Beihang University

Boe Technology Group Co., Ltd.

Ordos Yuansheng Optoelectronics Co., Ltd.

Beijing University of Aeronautics and Astronautics

Telefonaktiebolaget Lm Ericsson (publ)

Ndsu-research Foundation

Guangjun Zhang

Zhenzhong Wei

Jie Jiang

Junhua Sun

Qiaoyun Fan

Zhen Liu

Fuqiang Zhou

Qianzhe Liu

Xue Dong

Wei Wang

Ying Wang

Zhen Wang

Yali Wang

Zhaohui Meng

Wen Sun

Zhifu Li

Lina Liu

Yuanchun Xie

Suranjan Panigrahi

Meng Xie

Qingbo Li

Nan Lu

Suqi Li

Weixian Li

Zhipeng Cao

Xuetao Hao

Xinguo Wei

Dazhi Chen

Yanmin Feng

A stellar atmospheric refraction measurement correction method based on collinearity of refraction surfaces, comprising: performing star identification on the basis of observed star vectors in a star sensor and the reference star catalog, to obtain matching relationships between observed stars and reference stars; converting reference star vectors corresponding to the observed stars to a geographic coordinate system before entering the atmosphere to obtain zenith distances and azimuth angles of incident stellar; on the basis of a principle of collinearity of refraction surfaces, performing optimal solving according to imaging coordinates of observation stars, to obtain the optimal position coordinates of the zenith direction on an imaging surface of the star sensor; according to the optimal zenith direction, performing atmospheric refraction correction on all the recognized observed stars by means of the trigonometric cosine formula to obtain corrected star coordinates; and performing optimal solving to obtain the attitude of the star sensor in the geographic coordinate system.

Stellar atmospheric refraction measurement correction method based on collinearity of refraction surfaces

A touch display device is provided. The touch display device comprises a display panel (), the display panel () has a plurality of pixel units (), each of the pixel units () includes a functional region (), and a non-functional region () is formed between functional regions () of adjacent pixel units. The touch display device further comprises a plurality of lines of sensor units (), and adjacent sensor units in each line of the sensor units are electrically connected with each other by a connection unit. The connection unit includes a connection bridge (), a projection of at least part of the connection bridge () on a light emission surface of the display panel () is located in the non-functional region () between the functional regions () of adjacent pixel units and extends in an extension direction of the non-functional region (). A shadow dispelling effect of the connection bridge is improved, and display quality of the touch display device is improved.

Touch display device

Disclosed is a display driving method, an upper machine, a lower machine and a display driving system. The method includes: acquiring, by a lower machine, an address for any of subpixels transmitted from an upper machine; looking up, by the lower machine, a gray scale data corresponding to the pointer address in a display Look-UP Table (LUT), wherein the LUT stores mapping relationships between respective pointer addresses and their corresponding gray scale data; performing, by the lower machine, a digital-analog conversion on the gray scale data to acquire a converted analog voltage; and outputting the analog voltage to the subpixel so as to drive the subpixel for displaying. The method can increase the transmission rate between the GPU and the display to a certain degree and reduce the power consumption thereof.

Display driving method, upper machine, lower machine and display driving system

A method and software for the simultaneous pose and points-correspondences determination from a planar model are disclosed. The method includes using a coarse pose estimation algorithm to obtain two possible coarse poses, and using each one of the two coarse poses as the initialization of the extended TsPose algorithm to obtain two candidate estimated poses; selecting one from the two candidate estimated poses based on the cost function value. Thus, The method solves the problem of pose redundancy in the simultaneous pose and points-correspondences determination from a planar model, i.e., the problem that the numbers of estimated poses increase exponentially as the iterations go. The disclosed embodiment is based on the coplanar points, and does not place restriction on the shape of a planar model. It performs well in a cluttered and occluded environment, and is noise-resilient in the presence of different levels of noise.

