45 results about "Absolute positioning" patented technology

The invention discloses a transmission conductor three-dimensional attitude estimation method, system and equipment based on RTK and inertial measurement coupling and a medium, and belongs to the technical field of three-dimensional state monitoring, and the method comprises the following steps: fusing RTK absolute positioning and IMU inertial measurement data, and realizing accurate estimation of the transmission conductor three-dimensional attitude by using extended Kalman filtering; and abnormal identification and risk early warning are carried out based on an attitude calculation result, and finally real-time monitoring and intelligent warning of the state of the power transmission line are realized through a three-dimensional visual platform. According to the method, RTK and IMU data are fused, accurate sensing and continuous tracking of the three-dimensional attitude of the power transmission line are achieved through extended Kalman filtering, the defect that a single technology is insufficient in reliability in a complex environment is overcome, and finally a complete monitoring closed loop of the safety state of the power transmission line is achieved through intelligent early warning and three-dimensional visualization.

The invention relates to the technical field of robot detection, and discloses a Delta mechanical arm precision detection method, system and device and a storage medium, and the Delta mechanical arm precision detection method comprises the steps that multiple actual position coordinates of the tail end of a mechanical arm in the movement process along a preset track are obtained according to a selected detection mode; geometric fitting is carried out based on the actual position coordinates, and corresponding circle center coordinates are determined; the tail end is controlled to move to the circle center coordinates, and actual position coordinates at the moment are obtained; and error information representing an absolute precision error is generated based on a difference value between the position and the circle center coordinate. According to the method, automatic detection of the absolute positioning precision of the manipulator is achieved, and error quantization can be completed without depending on external measuring equipment; the generated error vector accurately reflects the direction and size of system deviation, compensation and correction are facilitated, and the method has the advantages of being high in detection efficiency, reliable in result and high in applicability.

The invention discloses a sky-base collaborative tower camera image high-precision positioning method, which comprises the following steps of: carrying out virtual squint projection on a satellite image based on a high-resolution satellite orthoimage of an area around a tower camera, and mapping the satellite image to a tower camera squint coordinate system; performing multi-scale phase fusion terrain enhancement feature extraction and cross-view matching on the satellite reference image and the tower camera image to obtain high-precision homonymy points and meter-scale control points; block adjustment and absolute positioning are carried out on a reference database image collected by a tower camera; and based on the positioned reference database, carrying out high-precision geographic positioning on the natural resource illegal behaviors. According to the method, high-precision positioning of the tower camera can be efficiently and automatically realized, the positioning efficiency of the tower camera image is remarkably improved, and protection of natural resources is facilitated.

The application provides a vehicle positioning method, a system, an electronic device and a computer storage medium, and relates to the technical field of automatic driving. In the absence of a fixed base station, the observation data of visible satellites is shared by two vehicles, so that the construction and maintenance costs can be saved, and the two-vehicle sharing can also be adapted to complex scenes and network-uncovered areas. In the positioning process, single-difference and double-difference processing is performed on the common visible satellites of the two vehicles, satellite clock errors, receiver clock errors and most atmospheric errors are eliminated, a high-precision relative baseline vector is obtained, and the obtained perception data of the two vehicles are fused and optimized to obtain the absolute positioning of the two vehicles, so that the positioning precision is improved and the absolute positioning reaches a centimeter-level precision. The purpose of providing stable and high-precision vehicle absolute positioning in a dynamic environment without relying on a fixed base station is achieved.

A wide-range absolute positioning electromagnetic induction type linear displacement sensor relates to the technical field of electromagnetic induction type displacement sensors, and comprises a transmit-receive board and an excitation board which can move relatively, and the transmit-receive board is provided with a transmitting winding and three three-phase receiving windings with different pitches; the excitation plate is provided with three rows of excitation coils which are equal to the three three-phase receiving windings in pitch and coincide with the three three-phase receiving windings in center line. The measuring circuit is provided with three parallel processing channels and is used for synchronously acquiring three corresponding phase quantization codes of a measured position in the fine pitch PF, the middle pitch PM and the coarse pitch PC after the transmitting winding is driven for one time; and directly calculating an absolute displacement value in the coarse pitch measuring range through an absolute positioning algorithm based on the three phase quantization codes. And the absolute displacement in the coarse pitch range is directly synthesized by calculating the integer pitch number step by step according to the integer wavelength ratio relationship of the coarse pitch, the medium pitch and the fine pitch. According to the invention, the breakthrough of the electromagnetic induction type displacement sensor from hybrid positioning to true absolute positioning is realized, and the sensor has the advantages of large measuring range, high precision, no data loss in power failure and low power consumption.

