Abstract: A steering wheel structure for an omnidirectional mobile robot chassis is provided. The steering wheel structure can realize two degrees of freedom: the rudder rotation of the steering wheel rotation and the full free movement realized in the horizontal plane, it has the characteristics of a small size and a lower height. The wheel assembly realizes the movement of the steering wheel when it moves forward; the rudder assembly realizes the movement of the steering wheel when the steering wheel rotates, initializes the steering direction, and calibrates the rotation through the zero position sensor; the suspension assembly realizes the damping and buffering of the longitudinal motion of the steering wheel; the wiring assembly constrains the movement of various wires when the rudder rotates; the support plate is used for the connection and support of the wheel assembly and the wiring assembly with the rudder assembly.

Abstract: A zero-stiffness impact isolation device includes a shell, a half-hourglass-shaped boss, a sliding block, a spring, a motion guide assembly, and an inner core. Where the motion guide assembly includes a linear bearing fixed to the shell and the inner core and a corresponding sliding rod, and is divided into a transverse guide assembly and a longitudinal guide assembly. The spring is sleeved outside the sliding rod of the transverse motion guide assembly, and two ends of the spring are in contact with the sliding block and the inner core, respectively. When the device suffers from external impact load, the inner core and the separated object carry out a reciprocating motion, the sliding block is extruded by the half-hourglass-shaped boss to move side to side with respect to the inner core, and the spring provides elastic force to the sliding block in the process.

Abstract: Disclosed is a membrane oxygenator, comprising a housing, and a blood-oxygen exchange chamber arranged in the housing. A liquid inlet side of the housing is provided with at least two blood inlets, and a liquid outlet side of the housing is provided with at least two blood outlets. The liquid inlet side and the liquid outlet side are respectively located at either side of the housing. Projections of blood inlets at the liquid outlet side do not coincide with blood outlets. By designing the shape of the blood-oxygen exchange chamber, blood inlets and blood outlets, and a blood inlet porous baffle of the membrane oxygenator in a mode fits to the shape design of the blood-oxygen exchange chamber and blood inlets, the effects of evenly distributing the blood flow to enable full blood-gas exchange, relieving the blood stasis and the like are achieved, and thus reduce the clinical thrombosis risk.

Abstract: The present application relates to a multi-objective collaborative optimization approach for large-scale air traffic management, which belongs to the technical field of civil aviation management. The present application includes generating a delay time vector and a first delay time for each flight; grouping all the flights to get multiple flight groups based on the overlap of flight times; using a delay time vector of each flight in each flight group to generate a subspecies group, crossing each subspecies group to generate children in turn, obtaining a delay variable of each flight and make mutation, and after multiple evolutions, taking a solution as the second delay time of the corresponding flight, updating the first delay time of each flight to the second delay time, and the first delay time obtained after several cycles is used to control the departure time of the corresponding flight.

Abstract: Provided are a pressure difference sensor, and a manufacturing method and an application thereof. A manner of bonding three layers of wafers is adopted, and the sensor includes an upper structure, an intermediate structure and a lower structure. Each of the upper structure and the intermediate structure is manufactured by a silicon-on-insulator (SOI) wafer, the lower structure is manufactured by patterned doped intrinsic silicon; and a lead pad of each of the upper electrode, and the intermediate electrode and the lower electrode is located on a corresponding one of three-stepped steps at a side of the pressure difference sensor. Annular through holes are formed around the upper electrode and the lower electrode. A constant capacitance of a capacitance signal outputted by an upper capacitor of the sensor by extending an electric field line path of the constant capacitor part.

Abstract: Embodiments of the present disclosure provide a method, an apparatus, a device and a storage medium for pre-warning of aircraft flight threat evolution. The method includes: inputting historical threat situation data to an evolution model that has been trained to convergence to output each evolution mode corresponding to the historical threat situation data and a probability corresponding to the evolution mode; obtaining evolution trend data corresponding to the historical threat situation data according to the evolution mode and the probability; assigning a detection task to other aircraft within a preset range of a target aircraft according to a crowdsourcing strategy, and acquiring current actual flight threat information detected by the other aircraft according to the detection task; sending pre-warning information to a pre-warning device if the flight threat meets a pre-warning condition.

