173 results about "Frame of reference" patented technology

The invention discloses a method for improving the performance of double-independent quantum key distribution of actual reference system measurement equipment, belongs to the technical field of quantum key distribution (QKD), and aims to improve the performance of the double-independent quantum key distribution when non-ideal factors such as a post-pulse effect of a detector and finite sample statistical fluctuation are considered. The invention relates to a method and a system for improving the performance of a reference system measurement device by introducing an advantage extraction technology into a double independent quantum key distribution (RFI-MDI-QKD) protocol of the reference system measurement device. Simulation results show that when the post-pulse effect and the statistical fluctuation effect are considered, the advantage extraction method can effectively improve the security key rate and the security transmission distance of the RFI-MDI-QKD protocol on the premise of not changing optical hardware. According to the invention, a valuable reference technology can be provided for practical research of the RFI-MDI-QKD system.

Methods and apparatus for providing self-contained guidance, navigation, and control (GN&C) functions for a vehicle moving through an environment on or near the ground, in the air or in space without externally provided information are disclosed. More particularly, one embodiment of the present invention includes a Heading Sensor (36), an Absolute Location Sensor (38), a timer (40), a Range Doppler Processor (42), a Navigation Reference Sensor (44), an Area Range and a Velocity Sensor (46) which provide enhanced navigation information about a universal reference frame (22) and one or more targets (20).

Methods and apparatus for providing self-contained guidance, navigation, and control (GN&C) functions for a vehicle moving through an environment on or near the ground, in the air or in space without externally provided information are disclosed. More particularly, one embodiment of the present invention includes a Heading Sensor (36), an Absolute Location Sensor (38), a timer (40), a Range Doppler Processor (42), a Navigation Reference Sensor (44), an Area Range and a Velocity Sensor (46) which provide enhanced navigation information about a universal reference frame (22) and one or more targets (20).

The invention relates to the technical field of water ecological environment remote sensing monitoring, in particular to a river total nitrogen concentration remote sensing estimation method based on multi-source data fusion, and the method comprises the following steps: S1, obtaining and processing total nitrogen measured data, and unifying time and a coordinate reference system; s2, processing the Landsat 8 / 9 image, and extracting water body reflectivity and remote sensing indexes; s3, ERA5-Land meteorological data are acquired, and derivation indexes are calculated; s4, DEM elevation data are extracted; s5, fusing the multi-source data to generate a table type data set; s6, screening sensitive indexes based on SHAP and correlation; s7, constructing and evaluating an inversion model; s8, extracting an MNDWI water body mask; s9, generating a feature stack and inverting and outputting a total nitrogen concentration diagram; according to the method, through fusion of multi-source data, construction of a high-precision inversion model and a cloud platform automatic processing flow, high-temporal-spatial-resolution, stable and reproducible remote sensing estimation of the total nitrogen concentration of the river is realized, and the monitoring efficiency and the application value are effectively improved.

The invention relates to the technical field of inertial navigation, in particular to an inertial navigation data correction method based on a neural network, which comprises the following steps: firstly, collecting original data of an inertial measurement unit and preprocessing; secondly, generating an attitude error label by using a high-precision reference system, and constructing a training data set containing historical time sequence information in a sliding window mode; then constructing a hybrid neural network model, and performing iterative training by using the training data set; and finally, in real-time navigation, obtaining an inertial data sequence at the current moment by maintaining a historical data buffer area, inputting a trained model to predict an error compensation value, correcting an original calculation attitude, and outputting the corrected original calculation attitude. The method gets rid of dependence on an accurate physical model through a data driving mode, utilizes the hybrid neural network to deeply mine time sequence accumulation characteristics of inertial data, realizes long-endurance high-precision autonomous navigation, and remarkably inhibits divergence of attitude errors.

One example provides a laser measurement system comprising an alignment artifact attached to a global reference frame. The alignment artifact has features that define corresponding reference points. A controller is configured to obtain metadata comprising expected locations of the corresponding reference points for the features within a target view during a scan. The controller is also configured to obtain a raw point cloud of the alignment artifact within a scanner reference frame. The controller is further configured to determine scanned features from the raw point cloud, and locations of corresponding scanned reference points to form a set of scanned locations. The controller is also configured to determine a transformation matrix to transform coordinates between the scanner reference frame and the global reference frame based at least upon the set of expected locations, the set of scanned locations, and a common direction vector for a plurality of laser line scanners.