Method and computer program product of the simultaneous pose and points-correspondences determination from a planar model

The present disclosure provides a global calibration method based on a rigid bar for a multi-sensor vision measurement system, comprising: step 1, executing the following procedure for at least nine times: placing, in front of two vision sensors to be calibrated, a rigid bar fasten with two targets respectively corresponding to the vision sensors; capturing images of the respective targets by their corresponding vision sensors; extracting coordinates of feature points of the respective targets in their corresponding images; and computing 3D coordinates of each feature points of the respective targets under their corresponding vision sensor coordinate frames; and Step 2, computing the transformation matrix between the two vision sensors, with the constraint of the fixed position relationship between the two targets. The present disclosure also provides a global calibration apparatus based on a rigid bar for a multi-sensor vision measurement system. Putting the present disclosure to use can increase the accuracy of the global calibration, and also be suitable for the calibration of the multi-sensor vision system in the extremely large working space, which enlarges the application range of the present disclosure.

Global calibration method with apparatus based on rigid bar for multi-sensor vision

The present disclosure provides a microscopic vision measurement method based on the adaptive positioning of the camera coordinate frame which includes: calibrating parameters of a microscopic stereo vision measurement model (); acquiring pairs of synchronical images and transmitting the acquired images to a computer through an image acquisition card (); calculating 3D coordinates of feature points in a scene according to the matched pairs of feature points in the scene obtained from the synchronical images and the calibrated parameters of the microscopic stereo vision measurement model (); and performing specific measurement according to the 3D coordinates of the feature points in the scene (). With the method, the nonlinearity of the objective function in the microscopic vision calibration optimization is effectively decreased and a better calibration result is obtained.

Microscopic vision measurement method based on adaptive positioning of camera coordinate frame

A thermal pad () formed on a Printed Circuit Board and a method () of formed the thermal pad () are provided. The thermal pad () comprises in its interior one or more coins () has a height equal to a thickness of the PCB, and is made of metal or alloy, inserted into a corresponding one of one or more plated cutouts straight through the PCB in the thermal pad, and bonded to side walls of the corresponding one of the one or more plated cutouts with a paste capable of resisting a temperature of 250&#xb0; C. or above. The plurality of through via () are plated, and lugged with a solder mask. The thermal pad () has a flat top surface and a flat bottom surface, either of which is coplanar with a corresponding one of top and bottom surfaces of the PCB. A PCB having formed thereon the above thermal pad () is also provided.

Thermal pad and method of forming the same

This disclosure provides a calibration method for structure parameters of a structured-light vision sensor, which includes setting up the coordinate frames of a camera, image plane and target for calibration. The calculation of coordinates in the camera coordinate frame of stripes, projected by structured-light, on the planar target and a structured-light equation fitting according to the coordinates in the camera coordinate frame of the stripes on the planar target, by moving the planar target arbitrarily multiple times. The calibration method of the structured-light vision sensor provided by the disclosure is easy to operate and no auxiliary apparatus is needed, which can not only promote the efficiency of the calibration of structured-light, but also extend the application scope of calibration of structured-light.

Calibration method for structure parameters of structured-light vision sensor

The invention discloses a vehicle dynamic measurement device for comprehensive parameters of rail wear, which comprises a vision sensor, a computer and a milometer. A high-speed image acquisition card and a measurement module are installed in the computer. The vision sensor comprises imaging system for rail cross-section and a raster projector which can project more than one light plane perpendicular to the measured rail. The measurement module is used for calculating vertical wear, horizontal wear, the amplitude and wavelength of corrugation wear. The invention also discloses a vehicle dynamic measurement method for comprehensive parameters of rail wear. The invention can increase the sampling rate of image sensing and acquisition hardware equipment with no need of improving the performance of it, thereby satisfy high-speed on-line dynamic measurement requirements for corrugation wear, and the amplitude and wavelength of corrugation wear can be calculated more precisely.

Vehicle dynamic measurement device and method for comprehensive parameters of rail wear

The disclosure relates to a rapid and high precision centroiding method for spots image comprising the following steps. First, the method requires convoluting the gray value of a pixel with a Gaussian filter and judging whether the result thereof exceeds a predetermined threshold. If the value exceeds the predetermined threshold, the method requires marking the current pixel with a flag to identify which spot it belongs to, and then accumulating the product of the gray value and a coordinate value of the same spot; and at the same time, accumulating the gray value of the same spot; and saving the results of the accumulation respectively. If the gray value of the pixel does not exceed the predetermined threshold, the method requires marking the current pixel as a background flag. After all pixels of the image has been disposed of completely, the method includes calculating a quotient of the accumulations of the product of the gray value and the coordinate value and the accumulations of the gray value, and outputting the quotients. At the same time, a centroiding system for spots image is also presented.

