141 results about "Flight duration" patented technology

The invention provides a gas ultrasonic transducer fast matching method, device and equipment and a storage medium, original measurement data such as flight time are obtained by deploying an ultrasonic transducer in a gas ultrasonic flowmeter in a gas conveying pipeline, and multi-dimensional data acquisition is carried out in combination with other sensor parameters. Wavelet noise reduction and dynamic time warping processing are carried out on collected signals, signal quality and time sequence consistency are improved, time domain, frequency domain, environment and statistical features are extracted, and multi-dimensional feature vectors are formed. Modeling is carried out through a time sequence feature branch and an environment feature branch, weighted fusion is carried out by adopting an attention mechanism, and the recognition capability of the model on key features is enhanced. A machine learning model is trained based on fusion features, a multi-objective loss function and a data enhancement strategy are adopted, the prediction precision and generalization ability of the model are improved, and a compensation value is output to calibrate the original traffic in real time. According to the method, the accuracy and stability of gas flow measurement in a complex environment are effectively improved, and the method has a good engineering application prospect.

The invention discloses a self-adaptive ultrasonic measurement method and system based on multi-channel cooperation, and relates to the technical field of ultrasonic measurement. The method comprises the following steps: collecting original flight time signals of each channel; meanwhile, environment data are collected in real time; original flight time signals are processed, effective signal arrival pre-flight time is extracted, and a fusion data set is constructed; constructing a two-dimensional sound channel spectrogram based on the multi-sound channel time sequence of the pre-flight time, and performing feature extraction based on a lightweight convolutional neural network to generate an abnormal confidence vector; analyzing the sound channel state based on the abnormal confidence vector; constructing a physical information neural network, and analyzing the corrected sound velocity value of each sound channel and the two-dimensional sound velocity field distribution on the section of the whole pipeline; training an online sequence extreme learning machine model in combination with historical measurement data; and based on the final fusion weight of each sound channel and the corresponding sound channel flow velocity, carrying out weighted fusion to generate a flow velocity optimal estimation value. And the measurement precision and robustness are improved.

The invention discloses an intelligent flight route planning method and system for a low-altitude logistics aircraft, and the method comprises the steps: obtaining the three-dimensional space map data of the current position of the aircraft, including the coordinate information of a building and a telegraph pole, and the boundary range of a no-fly zone; acquiring wind speed, wind direction and rainfall data of the current area from a meteorological data source, and calculating meteorological impact factors by combining aircraft performance parameters; dynamically adjusting the candidate flight routes according to the maneuvering characteristic parameters of the aircraft, and calculating the flight time, the energy consumption cost and the safety risk score of each route; meteorological changes in the flight process are monitored in real time, and if the meteorological conditions exceed a preset threshold value, the meteorological data are obtained again, and the meteorological influence factors are updated; and carrying out local optimization adjustment on the current flight route according to the updated meteorological influence factor, generating a new flight route segment and replacing the original segment.

The invention provides a flight time determination method of an ultrasonic flowmeter and related equipment, and relates to the field of ultrasonic measurement. The method comprises the following steps: acquiring uplink and downlink echo signals of the ultrasonic flowmeter, and determining uplink and downlink envelope arrays corresponding to the uplink and downlink echo signals; determining uplink and downlink characteristic waves and respective zero crossing point time of the uplink and downlink characteristic waves based on the uplink and downlink envelope arrays; according to a preset interval length and the respective zero crossing point time of the uplink characteristic wave and the downlink characteristic wave, a first envelope interval array and a second envelope interval array as well as a front offset envelope interval array and a rear offset envelope interval array are intercepted from the uplink envelope array and the downlink envelope array respectively; envelope difference arrays between the first envelope interval array and the second envelope interval array, between the first envelope interval array and the front offset envelope interval array and between the first envelope interval array and the rear offset envelope interval array are calculated, and the flight time of the ultrasonic flowmeter is determined according to the envelope difference arrays.