The invention discloses a self-adaptive federated Kalman filtering method based on detectability and information entropy, which is characterized by comprising the following steps of: firstly, constructing a multi-source navigation system comprising an INS (Inertial Navigation System), a DVL (Digital Video Library) and a USBL (Universal Serial Bus Library); the INS is used as a global reference system of the multi-source navigation system; a plurality of first sub-filters and second sub-filters are respectively arranged in the DVL and the USBL; then, establishing a DVL error measurement equation of the first sub-filter and a USBL error measurement equation of the second sub-filter, and calculating a detectability quantitative index and a comprehensive information entropy of the sub-filters; calculating an information distribution factor of each sub-filter based on the detectability quantitative index and the comprehensive information entropy; and based on the information distribution factors, a main filter of the multi-source navigation system performs state estimation of each sub-filter and weighted fusion of covariance, and outputs navigation information. According to the method, the influence degree of each sub-filter on the output navigation information can be dynamically adjusted through the information distribution factors, and the precision and fault tolerance of autonomous navigation of the system are improved.

Disclosed are systems and methods for motor control using optimal efficiency reference generation. An electronic controller can determine current values of a motor in a rotating reference frame. Each current value can be associated with a dimension of a set of dimensions of the rotating reference frame. The electronic controller can further determine flux linkage values for each dimension of the set of dimensions of the rotating reference frame based on the current values using an optimization cost function that accounts for motor speed, copper loss, and core loss. The electronic controller can further determine target flux linkage values for each dimension of the set of dimensions of the rotating reference frame. The electronic controller can then control a power switch network coupled between a power source and the motor based on the flux linkage values and the target flux linkage values.

This invention relates to the field of intelligent monitoring technology, and discloses an intelligent monitoring system and method for injection molding processes using injection molds. The system includes: acquiring synchronous operation signals from mold opening to the ejection window, mapping their time series to an ejection relative stroke reference system constructed based on the ejector plate displacement; calculating the deflection resistance trajectory bending degree based on the normalized derivative transformation of the extracted force relative to the relative stroke reference system; extracting morphological parameters and demolding work offset, and combining them to construct a state vector; constructing a classification space using a reference sample library, and optimizing a preset classifier using a particle swarm optimization algorithm; inputting the state vector to be measured into the classifier to output the continuous anomaly probability and the abnormal fluctuation work amount; and finally calculating the work concentration point and mapping it to the corresponding mold condition node. This invention can overcome the limitations of the time domain and rigid thresholds, identify abnormal demolding actions within a very short window early, and achieve precise positioning.

The invention provides a spacecraft attitude orbit navigation initial value on-orbit establishment method and device, and belongs to the technical field of spacecraft navigation.The method comprises the steps that a navigation system single-machine product configuration scheme and a single-machine installation layout scheme are designed; judging whether the platform is successfully separated from the mother platform or not; the self angular rate is damped; performing slow rotation search around two axes of the body, and preliminarily establishing an inertial system attitude initial value; carrying out slow rotation search around two axes of the body, and preliminarily establishing an initial speed value of the earth fixed connection position; performing attitude maneuver based on the inertial system attitude initial value and the earth fixed connection system position speed initial value, and adjusting the attitude to a final stable direction capable of capturing the attitude and the position speed at the same time; and according to the attitude and position speed result, calculating the position speed and attitude result under the expected reference system as a final inertial navigation initial value. According to the invention, a software and hardware interface for information transmission does not need to be arranged between the spacecraft and the release mother platform, and the capability of on-orbit self-establishment of inertial navigation attitude and position speed initial values is realized.

Video coding using warped motion compensation is described. Extended rotations for the warped motion compensation can be explicitly signaled. For example, motion parameters for predicting the current block and a rotation angle can be decoded. A warping matrix is obtained using the motion parameters and the rotation angle, and a prediction block is obtained by projecting the current block to a quadrilateral in a reference frame. Also described is determining a prediction model of the current block and obtaining a prediction block by projecting the current block to a quadrilateral in a reference frame. Determining the prediction model can include determining whether to predict the current block using a motion vector, a local warping model, or a global motion model, obtaining motion parameters of the prediction model, decoding a rotation angle, and obtaining a warping matrix using the motion parameters and the rotation angle.

