309results about How to "Achieve reconstruction" patented technology

The invention discloses a three-dimensional point cloud reconstruction device and a three-dimensional point cloud reconstruction method based on a multi-fusion sensor. The device comprises a multi-fusion sensor module, a system data processing module and a three-dimensional point cloud reconstruction module. The method comprises the following steps: acquiring point cloud data and a video image byusing a multi-fusion sensor device, and processing the video image to obtain a target image including target posture, position and texture information; acquiring target point cloud corresponding to the original point cloud according to the acquired posture position information in the original point cloud and the target image; filtering the point clouds to remove messy point clouds; wherein the point cloud coarse registration comprises key point quality analysis; point cloud fine registration; and inputting the registered point cloud into a point cloud reconstruction unit to realize three-dimensional point cloud fusion and reconstruction. According to the method, the feature points corresponding to the target image reconstruction point cloud corresponding to the original three-dimensional point cloud are extracted to obtain the target three-dimensional space position information, texture and color information. Therefore, the point cloud registration precision is improved, and the falseidentification and tracking loss probability is effectively reduced.

The present invention provides a real-time three-dimensional scene reconstruction method for a UAV (unmanned aerial vehicle) based on the EG-SLAM. The method is characterized in that: visual information is acquired by using an unmanned aerial camera to reconstruct a large-scale three-dimensional scene with texture details. Compared with multiple existing methods, by using the method provided by the present invention, images are collected to directly run on the CPU, and positioning and reconstructing a three-dimensional map can be quickly implemented in real time; rather than using the conventional PNP method to solve the pose of the UAV, the EG-SLAM method of the present invention is used to solve the pose of the UAV, namely, the feature point matching relationship between two frames is used to directly solve the pose, so that the requirement for the repetition rate of the collected images is reduced; and in addition, the large amount of obtained environmental information can make theUAV to have a more sophisticated and meticulous perception of the environment structure, texture rendering is performed on the large-scale three-dimensional point cloud map generated in real time, reconstruction of a large-scale three-dimensional map is realized, and a more intuitive and realistic three-dimensional scene is obtained.

The invention discloses a mirror movement neuromodulation system, which comprises a plurality of lead biological signal amplifiers, a microcomputer controller, a plurality of lead functional electric stimulators and a micro-current direct-current constant-current stimulator. The principle that functional electric stimulation and transcranial direct-current electric stimulation techniques and mirror movement neurons participate in movement control is applied comprehensively, the biological signal amplifiers, the functional electric stimulators for simulating integrated electromyography envelope signal control, and the micro-current direct-current constant-current stimulator are integrated through the microcomputer controller, myoelectric activity envelope signals are generated by processing myoelectric signals of a plurality of muscle groups which move functionally by using an uninjured side limb, and the plurality of functional electric stimulators are modulated and controlled, so that the same mirror action is generated by the plurality of muscle groups of an injured limb on an opposite side according to uninjured side myoelectric information, brain functional regulation and reconstruction are realized, the plasticity of neuronal synapsis and the recovery of neurological functions are facilitated, and the treatment effect of sports rehabilitation is achieved.

The invention provides a fractal multi-resolution simplified method used for large-scale terrain rendering. The method comprises the following steps: (1) determining a terrain grid rendering region in a scene, firstly carrying out equidistant grid resampling on DEM (digital elevation model) data of coarser grids to form a terrain quadtree node; (2) projecting a view point to an XOZ plane, creating a terrain multi-resolution frame, and setting a plurality of different resolution levels from 1 to n on the terrain by adopting the multi-resolution LOD (level of detail) technology according to the view point; and (3) determining the level of the terrain according to the distances between the view point and different regions of a model, extracting characteristic parameters from an original DEM data set, adopting a DEM-based fractal random midpoint displacement interpolation to generate a continuous real terrain, and realizing reconstruction of a large-scale terrain. The terrain realized by adopting the method in the invention has good space continuity, cracks between different levels in a common multi-resolution model can be avoided, and smooth transition of different resolution models can be realized.

The invention provides a microscopy CT imaging device with three-free degree motion control and a correcting method thereof. The microscopy CT imaging device comprises an X-ray source (1) and an X-ray source detector (2), wherein a material-carrying table (3) is arranged between the X-ray source (1) and the X-ray source detector (2). The device is characterized in that the material-carrying table is externally provided with a driving device for driving the material-carrying table to move along the horizontal direction, the vertical direction and the rotation direction. The device solves the problems of serious shake, large error and low precision when the common microscopy CT mechanical device moves; leads the three-free degree direction motion to be more stable, the speed to be more even, and the precision degree to be higher; has better radiation shield effect; solves the problem of the heat dissipation of the X-ray source and the X-ray source detector; solves the problem that the X-ray source, the X-ray source detector and a material-rotating center are positioned at one line; and lays good foundations for the subsequent image acquisition and image reconstruction.

