A taws operation phase determination method suitable for evtol

Abstract

The application provides a TAWS running stage judgment method suitable for eVTOL, belongs to the technical field of electric vertical take-off and landing aircraft, and specifically comprises the following steps: calculating elevation data ASL above sea level and elevation data AGL above ground by combining a barometric height value, a GNSS elevation value, radio altitude, and a runway / terrain / obstacle database; calculating the vertical speed of an aircraft climbing rate by fusing an inertial navigation system IRS, an atmospheric data computer ADC and a global satellite navigation system GNSS; comprehensively judging the stage of the current aircraft by referring to a flight stage state machine, improving the multi-scene availability of the algorithm, containing data loss, data calculation offset and the like, increasing the redundancy of data, and thus improving the operation logic confidence of the equipment.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of electric vertical take-off and landing aircraft, in particular to a TAWS operating phase determination method suitable for eVTOL. BACKGROUND

[0002] The mainstream aircraft equipped with terrain awareness and warning system are manned helicopters and manned fixed-wing aircraft, and their corresponding product standards are CTSO-C194 and CTSO-C151d. Most products on the market have complete functions and mature technology, but with the outbreak of "low-altitude economy" demand such as urban air traffic, sightseeing tourism, cargo transportation and emergency rescue, the demand for TAWS of eVTOL and other aircraft is also growing.

[0003] The operating characteristics of TAWS are to automatically activate the corresponding functions according to the flight phase of the aircraft, so as to remind the pilot that the current flight situation has a threat of crashing into the ground. The determination of flight phase is the core logic of TAWS. The flight phase of eVTOL is obviously different from that of helicopters and fixed-wing aircraft. If the existing flight phase determination criteria of helicopters or fixed-wing aircraft are simply used, there will be certain limitations, which are specifically manifested in that the different aircraft configurations and flight profiles are easy to cause the enablement logic to be mixed, in addition, the data transmission of low-altitude sensors is easy to be lost or mutated, which also causes the error determination of flight phase. SUMMARY

[0004] Therefore, the present application provides a TAWS operating phase determination method suitable for eVTOL, which solves the problems in the prior art, improves the multi-scene usability of the algorithm, contains data loss, data calculation offset, etc., increases the redundancy of data, and thus improves the operation logic confidence of the equipment.

[0005] The TAWS operating phase determination method suitable for eVTOL provided by the present application adopts the following technical solution:

[0006] A TAWS operating phase determination method suitable for eVTOL, comprising:

[0007] Step 1, acquiring on-board avionics sensor data and performing validity processing, calculating the altitude parameter in the radio altitude invalid state and the data validity matrix A of the multi-source vertical speed;

[0008] Step 2, calculating the distance between the current position and the runway according to the coordinate position of GNSS combined with the position data of the runway database, determining the position relationship between the aircraft and the airport, when the aircraft is in the periphery of the airport, executing step 3, otherwise executing step 4;

[0009] Step 3, calculate the radio altitude above ground level in valid or invalid state by using the elevation data of runway database of terrain awareness and warning system (TAWS) ;

[0010] Step 4, calculate the elevation data in GNSS valid or invalid state by using the terrain / obstacle data, RNP, ANP and star number information, and use the time accuracy of avionics parameters to maintain the characteristics, and combine the pressure altitude compensation to calculate the aircraft height above sea level in non-runway surrounding flight , wherein the terrain / obstacle data is obtained from the terrain awareness and warning system (TAWS);

[0011] Step 5, define the data influence factor based on the data update period, and combine the data validity matrix A of multi-source vertical speed to calculate the aircraft climb rate by weighted fusion

[0012] Step 6, calculate the aircraft height above ground in the whole scene, and calculate the current TAWS determination running stage by the designed flight stage state machine diagram.

