Method for calculating vertical speed of aircraft, aircraft and computer-readable storage medium

Abstract

The embodiment of the application discloses an aircraft vertical speed calculation method, an aircraft and a computer readable storage medium. The method comprises the following steps: obtaining height data by performing validity preprocessing on a measured height obtained by a height measuring instrument; calculating a height measuring instrument vertical speed based on the height data; obtaining a comprehensive vertical speed and a current flight phase, determining weight coefficients of the comprehensive vertical speed and the height measuring instrument vertical speed based on the current flight phase; and calculating a final vertical speed by performing weighted fusion on the comprehensive vertical speed and the height measuring instrument vertical speed according to the weight coefficients and outputting the final vertical speed. Therefore, the application can improve the calculation accuracy of the vertical speed of the aircraft.

Description

Technical Field

[0001] This application belongs to the field of aircraft control technology, and in particular relates to a method for calculating the vertical velocity of an aircraft, an aircraft, and a computer-readable storage medium. Background Technology

[0002] With the booming development of the low-altitude economy, new types of aircraft such as drones and electric vertical takeoff and landing (eVTOL) aircraft are increasingly widely used in logistics, urban transportation, and other fields. Vertical velocity, as a key parameter for measuring the motion state of an aircraft, directly affects flight safety and control stability. However, existing designs mainly rely on GPS azimuth velocity, atmospheric combined vertical velocity, and inertial calculations. In urban low-altitude environments, near takeoff and landing platforms, near-ground low-speed environments, and complex reflection environments, vertical velocity information is easily affected by factors such as satellite obstruction, multipath effects, air pressure disturbances, and inertial drift, leading to short-term fluctuations, response lags, or decreased reliability. It is often difficult to guarantee the real-time performance and accuracy of vertical velocity calculations, which can easily lead to control deviations or even safety accidents. Therefore, a high-precision vertical velocity calculation method is urgently needed to meet the high-reliability navigation requirements of low-altitude aircraft.

[0003] The preceding description is intended to provide general background information and does not necessarily constitute prior art. Summary of the Invention

[0004] The purpose of this application is to provide a method for calculating the vertical velocity of an aircraft, an aircraft, and a computer-readable storage medium, which can improve the accuracy of the vertical velocity calculation of an aircraft.

[0005] To achieve the above objectives: In a first aspect, embodiments of this application provide a method for calculating the vertical velocity of an aircraft. The method includes the following steps: performing validity preprocessing on the measured altitude obtained by an altimeter to obtain altitude data; calculating the vertical velocity of the altimeter based on the altitude data; obtaining the composite vertical velocity and the current flight stage, and determining the weighting coefficients of the composite vertical velocity and the altimeter vertical velocity based on the current flight stage; and performing weighted fusion of the composite vertical velocity and the altimeter vertical velocity according to the weighting coefficients to calculate and output the final vertical velocity.

[0006] In an optional embodiment of this application, after performing validity preprocessing on the measured altitude obtained by the altimeter, altitude data is obtained, including: determining validity screening conditions based on the current flight phase and current attitude state, the validity screening conditions including valid measurement range, rate of change threshold and abnormal jump tolerance; performing real-time filtering and anomaly removal on the measured altitude according to the validity screening conditions; and using the processed measured altitude as altitude data.

[0007] In an optional embodiment of this application, the vertical speed of the height measuring instrument is calculated based on the height data, including: dividing the height data into multiple segments of height sub-data according to a preset time window; calculating the height representative value of each segment of height sub-data, wherein the height representative value is any one of the mean, median or weighted average of the height sub-data; and obtaining the vertical speed of the height measuring instrument by differentiating the height representative value with the preset time window.

[0008] In an optional embodiment of this application, the calculation of the vertical velocity of the altimeter based on altitude data includes: determining the current flight phase; when the current flight phase is the vertical takeoff phase, dividing the altitude data into multiple segments of altitude sub-data within a first time window and then calculating the vertical velocity of the altimeter; the length of the first time window is shorter than the length of the time window corresponding to other flight phases; when the current flight phase is the hovering phase, performing smoothing processing on the altitude data; calculating the vertical velocity of the altimeter using the processed altitude data; when the current flight phase is the near-ground descent phase, removing data points in the altitude data that do not meet the descent conditions; calculating the vertical velocity of the altimeter using the removed altitude data; when the current flight phase is the vertical landing phase, removing data points in the altitude data that have abnormal jumps; calculating the vertical velocity of the altimeter using the removed altitude data.

[0009] In an optional embodiment of this application, obtaining the composite vertical speed and the current flight phase, and determining the weighting coefficients of the composite vertical speed and the altimeter vertical speed based on the current flight phase, includes: calculating the reliability of the composite vertical speed and the altimeter vertical speed based on the current flight phase; and calculating the weighting coefficients of the composite vertical speed and the altimeter vertical speed respectively based on the reliability of the composite vertical speed and the altimeter vertical speed.

[0010] In an optional embodiment of this application, the composite vertical velocity includes at least one of the following: axial velocity, atmospheric combined vertical velocity, and inertial calculated vertical velocity. Calculating the reliability of the composite vertical velocity and the altimeter vertical velocity based on the current flight phase includes: acquiring reliability evaluation factors for both the composite vertical velocity and the altimeter vertical velocity, whereby the reliability evaluation factors include at least one of altitude range, sensor operating status, data continuity, data change rate, attitude change, and environmental influence; calculating the data consistency rate among the axial velocity, atmospheric combined vertical velocity, inertial calculated vertical velocity, and altimeter vertical velocity based on the reliability evaluation factors; removing data sources with a data consistency rate lower than a preset threshold, and using the remaining data consistency rate as the reliability of the corresponding vertical velocity.