The invention relates to a device for reflecting daylight in a fixed direction chosen by the user, despite the sun's movement. The device is distinguished by its ability to be placed in any position and requires no calibration by the user. It positions itself in the Earth's frame of reference using an accelerometer coupled to a solar sighting system, which allows it to determine its position in the Earth's frame of reference and orient the mirror to maintain a constant direction of the reflected beam. The beam is unaffected by any cast shadows, and the system's accuracy is increased compared to compass-based devices. (Shorthand figure: Figure 1)

The invention belongs to the technical field of navigation, and discloses a navigation positioning method based on multi-source data fusion, which comprises the following steps: an error equation of an inertial navigation system is calculated, and a system state equation is the error equation of the inertial navigation system and mainly comprises attitude, speed, position and inertial device error equations; and calculating an inertia / TACAN state equation. Filtering state fusion estimation is calculated, an inertial navigation system serves as a reference system, other satellite navigation systems and the inertial navigation system form a sub-filter, state estimation is conducted through Kalman filtering, and then a filtering result is sent to a main filter for information fusion. Through the steps, the influence of a single navigation system on the airborne navigation system is effectively reduced, and the reliability of the navigation system in a complex electromagnetic environment is improved.

Systems and methods for forming a patient tracker for detecting movement are provided. The patient tracker comprises a reference frame positioned on a patient; and at least one marker positioned on the patient and spaced from the reference frame, wherein the reference frame and the at least one marker are registered using an X-ray imaging device, and wherein a location of the patient tracker is defined based on the registration of the reference frame and the at least one marker. The registration of the reference frame and the at least one marker may be based on one or more images obtained from the X-ray imaging device. The reference frame may include at least four markers.

The invention discloses a geological map scene implementation method and system based on measure potential tapping, relates to the technical field of oil and gas field development, and is used for solving the problems that conflicts among a caliber layer, a method layer and a data layer are accurately positioned based on the same reference system, and a minimum recalculation set is difficult to stably solve according to the conflicts. Establishing a strong primary key index of a well ID, a layer ID, a grid unit and a time step, and registering and generating a caliber; a bidirectional Hausdorff distance is minimized through a multi-resolution pyramid and elastic registration, isolines are extracted and vectorized into a boundary set, scale factors and registration evidences are recorded, and co-located grids are generated; calculating four components including space overlapping, boundary consistency, trend correlation and abnormal co-location of CI in co-location grids, and performing structured output; and forming a conflict graph, locally replaying and generating a factor importance sequence by using a single factor, and solving a minimum recalculation set.

Title: Methods and devices for encoding and decoding a time sequence of multidimensional scenes and corresponding computer program. The invention relates to a method for encoding at least one scene of a time sequence of multidimensional scenes, implementing: a selection (11), in a reference frame, of an object corresponding to a current object, a determination (12) of at least one difference between at least one descriptive piece of information of said selected object and of said current object, an ordering (13) of said selected objects in an ordered predictor list and of said associated differences in an ordered corrector list, a construction (14) of a list of actions, an encoding (15) of at least one action from said action list and of at least one difference from said ordered corrector list. Figure for the abstract: Figure 1

A plurality of scattered laser pulses is received, each scattered laser pulse associated with at least one plurality of respective dwells. A set of 3D velocity information is received, which is derived from photo events detected in information associated with the received plurality of scattered laser pulses. Each dwell in the plurality of dwells is associated with one or more photo events. The 3D velocity information includes information estimating each respective photo event's respective position in 6D space during the respective dwell associated with the photo event. For each dwell, its respective photo events are projected into a common reference frame, determined based on the 3D velocity information, to generate a set of motion-compensated point clouds. Each respective motion-compensated point cloud, for each dwell, is registered to the other motion-compensated point clouds in the set, to generate a set of registered point clouds, which are merged into a volumetric image.

A robotic navigation system includes a robot base; a robotic arm comprising a proximal portion secured to the robot base, a distal portion movable relative to the proximal portion, and a tracking marker secured to the robotic arm proximate the distal portion; at least one processor; a navigation system including a tracking marker sensor configured to identify positions of the tracking marker in a first coordinate space; and a memory. The memory stores instructions that cause the at least one processor to: cause the robotic arm to move to a plurality of different poses; receive information relating to a position of the tracking marker in a second coordinate space when the robotic arm is in each of the plurality of different poses; and compare the positions of the tracking marker in the first coordinate space to the positions of the tracking marker in the second coordinate space.

