Abstract: A positioning method, which relates to the positioning field and is applied to target positioning in a spatially overlapping scenario, is disclosed. The positioning method can avoid a positioning error in the spatially overlapping scenario. The method includes: constructing a local topology map of a target at a current moment based on identifiers of segments and one or more connection relationships among at least some of the segments, wherein the identifiers of the segments and the one or more connection relationships are prestored in map information; and determining, by using the local topology map, a specific road segment in which a target located in a spatially overlapping region is located at a next moment. In addition, a positioning map linked with a road segment may be further stored in the map information, and a positioning map linked with a positioned road segment is determined based on the positioned road segment, to implement high-precision positioning.

Abstract: Systems and methods of visual simultaneous localization and mapping (SLAM) based on point and line features are disclosed. The method includes: receiving a visual image frame input by a camera device; extracting feature points and feature lines from the visual image frame; predicting a first pose of the camera device using the feature points; observing an extracted first feature line to determine a feature line measurement of the first feature line; obtaining a global feature line state vector set of the camera device, where the global feature line state vector set includes feature line state vectors of N historical feature lines, and N is a positive integer; and updating the first pose using the feature line measurement and the global feature line state vector set. In this way, feature point-based motion estimations and observation features of feature lines observed in an environment are integrated to update a pose of the camera device in real time, thereby improving visual SLAM accuracy.

Abstract: This disclosure provides a moving object tracking method and apparatus. The method includes: obtaining a current frame captured by a camera; predicting a current state vector of the camera based on an inertial measurement unit IMU and the current frame, to obtain a predicted value of the current state vector of the camera; predicting a current state vector of a target object that is moving in the current frame, to obtain a predicted value of the current state vector of the target object; and updating a Kalman state vector based on a measurement result of an image feature in the current frame. According to technical solutions provided in this disclosure, a target object that is moving in a surrounding environment can be tracked and a pose of the target object can be estimated while a pose of a system can be estimated.

Abstract: The low profile screw base comprises a screw base body and a positioning compression ring. An assembly hole penetrates longitudinally through the screw base body. A U-shaped slot for a connecting rod to pass through is provided on an upper portion of the screw base body. The inner wall of the screw base body on the opposite sides of the U-shaped slot is provided with internal threads. Snapping protrusions are formed on the inner wall of the screw base body on the opposite sides of the U-shaped slot below the internal threads. A lower ball socket matched with the round head of the ball screw is arranged in the assembly hole of the lower portion of the screw base body. The positioning compression ring used for compressing the round head is snap fitted above the lower ball socket and below the snapping protrusions (6).

Abstract: The method is: receiving a visual image frame input by a camera; extracting feature points and feature lines of the visual image frame; predicting a first pose of the camera device by using the feature points; observing an extracted first feature line, to determine a feature line measurement of the first feature line; obtaining a global feature line state vector set of the camera device, where the global feature line state vector set includes feature line state vectors of N historical feature lines, and N is a positive integer; and updating the first pose by using the feature line measurement and the global feature line state vector set. In this way, feature point-based motion estimations and observation features of feature lines observed in an environment are integrated, to update a pose of the camera device in real time, thereby improving visual SLAM accuracy.

Abstract: A grasping end of a frog-style forceps relates to the technical field of medical instrument for spinal surgery, and comprises a grasping end tube and a pressing-rod sleeve. The pressing-rod sleeve is sleeved over the grasping end tube. Two opposite strip-shaped openings are axially provided on a side wall of the grasping end tube. Positioning spring sheets are disposed inside the strip-shaped openings. Positioning protrusions are disposed on inner sides of lower end portions of the two positioning spring sheets inside the strip-shaped openings at a lower portion of the grasping end tube. A position limiting protrusion is disposed inside the lower portion of the grasping end tube. The grasping end for a frog-style forceps does not need to align relatively small positioning protrusions with a slot on a screw seat, so that it is convenient and easy to assemble and very easy to dismantle the grasping end.

Abstract: A uniplanar pedicle screw comprises a screw base, a positioning compression ring and a ball-head screw. Lateral bosses are provided at left and right sides of an upper portion of a ball head of the ball-head screw, and upper side surfaces of the lateral bosses are arc-shaped and project upwards. A central boss is provided on the ball head of the ball-head screw between the two lateral bosses, and an upper side surface of the central boss is arc-shaped and protrudes upwards. An arc center of the central boss and a connecting line of arc centers of the two lateral bosses are on the same straight line. Arc-shaped concave surfaces matching the two lateral bosses are provided at a lower portion of the positioning compression ring and at left and right sides of a rod accommodating groove.

Abstract: The low profile screw base comprises a screw base body and a positioning compression ring. An assembly hole penetrates longitudinally through the screw base body. A U-shaped slot for a connecting rod to pass through is provided on an upper portion of the screw base body. The inner wall of the screw base body on the opposite sides of the U-shaped slot is provided with internal threads. Snapping protrusions are formed on the inner wall of the screw base body on the opposite sides of the U-shaped slot below the internal threads. A lower ball socket matched with the round head of the ball screw is arranged in the assembly hole of the lower portion of the screw base body. The positioning compression ring used for compressing the round head is snap fitted above the lower ball socket and below the snapping protrusions (6).