[0011] In an optional embodiment of this application, the combined vertical velocity and the altimeter vertical velocity are weighted and fused according to weighting coefficients, including: determining the current flight phase; when the current flight phase is any of the vertical takeoff phase, hovering phase, and / or vertical landing phase, increasing the weighting coefficient of the altimeter vertical velocity and using it to solve for the final vertical velocity; when the current flight phase is the end of the departure phase and / or the beginning of the approach phase, decreasing the weighting coefficient of the altimeter vertical velocity and using it to solve for the final vertical velocity; when the current flight phase is the approach phase, dynamically correcting the weighting coefficient of the altimeter vertical velocity based on altitude data, and solving for the final vertical velocity based on the corrected weighting coefficient.

[0012] In an optional embodiment of this application, the weighted fusion of the overall vertical velocity and the vertical velocity of the altimeter is performed according to a weighting coefficient, including: when the altitude data meets the preset low-altitude conditions, the weighting coefficient of the vertical velocity of the altimeter is dynamically increased based on the altitude data, and the final vertical velocity is calculated based on the corrected weighting coefficient; when the altitude data meets the preset high-altitude conditions, the weighting coefficient of the vertical velocity of the altimeter is dynamically decreased based on the altitude data, and the final vertical velocity is calculated based on the corrected weighting coefficient.

[0013] Secondly, embodiments of this application provide an aircraft, including: a processor and a memory storing a computer program, wherein when the processor runs the computer program, the steps of the above-described method are implemented.

[0014] Thirdly, embodiments of this application provide a computer-readable storage medium storing a computer program that, when executed by a processor, implements the steps of the above-described method.

[0015] The embodiments of this application have the following beneficial effects: The vertical velocity calculation method for an aircraft provided in this application includes the following steps: performing validity preprocessing on the measured altitude obtained by an altimeter to obtain altitude data; calculating the vertical velocity of the altimeter based on the altitude data; obtaining the composite vertical velocity and the current flight phase, and determining the weighting coefficients of the composite vertical velocity and the altimeter vertical velocity based on the current flight phase; weighted fusing the composite vertical velocity and the altimeter vertical velocity according to the weighting coefficients to calculate and output the final vertical velocity. Therefore, this application no longer simply uses the altitude measurement data directly for display, but uses the altimeter as a highly reliable near-ground altitude source for the vertical takeoff and landing (VTOL) phase. Through specialized vertical velocity calculation and fusion logic, it is transformed into vertical velocity information that can be used for navigation and flight control. The fusion weights of the multi-source vertical velocities are dynamically adjusted in different flight phases, transforming altitude change information into stable measured vertical velocity, and dynamically weighted fusing it with the composite vertical velocity from multiple sources, thereby forming a continuous, reliable, and smooth combined vertical velocity output, improving the near-ground vertical control accuracy, descent rate control stability, and VTOL safety of the aircraft.

[0016] The above description is merely an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it according to the contents of the specification, and to make the above and other objects, features and advantages of this application more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. It should be understood that the above general description and the following detailed description are merely exemplary and explanatory, and do not limit this application. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a flowchart illustrating a method for calculating the vertical velocity of an aircraft, provided as an embodiment.

[0019] Figure 2 This is a schematic diagram of the flight phase of an aircraft as provided in one embodiment.

[0020] Figure 3 This is a schematic block diagram of the structure of a computer device provided in one embodiment. Detailed Implementation

[0021] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. In the following description relating to the drawings, unless otherwise indicated, the same numerals in different drawings denote the same or similar elements.

[0022] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element. Furthermore, components, features, and elements with the same names in different embodiments of this application may have the same meaning or different meanings, the specific meaning of which must be determined by its interpretation in that specific embodiment or further in conjunction with the context of that specific embodiment.

[0023] It should be understood that although the terms first, second, third, etc., may be used herein to describe various information, such information should not be limited to these terms. These terms are used only to distinguish information of the same type from one another. For example, without departing from the scope of this document, first information may also be referred to as second information, and similarly, second information may also be referred to as first information. Depending on the context, the word "if," as used herein, can be interpreted as "when," "when," or "in response to determination." Furthermore, as used herein, the singular forms "a," "an," and "the" are intended to also include the plural forms unless the context indicates otherwise. It should be further understood that the terms "comprising," "including," indicate the presence of the stated feature, step, operation, element, component, item, kind, and / or group, but do not exclude the presence, occurrence, or addition of one or more other features, steps, operations, elements, components, items, kinds, and / or groups. The terms "or" and "and / or" as used herein are to be interpreted as inclusive, or mean any one or any combination thereof. Therefore, "A, B, or C" or "A, B, and / or C" means "any one of the following: A; B; C; A and B; A and C; B and C; A, B, and C". Exceptions to this definition will only occur if the combination of elements, functions, steps, or operations is inherently mutually exclusive in some way.

[0024] It should be understood that although the steps in the flowcharts of this application's embodiments are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some of the steps in the figures may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily completed at the same time, but can be executed at different times, and their execution order is not necessarily sequential, but can be performed alternately or in turn with other steps or at least a portion of the sub-steps or stages of other steps.

[0025] It should be noted that step designations such as S110 and S120 are used in this document for the purpose of more clearly and concisely describing the corresponding content, and do not constitute a substantial limitation on the order. In specific implementation, those skilled in the art may execute S120 first and then S110, etc., but these should all be within the protection scope of this application.

[0026] It should be understood that the specific embodiments described herein are merely illustrative of this application and are not intended to limit this application.

[0027] In the following description, the use of suffixes such as "module," "part," or "unit" to denote elements is solely for the purpose of illustrative purposes and has no specific meaning in itself. Therefore, "module," "part," or "unit" may be used interchangeably.

