246results about How to "Meet the positioning needs" patented technology

The invention relates to an unmanned vehicle real-time positioning method based on laser reflection strength. The method comprises the following steps of S1, photographing two sides of a city road by an on-vehicle laser radar, obtaining a plurality of frames of point cloud data, extracting road edge points and converting the road edge points into a current vehicle coordinate system; S2, selecting the road edge points of which the z-axis coordinate value is in a preset range and obtaining coordinates of the road edge points in a GPS coordinate system, using the current GPS coordinate point of the unmanned vehicle as an original point, dividing a coordinate space for obtaining a grid map; S3, matching the gridded high-precision map with the grid map which is obtained in the step S2, thereby obtaining position of the unmanned vehicle on a high-precision map; and S4, predicating vehicle posture by means of a Kalman filter. Compared with prior art, the unmanned vehicle real-time positioning method can realize real-time accurate positioning in a complicated environment and can effectively improve driving safety of the unmanned aerial vehicle.

The invention relates to the technical field of navigation positioning, particularly to a navigation positioning technique based on multi-sensor data fusion. A GPS aided positioning system based on multi-sensor data fusion comprises a GPS navigation system, a gyroscope and accelerometer combined system, a data processing and fusion module and a map-matching module, wherein the GPS navigation system comprises a GPS module and a data collecting and processing module thereof and is used for acquiring the data of a carrier, such as GPS position, speed, time, number of satellites, and the degree of position accuracy; the gyroscope and accelerometer combined system comprises a gyroscope, an accelerometer and a data collecting and processing module and is used for acquiring the angular velocity,the speed and the accelerated speed of the carrier; the data processing and fusion module integrates the data acquired by the GPS navigation system and the gyroscope and accelerometer combined systemso as to obtain the position information of the carrier; and the map-matching module corrects the error of position information of the carrier outputted by a digital electronic map and the data processing and fusion module so as to obtain the final position information of the carrier. The invention also provides a GPS aided positioning method based on multi-sensor data fusion.

The invention discloses a method for constructing an electronic map locating database, comprising the following steps of: simultaneously collecting ID information of a plurality of wireless equipment on a plurality of different geographic coordinates; uploading the collected ID information of the plurality of wireless equipment and the geographic coordinates to a server; solving a position coordinate corresponding to each ID according to the ID information of the plurality of wireless equipment and the geographic coordinates; and integrating each ID and the position coordinate corresponding to the ID to form a locating database. With the method, a plurality of CELL IDs of a plurality of base states and / or a plurality of MAC (Multi-Access-Computer) addresses of a plurality of WIFIs (Wireless Fidelity) on a same location can be simultaneously collected through a mobile communication terminal, the plurality of CELL IDs and / or the plurality of MAC addresses can be uploaded to a back-end server for operation and the plurality of CELL IDs and / or the plurality of MAC addresses with a plurality of corresponding position coordinates are bound to form the electronic map locating database, thereby higher collection efficiency and shorter collection data period are realized and the electronic map locating database can be established to conveniently provide location service to a user in a plurality of modes and satisfy the location needs under various conditions.

The invention discloses a method for achieving classification positioning by a mobile monitoring terminal. The mobile monitoring terminal comprises a detection module, a communication module, a positioning module and a height sensor, the positioning module conducts classification positioning, dynamic positioning configuration is adopted in the monitoring terminal, the positioning module comprises a wide area positioning module and an RF local area positioning module, the wide area positioning module is based on satellite GPS tracking positioning or a mobile cellular base station or an LBS tracking positioning system or a GPSONE tracking positioning mode, the RF local area positioning module is based on a WiFi or a Zigbee or a Bluetooth or a UWB, the wide area positioning module is in the continuous working state all the time, when the monitoring terminal enters the local area positioning network range, the local area positioning module is started so as to timely send RF beacons at intervals with the set RF signals, and when the monitoring target is away from the local area positioning network range, a monitoring center turns off the local area positioning module of the terminal. The method has the advantages of being accurate in positioning, wide in coverage, high in intellectualization and cruising ability and the like.

This invention discloses a method for locating mobile terminal by distribution-type antenna, belonging to CDMA technology field, which via net actualizes the measurement of location parameter and calculation of mobile terminal position, comprising the steps: a, base station calculates at least three antenna time interval from upward special physics channel signal of terminal to base station control; b, based on the time interval and distances between the station and antenna, calculating the distance between mobile terminal and antenna; c, determining a hyperbola between every two antennas; d, evaluating the terminal position based on no less than two hyperbola convergence area. The invention has the advantages of lower cost, higher efficiency, accurate location and ease of actualization.