Abstract: A steering wheel suspension structure of an omnidirectional mobile robot includes a steering wheel connecting ring, a plurality of leaf spring connecting beams and a chassis mounting section. The steering wheel suspension structure is an integrated plate structure. The steering wheel connecting ring is connected with a steering wheel, and the chassis mounting section is connected with a robot chassis. The leaf spring connecting beam is connected with the steering wheel connecting ring and the chassis mounting section, and the leaf spring connecting beam is used as the main component of suspension deformation. The suspension structure is simple, easy to install, light in weight, less in space, and highly integrated with the steering wheel assembly. When the suspension is deformed by the force, it weakens the radial force and only has the displacement and force in the vertical direction, thus ensuring the handling performance of the chassis.

Abstract: A centrifugal impeller for a blood pump, and a blood pump are provided. The centrifugal impeller comprises a circular base plate, centrifugal blades, and a supporting structure. A through hole is formed in the middle of the base plate to form a secondary flow path. The centrifugal blades are arranged on the upper surface of the base plate, each centrifugal blade is a banana-shaped blade which is thick in middle and thin at both ends, and a wrap angle of each centrifugal blade is greater than or equal to 90°, and the centrifugal blades extend radially from the outer edge of the through hole to the periphery of the base plate. The supporting structure comprises a supporting shaft arranged at the center of the through hole and supporting blades, one end of each supporting blade is connected to the supporting shaft, and another end is connected to the base plate.

Abstract: A wheel structure with a built-in reducer and motor is provided. As the driving wheel in a rudder wheel, which has a high degree of integration and significantly reduces the overall height of the rudder wheel while maintaining high speed and acceleration. The wheel structure includes a wheel coupled to a reducer, a drive motor connected to the reducer, and the reducer.

Abstract: The present disclosure belongs to the field of petroleum engineering, and specifically relates to a subsea Christmas tree re-prediction method integrating Kalman filter and Bayesian network. The subsea Christmas tree re-prediction method integrating Kalman filter and Bayesian network includes three steps: digital twin model establishment, degradation process re-prediction model establishment, and remaining useful life calculation model establishment.

Abstract: A dynamic impedance imaging system includes a dynamic impedance imaging sensor, an impedance detection and flow rate measurement module and an electrical impedance tomography (EIT) instrument. The impedance detection and flow rate measurement module is configured to detect an abnormal particle flowing through the dynamic impedance imaging sensor to obtain a flow rate of the abnormal particle, and generate a synchronous trigger signal. The EIT instrument is configured to inject a sinusoidal excitation current into the dynamic impedance imaging sensor under the trigger of the synchronous trigger signal, perform multi-channel interleaved sampling for the abnormal particle according to the flow rate to acquire multi-channel sampled data, and calibrate the multi-channel sampled data to implement impedance tomography imaging for the abnormal particle.

Abstract: The embodiments of the present disclosure provide a gaze point calculation method, apparatus and device. The method includes: determining a 3D model of a first scene; obtaining a first panoramic image captured in the first scene, the first panoramic image includes a face image of a face; determining a spatial location of the face according to the first panoramic image; determining a gaze direction corresponding to the face according to the first panoramic image; and determining an eye gaze target according to the 3D model, the spatial location and the gaze direction. The accuracy of tracking the eye gaze in 3D model is improved.

Abstract: The present invention discloses a APNT service positioning and integrity monitoring method and system. The method includes the following steps: determining a positioning accuracy requirement in a target scene; when the positioning accuracy requirement is high-accuracy positioning, determining a position of an aircraft by adopting a combined positioning algorithm, and monitoring the integrity of a combined positioning by adopting a multi-solution separation mode; when the positioning accuracy requirement is low-accuracy positioning, judging whether the aircraft is a high-altitude user; if not, adopting an air-to-air positioning algorithm for a high-altitude user and a low-altitude user based on LDACS to determine the position of the aircraft, and adopting a least square residual method to monitor the integrity of the air-to-air positioning.

Abstract: The present disclosure relates to a high-precision and high-efficiency laser polishing method oriented to a large-size ultra-thin mask plate, and belongs to the technical field of advanced laser manufacturing. A high-precision and high-efficiency laser polishing technology is applied to the surface smoothness improvement of the large-size ultra-thin mask plate. The high-precision and high-efficiency laser polishing method specifically comprises the four following steps: step one, selecting and placing an ultra-thin invar alloy mask plate on a five-axis machining platform; step two, adopting a nanosecond continuous laser, and setting a laser incident angle; step three, setting N laser polishing areas; and step four, performing laser polishing continuous splicing. Compared with the prior art, the surface smoothness of the mask plate is improved, the polishing efficiency is high, the precision is high, and the influence on the geometrical characteristic size of the appearance of an original mask plate is low.