[0028] To facilitate understanding of this application, the following explanations are provided for the terms and technical objects that may be used in this application: eVTOL (electric vertical take-off and landing) aircraft: eVTOL aircraft are characterized by vertical take-off and landing, low-altitude operation, small-radius turning, and adaptability to complex urban environments. Compared with traditional fixed-wing aircraft, eVTOL relies more on vertical altitude, vertical speed, and descent rate control during take-off and landing, especially during take-off, hovering, near-ground descent, and pre-touchdown phases. The stability and accuracy of the vertical speed source directly affect the aircraft's attitude control, vertical trajectory maintenance, landing impact control, and passenger comfort.

[0029] Existing designs primarily rely on GPS vertical velocity, atmospheric combined vertical velocity, and inertial calculated vertical velocity. However, in urban low-altitude environments, near takeoff and landing platforms, near-ground low-speed environments, and complex reflection environments, these conditions are easily affected by factors such as satellite obstruction, multipath effects, air pressure disturbances, and inertial drift, leading to short-term fluctuations, response lags, or decreased reliability of the vertical velocity information. To overcome the shortcomings of existing technologies, this application proposes a method for calculating the vertical velocity of an aircraft. For a clear description of the method provided in this embodiment, please refer to... Figures 1-2 This includes steps S110 to S140.

[0030] Step S110: After performing validity preprocessing on the measured height obtained by the height measuring instrument, the height data is obtained.

[0031] In one embodiment, the method provided in this application is applied to an aircraft, which may be an unmanned aerial vehicle or an eVTOL aircraft. Existing eVTOL navigation methods typically rely on GPS / GNSS, inertial navigation, atmospheric data, and flight control integrated navigation information to provide altitude and vertical velocity. GPS / GNSS can provide three-dimensional position and azimuth velocity, but in scenarios such as low-altitude urban areas, dense buildings, and near take-off and landing platforms, (1) it is easily affected by obstruction, multipath effects, electromagnetic environment, and changes in satellite geometry; (2) atmospheric data can provide barometric altitude and barometric vertical velocity, but its near-ground phase is affected by barometric pressure disturbances, ground effects, low-speed airflow fields, and sensor lag, making it difficult to meet the fine control requirements for low altitude and high dynamic vertical velocity during the vertical take-off and landing phase on its own; (3) inertial data has good short-term continuity, but there is integral drift, requiring constraints from other altitude sources.

[0032] An altimeter can directly measure the altitude of an aircraft relative to the ground, landing platform, or target landing area, especially with high accuracy in the near-ground altitude range, making it suitable for altitude discrimination and descent rate control during eVTOL vertical takeoff and landing phases. Specifically, an altimeter can be a radio altimeter, laser rangefinder, or lidar—a sensor capable of acquiring distance information between the aircraft and the ground, landing platform, or target landing area. However, altimeters typically only output altitude information directly, not the high-quality vertical velocity that can be used for flight control laws. Directly performing point-by-point differential analysis on the altitude measurement data can easily amplify measurement noise and high-frequency jumps, generating vertical velocity spikes. Furthermore, altitude measurement data is affected by factors such as terrain below the aircraft, obstacles, personnel or vehicle passage, and reflections from platform edges, potentially resulting in short-term jumps or outliers, making it unusable as vertical velocity. Therefore, to achieve high-precision near-ground data from an altimeter, this application first performs validity preprocessing on the raw altitude data.

[0033] In one embodiment, after performing validity preprocessing on the measured altitude acquired by the altimeter, altitude data is obtained, including: determining validity screening conditions based on the current flight phase and current attitude state, the validity screening conditions including valid measurement range, rate of change threshold and abnormal jump tolerance; performing real-time filtering and anomaly removal on the measured altitude according to the validity screening conditions; and using the processed measured altitude as altitude data.

[0034] In one implementation, the initial data acquired by the altimeter is referred to as the measured altitude. The measured altitude may be affected by factors such as terrain below the aircraft, obstacles, the passage of personnel or vehicles, and reflections from platform edges. This can cause short-term jumps or outliers in the data, leading to distortion of the vertical velocity after direct differentiation. Therefore, the measured altitude needs to undergo validity preprocessing. Specifically, validity screening criteria can be determined based on the current flight phase and current attitude state. (Flight phase, refer to...) Figure 2 As shown, the flight path can be broadly divided into: Phase I (vertical takeoff), Phase II (departure), Phase III (cruise), Phase IV (approach), and Phase V (vertical landing), as well as a special hovering phase. The sensitivity and tolerance for altitude data vary across different phases, and flight attitudes also differ. For example, hovering and landing phases are extremely sensitive to sudden altitude changes, while the cruise phase, due to its high speed and altitude, has a relatively high tolerance for instantaneous altitude fluctuations. Therefore, different validity screening criteria need to be set according to different flight phases and attitudes.

[0035] Validity screening criteria can specifically include the effective measurement range, the rate of change threshold, and the tolerance for abnormal jumps. These threshold parameters can be dynamically adjusted based on the flight phase and attitude. For example, during the vertical takeoff phase, when the aircraft is at a low altitude and accelerating upwards, the effective measurement range can be set to 0 to 50 meters, the rate of change threshold should match the maximum climb acceleration, and the tolerance for abnormal jumps should be appropriately relaxed to filter ground clutter interference while retaining the true acceleration trend. During the hovering phase, the aircraft is relatively stationary, and the rate of change of altitude theoretically approaches zero. At this time, the rate of change threshold should be set to a minimum value, and any fluctuation exceeding this threshold should be considered noise or abnormal jumps. It is understood that the above values ​​are simple examples combining flight attitude and flight phase, and are not specific limitations on the scheme. In practical applications, they can be flexibly configured according to the aircraft performance and environmental characteristics, and this application does not impose specific restrictions on them.

[0036] By using validity screening criteria, outlier data points in the measured height that do not meet the criteria can be filtered and removed in real time, thereby ensuring the purity and reliability of subsequent height data. The processed measured heights are then used as the height data.

[0037] Step S120: Calculate the vertical speed of the height measuring instrument based on the height data.