Rapid and high precision centroiding method and system for spots image

The present disclosure is directed to a three-dimensional data registration method for vision measurement in flow style based on a double-sided target. An embodiment of the disclosed method that comprises A. Setting up two digital cameras which can observe the entire measured object; B. Calibrating intrinsic parameters and a transformation between the two digital camera coordinate frames; C. A double-sided target being placed near the measured area of the measured object, the two digital cameras and a vision sensor taking images of at least three non-collinear feature points of the double-sided target; D. Removing the target, measuring the measured area by using the vision sensor; E. Respectively computing the three dimensional coordinates of the feature points in the global coordinate frame and in the vision sensor coordinate frame; F. Estimating the transformation from the vision sensor coordinate frame to the global coordinate frame through the three dimensional coordinates of the three or more non-collinear feature points obtained at step E, then transforming the three dimensional data of the measured area to the global coordinate frame; and G. Repeating step C, D, E, F, then completing three dimensional data registration for all measured areas. The present disclosure improves three dimensional data registration precision and efficiency.

Three-dimensional data registration method for vision measurement in flow style based on double-sided target

A method for calibration of a digital celestial sensor is disclosed. First, an integrated mathematic model for imaging of a celestial sensor is established according to external and internal parameters of the calibration system of the celestial sensor. Second, by rotating two axes of a rotator by different angles, calibration points data are acquired and sent to a processing computer through an interface circuit. Finally, a two-step calibration program is implemented to calculate the calibration parameters by substituting calibration points' data to the integrated mathematic model. An application device of the calibration method is also provided. The device may include a celestial simulator to provide simulated sunlight or starlight, a two-axis rotator to acquire different calibration points' data, and a processing computer to record the calibration points' data and calculate the calibration parameters.

Method and device for calibration of digital celestial sensor

The present invention relates to a high-performance computer vision system and method for measuring the wings deformation of insects with high flapping-frequency, large stroke-amplitude and excellent mobility during free-flight. A geometrical optic unit composed of a polyhedral reflector with four reflection-planes and four planar reflectors is used to image one high-speed CMOS camera to four virtual cameras, combined with double laser-sheet sources, multiple virtual stereo and structured-light sensors are available to observe the free-flight of insect at different viewpoints simultaneously. In addition, an optoelectronic guiding equipment is included to lead the free-flight of insect and trigger the camera to capture the image sequences of insect-flight automatically. The deformation of insect-wings can be reconstructed by the spatial coordinates of wing-edges and the distorted light-lines projected on the surface of wings.

Methods and apparatus for measuring the flapping deformation of insect wings

The disclosure relates to a hardware-in-the-loop simulation system and method for computer vision. An embodiment of the disclosed system comprises a software simulation and a hardware simulation. The software simulation includes a virtual scene and an observed object that are generated by virtual reality software. The virtual scene images are obtained at different viewpoints. The hardware simulation includes the virtual scene images being projected onto a screen by a projector, wherein the projected scene images are shot by a camera, and where in the direction of the camera is controlled by a pan-tilt.

Hardware-in-the-loop simulation system and method for computer vision

The disclosure relates to a signal processing method for multi aperture sun sensor comprising the following steps: reading the information of sunspots in a row from a centroid coordinate memory, judging the absence of sunspots in that row, identifying the row and column index of the sunspots in the complete row, selecting the corresponding calibration parameter based on the row and column index, calculating attitude with the attitude calculation module the corresponding to identified sunspots, averaging the accumulated attitude of all sunspots and outputting the final attitude. At the same time, a signal processing device for multi aperture sun sensor is also presented. It is comprised of a sunspot absence judgment and an identification module and an attitude calculation module. The disclosure implements the integration of sun sensors without additional image processor or attitude processor, reduces field programmable gate array resource and improves the reliability of sun sensors.

Growing community of inventors

Beijing, China

Guangjun Zhang