The invention discloses an elastomer layer carbon fiber composite material damage positioning method based on elliptic probability fusion, which comprises the following steps: taking different sensors as excitation sources, and collecting Lamb wave signals of a plurality of sensing paths; performing continuous wavelet transform by using a complex Morlet wavelet, and extracting actually measured flight time; introducing a layered wave velocity correction model to optimize an elliptical orbit method, and calculating theoretical flight time and damage probability; introducing a dynamic short-axis optimization model to optimize a probability weighting method, and calculating a damage probability; generating prior distribution by using results calculated by an elliptical orbit method and a probability weighting method; constructing a likelihood function based on the difference between the actually measured flight time and the theoretical flight time; the posterior distribution of the damage position is obtained through the Bayesian theorem in combination with the prior distribution and the likelihood function; sampling the posterior distribution by using an adaptive MCMC algorithm, and generating a probability cloud picture of the damage position; and outputting a final imaging result of the damage position, and positioning the damage position.

An illustrative sensor controller includes: a transmitter, a receiver, a time-of-flight circuit, and a phase shift circuit. The transmitter is configured to provide a drive signal to an ultrasonic sending transducer to generate an acoustic burst. The receiver is configured to receive a response signal from an ultrasonic receiving transducer. The time-of-flight circuit is configured to detect an arrival of the acoustic burst in the response signal and to measure a first time of flight associated with that arrival. The phase shift circuit is configured to measure a phase shift of the acoustic burst in the response signal and to determine a second time of flight corresponding to the phase shift.

The invention discloses a collaborative planning method for multi-unmanned aerial vehicle dynamic target positioning, and belongs to the field of unmanned aerial vehicle trajectory planning and visual perception, and the method comprises the steps: obtaining the position information of each unmanned aerial vehicle and a dynamic target in real time; modeling a multi-unmanned aerial vehicle system into a pseudo-rigid body structure, taking the geometric center of the structure as a path search node, and performing multi-unmanned aerial vehicle cooperative path search on the basis of the position information under the condition of meeting obstacle avoidance constraint and topological consistency constraint to obtain an initial trajectory of each unmanned aerial vehicle; multi-unmanned aerial vehicle combined continuous time-space trajectory optimization is carried out on the initial trajectory, the optimization target is to minimize control cost and flight time cost, and dynamic feasibility constraint, environment obstacle avoidance constraint, cluster mutual avoidance constraint and public view field constraint are met. By introducing the topological consistency constraint and the public view field constraint, mutual visibility among multiple machines is effectively maintained in a complex obstacle environment, it is guaranteed that a public view field area is not shielded, and the robustness of a dynamic target observation system is improved.

The invention discloses an ultrasonic guided wave damage ellipse imaging positioning method and equipment for a layer decreasing composite material laminated plate. The method comprises the following steps: S1, acquiring thickness change direction information of the laminated plate and position coordinates of an excitation transducer and a receiving transducer; s2, according to the material characteristic parameters, simulating and calculating the propagation time of ultrasonic guided waves transmitted from an excitation transducer to any point to generate a first theoretical propagation time map, and simulating and calculating the propagation time of the ultrasonic guided waves transmitted from any point to a receiving transducer to generate a second theoretical propagation time map to generate a second theoretical propagation time map; coupling influence of thickness change and material anisotropy on guided wave propagation is considered in the simulation process; s3, transmitting an ultrasonic guided wave signal, and extracting the actual flight time of a damaged wave packet; s4, calculating theoretical total propagation time, and determining a candidate area where damage exists; and S5, on the basis of repeated operation of the multiple groups of transducer pairs, taking a plurality of candidate region intersections to determine a final damage position. The objective of the invention is to solve the positioning error problem caused by the structural characteristics of a laminated plate in a traditional algorithm, and to realize more accurate damage detection and positioning.

A vertical takeoff and landing (VTOL) aircraft includes a maximum takeoff weight (MTOW) of about 1700-kg, a cruising speed of about 80-knots equivalent airspeed (EAS) to about 100-knots EAS, a nominal range of about 300-km, a nominal flight time of about 4-hours, and at least one pair of rotors configured to provide vertical thrust. Each rotor of the at least one pair includes an about 2-meter propeller diameter, a disk loading of about 67-kg / m2 to about 110-kg / m2, and an operating speed of about 1800 rotations-per-minute (RPM) to about 2700-RPM.