Endoscopic images and virtual endoscopic images are obtained. Then, an endoscopic image captured at a predetermined position of the anatomical structure is extracted from the obtained endoscopic images, and a comparative virtual endoscopic image virtually generated as if it is captured at a position corresponding to the predetermined position is extracted from the obtained virtual endoscopic images, and the extracted images are associated with each other. A three-dimensional position corresponding to each pixel forming the endoscopic image captured at the predetermined position is calculated based on a three-dimensional position of each pixel forming the comparative virtual endoscopic image. Then, volume data is generated from the endoscopic image captured at the predetermined position based on a pixel value of each pixel forming the endoscopic image and the three-dimensional position calculated for each pixel.

The invention discloses a blade shape rapid scanning device and method. The device includes a base, an X main shaft, a Y main shaft, a Z main shaft, a turntable, a noncontact optical probe and a contact probe; the X, Y, Z main shafts and the turntable are arranged on the base; wherein the X, Y, Z main shafts are used to drive the probes to move freely in the space X, Y and Z; the turntable is used to drive a blade to rotate in the measuring space; the non-contact optical probe and the contact probe are commonly mounted on the Y main shaft through a connecting member; the non-contact optical probe is used to measure the blade surface with low precision, obtains all the point cloud data of the blade and plans the measuring path; and the contact probe is used for high-precision measurement of the blade surface along a well-planned measuring path.

The invention relates to a method for reconstructing a large-scale complex flyover 3D model by using airborne LiDAR data. The method includes the following steps: using inverse iteration mathematic morphological filtering and area information to extract flyover point cloud from airborne LiDAR data; in accordance with bridge floor connectivity, segmenting the flyover cloud point; adopting a central line vertical line scanning method to segment and extract a communicated bridge surface which has no bifurcation or intersection structures and has a width consistent width, acquiring a "constitutional unit"; an end place of the constitutional unit central line serving as a circular buffer area, detecting a shielding structure of the flyover through determination of point cloud height information within the buffer area; through steps of constitutional unit matching, 2D central line fitting and 3D curved surface fitting, acquiring a complete bridge surface 3D central line; and reconstructing a flyover 3D model in combination with bridge surface width information. Practice has proved that the method of the invention can effectively reconstruct the large-scale complex flyover 3D model, addresses shielding problem of the flyover point cloud, and the reconstructed 3D model has a higher correctness and completeness.

The invention discloses a visual navigation and inertial navigation combination navigation method based on an aircraft. The method comprises the following steps: 1, establishing a two-dimensional planar rectangular picture coordinate system; 2, acquiring video image data and aircraft pose data, and preprocessing images; 3, continuously tracking a characteristic point; 4, establishing a three-dimensional flight-path coordinate system; 5, calculating the speed vector of the flight-path; 6, resolving the attitude of the aircraft; 7, fusing data, and calculating the flight-path angle; 8, carrying out coordinate transformation, and acquiring the displacement matrix of the aircraft; and 9,repeating step 3 to step 8 multiple times until the continuous acquisition of the displacement matrix set of the images is completed in order to achieve the continuous combination navigation. The movement flight-path speed vector of the aircraft is obtained through visual navigation, the inertial navigation data is fused, and the error of the visual navigation is compensated and corrected to reconstruct the flight-path of the aircraft, so the aircraft can stably and autonomously fly.

The invention discloses a low-dose X-ray CT image reconstruction method. The low-dose X-ray CT image reconstruction method sequentially comprises the steps that (1) imaging system parameters of CT equipment and projection data in low-dose CT scanning protocol are obtained, (2) the projection data variance on each data point is calculated according to the projection data obtained in the step (1) and the position of each data point and the number of all the data points are showed, (3) a projection data recovery model is established according to the projection data variances estimated in the step (2), (4) solving is carried out according to the projection data obtained in the step (1) by means of the projection data recovery model established in the step (3) to obtained recovered projection data, and (5) image reconstruction is carried out according to the recovered projection data obtained in the step (4) to obtain a reconstructed CT image. The low-dose X-ray CT image reconstruction method has the advantages that noise and artifact of the image can be greatly reduced, the resolution ratio of the original image can be well kept, and high-quality reconstruction of the CT image is finally achieved.