The application discloses a kind of tool butt joint method and system, including end setting with laser range finder, positioning tool interface is provided with measured piece;When reaching the position to be corrected, the laser measurement height value is read by laser range finder;The correlation analysis of the installation offset of laser range finder and the projection point on measured piece is carried out, and the coordinate relationship equation is established;Offset is calculated according to coordinate relationship equation, whether offset meets the requirement is judged, if it meets the requirement, then butt joint is completed, if it does not meet the requirement, then translation adjustment is carried out.The application is tested in laboratory, can control robot end absolute positioning accuracy to be below ±0.25mm, satisfies the requirement that robot completes butt joint operation;Uniform processing standard and gauge standard batch processing measured target are used, and quick replacement can be realized;3-point correction algorithm is used, installation error is weakened, and calculation error caused by installation error is further reduced.

The invention provides a vehicle positioning method and system, an electronic device and a computer storage medium, and relates to the technical field of automatic driving, and two vehicles share observation data for visible satellites without depending on a fixed base station, so that the construction and maintenance cost can be avoided, and the vehicle positioning efficiency is improved. Through sharing of the two vehicles, the method can adapt to complex scenes and areas without network coverage; in the positioning process, the common visible satellite of the two vehicles is subjected to single-difference and double-difference processing, the satellite clock error, the receiver clock error and most atmospheric errors are eliminated, a high-precision relative baseline vector is obtained, fusion optimization is performed in combination with the obtained sensing data of the two vehicles, and respective absolute positioning of the two vehicles is obtained. And the positioning precision is improved, so that the absolute positioning reaches centimeter-level precision. The purpose of providing stable and high-precision vehicle absolute positioning in a dynamic environment without depending on a fixed base station is achieved.

This invention discloses an absolute position perception method and system under GPS-denied conditions. The method includes the following steps: Step A: Images captured by rotating a camera at a specific angle are stitched together in a 360° circular pattern to create a panoramic image; Step B: Based on a semantic segmentation method improved by Deeplabv3+, the skyline is extracted from the natural panoramic image formed in Step A; Step C: OpenGL is used to visualize DEM data to form a rendering image, and the Canny operator is used to perform edge detection on the rendering image to output the skyline; Step D: By using VGG16 as a skyline feature encoder for the natural image and the DEM image, and combining it with a Siamese neural network to output the similarity between the two types of skylines, the self-position is perceived. This invention addresses the challenge of perceiving one's own position on the ground in situations such as military applications under GPS-denied conditions, and conducts research on determining one's own position to achieve the goal of absolute positioning that does not rely on GPS and initial position and whose error does not increase over time.

This invention discloses a parameter compensation method, apparatus, device, and storage medium. The method includes: acquiring theoretical and actual DH parameters of a robot; determining a target algorithm based on the robot's current joint position, desired end-effector Cartesian pose, and the singularity of the robot's configuration; determining initial iteration values ​​based on the target algorithm; and performing parameter compensation on the actual DH parameters using the target algorithm based on the initial iteration values, the theoretical DH parameters, the actual DH parameters, and the desired end-effector Cartesian pose. This scheme can compensate for the robot's actual DH parameters, thereby improving the robot's absolute positioning accuracy.

The application discloses a positioning method and system combining optical positioning and mechanical positioning, and belongs to the technical field of surgical navigation. The method comprises the following steps: before surgery, high-precision calibration of the system is performed by using an optical calibration method; and during surgery, a pose of a target object is measured by using a non-shielding mechanical positioning method. The non-shielding mechanical positioning method comprises the following steps: according to angles read by encoders at each joint in real time and a kinematic model obtained by using the optical calibration method before surgery, a transfer matrix of the object relative to a reference system is obtained, so that the relative position and attitude of the measured object are calculated. By using the processing scheme, the flexibility of the optical calibration and the accuracy of the mechanical positioning are combined, so that the cost is reduced, and the high absolute positioning precision of the surgery in a narrow space is ensured.