A method of in situ measurement of an acoustoelastic constant (L) of a railway rail, using an ultrasonic wedge sensor to measure a stress-free (unloaded) time-of-flight (t0) in the vertical direction of the rail. Next, a vertical load of known load value is applied to the rail. While the vertical load is applied, the ultrasonic wedge sensor is used to measure a stressed time-of-flight value. The difference between the stress-free and the stressed time-of-flight is calculated to obtain a time-of-flight difference value (Δt). Based on the load value, the stress-free time-of-flight value, and the time-of-flight difference value, the acoustoelastic constant, L, may be calculated. The wedge sensor may be further used to measure the (stressed) horizontal time of flight, and a time-of-flight difference value in the horizontal direction may be used to measure longitudinal stress.

Embodiments of the present invention provide a method for measuring the time-of-flight of a low-signal-to-noise ratio ultrasonic echo signal, relating to the field of measurement technology. The method comprises the steps of acquiring an echo signal; performing noise reduction and reconstruction on the acquired echo signal using an empirical wavelet transform to obtain a reconstructed echo signal; obtaining a preset reference echo peak value and a reconstructed echo peak value, and calculating the echo characteristic peak of the echo signal using a preset characteristic peak location algorithm; obtaining echo characteristic points of the echo; and measuring the echo time-of-flight based on the obtained echo characteristic points according to a preset measurement algorithm. This method can achieve higher-precision time-of-flight measurements of ultrasonic echo signals using a simpler calculation method.

The invention provides an earth-moon transfer orbit iterative calculation method based on earth-moon relative motion, which comprises the following steps: firstly, calculating an ideal earth-moon transfer orbit number according to the deviation between the current flight time and the theoretical time, and taking the ideal earth-moon transfer orbit number as an iterative guidance target orbit; and then, by utilizing the characteristic that the shutdown time of the rocket in the flight section can be predicted in the iterative guidance calculation process, the influence of the flight time deviation on the earth-moon transfer orbit is compensated to the number of target orbits in real time, so that correction of a guidance program angle instruction is realized, and the rocket is controlled to fly towards a more ideal earth-moon transfer orbit all the time.

This invention discloses an AI-based automatic positioning and navigation system for unmanned aerial vehicles (UAVs), comprising: a UAV body that obtains the starting coordinates through a navigation module by manually inputting the destination coordinates and the planned flight duration t, and then flies from the starting coordinates to the destination coordinates at a flight speed V1 and a flight altitude H1, automatically completing the flight mission and automatically determining the return-to-home status; and a monitoring unit that acquires the initial battery level Q of the UAV body, transmits the initial battery level to the coordinate unit, and monitors the output power of the battery in real time during flight. When abnormal output power occurs during flight, a feedback signal is generated and transmitted to the correction unit. This invention relates to the field of UAV technology and solves the problem that existing UAV automatic positioning and navigation systems do not consider the UAV's battery life, which can easily lead to the UAV being unable to return to home or even crashing during flight.

The invention relates to an unmanned aerial vehicle appearance inspection method and system based on a large model and intelligent glasses, and relates to the field of unmanned aerial vehicle detection, and the method comprises the steps: obtaining the model and the historical abnormal position of an unmanned aerial vehicle and the task information of a to-be-executed task, and determining the inspection process of the unmanned aerial vehicle according to the model and the historical abnormal position, the task information comprises a flight distance, a flight duration and a wind speed, controlling the intelligent glasses to output an inspection process, so that a person acts according to the inspection process and collects a plurality of appearance images of the unmanned aerial vehicle, and inputting the plurality of appearance images into a plurality of trained anomaly detection models for anomaly detection. And obtaining a detection result of each anomaly detection model, and judging whether the unmanned aerial vehicle is allowed to release or not according to the multiple detection results and the task information. The appearance state of the unmanned aerial vehicle can be quickly determined when the unmanned aerial vehicle needs to execute the emergency task, and whether release is allowed or not is accurately judged.

Provided in the present application are a flight duration measurement method and a related device thereof, which are applied to a field programmable gate array, the field programmable gate array being provided with at least one carry chain. The measurement method comprises: for each of a plurality of event signals, acquiring a first transmission duration of the event signal on a carry chain within a time period between an edge instant of the event signal and an edge instant of an adjacent clock signal, the first transmission duration representing an edge delay of the event signal, and the plurality of event signals comprising a transmission signal and a reception signal; acquiring a second transmission duration of each clock signal transmitted in the carry chain, the second transmission duration representing a jitter duration of the clock signal; and compensating the edge delays and the jitter durations of the plurality of event signals to an initial flight duration, so as to obtain a first flight duration, wherein the initial flight duration is obtained on the basis of edge instants of the transmission signal and the reception signal.