The invention discloses a positioning control method of a flexible mechanical arm based on vision. The method includes the following steps of obtaining information of a feature area on a robot mechanical arm, obtaining the positions and postures of a base, joint rotating centers and the tail end of a mechanical arm through coordinate system conversion, and controlling the movements of the flexiblemechanical arm. A positioning control device of the flexible mechanical arm based on vision comprises the robot base and the mechanical arm, and further comprises a first motor, a second motor and amicroprocessor, wherein the feature area is arranged on the mechanical arm. The feature area on the flexible arm is detected and positioned by means of the cameras, and therefore the positions of thejoint rotating centers in a camera coordinate system are obtained, and the reconstruction of the arm type of the flexible arm is realized; through the comparison with the positions of the tail end andall the joint rotating centers in theory, the movement bias of the mechanical arm is corrected, the movement precision of the flexible mechanical arm is improved, and the positioning control method and device are widely applied to the mechanical arm control field.

The invention discloses a method and device for reestablishing a user database on a block chain, terminal equipment and a storage medium. The method for reestablishing the user database on the block chain comprises the steps of reading all data items on the block chain, wherein each data item is obtained after being encrypted through a preset encryption algorithm; adopting a decryption algorithm corresponding to the encryption algorithm for decrypting each data item, and obtaining a decrypting result of each data item; if the decrypting results carry user identifiers, determining the data items as user data information corresponding to the user identifiers, and saving the data information; based on indexes and data secret keys, establishing a corresponding relationship of the data information on the block chain, and reestablishing the user database on the block chain. By means of the method for reestablishing the user database on the block chain, a user can find back missing data fromthe block chain, and the user database is reestablished.

The invention discloses a passive single pixel telescope imaging system, and belongs to an optical imaging field. The passive single pixel telescope imaging system comprises an imaging lens, a spatial light modulator, a light beam convergent lens and a data acquisition card, which are orderly arranged on a light path; the spatial light modulator is arranged at an imaging position of the imaging lens; the light beam convergent lens is located on a light path of an output beam of the spatial light modulator; the data acquisition card is provided with a photovoltaic conversion chip; the data acquisition card and the spatial light modulator are connected with a processor through a data line. The imaging system is simple in structure and low in environmental requirement; besides, the acquisition time can be effectively reduced and the recovery of target images under a low sampling rate can be realized. The invention further discloses a passive single pixel telescope imaging method. The imaging method is simple in recovery algorithm and fast in image reconstruction speed, and can shoot and reconstruct the images of large sizes, so that the imaging method has a higher application value in the macro fields like military, remote sensing satellite, astronomy and engineering detection, etc.

The invention discloses a probe type online three-dimensional imaging detection system which comprises a crystal growth reactor, a three-dimensional imaging probe, a light source and a strobe controller, a computer for processing an image, and a display, wherein the three-dimensional imaging probe is used for transmitting a 2D image to the computer; the computer is used for firstly deleting a background by using a splitting technology and then identifying corresponding points and lines from the 2D image by using an angle/edge/line detection technology; for few angles/lines which are detected difficultly, indistinct angles/lines are predicted/estimated by using molecule modeling and a crystal shape model on the basis of the obtained angles and lines, 3D image reconstruction is realized by using the determined points and lines, then particle description characteristics of 3D crystals are obtained by combining with solution parameters measured online, and finally, the control and the amplification of a crystallization process in a reactor are realized by using a crystalline form grain number balancing model and computational fluid mechanics. The system and the method provided by the invention are capable of directly acquiring the image from the solution and realizing the reconstruction of the 3D crystalline form, and are high in image processing speed.

Embodiments of the invention provide a database cluster metadata management method and system. The method comprises the steps that a cluster initiation node receives a management request sent by a client and sends a locking request to a global lock management entity; the global lock management entity receives the locking request, judges whether a lock conflict exists or not and judges whether an available lock resource exists or not; when no lock conflict exists and the lock resource exists, a locking success response is sent to the cluster initiation node; the cluster initiation node receives the locking success response and sends a metadata management request to other nodes in a cluster; all nodes in the cluster manage metadata according to the request and sends a response success message to the cluster initiation node after the management is completed; and the cluster initiation node receives the response success message and sends an unlocking request to the global lock management entity. The problem of cluster metadata inconsistency caused by the fact that clients accessing to different cluster nodes initiate the same metadata management request at the same time in a high-concurrency scene is solved.