The invention provides a locating control method, device and terminal. The method comprises the following steps: acquiring motion state parameters corresponding to a terminal to be located after receiving a locating request; judging whether the motion state parameters meet a pre-set locating condition or not; prohibiting start of GPS locating when the motion state parameters do not meet the pre-set locating condition. According to the embodiment of the invention, the motion state parameters corresponding to the terminal to be located are acquired before start of GPS locating, whether the motion state parameters meet the pre-set locating condition or not is judged, and start of GPS locating is prohibited when the motion state parameters do not meet the pre-set locating condition, so that repeated invalid GPS locating can be avoided effectively. Therefore, electricity consumption caused by GPS locating can be reduced, and the standby time of a corresponding device is prolonged.

The invention discloses an alternating magnetic field guiding device. The alternating magnetic field guiding device comprises a near-bit manual magnetic pole module, a destination module and a source control module, wherein the near-bit manual magnetic pole module transmits a low-frequency alternating magnetic field signal; the destination module acquires the low-frequency alternating magnetic field signal and calculates the relative azimuth and distance between a bit and a destination target point; the information of the relative azimuth and distance is transmitted to a driller indication control unit of the source control module by a remote transmission unit; and the driller indication control unit adjusts the drilling direction of the bit in real time according to the received information of the relative azimuth and distance between the bit and the destination target point, so the bit is controlled to accurately drill toward the destination target point. The alternating magnetic field guiding device breaks through the conventional open-loop control mode depending on the measurement result of the near-bit azimuth angle of the source, and improves the accuracy of controlling the bit to drill toward the destination target point in real time by measuring the information of the relative azimuth and distance between the bit and the destination target point and taking the relative azimuth and distance between the bit and the destination target point as the closed-loop control parameters.

The invention discloses a water-saving irrigation monitoring network location method based on RSSI ranging. The method comprises the following steps of S1, rapidly acquiring distance information of a monitoring node by using signal propagation and modeling; S2, acquiring relative error coefficients of anchor nodes by comparing measured distances between the anchor nodes with actual distances and acquiring differences, so as to correct measured distances between the monitoring node and the anchor nodes in a communication range of the monitoring node; S3, computing a coordinate of the monitoring node by using a ranging weighted centroid location algorithm; and S4, correcting the coordinate of the monitoring node. The method fully considers influences of RSSI ranging errors and the quantity of the anchor nodes on the location accuracy, so that a good location effect can be achieved, and the location requirement of a large farmland irrigated area soil moisture content monitoring system with bad network environment and limited location cost can be met, and compared with a common L basic location algorithm, the method of the invention has higher location accuracy and lower computation complexity.

The invention relates to a positioning system of an electric vehicle reverse charging pantograph online charging device and an adjusting method. The positioning system comprises a vehicle-mounted portion and a platform portion. The vehicle-mounted portion and the platform portion are connected in a wireless communication mode. The platform portion comprises a platform positioning controller, a wireless module, three motors, two positioning sensors, a transverse plate and a vertical rod. The vehicle-mounted portion comprises a vehicle-mounted positioning controller, a vehicle-mounted wireless module, a positioning operation and indication device and a positioning inductive sensor, wherein all the components are installed on a vehicle. The platform type reverse charging pantograph online charging device comprises a reverse charging pantograph installed on a platform and a charging pole plate installed on the top of the vehicle. After the vehicle enters the platform and positioning is accurate, the reverse charging pantograph is lowered down to compress the charging pole plate to begin to rapidly charge the vehicle; after charging is completed, the reverse pantograph is folded and retracted. The purpose of online charging positioning of the platform type reverse charging pantograph is effectively achieved, and the positioning system is generally applicable to vehicles of different models.

The invention discloses an inland river hydrological and water administrative ship real-time location monitoring system. The system comprises a satellite system (1), a terminal equipment system (2) and a background monitoring system (3). The real-time location monitoring system can realize real-time communication and location monitoring of the terminal equipment system (2) and the background monitoring system (3) through the satellite system (1). The invention further discloses an inland river hydrological and water administrative ship real-time location monitoring method. Through cooperation with an inland river sand excavation management method, the ideas that an early warning buffer zone with the width of 50 meters is established and the ship navigation line measurement allowable deviation range is displayed in two modes are put forward in the method for the first time, the early warning buffer zone and the line measurement allowable deviation range are displayed in a GIS visualized dynamic monitoring application platform of the background monitoring system (3), and the information recording precision can be measured in seconds. Through the inland river hydrological and water administrative ship real-time location monitoring system and method, the functions of locating and tracking, boundary violation alarm, monitoring and dispatching, yawing warning and trajectory analysis on monitored ships are achieved.