[0038] In one embodiment, the aircraft calculates the rate of change of altitude relative to the ground, takeoff and landing platform, or target landing area based on the continuously output altitude measurement data from the altimeter, thus forming the altimeter's vertical velocity. To avoid directly amplifying measurement noise through point-by-point differential processing, this application employs a smooth differential algorithm to process the altitude measurement data.

[0039] In one embodiment, calculating the vertical speed of the altimeter based on altitude data includes: dividing the altitude data into multiple segments of altitude sub-data according to a preset time window; calculating the representative value of the altitude for each segment of altitude sub-data, wherein the representative value is any one of the mean, median, or weighted average of the altitude sub-data; and obtaining the vertical speed of the altimeter by differentiating the representative value of the altitude from the preset time window.

[0040] In one embodiment, for altitude data, this application divides continuous altitude data into several overlapping or non-overlapping subsequences according to a preset time window, each segment being referred to as altitude sub-data. Subsequently, for each segment of altitude sub-data, its statistical characteristic value is calculated as the "altitude representative value" for that time window. This representative value can be any one of the mean, median, or weighted average to effectively suppress random noise interference.

[0041] Subsequently, the vertical velocity of the altimeter is obtained by subtracting the representative height value from a preset time window. This subtraction process, which combines the ratio of the difference between the representative height values ​​of adjacent time windows to the time interval, calculates the rate of change of height at the current moment, which is taken as the vertical velocity of the altimeter. The calculation process can be referenced in the following formula.

[0042] (1) In the above formula, The vertical velocity of the height measuring instrument during the k-th time window; The index of the current time window; and The first The and the first The height of each time window represents a value; This represents the time interval between adjacent time windows.

[0043] In one embodiment, to further improve the stability of vertical velocity calculation, the method provided in this application can preprocess and filter the height data before calculating the vertical velocity of the altimeter to suppress single-point noise and short-term jumps; it can also perform secondary smoothing processing on the vertical velocity result after differential calculation to make the output vertical velocity of the altimeter more continuous and stable. For hovering or low-speed vertical movement phases, the system can set a small change suppression range to avoid frequent changes in vertical velocity due to measurement jitter. Through the above processing, the system can convert the height information output by the altimeter into vertical velocity information suitable for participation in vertical take-off and landing control and combined vertical velocity fusion.

[0044] In one embodiment, calculating the vertical velocity of an altimeter based on altitude data includes: determining the current flight phase; when the current flight phase is the vertical takeoff phase, dividing the altitude data into multiple segments of altitude sub-data within a first time window and then calculating the vertical velocity of the altimeter; the length of the first time window is shorter than the length of the time windows corresponding to other flight phases; when the current flight phase is the hovering phase, performing smoothing processing on the altitude data; calculating the vertical velocity of the altimeter using the processed altitude data; when the current flight phase is the near-ground descent phase, removing data points from the altitude data that do not meet the descent conditions; calculating the vertical velocity of the altimeter using the removed altitude data; when the current flight phase is the vertical landing phase, removing data points from the altitude data that exhibit abnormal jumps; and calculating the vertical velocity of the altimeter using the removed altitude data.

[0045] In one embodiment, the calculated vertical velocity from the altimeter can be further processed by performing dead zone processing, amplitude limiting processing, and outlier removal, taking into account the current flight phase. For example, for small fluctuations during hovering or low-speed vertical motion, the system suppresses these fluctuations to avoid misjudgments caused by measurement noise; for vertical velocity values ​​that significantly exceed the aircraft's motion capabilities, are inconsistent with the current flight phase, or are inconsistent with trends from other data sources, the system reduces their reliability or removes the outlier data.

[0046] Specifically, when the current flight phase is the vertical takeoff phase, the altitude data is divided into multiple segments within a first time window before calculating the altimeter's vertical velocity. This short window design aims to quickly respond to dynamic changes during the initial takeoff phase; therefore, the length of the first time window is shorter than the corresponding time windows for other flight phases. This allows for calculation of the altimeter's vertical velocity using more segments within the same time frame, effectively capturing instantaneous acceleration characteristics and improving the real-time performance and sensitivity of the vertical velocity calculation.

[0047] When the current flight phase is hovering, it's understood that the theoretical vertical velocity of the aircraft should approach zero. However, due to airflow disturbances and sensor noise, the actual measured value often exhibits irregular, minute oscillations. Therefore, a dead-zone suppression mechanism is introduced to smooth the altitude data. This smoothing process includes at least one of dead-zone processing, zeroing, or smoothing suppression. Specifically, vertical velocity fluctuations with amplitudes below a preset threshold are forcibly zeroed or smoothed to eliminate spurious vertical velocity fluctuations caused by measurement noise. The altimeter's vertical velocity is then calculated based on the processed altitude data. This setting aligns with the physical characteristics of hovering, preventing altitude measurement noise from being amplified differentially and forming spurious vertical velocity fluctuations.

[0048] When the current flight phase is the near-ground descent phase, the aircraft is susceptible to ground effect interference, leading to nonlinear distortion in altitude data. To balance vertical velocity responsiveness and descent rate stability, data points in the altitude data that do not meet the descent conditions can be removed. Specifically, not meeting the descent conditions can include a descent rate exceeding the maximum permissible descent rate; not meeting the descent trend, such as abnormal altitude increases or jumps; or a trend significantly inconsistent with other vertical velocity sources. Data points that do not meet any of these criteria are considered to have failed the descent conditions and are removed. It can be understood that altitude data continuously decreases during the near-ground descent phase, and this rate of decrease is related to the aircraft's descent speed. If the descent rate exceeds the aircraft's current descent speed or the maximum permissible descent rate, it can be considered to have exceeded the preset descent rate. Correspondingly, if the altitude data shows a non-monotonic decrease or an abnormal increase, it is determined that the descent trend condition is not met. This setting effectively filters out false altitude increase signals caused by ground effects, ensuring the smoothness and controllability of the altitude measurement speed calculated during the near-ground descent phase.