A navigation system is described that allows for absolute pointer positioning by integrating a lever that establishes the navigation and activation relationship of the pointer, similar to a mouse, but without the drawbacks of sequential positioning methods. This innovative system combines a lever, an infrared light emitter, a camera, and image processing software to locate the lever's position in two dimensions and synchronize this position with the mouse pointer. The lever moves on a spherical surface or ball joint, enabling precise and fluid navigation. The infrared light emitter and the camera work together to establish the pointer's position, while image processing software allows the infrared emitter's position to be located in two dimensions and associated with the computer pointer's position.This approach offers absolute pointer positioning, improving the user experience in terms of accuracy and comfort.

The invention relates to the technical field of image processing, and discloses a monocular vision initialization method suitable for aerial images of an unmanned aerial vehicle, which comprises the following steps: taking an image currently shot by the unmanned aerial vehicle as a first key frame, selecting an image frame meeting a preset condition from images shot in the subsequent flight process of the unmanned aerial vehicle, and taking the image frame as a second key frame; obtaining all undetermined road sign points according to positioning information when the unmanned aerial vehicle shoots the first key frame and the second key frame, and obtaining a final road sign point according to reprojection pixel bases of all the undetermined road sign points on the first key frame and the second key frame and all the undetermined road sign points; and according to the matching result of the second key frame and the satellite map, obtaining the latitude and longitude coordinates of the final road sign point, and by taking the minimization of the re-projection error of the final road sign point as a target, constructing a least square problem to obtain an optimized parameter. According to the invention, absolute positioning can be realized on the monocular vision system.

A method and system for locating defects in cable-stayed bridges based on image recognition is disclosed, relating to general image data processing or generation. In this method, the spiral features of the cable-stayed bridge in consecutive video frames are extracted, and a sequence of equally spaced virtual nodes is generated by combining these features with a reference pixel spacing. The cumulative pixel displacement of the current frame is obtained by matching the translation differences between virtual nodes in adjacent frames. When a defect is identified, the intra-frame pixel offset of the defect relative to the first virtual node is calculated. Finally, the cumulative displacement and the intra-frame offset are added to obtain the total pixel coordinates of the defect, and calibration parameters are used to convert them into absolute positioning coordinates in physical space. This application aims to suppress missed and false detections during image feature extraction, reduce accumulated errors in visual distance calculation, and thus improve the accuracy of locating cable-stayed bridge defects in physical space.

The application discloses a kind of mechanical arm error compensation methods based on geometric error and non-geometric error combination, belong to mechanical arm precision control field.The present application mainly includes two parts of geometric error parameter error compensation based on least square algorithm and non-geometric error compensation based on BP neural network;In the geometric error compensation stage, the mechanical arm geometric error model is established by MDH method, then least square algorithm is designed to solve error model to obtain geometric error model data;In the non-geometric error compensation stage, the non-geometric error model based on BP neural network algorithm is designed to adaptively predict position and attitude compensation data;Geometric and non-geometric error compensation data are combined to compensate the positioning error of mechanical arm.The comprehensive error compensation method of the application can efficiently realize the high-precision error compensation of six-degree-of-freedom mechanical arm, and improve the absolute positioning accuracy of six-degree-of-freedom mechanical arm.

The invention discloses a pointer reset method and system based on UWB absolute positioning, and the method comprises the following steps: S1, obtaining the original positioning data of a current UWB in real time when a reset key is triggered, and calculating the absolute coordinates (Xcurrent, Ycurrent); s2, reading a target coordinate (Xtarget, Ytarget) from a preset configuration, and calculating a deviation ([delta] X, [delta] Y); and S3, inputting the deviation (delta X, delta Y) as an initial offset into a correction algorithm to correct the real coordinates (Xraw, Yraw), and gradually correcting the real coordinates (Xraw, Yraw) through the correction algorithm in sequence until the residual deviation (delta X remain, delta Y remain) returns to zero. According to the method, the deviation value is gradually fused into the subsequent real coordinate data stream through the correction algorithm, and the screen pointer can be intelligently and smoothly reset to the preset specified position from the current position quickly and naturally only through a single instruction.