The invention discloses a multi-degree of freedom piezoelectric stick-slip micronano positioning platform and a driving method thereof. By the multi-degree of freedom piezoelectric stick-slip micronano positioning platform, the technical problems of small moving range, low accuracy, control complexity and the like of an existing multi-degree of freedom moving platform are solved. The multi-degreeof freedom piezoelectric stick-slip micronano positioning platform comprises an x-direction driving assembly, a y-direction driving assembly, a Theta z rotation assembly, an upper shell and a connection screw. A displacement conversion mechanism generates an oblique force by telescopic deformation of a piezoelectric stack, and a rotor is further driven to move; when the piezoelectric stack stretches, the friction driving force between the rotor and a stator can be increased; and when the piezoelectric stack contracts, the friction resistance between the rotor and the stator can be reduced. Themulti-degree of freedom piezoelectric stick-slip micronano positioning platform has the advantages of large range and high accuracy, is simple and convenient to control and has wide application prospect in the high-end technical field of spatial mechanisms, life sciences, optical precise instrument and superfinishing.

The invention discloses a heating device for a Hopkinson pressure bar test, which comprises a movable supporting platform, a tubular heating furnace and an electric control box. The tubular heating furnace is mounted on a sliding plate of the movable supporting platform. Two groups of sliding rails and a plurality of fixed sliding beads are arranged on the upper surface of the sliding plate. Two alundum tubes are symmetrically sleeved at two ends of a heat-resistant steel tube. Heat-resistant bricks are respectively built around the external surfaces of the joints of the two alundum tubes and the heat-resistant steel tube. The heat-resistant bricks are provided with through holes for mounting silicon carbide rods. Insulating linings are sleeved on the external surfaces of a hearth and the heat-resistant bricks. Positions where inner cavities of the insulating linings correspond to the through holes on the heat-resistant bricks are all provided with mounting holes of the silicon carbide rods. Aluminum silicate fibrous carpets package the external surfaces of the insulating linings. A furnace shell is packaged on the external surfaces of the aluminum silicate fibrous carpets and the insulating linings. A base is fixed on the furnace shell. Two heat-insulating covers are respectively mounted in the hearth from hearths at two ends, and end cover bolts are fixed at two ends of the furnace shell. In the invention, the tubular heating furnace can move in the up-and-down direction, the leftward-rightward direction and the frontward-backward direction of the platform, and the heating device has the characteristics of good heat-insulating performance and convenience in repair.

The invention provides a locating method of a mobile terminal and a mobile location center, used for realizing location of the mobile terminal in a packet data field; the method comprises the following steps: step1, the mobile location center and a wireless network controller carry out synchronization of base station data; step 2, an application program module of the mobile terminal updates cell set information and transmits the cell set information to the mobile location center through a gateway general packet radio service support node GGSN element location in the packet data field; step 3, the mobile location center calculates location information of the mobile terminal according to the cell set information and the base station data. The invention does not relate to a control field element location of a mobile communication network, thus facilitating the location service to be conveniently developed with lower cost and solving the technical problems of high cost of the prior art and great influence on the existing network.

The invention relates to a vertical full-annular-direction positioning jig frame device system and construction technology for a large-diameter pile foundation reinforcement cage. The vertical full-annular-direction positioning jig frame device system comprises vertical positioning jig frames and a supporting jig frame, wherein the vertical positioning jig frames are installed on jig frame moving rails. According to the design and arrangement size of longitudinal ribs of the reinforcement cage, comb holes are formed in the vertical positioning jig frames and used for containing the longitudinal ribs of the reinforcement cage, moving sliding wheels capable of moving left and right in the direction of the cross section of the reinforcement cage are installed at the bottoms of the vertical positioning jig frames, the moving sliding wheels are installed on the jig frame moving rails, a fixed supporting clamp and a movable supporting clamp are arranged on the supporting jig frame and used for fixing stiffened stirrups, triangular supporting ribs are installed in the stiffened stirrups and used for improving the strength of the stiffened stirrups, and plate ribs of the reinforcement cage are fixedly installed on the longitudinal ribs of the reinforcement cage at a certain interval through binding wires. Due to the arrangement of the full-annular-direction movable jig frame device, the pile foundation reinforcement cage can be manufactured at a time, and the manufacturing efficiency of the reinforcement cage is greatly improved; besides, machining precision is high, speed is high, the jig frames can be repeatedly used, operation is convenient, and the vertical full-annular-direction positioning jig frame device system and construction technology are economical and fast to use.

