70 results about "Frame of reference" patented technology

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.

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.

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

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.

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.

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

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.

This invention relates to an attitude calculation method for an unmanned aerial vehicle (UAV) attitude reference system, belonging to the field of UAV navigation. In this invention, the collected sensor data is first filtered to obtain an initial unit quaternion from the navigation coordinate system to the vehicle coordinate system. The accelerometer output is normalized and an error vector is constructed with the normalized gravity vector. The vehicle motion mode is determined by the accelerometer and gyroscope outputs, and the gain coefficient is adaptively adjusted to calculate the gyroscope error correction, thus completing the attitude update and correcting the horizontal attitude. Simultaneously, the magnetometer output is evaluated; if the magnetometer output is valid, the heading angle is corrected, and the corrected three-axis attitude angles are output in real time. This invention uses only quaternions for calculation, avoiding the calculation of rotation matrices and improving calculation efficiency. Compared to traditional complementary filtering algorithms, it incorporates vehicle motion mode judgment and adaptive complementary filter parameter adjustment, avoiding erroneous attitude corrections by the accelerometer under high dynamic conditions. By applying a second-order complementary filter to process accelerometer and magnetometer data for attitude compensation, horizontal attitude correction can be avoided when magnetometer data is unavailable, achieving decoupling of attitude correction.

The present disclosure relates to methods (200; 300; 400) for use in a moving platform for initialization of a visual-inertial odometry system (100) comprising a camera (1) and an inertial measurement unit (2), IMU. The methods comprise determining (201) point correspondence between at least a first image captured by the camera and a textured 3D model of an environment containing 3D coordinates given in a predetermined global coordinate system. The methods further comprise determining a relative rotation between the predetermined global coordinate system used for the camera and a IMU coordinate reference system, or estimating (210) a relative translation and rotation between the first and second images in a scale of the predetermined global coordinate system using the determined first and second point correspondences, said estimate indicating the scale for movement of the camera (1) for use in initialization of the visual odometry system.

A data communication method for a de-icing system for a turbine engine is disclosed. The turbine engine includes a fixed reference frame and a rotating reference frame. The system includes a non-contact rotating power transformer (RTU), the primary side of which is constrained by the fixed reference frame, and the secondary side of which is constrained by the rotating reference frame. The fixed reference frame includes an ice protection and control unit (IPC) and a power supply device (DC / AC) for supplying AC power to the primary side. The IPC transmits commands to the DC / AC to adjust the level of power supplied to the primary side. The rotating reference frame includes a propeller (1) and a switch, with a plurality of resistors fixed to the propeller. The switch is used to sequentially distribute the power supplied to the secondary side to the resistors. The protection and control unit (IPC) is programmed to transmit switching commands to the switch via the power supply unit (DC / AC) and the transformer (RTU) by issuing instructions (Ic1, Ic2, Ic3, Ic4, Ic5, Intl) to the power supply unit (DC / AC) to encode the voltage wave sequence (To) applied to the primary side. The switch is programmed to decode the voltage wave sequence (To) recovered on the secondary side.

A method of video encoding leverages camera pose information to enhance inter-frame prediction efficiency. The method includes obtaining a plurality of reference frames for a current frame, determining a camera pose for each of the plurality of reference frames and the current frame, selecting a subset of the plurality of reference frames based on the camera poses, and performing inter-frame prediction for the current frame using the selected subset of reference frames. This approach utilizes real-time motion data from inertial measurement units (IMUs) to identify reference frames with maximum temporal correlation to the current frame, thereby reducing the computational load required for inter-frame prediction. The method may include retrieving the reference frames from a reference frame buffer, using gyroscope data to calculate the camera poses, or representing the camera poses using quaternion data.

This invention discloses a method and system for implementing a completely reference-frame-independent quantum key distribution protocol, belonging to the field of quantum information technology. Alice and Bob, the communicating parties, randomly select mutually unbiased basis vectors to prepare quantum states and send them to a third party, Charlie. Charlie performs Bell state projection measurements and announces the success. Both parties publish the basis vector information, divide the dataset, and calculate the gain and bit error rate. A 3×3 correlation tensor matrix is ​​constructed and singular value decomposition is performed to obtain three reference-frame-independent singular values. The secure key rate is calculated based on the bit error rate. Finally, key negotiation and security enhancement are performed to extract the secure key. This invention does not require basis vector alignment, completely eliminating the dependence on reference frame calibration. It can still stably generate keys even with basis vector drift, and the amount of information required by eavesdroppers is lower, significantly improving the practicality and security of the quantum key distribution system.