Abstract: A constellation configuration optimization method of a low earth orbit (LEO) satellite augmentation system for an ARAIM application includes: 1, traversing vertical protection levels after all subset solutions and fault modes under the condition that integrity risk and continuity risk are equally distributed, and determining the constraint conditions of LEO satellite constellation configuration parameters; 2, determining objective functions of LEO satellite constellation configuration parameters x1, x2, x3, x4, eliminating calculated values of abnormal vertical protection levels, and screening initial populations of the parameters x1, x2, x3, x4; 3, calculating fitness of the objective functions; 4, starting from a second generation population, merging a parent population with an offspring population to form a new offspring population; 5, performing local optimal selection on the new offspring population, screening out a maximum value of the objective functions as an optimal offspring, and repeating step 4 un

Abstract: The present invention proposes method of gaze estimation with 3D face reconstructing, which precisely reconstructs a 3D face to accurately calculate the gaze direction of the face. The present invention decomposes the gaze direction calculation task into two sub-tasks of gaze-aligned 3D face reconstruction, and gaze contact realized by rotation. First, a 3D morphable model is used to reconstruct a basic 3D face with a 2D reference face image as input. Then, shape adjustment is performed on the basic 3D face to obtain a shape-aligned 3D reconstructed face. Finally, a gaze-aligned 3D face is obtained by replacing the textures of the shape-aligned 3D face eye area. For the subtask of gaze contact, the present invention proposes a novel method for realizing gaze contact by rotating a 3D face, which does not depend on too many assumptions and can be widely used in the field of virtual reality.

Abstract: A computer-based airplane flight path planning method based on the pigeon-inspired optimization (PIO) algorithm includes steps of establishing an uncertainty prediction model, determining the path to be optimized, and obtaining an optimal path using the PIO algorithm for a flight controller onboard to execute. The PIO algorithm treats a pigeon flock as a scale-free network, applies map and compass operators to the scale-free network, and performs landmark operations to obtain the optimal path. The device that performs the path planning includes an access module for obtaining the regional environment information and a flight controller onboard the airplane. The flight controller includes a building module for setting up the trajectory prediction model including uncertainties; a determining module to determine the trajectories which need optimization; an optimization module, which uses the PIO algorithm to optimize the flight path; and a computer memory module.

Abstract: Disclosed is a light intensity signal transmitting device based on a high-speed LED array. The light intensity signal transmitting device includes an LED array and a control board card; through a novel arrangement and driving mode, the LED array has a high-speed modulation characteristic and can transmit high-bit light intensity information at the switching speed of single-point LEDs; the control board card performs high-speed display by gating an I/O port of the LED array, and is used as a light intensity signal transmitting end to transmit a light signal. According to the light intensity signal transmitting device, on the premise that the switching rate of the LED array is ensured, multi-bit binary data transmission is realized, and the transmission rate is improved.

Abstract: A sensorless commutation error compensation system for a brushless motor, comprises: a brushless motor (200) and a commutation logic module circuit (100). The commutation logic module circuit (100) is connected to three virtual Hall signal output ends of the brushless motor (200), and used for receiving three virtual Hall signals output by the brushless motor (200), obtaining three error compensation angle signals on the basis of the three virtual Hall signals, respectively superimposing the three error compensation angle signals and the three virtual Hall signals to form superposition results, and controlling the brushless motor (200) to adjust commutation timing on the basis of the superposition results, so as to achieve commutation error compensation.

Abstract: This disclosure provides a cooperative path planning method and device for automatic control aerocraft and aerocraft system. The method includes: determining the current evaluation index of each selected point according to its current position, the target position of the aerocraft and the position of obstacles in the selected area; updating the adjustment displacement of each selected point according to its adjustment displacement, current position and historical optimal position, as well as the global optimal position; updating the current position of each selected point according to its current position and the updated adjustment displacement; after the current position is updated for a set number of times, selecting the position corresponding to the optimal evaluation index from the current positions and global optimal position of all selected points as the next waypoint of the aerocraft.