The invention discloses a welding clamp set for a seat support. The welding clamp set is provided with a plurality of sets of rail structures and is matched with a plurality of sets of clamps, so thattubular parts with different specifications and bending shapes can be positioned. The clamps are adopt an adjustable structure, and the positioning requirements of the tubular parts with different thicknesses can be met; the production efficiency is improved, the production management is facilitated, and the additional cost caused by the fact that different clamps are manufactured to adapt to a machined seat is reduced, so that the adjusting which one clamp set is adopted by the metal tubular seat part positioning with small structural specification difference can be realized.

The invention discloses a flexible automatic loading system and application thereof. The flexible automatic loading system aims to solve the problems that an existing bagged material loading device lacks a corresponding automatic scanning and positioning system and is low in automatic degree. According to the flexible automatic loading system and the application thereof, mechanisms of the loadingsystem are subjected to completely-new optimization design, a carriage is subjected to automatic scanning positioning through a laser scanning positioning unit, a material is conveyed through a feeding unit, and through a stacking and loading unit, the material is effectively placed on a designated position of the carriage to achieve material automatic loading. The flexible automatic loading system can meet the demands of the sizes and height change of various material conveying vehicles, the loading path can be automatically planned according to the size information and loading tasks of a target vehicle carriage, automatic loading is achieved according to data provided by the laser scanning positioning unit, and in the whole loading process, only loading task manual issuing is needed. According to the flexible automatic loading system, the labor intensity of workers can be effectively reduced, the bad loading environment is avoided, the production efficiency of enterprises is improved, the labor cost of the enterprises is reduced, and the high application value is achieved.

The invention discloses an intelligent full-hydraulic power catwalk which comprises a supporting arm, a lifting leg, a pulley, a drill rod positioning mechanism, a plurality of active outriggers, a twisting machine, a twisting machine sliding rail, a control box, a ramp, outriggers, an overturning plate, a foundation support, a waterpower decoring device and a hydraulic station. The ramp is connected with the foundation support via a bolt, the twisting machine and the twisting machine sliding rail are mounted on one side of the foundation support, the waterpower decoring device is mounted on the twisting machine, the drill rod positioning mechanism and the overturning plate are arranged on the foundation support, the pulley is arranged on the supporting arm, the active outriggers are arranged on two sides of the foundation support, the hydraulic station supplies power to a system, and operation of the system is control by the control box. By the aid of the intelligent full-hydraulic power catwalk, processes including joint and throw rod connecting, hole bottom power connecting and disconnecting and water power rock coring can be integrated, twisting and water power decoring can be automatically finished without removal of a drill rod, technical requirements for drilling deep well coring are met, construction fields are greatly reduced, labor intensity is lowered, and working efficiency of a drilling system is improved. Since the power catwalk is fully hydraulically controlled, stepless speed change can be realized, transmission mechanism is simplified, and adaptability and reliability of the power catwalk are improved.

The invention belongs to a technology for forming a resin-base composite material, and relates to a die for integrally forming an I-shaped reinforcement composite material wall plate. The die comprises a contour die 1, positioning blocks 2, cross beams 3, reinforcement forming dies 4, low flange forming dies, and forming auxiliary dies 6. The cross beams 3 and the reinforcement forming dies a4 are positioned by the positioning blocks 2 on the contour die 1, and the upper flange contour surface accuracy and the axis position accuracy are guaranteed by controlling the position accuracy of the assembled cross beams 3 and reinforcement forming dies 4. The die can effectively guarantee the assembly coordination relationship between an upper flange contour surface of the I-shaped reinforcement composite material wall plate and a skin molded surface of the wall plate.