The invention relates to the technical field of unmanned aerial vehicle flight plan dynamic management scheme design, in particular to a multi-type unmanned aerial vehicle town multi-scene flight plan dynamic management method and system. The method comprises the following steps: receiving and analyzing a multi-scene task request to obtain an emergency degree, a load demand, a flight duration and an execution area attribute of the multi-scene task request; on the basis of task attributes, the tasks are divided into execution waves of different priorities according to the emergency degree priority and region cooperation principle; acquiring the load state, the remaining flight duration and the position information of the unmanned aerial vehicle in real time; for each wave, dynamically matching the unmanned aerial vehicles which are compatible in load, sufficient in endurance and adjacent in position; executing tasks according to a wave priority sequence, and monitoring the state of the unmanned aerial vehicle in real time; and when triggering conditions such as insufficient endurance or a new high-emergency task occur, the execution plan is dynamically adjusted. According to the invention, through wave management and dynamic closed-loop control, efficient and reliable adaptation of multi-type unmanned aerial vehicle resources and complex task requirements of cities and towns is realized.

The invention discloses an unmanned aerial vehicle path planning system based on dynamic environment updating, which relates to the technical field of unmanned aerial vehicle planning and comprises a path planning module, a real-time environment acquisition subsystem, a path updating subsystem and an unmanned aerial vehicle control module. A user sets initial relevant parameters of a flight route of the unmanned aerial vehicle through the path planning module, and meanwhile, environment data in the flight process are collected and captured in real time through the implementation environment collection subsystem, and the environment data are processed and analyzed; and the path updating subsystem re-plans and re-designs a flight path of the unmanned aerial vehicle according to the processed environment data content, and transmits the flight path to a control module of the unmanned aerial vehicle through a wireless signal to carry out corresponding flight control operation on the unmanned aerial vehicle. According to the unmanned aerial vehicle path planning system, the flight path of the unmanned aerial vehicle is synchronously adjusted according to the environment change condition updated in real time, more efficient unmanned aerial vehicle flight operation is achieved, and the flight duration of the unmanned aerial vehicle is shortened.

The time-of-flight mass spectrometer provided by the embodiment of the application comprises a flight tube, a detector and an ion focusing assembly, the detector and the ion focusing assembly are arranged in the flight tube, the ion focusing assembly is arranged at the front end of the detector, the flight tube is used for flight control of ions, the ion focusing assembly is used for focusing of the ions after flight, and the detector is used for detection of the focused ions. Through focusing of the ions after flight, the number of ions detected by the detector can be improved, and the sensitivity of the time-of-flight mass spectrometer is higher.

The embodiment of the invention provides a bolt residual axial force determination method and device, electronic equipment, a medium and a product, and the method comprises the steps that a to-be-tested bolt in a first installation state is tested, the flight time difference variable quantity caused by axial force attenuation is obtained, and the first installation state represents that the bolt is in a yield section; determining an axial force attenuation based on an axial force attenuation parameter of the to-be-tested bolt in a second installation state and a flight time difference variation, the second installation state representing that the bolt is in an elastic section; and determining the residual axial force of the to-be-tested bolt according to the axial force attenuation. According to the method provided by the embodiment of the invention, the residual axial force can be calculated more accurately based on the axial force attenuation parameter of the bolt. And according to the scheme provided by the invention, bolts do not need to be disassembled in the test process, so that the continuity and completeness of the test are ensured.

The invention relates to an ultrasonic wave flight time measuring method and device, electronic equipment and a readable medium, and the method comprises the steps: applying a driving signal to a first transducer, enabling the first transducer to emit ultrasonic waves, and starting a timer to collect a transmitted waveform sequence; calculating the minimum flight time as a coarse value based on the distance between the transducers and the resultant velocity of the sound velocity and the wind speed; after the time is over, collecting a receiving waveform sequence of which the count value and the amplitude are within a preset range; transmitting and receiving waveforms are analyzed through waveform matching, a time offset value is obtained, and a coarse value is corrected to obtain first absolute flight time; switching a transmitting-receiving transducer, and similarly obtaining second absolute flight time; and matching the two received waveforms, calculating the offset time for correcting the difference between the two minimum flight times, and finally obtaining the high-precision relative flight time. The problem that the measurement precision and the operation efficiency cannot be considered when the ultrasonic flight time is measured is solved.

