is excited in dynamic operation, a performance thereof is able to be tested and evaluated as if carrying a real transportation test.

An apparatus for analyzing movement of equipment. The apparatus includes an inertial measurement unit continuously measuring six rigid body degrees of freedom of the equipment and outputting data representative thereof, wherein the inertial measurement unit defines a planar substrate having a single common plane. The inertial measurement unit further includes at least one angular rate gyro and at least one accelerometer sufficient to measure the six rigid body degrees of freedom and each being mounted on the single common plane. The apparatus further includes a processing unit determining the acceleration of the mass center of the equipment, the angular velocity and the angular acceleration of the equipment through a single derivative operation.

A method for processing data in an inertial navigation system having a Kalman filter and computer-readable storage medium containing instructions to configure a processor to perform the same. The method produces more accurate estimates of the position, velocity and attitude of the inertial measurement unit. The method is fully automatic and enables zero-velocity updates and fixed-azimuth updates to be performed simultaneously. The method may also include a multi-stage filtering process to filter digital compass data when used in an environment with extraterrestrial magnetic field sources. The method may also include a fixed-lag smoother to improve estimates of the position, velocity and attitude of the inertial measurement unit. The method also may include processes to constrain altitude errors.

The invention relates to the technical field of mobile robot autonomous navigation and particularly relates to an omnidirectional mobile robot autonomous navigation apparatus and method based on a laser range finder. The omnidirectional mobile robot autonomous navigation apparatus based on the laser range finder comprises an encoder for measuring the movement distance of wheels of a mobile robot, and an inertia measurement unit for measuring the rotation angular velocity and the acceleration of the mobile robot. The encoder and the inertia measurement unit are connected with a controller. The omnidirectional mobile robot autonomous navigation apparatus also comprises the laser ranger finder which is connected with a host computer. The host computer is connected with the controller, and the controller is connected with an execution unit. The invention utilizes the laser range finder to position the mobile robot, establishes a two-dimensional planar map of the environment, carries out autonomous navigation according to a target task, and achieves autonomous obstacle avoidance in the movement.

The invention provides an unmanned aerial vehicle bridge bottom surface crack detection method and system. The unmanned aerial vehicle bridge bottom surface crack detection system comprises an unmanned aerial vehicle end and a ground workstation. The unmanned aerial vehicle end utilizes an airborne laser radar and an inertial measurement unit to position an unmanned aerial vehicle and form an unmanned aerial vehicle peripheral barrier point cloud to avoid barriers and plan a path; and an airborne platform camera photographs a bridge bottom surface at a constant frequency and stores a high-definition image into a memory. The ground workstation processes the photographed image, and splices an image between bridge piers to form a large-sized bridge bottom surface image; then the edge information in the image is acquired, the morphological corrosive expansion and connection are performed on the edge to extract a complete crack, and the crack is roughly positioned by virtue of a bridge pier position at which the spliced image is arranged; and finally the crack is evaluated, and information about the crack such as a length, a width, a distribution density and the like is analyzed and measured. The unmanned aerial vehicle bridge bottom surface crack detection method and system are high in automation degree, high in efficiency, high in safety coefficient, low in cost and wide in application prospect on the aspect of the bridge bottom surface route inspection.

A percussion controller comprises an instrumented striker including devices for obtaining inertial measurements and a wireless transmitter, a sensor-enabled striking surface that receives an impact from the instrumented striker, and a data processing system that receives the inertial measurements and predicts at least one of the force or location of impact of the instrumented striker on the sensor-enabled striking surface before impact actually occurs.