The invention discloses a three-dimensional high-precision map generation method and device which are used for solving the problems that an existing three-dimensional high-precision map generation method is high in cost and low in efficiency. The three-dimensional high-precision map generation method comprises: collecting environment information around a vehicle body in the moving process of a vehicle in real time, and the environment information comprising environment point cloud data; for each frame of environment point cloud data, executing the following operations: carrying out object detection and semantic segmentation on the environment point cloud data according to a preset neural network model, determining movable obstacle point cloud data, and removing the movable obstacle point cloud data from the environment point cloud data; carrying out point cloud registration on the environment point cloud data without the movable obstacle point cloud data and the stored environment point cloud data with the movable obstacle point cloud data removed in the previous frame according to a preset algorithm; and completing one-time incremental updating of the three-dimensional high-precision map according to the environment point cloud data subjected to the point cloud registration.

The invention provides an efficient cooperative positioning method applied to a mobile ad hoc network. The method includes the following steps that: step A, a corresponding reference node set is determined according to a current target node, and distance measurement communication with corresponding reference nodes is carried out; step B, a certain number of position estimation samples for the target node are generated randomly according to distance measurement values and a distance measurement error model; step C, the position estimation samples generated by each reference node are screened separately according to weighting values, a screened-out sample is adopted as the confidence of the target node in current iteration, the estimated position of the target node in the current iteration is calculated; and step D, whether the iteration process of the current target node converges or reaches a maximum number is judged, if the iteration process of the current target node converges, the current target node is adopted as a reference node of another target node to be positioned. With the efficient cooperative positioning method adopted, the convergence speed of the iteration process of the target node is high, and computation complexity is low, high positioning accuracy can be ensured.

The invention discloses a 3D four-wheel aligner with no car pushing required, comprising an image processing and analyzing general module, a vehicle position compensation module, a hardware parameter compensation module, two cameras and four target disks with regular patterns. The 3D four-wheel aligner with no car pushing required is capable of overcoming the defect that a 3D four-wheel aligner with car pushing required is complex in operation. A test can be carried out directly once the target disks are hung, with no car pushing required. The operation is very simple and the data is more accurate. In view of the characteristic that the 3D four-wheel aligner with car pushing required in the market is complex in cart pushing, the 3D four-wheel aligner with no car pushing required in the invention is capable of carrying out measurement directly once the target disks are installed, with no cart pushing required. The technology adopted in the 3D four-wheel aligner with no car pushing required in the invention is totally different from that of the 3D four-wheel aligner with car pushing required, wherein the 3D four-wheel aligner with car pushing required uses position change of the target disks before and after cart pushing to calculate vehicle four-wheel alignment data, while the 3D four-wheel aligner with no car pushing required in the invention uses space structure of the target disks to calculate the vehicle four-wheel alignment data.

The invention discloses a vehicle positioning optimization method, a vehicle positioning optimization device, equipment and a storage medium and belongs to the field of automatic driving and can alsobe applied to the field of autonomous parking. According to the embodiments of the invention, the method is applied to electronic equipment. A vehicle carries a fusion positioning system and a perception positioning system which are used for determining a fusion vehicle pose and a sensing lane line. The method comprises the following steps that: target positioning information associated with optimized positioning information is acquired, wherein the target positioning information is determined through the electronic equipment and at least one positioning system mounted on the vehicle; an optimization model about the optimized positioning information and the target positioning information is constructed according to a preset positioning approaching strategy; the target positioning information is inputted into the optimization model, and the optimized positioning information in the optimization model is solved, so that the optimized positioning information can be outputted; and if the optimized positioning information passes verification, the optimized positioning information is sent to the vehicle so as to control the vehicle to drive according to the optimized positioning information.

The invention relates to a mixed positioning system of bluetooth beacon and a satellite, which comprises a main controller, a bluetooth beacon positioning module and a satellite positioning module respectively connected with the main controller; the bluetooth beacon positioning module comprises a bluetooth beacon data read device and an arithmetic unit which are sequentially connected; and the main controller controls and manages the bluetooth beacon positioning module and the satellite positioning module. The positioning system uses the bluetooth beacon to support the positioning of a receiving end, can simultaneously make up the defects of the satellite positioning and the mobile base station positioning, and achieve the accurate positioning for covering the inside of building and up to the periphery of the building so as to meet application requirements of different positioning precisions and position service required by a covering area.

The invention discloses a terminal-to-terminal positioning method and system. The method comprises the following steps: a first terminal sends a positioning request message to a first positioning server, wherein the positioning request message carries the identity of a second terminal; and the first positioning server acquires the position information of the second terminal according to the identity. According to the technical scheme provided by the invention, terminal-to-terminal positioning can be realized, and the positioning requirements of users can be satisfied.