The invention relates to a flight time difference calculation method of an ultrasonic flowmeter and related equipment, and the method comprises the steps: respectively dividing an uplink echo signal and a downlink echo signal to obtain a plurality of continuous local waves, extracting a characteristic value representing the amplitude range of the local wave from each local wave, and calculating the flight time difference of the ultrasonic flowmeter according to the characteristic value; sorting the feature values according to the sampling time of the local waves to obtain an uplink feature value sequence and a downlink feature value sequence; in a preset integer local wave shift number interval, for each preset shift number, performing translation alignment on the downlink characteristic value sequence relative to the uplink characteristic value sequence according to the preset shift number to obtain a downlink characteristic value sub-sequence; and calculating a matching difference degree between each downlink eigenvalue sub-sequence and the uplink eigenvalue sequence, determining a target local wave shift number according to the matching difference degree, and determining a flight time difference according to the target local wave shift number. According to the method, the calculation accuracy of the flight time difference is remarkably improved, and the measurement accuracy of the fluid flow is ensured.

The application discloses a speed-restricted separation method of a solid rocket engine-boosted vehicle, which comprises the following steps: S1, determining a first maximum speed threshold Vmax1, a second maximum speed threshold Vmax2 and a latest separation time Tmax; S2, comparing a full-missile flight speed Vt0 at the end of engine operation with the first maximum speed threshold Vmax1, and separating the vehicle in time at the end of engine operation when Vt0Vmax1, entering step S3; S3, delaying the separation of the vehicle after the end of engine operation; the specific method of delaying the separation is as follows: if the full-missile flight time is less than Tmax, comparing a full-missile flight speed Vt at the current time with Vmax2, separating the vehicle when VtVmax2, and continuing the full-missile flight when Vt≥Vmax2; if the full-missile flight time is greater than or equal to Tmax, separating the vehicle. The application can judge the separation time according to the real-time flight speed, provide a suitable speed after the separation of the main stage, and ensure the flight control requirements and speed requirements of the main stage after the separation.

The utility model belongs to the technical field of unmanned aerial vehicles, and particularly relates to an unmanned aerial vehicle fuselage which comprises a fuselage body, the fuselage body comprises a first frame and a second frame, the first frame and the second frame are both triangular frames, and the first frame and the second frame are fixedly connected and arranged in the axial direction of the fuselage body. The end corner of the first frame and the end corner of the second frame are arranged in a staggered mode in the direction perpendicular to the axis of the fuselage. According to the structure, the first frame and the second frame are triangular, due to the stability of the triangles, the fuselage of the unmanned aerial vehicle has stability, the first frame and the second frame are arranged in a staggered mode, and six small triangular structures are formed at the six corners, so that the fuselage is more stable and firmer; moreover, parts are convenient to replace, the fuselage is simple in structure, easy to process and mount and light in weight, and the flight time of the unmanned aerial vehicle is prolonged.

The invention discloses an intelligent dispatching method for flight departure / departure moments. The method comprises the following steps: establishing a moment distribution calculation model; establishing a flight duration calculation model; judging whether the takeoff moment and the landing moment reported by the airline company meet the flight duration requirement specified by the civil aviation bureau; whether the take-off moment or the landing moment reported by the airline company has idle moments at the take-off airport or the landing airport or not is judged; calculating a suggested moment when the landing moment declared by the airline company cannot be allocated; calculating a suggested moment when the takeoff moment declared by the airline company cannot be allocated; calculating suggested moments when the takeoff moment and the landing moment declared by the airline company cannot be allocated; an airline company calculation result is fed back; and airline company result confirmation. According to the method, the availability can be analyzed by using the preset model when the airline declares the start / fall moment of the flight; and if no time slot exists at the original moment, the adjacent moments conforming to airport flow tolerance and civil aviation duration are automatically recommended according to an airline acceptance range, so that the airline can conveniently reprogram a flight plan.