The invention discloses a container real-time monitoring method based on the satellite internet, and relates to the technical field of container satellite positioning. An autonomous node is arranged in each container, and a dual-mode communication system is constructed through industrial internet satellite short message communication and UWB near-field grid communication. When satellite signals are normal, data are directly uploaded, and when the satellite signals are blocked, the data are converged to edge nodes for uplink through a multi-hop UWB link. Through a calculation mechanism combining relative positioning and absolute positioning, continuous position calculation in a satellite failure environment is realized. A controllable electromagnetic metamaterial unit is arranged on the surface of the autonomous node, and zero active radio frequency power consumption communication is achieved in a passive echo modulation mode. And in combination with a hierarchical grid structure and a dynamic edge node election mechanism as well as an energy collection and deep dormancy control strategy, low-power-consumption, continuous and anti-blocking real-time monitoring in a global environment is realized.

The present application belongs to the field of airborne photoelectric reconnaissance and situation awareness, and discloses a kind of integrated visual scene generation method based on photoelectric video motion estimation, comprising the following steps: determining the visual scene geographic range according to the photoelectric starting point position;For adjacent frames of photoelectric image, feature point extraction and matching are carried out;For the starting geographic area of photoelectric image, select the integrated visual scene geographic area and the corresponding photoelectric image for matching;According to the matching feature point pair of adjacent frames, the relative motion rotation matrix and translation matrix are solved;According to the matching result, the absolute positioning result of the carrier is solved;Fusion absolute positioning and relative positioning result, form continuous positioning result output;Establish a virtual camera imaging model;Based on virtual camera, integrated visual scene is generated.The present application can meet the integrated visual scene generation ability of existing airborne equipment under certain degree of anti-interference condition, and can be applied in multiple airborne task scenes by designing special software module, to help realize high-precision matching ability between multiple modal images.

The industrial robot absolute positioning error compensation method solves the problems of weak normal observation and unstable pose estimation under long distance or inclined angle in the existing robot absolute positioning, and belongs to the technical field of industrial robot precision control. The present application comprises: constructing a multi-layer parallel ArUco marker field in the workspace and optimizing the layout; the robot end monocular camera collects the marker field image along the planned path, and the enhanced image is obtained through edge-ROI guided super-resolution reconstruction; corner detection and pose solution are carried out based on the enhanced image, the actual pose is obtained and compared with the theoretical pose to obtain the pose error, and the re-projection error is recorded, and the data set is composed of the robot state characteristics; the data set is used to train the heteroscedastic Gaussian process regression model, wherein the observation noise variance of each sample is proportional to the square of the re-projection error; for the target task path point, the state characteristics are input into the model to predict the pose error and compensate to the theoretical instruction to generate the modified control instruction.

The invention relates to the technical field of computer vision and positioning, in particular to a tight coupling method for vision relative positioning and absolute positioning. The technical problems that in the application process of a visual positioning method in the prior art, the visual positioning method depends on a holder, information utilization is insufficient, and the adaptive capacity is poor are solved. According to the technical scheme, the tight coupling method for visual relative positioning and absolute positioning comprises a visual relative positioning step, a reference image obtaining step, a real-time image preprocessing step, a feature matching step and an optimization step, in the feature matching step, feature matching is conducted on a preprocessed real-time image and a reference image, a homography matrix is calculated, and the real-time image and the reference image are optimized; mapping feature points on the real-time image to a world coordinate system in the visual relative positioning step; according to the method, visual absolute positioning and relative positioning are tightly coupled under a factor graph framework, and meanwhile, position, attitude and scale parameters are optimized, so that high-precision and high-robustness positioning is realized.

A method includes receiving a two-dimensional (2D) image captured by a camera on a unmanned aerial vehicle (UAV) and representative of an environment of the UAV. The method further includes applying a trained machine learning model to the 2D image to produce a semantic image of the environment and a depth image of the environment, where the semantic image comprises one or more semantic labels. The method additionally includes retrieving reference depth data representative of the environment, wherein the reference depth data includes reference semantic labels. The method also includes aligning the depth image of the environment with the reference depth data representative of the environment to determine a location of the UAV in the environment, where the aligning associates the one or more semantic labels from the semantic image with the reference semantic labels from the reference depth data.