[0049] When the current flight phase is the vertical landing phase, data points exhibiting abnormal altitude jumps can be removed from the altitude data. These abnormal jumps can include, but are not limited to, short-term altitude jumps caused by platform edge reflections, obstacles below, or changes in ground reflection conditions. Such jumps often manifest as sudden and drastic fluctuations in altitude data, significantly deviating from the smooth deceleration characteristics of the landing process. Therefore, they can be removed from the altitude data to ensure the continuity and accuracy of the vertical velocity calculation at the moment of landing.

[0050] Step S130: Obtain the composite vertical speed and the current flight phase, and determine the weighting coefficients of the composite vertical speed and the altimeter vertical speed based on the current flight phase.

[0051] In one embodiment, a composite vertical velocity is obtained, which includes at least one of the following: axial velocity, atmospheric combined vertical velocity, and inertial calculated vertical velocity. All of the above data can be directly obtained based on the aircraft's settings. Furthermore, operational data of the aircraft can also be obtained, including but not limited to altitude range, sensor status, data continuity, and attitude changes, in addition to the current flight phase. The weights of each vertical velocity component can be dynamically adjusted using this data for weighted calculation.

[0052] In one embodiment, obtaining the composite vertical speed and the current flight phase, and determining the weighting coefficients of the composite vertical speed and the altimeter vertical speed based on the current flight phase, includes: calculating the reliability of the composite vertical speed and the altimeter vertical speed based on the current flight phase; and calculating the weighting coefficients of the composite vertical speed and the altimeter vertical speed respectively based on the reliability of the composite vertical speed and the altimeter vertical speed.

[0053] In one embodiment, the composite vertical velocity includes at least one of the following: azimuth velocity, atmospheric combined vertical velocity, and inertial calculated vertical velocity. Calculating the reliability of the composite vertical velocity and the altimeter vertical velocity based on the current flight phase includes: acquiring reliability evaluation factors for both the composite vertical velocity and the altimeter vertical velocity, whereby the reliability evaluation factors include at least one of altitude range, sensor operating status, data continuity, data change rate, attitude change, and environmental influence; calculating the data consistency rate among the azimuth velocity, atmospheric combined vertical velocity, inertial calculated vertical velocity, and altimeter vertical velocity based on the reliability evaluation factors; and removing data sources with a data consistency rate lower than a preset threshold, using the remaining data consistency rate as the reliability of the corresponding vertical velocity.

[0054] In one embodiment, in the multi-source vertical velocity reliability evaluation, the reliability of the vertical velocity from each data source needs to be evaluated separately to quantify the reliability of each data source under the current operating conditions. The reliability evaluation relies on reliability evaluation factors for each vertical velocity, specifically including at least one of altitude range, sensor operating status, data continuity, data change rate, attitude change, and environmental influence. By monitoring these factors in real time, the system can dynamically assess the consistency between data sources, thereby determining the reliability of a particular data source's vertical velocity and assigning differentiated weight coefficients to different flight phases. For example, when a vertical velocity source's data is continuous, changes reasonably, shows a consistent trend with other vertical velocity sources, and is applicable to the current flight phase, its reliability increases; when it experiences data loss, short-term jumps, exceeds its applicable range, is mismatched with the flight phase, or is significantly inconsistent with other vertical velocity sources, its reliability decreases, and it may temporarily exit fusion if necessary. Data sources with a data consistency rate lower than a preset threshold are removed, and the remaining data consistency rate is used as the reliability of the corresponding vertical velocity. The reliability of all remaining data sources is normalized to obtain the initial weight coefficients for each data source. This calculation method can refer to the following formula.

[0055] (2) (3) (4) (5) In the above formula, , , and These represent the weighting coefficients corresponding to the vertical velocity of the altimeter, the axial velocity, the atmospheric combined vertical velocity, and the inertial calculated vertical velocity, respectively, and the sum of the weighting coefficients is 1. , , and These represent the reliability scores for the vertical velocity of the altimeter, the axial velocity, the atmospheric combined vertical velocity, and the inertial calculated vertical velocity, respectively.

[0056] Step S140: The overall vertical velocity and the vertical velocity of the height measuring instrument are weighted and fused according to the weighting coefficient to calculate the final vertical velocity and output it.

[0057] In one embodiment, the altimeter vertical velocity, GPS azimuth velocity, atmospheric combined vertical velocity, and inertial calculated vertical velocity are dynamically weighted and fused according to the reliability of each vertical velocity source and the current flight phase to generate a combined vertical velocity. Overall, the final vertical velocity can be calculated using the following formula.

[0058] (6) In the above formula, This is the final vertical velocity; The vertical speed of the height measuring instrument; For the speed of the sky, For atmospheric combination vertical velocity, For inertial calculation of vertical velocity, all three are included in the comprehensive vertical velocity and can be obtained directly.

[0059] In one embodiment, the combined vertical velocity and the altimeter vertical velocity are weighted and fused according to weighting coefficients, including: determining the current flight phase; when the current flight phase is any of the vertical takeoff phase, hovering phase, and / or vertical landing phase, increasing the weighting coefficient of the altimeter vertical velocity and using it to solve for the final vertical velocity; when the current flight phase is any of the departure phase and / or cruise phase, decreasing the weighting coefficient of the altimeter vertical velocity and using it to solve for the final vertical velocity; when the current flight phase is the approach phase, dynamically correcting the weighting coefficient of the altimeter vertical velocity based on altitude data, and solving for the final vertical velocity based on the corrected weighting coefficient.

[0060] In one embodiment, during the calculation process, due to different flight stages, when the aircraft attitude changes significantly, or when factors such as the terrain below, obstacles, platform edges, and reflection conditions may affect the altitude measurement data, the weighting coefficient of the vertical velocity of the altimeter can be dynamically adjusted according to the different flight stages.