The invention discloses a target location and tracking system based on a low-frequency electromagnetic wave. The target location and tracking system comprises a transmitting terminal, a receiving terminal and a server, wherein the transmitting terminal is fixedly arranged at a specific position and is used for transmitting the low-frequency electromagnetic wave, the receiving terminal is fixedly arranged on a target and is used for receiving the low-frequency electromagnetic wave and figuring out the strength of the low-frequency electromagnetic wave through analogue-to-digital conversion, and the server figures out the distance between the transmitting terminal and the receiving terminal according the strength of the low-frequency electromagnetic wave transmitted by the transmitting terminal and the strength of the low-frequency electromagnetic wave received by the receiving terminal, combines the distance between the transmitting terminal and the receiving terminal with the position of the transmitting terminal, and locates and tracks the target. The invention further discloses a target location and tracking method based on the low-frequency electromagnetic wave. By means of the target location and tracking system and method based on the low-frequency electromagnetic wave, the problem that a traditional location system is inaccurate or even is out of work in location when barriers exist is solved, and a wide range of location requirement of the system can be met through a system expansion method.

The invention relates to a positioning application management method, which comprises the following steps of: simultaneously transmitting position service request messages to a positioning management application module by a plurality of application modules; comparing the priority level of each application module transmitting the position service request message; dispatching the application module with higher priority level to occupy a positioning chip first; and suspending positioning services of other application modules. The invention also relates to another positioning application management method, which comprises the following steps of: receiving position service requests transmitted by a plurality of application modules by the positioning management application module; sorting the position service requests transmitted by the application modules by a self positioning logic processor; adding the sorted position service requests into a positioning task sequence according to a sorting result; calling the positioning chip to sequentially execute the positioning task according to sorting of a positioning task queue; and after the positioning task is executed, returning the positioning result to each corresponding application module. According to the positioning application management method disclosed by the invention, the problem of contradiction of multiple applications of the positioning chip can be solved and the sharing of positioning capability and position data can be realized.

The present disclosure relates to a positioning method, a positioning server and a positioning system. The positioning method includes the following steps: receiving a wireless positioning coordinateof a moving object, and determining a visual sub-map to be matched in a visual map database according to the wireless positioning coordinate; and through the determined visual sub-map to be matched, obtaining a visual positioning coordinate corresponding to a current image of the moving object captured during wireless positioning to use as a positioning result. The visual sub-map to be matched isselected based on the wireless positioning coordinate, and the visual positioning coordinate is determined as the positioning result in the selected visual sub-map to be matched. The wireless positioning coordinate is used to reduce the amount of map data involved in the visual positioning process, thereby improving the accuracy and efficiency of the visual positioning process, hence meeting the positioning requirements of a larger site.

The invention discloses a precise centring die device for a prefabricated concrete structure grouting sleeve. The precise centring die comprises a slideway, two sets of steel frames, a sleeve positioning shaft roller, a protruding bar positioning shaft roller and fixing nuts. The two sets of steel frames are oppositely arranged on the prefabricated part production line slideway in a parallel manner. Each steel frame set comprises two side steel plates and a cross steel plate, wherein the cross steel plate is arranged between the two side steel plates, and the cross steel plate is provided with a plurality of rows of small holes. One end of the sleeve positioning shaft roller penetrates the small holes of the cross steel plate of one steel frame set and is fixed to the corresponding cross steel plate through the corresponding fixing nut, and the other end of the sleeve positioning shaft roller extends into the grouting sleeve. One end of the protruding bar positioning shaft roller penetrates the small hole of the cross plate of the other steel frame set and is fixed to the corresponding cross steel plate through the corresponding fixing nut, and the other end of the protruding bar positioning shaft roller is in a tubular shape and is inserted into a protruding bar. The precise centring die device can ensure centring of the prefabricated concrete unit sleeve and the protruding bar in a high-precision manner, the site construction difficulty is lowered, and the connection quality of the prefabricated concrete structure grouting sleeve is practically guaranteed.

The invention provides an indoor wireless terminal positioning accuracy ensuring and trajectory correcting method; firstly, initial positioning data are allowed to pass through a low-pass filter, so as to reduce the problem of relatively large trajectory fluctuation caused by positioning errors, and then based on line segment intersections or based on a grid symbol trajectory correcting method, positioning results located in an error region are corrected. Based on indoor structure map information, a related judging mechanism is combined for correcting positioning results of indoor walls, doors, windows and the like, so as to obtain an accurate positioning trajectory, and better serve the indoor positioning and navigation.