The invention discloses a calibration method for improving absolute positioning precision of a robot by adopting visual image processing, and belongs to the field of industrial robot calibration. Firstly, a three-dimensional measurement model of stereoscopic binocular vision is constructed to obtain point cloud; constructing a robot standard working pose point cloud model and a real working pose point cloud model; and optimizing the point cloud model by adopting an improved point cloud denoising algorithm. And secondly, according to an error between the two point cloud models, a space offset equation of a connecting rod is obtained through calculation, so that tail end offset of the robot caused by a working environment and a load is compensated. Compared with a robot calibration method based on an RGB image, the method can avoid the problem of depth information loss caused by two-dimensional projection, and the calibration precision is remarkably improved.

The application discloses a table virtual scrolling method and system, which comprises providing a root element, setting a scrolling container and a display container in the root element, and the two containers are sibling nodes in the same DOM level; the two containers are fixed in the root element through absolute positioning, and the display container is visually displayed on the scrolling container; the display container is fixed in the visible area and does not produce position deviation with the scrolling of the scrolling container; horizontal and vertical absolute positioning coordinates are set for each cell in the display container, and the final display position of all cells in the table is determined through absolute positioning; the scrolling container is used as the only node for executing the scrolling operation, and the scrolling displacement is generated by the scrolling container; the starting index and the ending index of the current visible area are calculated in real time according to the scrolling displacement, only the cells in the index range are rendered, and the cells outside the visible area are not rendered; the performance bottleneck of the white screen during fast scrolling, the synchronous misplacement of fixed columns and too many horizontal columns is overcome.

This invention belongs to the field of industrial robot-assisted manufacturing and precision operation technology, and discloses a method and device for precision micro-operation of industrial robots. The method includes: establishing a robot differential kinematic error model coupled to a tool coordinate system; automatically acquiring data on the robot's end-effector pose and corresponding robot joints using a low-cost probe and planar calibration block; constructing and solving a set of error identification equations including tool errors to obtain a corrected robot kinematic model; proposing a virtual tool coordinate algorithm to convert the calibration results for the probe into actual target point control of the micro-operation actuator; and using the corrected robot kinematic model and its corresponding compensation program to control the robot to complete high-precision micro-operations. This invention can improve the absolute positioning accuracy of robots from hundreds of micrometers to tens of micrometers, and is low-cost and highly automated, showing broad application prospects in the field of robot-assisted precision micro-operations.

The invention discloses a first-stage deep coupling positioning system based on a GNSS original signal and a laser radar point cloud. The first-stage deep coupling positioning system comprises an IMU module used for obtaining data of an inertial measurement unit; the laser radar module is used for acquiring laser radar point cloud data; a GNSS receiver module for receiving original global navigation satellite system observation data, the original GNSS observation data comprising a pseudo-range observation value and a carrier phase observation value; and the data processing unit is in communication connection with the IMU module, the laser radar module and the GNSS receiver module. According to the invention, by introducing a carrier phase double-difference residual factor, when a GNSS signal is available, a strong geometric constraint with centimeter-level precision is provided for the system, and the absolute positioning precision is greatly improved; when the GNSS signal is partially or completely invalid, the IMU and laser radar factors can maintain the relative positioning and short-term precision of the system, and seamless degradation and recovery are realized; the method is suitable for complex scenes such as urban canyons, avenues and viaducts.

The invention discloses a positioning method and system based on an ultra wide band technology and an inertial measurement unit. The method comprises the following steps: receiving first position acquisition data of a target person and second position acquisition data of target equipment sent by a positioning device in a power construction site; performing fusion processing on first ultra wide band (UWB) ranging data and first IMU inertial data in the first position acquisition data to obtain first positioning data of the target person; performing fusion processing on second ultra wide band (UWB) ranging data and second IMU inertial data in the second position acquisition data to obtain second positioning data of the target equipment; and determining a target positioning result according to the first positioning data of the target person and the second positioning data of the target device. According to the method, the UWB absolute positioning precision and the IMU short-time high-precision characteristic are combined, three-dimensional centimeter-level positioning is achieved in a complex construction environment, in the non-line-of-sight environment that UWB signals are temporarily shielded, the IMU can provide continuous positioning capacity, and the blind area problem of the UWB technology is effectively solved.