[0061] When the current flight phase is any of the vertical takeoff, hovering, and / or vertical landing phases, the altimeter typically provides a high-precision rate of relative altitude change. In this case, the altimeter's weighting coefficient can be further adjusted to increase its weighting coefficient, fully utilizing its high precision advantage in low-altitude, low-speed scenarios. Increasing the altimeter's weighting coefficient requires adjusting the weighting coefficients of the other vertical velocity sources to ensure the sum of all weights remains normalized. Based on the adjusted weighting coefficients, the contribution values ​​of each vertical velocity source are recalculated, resulting in a more accurate final vertical velocity.

[0062] When the current flight phase is at the end of the departure phase and / or the beginning of the approach phase, the altitude data measured by the altimeter is often subject to significant ground interference due to the aircraft already maintaining a high altitude and speed. This can lead to drastic data fluctuations or even data invalidation. In such cases, assigning it a high weight or maintaining its original weight would severely contaminate the final calculation results. Therefore, in the secondary correction, the weighting coefficient of the altimeter can be reduced, and other weighting coefficients can be normalized. The final vertical velocity is then calculated based on the corrected weighting coefficients. Furthermore, when the aircraft is in the cruise phase, the data provided by the altimeter is essentially invalid; therefore, its weighting coefficient can be directly set to 0, meaning it is not included in the vertical velocity calculation.

[0063] When the current flight phase is the approach phase, refer to Figure 2 As shown in Phase IV, during the approach phase, the aircraft's altitude gradually decreases, and the accuracy of the altitude data measured by the altimeter gradually improves, correspondingly enhancing the reliability of the altimeter's vertical velocity. Therefore, the weighting coefficient of the altimeter's vertical velocity can be dynamically adjusted based on real-time altitude data. The weighting coefficient is gradually increased as the altitude decreases to fully utilize its high precision advantage in low-altitude environments. By dynamically adjusting the weighting coefficient, the vertical velocities from other data sources are adjusted accordingly. The final vertical velocity is then calculated based on the second-corrected weighting coefficient, thereby improving the accuracy of the final vertical velocity calculation.

[0064] In one embodiment, the weighted fusion of the overall vertical velocity and the altimeter vertical velocity is performed according to a weighting coefficient, including: when the altitude data meets preset low-altitude conditions, dynamically increasing the weighting coefficient of the altimeter vertical velocity based on the altitude data, and solving the final vertical velocity based on the corrected weighting coefficient; when the altitude data meets preset high-altitude conditions, dynamically decreasing the weighting coefficient of the altimeter vertical velocity based on the altitude data, and solving the final vertical velocity based on the corrected weighting coefficient.

[0065] In one embodiment, the weighting coefficients of this application can be influenced not only by the flight phase but also dynamically adjusted in real time based on altitude data measured by an altimeter. This dual-dimensional dynamic adjustment mechanism effectively avoids the limitations of a single data source in specific environments. Furthermore, during the adjustment process, weight correction can be performed solely based on the flight phase or altitude data, or a combination of both can be used to achieve more precise control. In the preferred embodiment, for the case of combined correction, the weighting coefficients obtained from the flight phase correction can be used as the base weights, and then real-time corrections can be performed based on the data quality, attitude state, terrain / platform reflection conditions, and multi-source consistency of the altitude data. Calculating the final vertical velocity based on the dual-corrected weighting coefficients can significantly improve data robustness and calculation accuracy under complex operating conditions.

[0066] Altitude data can be processed in two ways. When the altitude data meets preset low-altitude conditions, the weighting coefficient of the altimeter's vertical velocity is dynamically increased based on the altitude data, and the final vertical velocity is calculated based on the corrected weighting coefficient. Low-altitude conditions refer to altitude data obtained from altitude measurements meeting both low altitude (below a preset altitude threshold) and low velocity (below a preset velocity threshold; this velocity can be either vertical or horizontal). Low-altitude conditions typically correspond to the approach or landing phase, where the altimeter is less affected by ground clutter, the altitude data is continuous and stable, and the measurement accuracy is significantly improved. In this case, the vertical velocity data provided by the altimeter can be fully trusted. It is corrected from its original weighting, giving it a higher weighting coefficient to suppress potential noise interference from other data sources and ensure the smoothness and reliability of the final vertical velocity calculation.

[0067] Conversely, if the altitude data meets the preset high-altitude conditions, the weighting coefficient of the altimeter's vertical velocity is dynamically reduced. High-altitude conditions typically correspond to the cruise or climb phase, where altitude data exhibits high values, large or frequent fluctuations, and abnormal jumps. In this case, the quality of the altitude data obtained by the altimeter deteriorates, and the reliability of the altimeter's vertical velocity decreases accordingly. Therefore, it is necessary to reduce or even eliminate the weighting of the altimeter's vertical velocity, relying instead on vertical velocities from other data sources to calculate the final vertical velocity, thus avoiding calculation errors caused by anomalies in a single data source. For high-altitude conditions, for example, a 100m altitude limit can be directly set. When the aircraft exceeds 100m, the data measured by the altimeter becomes essentially invalid. In this case, the altimeter's vertical velocity can be directly set to 0, thus excluding it from the final vertical velocity calculation and ensuring the validity of the calculation.

[0068] It is understandable that the various weight correction methods described above all need to be processed according to the normalization principle to ensure that the sum of the weights of each data source is constant at 1, in order to maintain the mathematical stability of the solution model. Furthermore, this application mentions that during the weight correction process, the vertical velocity weights of one or more data sources may be reset to zero, that is, the contribution of that data source to the final solution result is completely eliminated. This adjustment method needs to be completed in a gradual manner to avoid abrupt changes in the final vertical velocity solution value, ensuring continuous and stable vertical control of the aircraft.