A medical device visualization system includes a stylet, a plurality of patient-wearable sensors, and a console. The stylet includes an optical fiber with a plurality of sensors distributed along a length thereof, and a field generator in a distal tip. The plurality of patient-wearable sensors are configured to sense a field generated by the field generator. The console is configured for visualizing the stylet as it is advanced in a patient. A visualization process can include a shape-sensing process, a registration process, and a reference-framing process. The shape-sensing process can utilize shape-sensing logic for determining a shape of the stylet in real-time from reflected optical signals reflected by the plurality of sensors. The registration process can utilize registration logic for registering the distal tip of the stylet. The reference-framing process can utilize reference-framing logic for placing the stylet in a reference frame.

The present application relates to machine vision, in particular to a cross-camera target alignment and deduplication counting method based on timing consistency, obtaining a video stream of a camera, establishing a unified time reference system; independently executing target detection and tracking algorithms in each camera, and generating a local trajectory for each target; generating a candidate trajectory pair set according to the number of consecutive tracking frames of the target in a single camera and the time window of the trajectory appearing in different cameras; calculating a matching score for each candidate trajectory pair based on motion behavior consistency; globally optimizing and conflict resolving all candidate trajectory pairs, and outputting a cross-camera associated trajectory pair set; merging the corresponding cross-camera associated trajectory pairs into the same target by using an uncertainty quantification mechanism, directly performing deduplication counting, and simultaneously performing uncertainty marking; the present application can overcome the defect that accurate cross-camera target alignment and deduplication counting cannot be performed in an industrial conveyor belt scene with dynamic characteristics.

A video may be framed using information on the direction of gravity and the direction of north with respect to an image capture device during video capture, information on changes in the orientation of the image capture device during video capture, and information on the direction of motion of the image capture device during video capture. The changes in the orientation of the image capture device may be in an image capture device reference frame, and the direction of motion of the image capture device may be in the earth reference frame. The changes in the orientation of the image capture device and the direction of motion of the image capture device may be merged into a single reference frame using the direction of gravity and the direction of north with respect to the image capture device, and the video may be framed in the single reference frame to include the extents of the video in the direction of the motion of the image capture device during video capture.

The invention relates to a method (20) for generating a three-dimensional scene, comprising the steps:for each of at least one previously selected 3D object:placing (26) said 3D object in a three-dimensional reference frame, said 3D object being aligned with an active support surface of the three-dimensional scene, each active support surface being a support surface orthogonal to a director vector of an altitude axis of the virtual three-dimensional reference frame, to within a predetermined angular tolerance;updating an occupancy map of active support surfaces;for each collision detected between 3D objects in the virtual three-dimensional reference frame, implementing a correction (28) comprising a movement of at least one 3D object affected by said collision based on the occupancy map.

System and method for detecting, tracking, and projecting the trajectory of an object. The invention relates primarily to a system for detecting and tracking the trajectory of an object moving in a public or private space, comprising computer means configured to determine the coordinates of the object's trajectory in an image frame, transpose these coordinates into the camera frame and then into the Earth's reference frame, and project the object's trajectory onto a plane bounded by two axes of the Earth's reference frame corresponding to the ground of the location. Figure to be published with the abstract: Fig. 1

The present invention relates to a device (1) for loading generally parallelepiped-shaped flat elements (30) having four corners (300), an upper face (31) and a lower face (32), said elements (30) being stacked in the form of a pile (3), the loading being carried out by a successive transfer from said pile (3) to a processing station (2), said processing station (2) having an inlet (20) for receiving the successive elements (30), optionally held by a link (90) or similar to form a batch, said device (1) comprising at least: - a gripping tool (4) adapted for lifting and moving said flat elements (30) from the pile (3) to the inlet (20), said gripping tool (4) comprising at least one gripping member (40), - a control unit (5) configured to execute a routine for loading said inlet (20) of said processing station (2) from the pile (3) of (30) flat elements,- a robotic arm (6) designed and arranged to move said gripping tool (4) at least between the stack (3) and the inlet (20) of the station (2), said tool (4) being positioned at the distal end of said robotic arm (6), the device (1) being characterized in that it comprises: - optical detection means (7), said means (7) comprising at least one camera (70) enabling the detection, for each flat element (30) to be moved by said gripping tool (4), of at least one marker (8), said marker (8) being located on one of the faces (31, 32) of said element (30),and in that - the control unit (5) is configured to determine and / or receive coordinates of said at least one detected reference frame (8) and to transmit instructions to control means (60) of an actuator of said robotic arm (6) in order to adjust the displacement of said gripping tool (4) according to the coordinates of said at least one reference frame (8). The invention also relates to a loading method and an element (30) comprising at least one reference frame (8) on one of its faces (31, 32). Figure for the abstract: Fig. 2,