The absolute position of a car is captured with high accuracy by compensating for errors in an absolute positioning system with a configuration that has been improved in terms of placement and installation. An elevator system with an absolute positioning system (APS) that captures absolute position information corresponding to the absolute position of a car in a direction of motion comprises: a capture target object fixed in an elevator shaft; and a capture target object capture device attached to the car. A value learned through pre-training as the absolute position corresponding to a reference position of the capture target object in the direction of motion is pre-stored in a memory device.A control device acquires the absolute position information and the movement speed information of the cabin at the time when the acquisition target object acquisition device acquires an end section of the acquisition target object while the cabin is moving, calculates an absolute position calculation value of the reference position based on the acquired information and compensates for the absolute position information acquired by the APS based on a comparison between the learned value stored in the storage device and the calculated absolute position calculation value.

The utility model relates to the technical field of navigational positioning devices, in particular to an integrated navigational positioning device which comprises an integrated navigational positioning device body, a charging port comprising a contactor, a guide ring, a cable joint groove, a first inclined plane bump and a first spring, and a locking mechanism comprising a frame body, a mounting plate, a rotating shaft, a first roller and a second roller. The locking mechanism is provided with a second inclined plane convex block, and the second inclined plane convex block is matched with the inclined plane push rod to control the locking mechanism to move; the first inclined plane protruding block is matched with the locking mechanism, and the locking mechanism locks the cable connector of the charging line in the process that the plug is inserted into the charging port, so that charging failure caused by the fact that the plug is separated from the charging port or is in poor contact with a contactor in the charging process is prevented. By arranging a second spring, a second inclined plane convex block and an inclined plane push rod, non-absolute positioning is provided for the locking mechanism through the second spring, so that the locking mechanism can be adapted to cable joints with different sizes while the locking mechanism has certain locking capability.

The invention provides a crowdsourcing map data processing method, a crowdsourcing map data processing device and related equipment, and relates to map data processing technology applied to the field of vehicles, and the method comprises the following steps: in response to a vehicle entering a parking area, acquiring relative positioning information, absolute positioning information and geographic space data of the vehicle in a vehicle driving process; determining a plurality of key frames based on the relative positioning information; the difference values between the relative positioning of the vehicles corresponding to any two adjacent key frames are the same; extracting and corresponding the absolute positioning information and the geographic space data based on the timestamp information of the key frames, and determining the absolute positioning information and the geographic space data corresponding to each key frame; generating crowdsourcing map data according to the timestamp information of the key frame and the absolute positioning information and geographic space data corresponding to the key frame; and uploading the crowdsourcing map data to a cloud. According to the invention, it can be ensured that the vehicle uploads a small amount of data, does not occupy resources and traffic of the vehicle using end, and also ensures that the cloud can generate an accurate map.

This application provides a robotic arm grasping control method, system, device, and electronic device. In this embodiment, the grasping motion of the gripper is controlled by utilizing the position of the target object and the gripper in the camera coordinate system, and the grasping direction angle of the target object and the direction angle of the gripper in the image coordinate system, thereby achieving grasping control in the camera-dependent coordinate system. This eliminates the need for coordinate transformation between the camera's extrinsic parameter matrix and the robotic arm's base coordinate system, thus reducing the requirements for camera accuracy and the absolute positioning accuracy of the robotic arm. Furthermore, by performing grasping control only in the camera-dependent coordinate system, without needing coordinate transformation between the camera's extrinsic parameter matrix and the robotic arm's base coordinate system, the problem of grasping failure due to insufficient absolute positioning accuracy of the camera and robotic arm is avoided.

The present application relates to the technical field of building area three-dimensional model construction, in particular to a three-dimensional model construction method, system, device and medium based on unmanned aerial vehicle surveying and mapping; the method of the present application firstly performs pixel-level segmentation on the building area images obtained by the unmanned aerial vehicle to obtain ground object categories, and further segmentation is performed in combination with terrain information to obtain scene units; then, the scene unit point cloud data obtained by each unmanned aerial vehicle is registered within the unit, and combined with an absolute positioning reference, inter-unit registration processing is performed, and then through curved surface reconstruction and boundary fusion, a three-dimensional point cloud model is obtained; finally, through obtaining a multi-angle RGB image set of each scene unit, visible image extraction is performed, occlusion interference is removed, the best view image is selected to reduce texture deformation, and finally the texture of the best view image is mapped to the three-dimensional point cloud model to obtain a surveying and mapping area three-dimensional model, which has accurate geometric structure and high-fidelity visual features, and provides high-precision and real three-dimensional basic data for surveying and mapping visualization, engineering design and the like.