[0069] The calculated final vertical velocity is output to the flight control system, navigation guidance system, and avionics display system for vertical takeoff altitude control, hovering altitude maintenance, near-ground descent rate control, and vertical guidance during landing. Stable combined vertical velocity output improves the aircraft's altitude control accuracy, landing smoothness, and operational safety during vertical takeoff and landing.

[0070] The vertical velocity calculation method for an aircraft provided in this application includes the following steps: performing validity preprocessing on the measured altitude obtained by an altimeter to obtain altitude data; calculating the vertical velocity of the altimeter based on the altitude data; obtaining the composite vertical velocity and the current flight stage, and determining the weighting coefficients of the composite vertical velocity and the altimeter vertical velocity based on the current flight stage; weighted fusing the composite vertical velocity and the altimeter vertical velocity according to the weighting coefficients to calculate and output the final vertical velocity. Therefore, this application no longer simply uses the altitude measurement data directly for display, but uses the altimeter as a highly reliable near-ground altitude source for the vertical takeoff and landing (VTOL) phase. Through specialized vertical velocity calculation and fusion logic, it is transformed into vertical velocity information that can be used for navigation and flight control. The fusion weights of the multi-source vertical velocities are dynamically adjusted in different flight stages, transforming altitude change information into a stable measured vertical velocity, and dynamically weighted and fused with GPS azimuth velocity, atmospheric combined vertical velocity, and inertial vertical velocity to form a continuous, reliable, and smooth combined vertical velocity output, thereby improving the near-ground vertical control accuracy, descent rate control stability, and VTOL safety of the aircraft. This invention enables the altimeter to not only measure altitude but also calculate vertical velocity information from the altitude change rate, becoming a crucial input source for combined vertical velocity. This improves near-ground vertical control accuracy, increases the utilization rate of various aircraft equipment, and enhances the system's robustness in complex environments. The altimeter can be a laser rangefinder, allowing for flexible configuration based on different eVTOL aircraft models, takeoff and landing platforms, and operational scenarios. This enhances the adaptability and protection range of the solution, making it easier to promote and possessing better commercial prospects. In calculating the final vertical velocity, this application employs a smooth differential algorithm to calculate the altimeter's vertical velocity, rather than direct point-by-point differential. This effectively reduces high-frequency noise and spike errors during the differentiation process, resulting in a smoother and more stable altimeter vertical velocity, making it more suitable for participation in flight control and navigation fusion. This application dynamically adjusts the fusion weights of altimeter vertical velocity, GPS azimuth velocity, atmospheric combined vertical velocity, and inertial vertical velocity according to different flight phases such as vertical takeoff, hovering, near-ground descent, and landing. This enables the combined vertical velocity to adapt to the vertical control requirements of eVTOL vertical takeoff and landing, avoiding a decline in control performance due to the failure or increased error of a single vertical velocity source.

[0071] Figure 3 An internal structural diagram of the aircraft in one embodiment is shown. Figure 3 As shown, the device includes: a processor 310 and a memory 311 storing a computer program; wherein, Figure 3 The processor 310 shown in the diagram does not indicate that there is only one processor 310, but only indicates the positional relationship of the processor 310 relative to other devices. In practical applications, there can be one or more processors 310; similarly, Figure 3The memory 311 illustrated herein has the same meaning, that is, it is only used to indicate the positional relationship of memory 311 relative to other devices. In practical applications, there can be one or more memories 311. When the processor 310 runs the computer program, the method applied to the above-mentioned device is implemented.

[0072] The device may also include at least one network interface 312. The various components of the device are coupled together via a bus system 313. It is understood that the bus system 313 is used to implement communication between these components. In addition to a data bus, the bus system 313 includes a power bus, a control bus, and a status signal bus. However, for clarity, in... Figure 3 The general designated all buses as Bus System 313.

[0073] The memory 311 can be volatile memory or non-volatile memory, or both. Non-volatile memory can be read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), ferromagnetic random access memory (FRAM), flash memory, magnetic surface memory, optical disc, or compact disc read-only memory (CD-ROM); magnetic surface memory can be disk storage or magnetic tape storage. Volatile memory can be random access memory (RAM), used as an external cache. By way of example, but not limitation, many forms of RAM are available, such as Static Random Access Memory (SRAM), Synchronous Static Random Access Memory (SSRAM), Dynamic Random Access Memory (DRAM), Synchronous Dynamic Random Access Memory (SDRAM), Double Data Rate Synchronous Dynamic Random Access Memory (DDRSDRAM), Enhanced Synchronous Dynamic Random Access Memory (ESDRAM), SyncLink Dynamic Random Access Memory (SLDRAM), and Direct Rambus Random Access Memory (DRRAM).The memory 311 described in the embodiments of the present invention is intended to include, but is not limited to, these and any other suitable types of memory.

[0074] The memory 311 in this embodiment of the invention is used to store various types of data to support the operation of the device. Examples of this data include: any computer programs used to operate on the device, such as operating systems and applications; contact data; phonebook data; messages; pictures; videos, etc. The operating system includes various system programs, such as the framework layer, core library layer, driver layer, etc., used to implement various basic services and handle hardware-based tasks. Applications can include various applications, such as media players, browsers, etc., used to implement various application services. Here, the program implementing the method of this embodiment of the invention can be included in the application.

[0075] Based on the same inventive concept as the foregoing embodiments, this embodiment also provides a computer-readable storage medium storing a computer program. The computer-readable storage medium can be a magnetic random access memory (FRAM), a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), a flash memory, a magnetic surface memory, an optical disc, or a compact disc read-only memory (CD-ROM), etc.; it can also be various devices including one or any combination of the above-mentioned memories, such as mobile phones, computers, tablet devices, personal digital assistants, etc. When the computer program stored in the computer-readable storage medium is run by a processor, it implements the above method. For the specific steps implemented when the computer program is executed by the processor, please refer to [link to relevant documentation]. Figure 1 The description of the illustrated embodiments will not be repeated here.