A method comprises providing a vehicle landing pad with a reference frame origin at a center thereof, and X and Y axes through the reference frame origin; arranging a first group of markers, each having a first size, on the pad such that the first group of markers form a first convex hull about the center of the pad; and arranging a second group of markers, each having a second size less than the first size, on the pad such that the second group of markers form a second convex hull within the first convex hull. The first and second groups of markers are located symmetrically with respect to the center of the pad along the X and Y axes so as to yield a position estimation solution for landing a vehicle having a highest accuracy when compared with placing markers at other locations along the X and Y axes.

A system and method of tracking a flexible elongate instrument within a patient is disclosed herein. The system is configured to obtain remote localization measurement data of the flexible elongate instrument and obtain elongation measurement data of the flexible elongate instrument. This data is combined and transformed to a coordinate reference frame to produce a localization of the flexible elongate instrument that is more accurate than the remote localization measurements or elongation measurement data alone. The combined localization is then provided to a localization consumer.

Methods, non-transitory computer readable media, and surgical computing devices that more effectively protect anatomical structures from resection during surgical procedures are disclosed. With this technology, a virtual protection area is defined in a reference frame by extending a line defined by an obtained set of coordinates in the reference frame in at least one direction. The reference frame is of a bone to be resected during a surgical procedure. Resection equipment is tracked during the surgical procedure to obtain a location of the resection equipment in the reference frame. A determination is made when the obtained location of the resection equipment is within the defined virtual protection area. The resection equipment is disabled when the determination indicates the obtained location is within the defined virtual protection area. Accordingly, this technology advantageously allows a surgeon to intraoperatively establish a protection area to facilitate automated protection of particular anatomical structures from resection.

The invention relates to the technical field of motor control, in particular to a speed compensation method for a motor to drive an eccentric load to vertically rotate and a related device. The method comprises the following steps: enabling an eccentric load to be vertically downward through a mechanical tool, and collecting and storing vertical zero position data of the eccentric load to a nonvolatile memory for establishing a gravity direction reference; and acquiring current position data of the eccentric load in real time, calculating a difference value between the current position data and the vertical zero point position data, and converting the difference value into relative position data in a range of [0, 2pi] for determining a load phase angle. According to the method, the eccentric load is fixed to be vertically downward through the mechanical tool, zero point position data are stored in the nonvolatile memory, and a space phase reference strictly aligned with a gravity field is established. The physical certainty of the reference eliminates the interference of accumulative errors of a traditional position sensor on phase calculation, and an absolute reference system is provided for a compensation algorithm.

The invention relates to an improved method for manufacturing a so-called final socket (2') from a provisional socket (2), for fitting a residual limb of an amputee. The method comprises 3D modeling of the inner surface of the provisional socket (2), including a 3D model (44) of said surface in a spatial reference frame (11), and automatic modification of said 3D model (44) to optimize the arrangement of an artificial limb (3) on the final socket (2). The method further comprises optimizing a digitization step by determining an improved position for a distance measuring tool (42) within the provisional socket (2) during modeling. The invention also relates to a manufacturing aid system for a final socket configured to implement the method of the invention. Fig. 8

The invention discloses a deep learning-based intelligent recognition method for a motion mode of an unmanned surface vehicle. The method comprises the following steps: acquiring original sensing data in real time through a multi-source sensor system mounted on the unmanned surface vehicle, wherein the multi-source sensor system at least comprises an inertial measurement unit (IMU), a global navigation satellite system (GNSS) receiver, a laser radar and a visible light camera; performing time synchronization and coordinate system alignment processing on the original sensing data to generate a fused sensing data stream with a unified timestamp and a spatial reference system; dividing the fused sensing data stream into time window segments with fixed lengths, wherein each time window segment corresponds to one to-be-identified motion state sample; the IMU, the GNSS, the laser radar and the visible light / infrared camera are synchronously integrated, quadruple sensing dimensions are formed, the IMU captures instantaneous acceleration and angular velocity changes and reflects control instruction execution, the reliability of single-point observation is improved, and the system can still maintain the basic recognition capability when part of sensors fail.