An example method of video decoding includes receiving a video bitstream comprising a plurality of frames, and deriving a derived primary reference frame from a set of reference frames for a current frame of the plurality of frames. The method also includes parsing a signaled primary reference frame for the current frame and obtaining respective contexts for the signaled primary reference frame and the derived primary reference frame. The method further includes initializing a current frame context for the current frame by performing a weighted average of the respective contexts, and entropy decoding one or more syntax elements for the current frame using the current frame context. The method also includes reconstructing the current frame using information of the one or more syntax elements.

The application provides an auxiliary calibration method for an AGV navigator installation position and a program product, and relates to the technical field of AGV navigation.The method comprises the following steps: firstly, controlling a target AGV to run and determining a target point NavPos1; secondly, marking a ground marker point PhyPos1; thirdly, controlling the target AGV to run and determining a target point NavPos2; fourthly, determining whether calibration can be performed according to the deviation of NavPos1 and NavPos2; fifthly, marking a ground marker point PhyPos2; and finally, calculating an actual installation point Nav of the target AGV navigator according to the deviation of PhyPos1 and PhyPos2 and determining whether to perform update iteration to ensure calibration accuracy.The auxiliary calibration method provided by the application no longer needs to depend on expensive external equipment or a complex reference system, simplifies the operation process, and is not limited by a working environment.

The application discloses a map construction method and device, electronic equipment and a storage medium, and relates to the technical field of data fusion. In the application, radar point cloud data and image acquisition data collected from a to-be-measured area are acquired, and the radar point cloud data and the image acquisition data are analyzed respectively to obtain a first measurement pose and a second measurement pose of a map construction device in a standard coordinate reference system, so that a target fusion pose of the map construction device is obtained based on the first measurement pose and the second measurement pose, and then a map of the to-be-measured area is constructed based on the target fusion pose, the radar point cloud data and the image acquisition data. In this way, the technical defect that the accuracy of map construction is low due to the fact that the poses of the map construction devices determined by a laser SLAM constructed map and a visual SLAM constructed map are different is avoided, so that tight coupling of multiple sensors is achieved, and the accuracy of map construction is improved.

Aspects presented herein may enable a first UE to locate a second UE via an anchor device when they are not within a direct communication with each other, and also when they are moving. In one aspect, a first UE communicates, with a second UE, an anchor device to be used for tracking a position of the second UE. The first UE obtains a first set of measurements based on a reference frame of the first UE. The first UE receives, from the second UE, a second set of measurements based on a reference frame of the second UE. The first UE estimates the position of the second UE based on the first set of measurements and the second set of measurements.

A non-rigid anatomy reference system can include reference markers that are rigidly attachable to separate bodies of rigid tissue connected through flexible tissue in a region of a patient forming a marker array. A tracking system can acquire movement data of the reference markers as a function of time and position. A processor can be configured to: receive the movement data, where an individual reference marker has a first number of degrees of freedom less than 6 and a second reference marker having a second number of degrees of freedom; track the marker array as a whole with a total number of degrees of freedom greater than the first and the second number; and produce an updated image of the region of the patient to maintain registration to a prior image of the region and the tracked movement of the reference markers via the function.

A multi-stream cross correlator for spiking neural networks, where each stream contains significant stochastic content. At least one event occurs, with a fixed temporal relationship across at least two streams. Each stream is treated as a Frame Of Reference (FOR), and subject to an adjustable delay based on comparison to the Other streams. For each spike of the FOR, a timing analysis, relative to the last and current FOR spikes, is completed by comparing Post and Pre accumulators. Also, a new timing analysis is begun, with the current FOR spike, by restarting the production of Post and Pre weighting functions, the values of which are accumulated, upon the occurrence of each Other spike, until a next FOR spike. A one-spike delay unit can be used, if time-neutral conflict resolution is used. The average spike rate of the FOR can be determined and used for the Post and Pre weighting functions.

The invention relates to a method for controlling a robot, comprising the following steps: providing (S10) a first data processing based at least in part on machine learning in order to determine a target movement of a first reference frame fixed to the robot; providing (S10) a second data processing based at least in part on machine learning to determine a nominal motion of a second reference frame fixed to the robot; determining (S20) a target axis movement of the robot on the basis of a target movement of the first reference frame determined by means of the first data processing and a target movement of the second reference frame determined by means of the second data processing, the determined rated motion of the first reference frame is prioritized relative to the determined rated motion of the second reference frame; and controlling (S30) the robot on the basis of the determined target axis movement. The invention also relates to a system or computer program (product).