[0076] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0077] In this document, the terms “comprising,” “including,” or any other variations thereof are intended to cover non-exclusive inclusion, which includes not only the elements listed but also other elements not expressly listed.

[0078] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A method for calculating the vertical velocity of an aircraft, characterized in that, The method includes the following steps: After performing validity preprocessing on the measured heights obtained by the altimeter, the height data is obtained; The vertical velocity of the height measuring instrument is calculated based on the height data. Obtain the composite vertical velocity and the current flight phase, and determine the weighting coefficients of the composite vertical velocity and the altimeter vertical velocity based on the current flight phase; The combined vertical velocity and the vertical velocity of the height measuring instrument are weighted and fused according to the weighting coefficients to calculate the final vertical velocity and output it.

2. The method for calculating the vertical velocity of an aircraft as described in claim 1, characterized in that, After performing validity preprocessing on the measured height obtained by the altimeter, the resulting height data includes: The validity screening criteria are determined based on the current flight phase and current attitude state. The validity screening criteria include the effective measurement range, the rate of change threshold, and the tolerance for abnormal jumps. The measured height is filtered and anomalies are removed in real time based on the validity screening criteria. The processed measured height is used as the height data.

3. The method for calculating the vertical velocity of an aircraft as described in claim 1, characterized in that, The calculation of the vertical speed of the height measuring instrument based on the height data includes: According to a preset time window, the height data is divided into multiple height sub-data segments; Calculate the height representative value for each segment of the height sub-data, where the height representative value is any one of the mean, median, or weighted average of the height sub-data; The vertical speed of the height measuring instrument is obtained by differentiating the representative height value with the preset time window.

4. The method for calculating the vertical velocity of an aircraft as described in claim 1, characterized in that, The calculation of the vertical speed of the height measuring instrument based on the height data includes: Determine the current flight phase; When the current flight phase is the vertical takeoff phase, the altitude data is divided into multiple segments of altitude sub-data within a first time window, and the vertical velocity of the altitude measuring instrument is calculated; the length of the first time window is shorter than the length of the time window corresponding to other flight phases. When the current flight phase is the hovering phase, the altitude data is smoothed; the vertical speed of the altimeter is calculated using the processed altitude data. When the current flight phase is the near-ground descent phase, data points in the altitude data that do not meet the descent conditions are removed; the vertical speed of the altitude measuring instrument is calculated based on the removed altitude data. When the current flight phase is the vertical landing phase, data points with abnormal jumps in the altitude data are removed; the vertical speed of the altitude measuring instrument is calculated based on the removed altitude data.

5. The method for calculating the vertical velocity of an aircraft as described in claim 1, characterized in that, The process of acquiring the composite vertical velocity and the current flight phase, and determining the weighting coefficients for the composite vertical velocity and the altimeter vertical velocity based on the current flight phase, includes: The reliability of calculating the combined vertical velocity and the altimeter vertical velocity based on the current flight phase; Based on the reliability of the composite vertical velocity and the vertical velocity of the height measuring instrument, the weighting coefficients of the composite vertical velocity and the vertical velocity of the height measuring instrument are calculated respectively.

6. The method for calculating the vertical velocity of an aircraft as described in claim 5, characterized in that, The combined vertical velocity includes at least one of the following: celestial velocity, atmospheric combined vertical velocity, and inertial calculated vertical velocity. The reliability of calculating the combined vertical velocity and the altimeter vertical velocity based on the current flight phase includes: The reliability evaluation factors for the comprehensive vertical velocity and the vertical velocity of the height measuring instrument are obtained respectively. The reliability evaluation factors include at least one of the following: height range, sensor working status, data continuity, data change rate, attitude change, and environmental influence. The data consistency rate among the celestial velocity, the atmospheric combined vertical velocity, the inertial calculated vertical velocity, and the altimeter vertical velocity is calculated based on the aforementioned reliability evaluation factors. Data sources with a data consistency rate lower than a preset threshold are removed, and the remaining data consistency rate is used as the reliability of the corresponding vertical velocity.

7. The method for calculating the vertical velocity of an aircraft as described in claim 1, characterized in that, The weighted fusion of the composite vertical velocity and the vertical velocity of the height measuring instrument according to the weighting coefficient includes: Determine the current flight phase; When the current flight phase is any of the vertical takeoff phase, hovering phase, and / or vertical landing phase, the weighting coefficient of the vertical velocity of the altimeter is increased and then used to solve for the final vertical velocity. When the current flight phase is the end of the departure phase and / or the beginning of the approach phase, the weighting coefficient of the vertical velocity of the altimeter is reduced and then used to solve for the final vertical velocity. When the current flight phase is the approach phase, the weighting coefficient of the vertical velocity of the altimeter is dynamically corrected based on the altitude data, and the final vertical velocity is calculated based on the corrected weighting coefficient.

8. The method for calculating the vertical velocity of an aircraft as described in claim 1, characterized in that, The weighted fusion of the composite vertical velocity and the vertical velocity of the height measuring instrument according to the weighting coefficient includes: When the altitude data meets the preset low-altitude conditions, the weighting coefficient of the vertical velocity of the altitude measuring instrument is dynamically increased based on the altitude data, and the final vertical velocity is calculated based on the corrected weighting coefficient. When the altitude data meets the preset high-altitude conditions, the weighting coefficient of the vertical velocity of the altitude measuring instrument is dynamically reduced based on the altitude data, and the final vertical velocity is calculated based on the corrected weighting coefficient.

9. An aircraft, characterized in that, Including processor and memory; The processor is configured to execute a computer program stored in the memory to implement the method as described in any one of claims 1 to 8.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed by a processor, implements the method as described in any one of claims 1 to 8.

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