The invention discloses a two-way rocket launching window searching method, system and device and a medium, and the method comprises the steps: rapidly calculating two nearest launching windows of an ascending orbit and a descending orbit of a rocket according to the attributes of a central body, target orbit plane parameters, the geographic coordinates of launching points and the flight duration of the rocket; according to the method, the problem is converted into numerical calculation based on space geometry, the crossing moment is directly solved by using the geometrical relationship between the normal vector of the orbital plane and the inertial position vector of the launching point location and adopting efficient numerical methods such as dichotomy and the like, and complex dynamic iteration is avoided. According to the method, the calculated amount is greatly reduced, rapid searching of the launching window is achieved, the method is suitable for an interstellar detection task scene needing rapid response or multiple times of calculation, and the real-time performance of task planning is remarkably improved.

To reduce variation of a measurement result by aligning a mass resolution of a plurality of devices.SOLUTION: In an embodiment of a TOFMS according to the present invention, the TOFMS includes a measurement part (1) containing: each flight magnetic field formation part that forms a magnetic field for flying an ion into a flight space (153, 154, and 155); and each ion acceleration part (151 and 152) that accelerates the ion as a measurement object and feeds it into the flight space. The TOFMS comprises: a control part (3) that repeatedly executes a measurement to a predetermined sample while changing a voltage applied to an electrode contained in the measurement part, and operates the measurement part so as to calculates a mass resolution on the basis of the measurement result in each measurement; an approximate calculation part (3) that calculates an approximate for approximating a relation of them on the basis of data of a plurality of pairs of an application voltage to the electrode and a resolution corresponded to them, obtained under a control by the control part; and a voltage determination part (3) that calculates a voltage value corresponded to a target value of the mass resolution by using the approximate, and determines the voltage value as an application voltage to the electrode in the device.SELECTED DRAWING: Figure 1

The invention discloses a water outlet control method, system and equipment, and relates to the technical field of water outlet control, and the method comprises the steps: after a water supply device is started, signals are transmitted and received alternately based on two probe cores, and a first echo signal and a second echo signal of a container upper edge and a container liquid level on a container tray are obtained in real time; performing data intensity judgment based on the first echo signal and the second echo signal, and performing screening to obtain an effective echo signal; performing preprocessing based on the effective echo signal to obtain an upper edge envelope signal and a liquid surface envelope signal; acquiring corresponding first flight time and second flight time based on the upper edge envelope signal and the liquid surface envelope signal; obtaining a height difference between the upper edge of the container and the liquid level of the container based on the first flight time and the second flight time; starting and stopping of the water supply device are controlled based on the height difference; acquiring pressure data of the container tray in real time, and controlling start and stop of the water supply device based on the pressure data. Accurate recognition of the container and the water adding state is achieved, and the water outlet control precision is improved.

A control system 70 includes: a VTOL rotor 20 and a cruise rotor 29 configured to generate a thrust; a power unit that has a power generation device 40a configured to generate power and supply the power to the rotors, and a battery 32 configured to store power which is supplied from the power generation device, and supply stored power to the rotors; and a control unit 91 configured to calculate a charging time of the battery based on a required amount of power storage that should be stored in the battery when the aircraft flies in a predetermined flight condition, and a state of the battery, and determine a charge start time of the battery based on the charging time and a flight time it takes to reach the predetermined flight condition. With this, it is possible to suppress a deterioration.

Method, system, and user terminal are disclosed for splicing a flight route splicing m. Various embodiments may includes: obtaining a first flight route and a second flight route of an unmanned aerial vehicle; obtaining a first estimated flight duration of the UAV required to complete the first flight route and the second flight route; obtaining the preset duration of the unmanned aerial vehicle; splicing the first flight route and the second flight route when the preset duration is greater than the first estimated flight duration. it improves the task execution efficiency of the unmanned aerial vehicle and saving the unmanned aerial vehicle resources and time, and further providing richer choices for users and providing more space for customized flight route planning for users.

The invention provides a Doppler effect elimination and fusion positioning method for a high-speed train, and the method comprises the steps: deducing a mathematical expression of a distance measurement error caused by a Doppler effect based on a bidirectional time of flight (ToF) method; secondly, using UWB / IMU time sequence prior to eliminate distance measurement error deviation, and analyzing residual error variance; and finally, constructing a self-adaptive UWB / IMU fusion positioning framework, deducing a UWB measurement equation random item closed expression, and realizing Doppler effect elimination and fusion model parameter self-adaptive adjustment. According to the method, the precision of UWB / IMU fusion positioning is remarkably improved, and the influence of the Doppler effect on the bidirectional ToF ranging and fusion positioning model is overcome.