A method comprising: obtaining a coordinate set of a set of access points (APs) (210), wherein the coordinate set (410) is provided using the Earth as a reference system; calculating a distance between APs, representing a first set of distance measurements calculated for the set of APs; obtaining a second set of AP-to-AP distance measurements for the set of APs; and performing a data correction process by reconciling the first set of distance measurements and the second set of AP-to-AP distance measurements, wherein the data correction process comprises: determining a set of deviations between an area calculated from the coordinate set and the second set of AP-to-AP distance measurements;and updating the coordinate set by adjusting the coordinate set based on the set of deviations, wherein the data correction process reduces deviations between the coordinate set and the second set of AP-to-AP distance measurements, wherein the updated coordinate set is mapped to specific physical locations of the set of APs, and wherein the data correction process determines the updated coordinate set when transmission signals are obstructed by physical barriers or building boundaries.

In some embodiments, a method comprises: receiving acceleration data from a motion sensor of a mobile device carried by a user, the acceleration data represented by a space curve in a three-dimensional (3D) acceleration space, the space curve indicative of a cyclical vertical displacement of the user's center of mass accompanied by a lateral left and right sway of the center of mass when the user is stepping; computing a tangent-normal-binormal (TNB) reference frame from the acceleration data, the TNB reference frame describing instantaneous geometric and kinematic properties of the space curve over time; and computing a direction of travel of the user based on an orientation of a unit binormal (B) vector of the TNB reference frame in the 3D acceleration space, and computing a speed of the user based on a linear regression model applied to the kinematic properties of the TNB reference frame.

An example method of video decoding includes receiving a video bitstream comprising a plurality of frames, and deriving a derived primary reference frame from a set of reference frames for a current frame of the plurality of frames. The method also includes parsing a signaled primary reference frame for the current frame and obtaining respective contexts for the signaled primary reference frame and the derived primary reference frame. The method further includes initializing a current frame context for the current frame by performing a weighted average of the respective contexts, and entropy decoding one or more syntax elements for the current frame using the current frame context. The method also includes reconstructing the current frame using information of the one or more syntax elements.

A sensor for detecting a position of a mechanical component within a polar spherical coordinate reference system, comprising, accommodated inside a sensor body of the sensor: a linear position sensor configured to detect a first linear coordinate of a position of a free end of a slider in the polar spherical coordinate reference system; an acceleration sensor; an angular speed sensor; a data processing unit configured to: determine a second colatitude coordinate and a third longitude coordinate of said position based on acceleration values and angular speed values detectable by said sensors; store in a memory unit a plurality of sets of three detected polar spherical coordinates representative of a path travelled by the free end of the slider in said reference system.

To provide a method and an apparatus for adaptive reordering for reference frames.SOLUTION: The present disclosure relates to adaptively reordering reference frames for video coding technologies. Template matching (TM) may be used to reorder the reference frames or reference frame pairs for each block by comparing the difference between the template of a current block and the template of a reference block with reference to the motion information of the spatial reference motion information (or spatial motion vectors) and / or temporal reference motion information (or temporal motion vectors). The difference between the template of the current block and the template of the reference block may be calculated for each spatial reference motion information and / or temporal reference motion information, and marked as the score value of the associated reference frames or reference frame pairs. The available reference frames or reference frame pairs are ranked on the basis of the score value.SELECTED DRAWING: Figure 24

Techniques are described for aligning an antenna's frame of reference to that of a transit craft without relying on precise physical antenna alignment during installation. For example, the antenna is installed on the craft in coarse alignment with the craft's three-dimensional reference frame. The antenna is initially steered based on obtaining ephemeris information for a radiofrequency (RF) node and receiving craft attitude and location information from an on-craft navigation system (OCNS). The antenna finds and locks onto an RF signal from the RF node and uses closed-loop tracking to optimize the antenna pointing to maximize signal quality. An alignment mapping is registered based on a misalignment between the optimized antenna pointing and the craft attitude as reported by the OCNS. The alignment mapping can be subsequently exploited to translate real-time attitude data from the OCNS for high-precision pointing and tracking by the antenna.

The present application relates to the field of photogrammetry, and discloses a land space image analysis method based on photogrammetry, comprising: acquiring aerial images and attitude data of a survey area to generate sparse point clouds; distinguishing rigid and non-rigid feature points based on semantic segmentation results; establishing a local vertical reference system for non-rigid points and configuring anisotropic parameters with transverse variance greater than longitudinal variance; mapping the parameters to a global weight matrix using a coordinate rotation matrix, and substituting them into a bundle adjustment model to complete iterative solution, the present application effectively realizes the automatic suppression of non-rigid disturbance of vegetation and water area by constructing an anisotropic weight determination mechanism coupled with physical properties and geometric constraints, and improves the geometric accuracy and stability of three-dimensional reconstruction in complex land space scenes.