[0013] Optionally, the step 1 specifically comprises:

[0014] Step 1.1, collect the aircraft and flight state data from multi-source avionics, and the collected data includes longitude, latitude, elevation, ground speed, skyward speed from global navigation satellite system (GNSS), pressure altitude change rate and pressure altitude from air data computer (ADC), required navigation performance (RNP) and actual navigation performance (ANP) from flight management system (FMS), radio altitude from radio altimeter (LLRA), air-ground signal from flight control system (FCS), and inertial vertical speed and three-axis acceleration from inertial navigation system (IRS);

[0015] Step 1.2, determine the validity of radio altitude data according to the period refresh state and value size of radio altitude, and the criterion for determining the validity of data is that the data is invalid if any of the following conditions is met: the height value is not refreshed for 5 periods, and the value range exceeds the effective range, if it is determined to be invalid, the elevation parameter , represents the pressure altitude from ADC;

[0016] Step 1.3, respectively determine the validity of skyward speed from GNSS, pressure altitude change rate from ADC, and inertial vertical speed from IRS, and the criterion for determining invalid data is that the value is not refreshed for 5 periods or the value exceeds the effective range, and a 1-row-3-column matrix A is used to represent the data validity, the first column represents the skyward speed, the second column represents the pressure altitude change rate, and the third column represents the inertial vertical speed, if valid, the corresponding value is 1, and if invalid, the value is 0. ​

[0017] Optionally, the step 2 specifically includes:

[0018] According to the coordinate position of GNSS, combined with the runway database position data, the distance between the current position and the runway is calculated , the smallest distance is selected Determine whether the current is above the runway, when The aircraft is determined to be above the runway, step 3 is executed, otherwise step 4 is executed, wherein The coefficient is determined by the characteristics of the airport.

[0019] Optionally, the step 3 specifically includes:

[0020] Step 3.1, analyze the content of the runway database, index the elevation position information, get the runway elevation of the area where the aircraft is located , the height of the aircraft above sea level is calculated by radio height ; ;

[0021] Step 3.2, combined with step 1.2, the height of the aircraft above sea level when the radio height is valid or invalid, the height of the aircraft above sea level when the aircraft is flying in the runway peripheral scene is calculated When the radio height data is valid , that is, When the radio height data is invalid .

[0022] Optionally, the step 4 specifically includes:

[0023] Step 4.1, analyze the terrain / obstacle data, get the terrain elevation information, assemble the map block according to the RNP data, the specific way is: when , the map block is assembled in 3x3 way, the average value of 9 map elevation data is calculated as the elevation value in this area ; When , the current involved map block elevation needs to be indexed as , wherein The coefficient represents the specific numerical value, According to the scene dynamic adjustment;

[0024] Step 4.2, introduce ANP to calculate navigation error , combined with the number of stars of GNSS, determine the value of elevation element parameter , the specific condition is: when the number of stars is less than Or err> 0, it is considered that the data accuracy of navigation source GNSS does not meet the requirements, radio height is used at this time get , otherwise use GNSS elevation data as , i.e. where k is directly from GNSS;

[0025] Step 4.3, using the elevation data calculated in step 4.2 compensate to get the height of the aircraft above sea level at current time t using barometric height compensation , where is the filter time constant at time t, is the Laplace operator.

[0026] Optionally, the step 5 specifically comprises:

[0027] Step 5.1, according to the data update period, calculate the data influence factor matrix of the skyward velocity, the ADC barometric height change rate, and the inertial vertical velocity of the IRS derived from GNSS ; is a 1-row 3-column matrix, the first column represents the skyward velocity, the second column represents the barometric height change rate, and the third column represents the inertial vertical velocity, and the specific calculation formula is: where i represents the data source selection, -1, 2, and 3 represent the vertical velocities transmitted by GNSS, ADC, and IRS respectively, is the data refresh period.

[0028] Step 5.2, combined with step 1.3, calculate the weighted coefficient considering the data influence factor and the data effectiveness The final vertical climb rate of the aircraft weighted average is calculated as follows:

[0029] ;

[0030] wherein , , represent the vertical velocities from GNSS, ADC, and IRS respectively.

[0031] Optionally, the step 6 specifically comprises:

[0032] Step 6.1, according to step 4.3, calculate the height of the aircraft above the ground in non-runway peripheral flight ; the height of the aircraft above the ground in the runway peripheral flight is known from step 3 , to get the elevation data of the aircraft above the ground in the full scene;

[0033] Step 6.2, from the eVTOL flight profile, combined with the aircraft performance and mission altitude, design the flight phase state machine transition relationship;

[0034] Step 6.3, the parameters obtained in step 5.2 and step 6.1 are substituted into the flight phase state machine transition relationship in step 6.2 to obtain the running phase of the current time TAWS determination.

[0035] In summary, the present application includes the following beneficial technical effects:

[0036] The method of the present application is directional design, and has strong specificity. Compared with the traditional TAWS device flight phase judgment method, the present application fully considers the flight characteristics and scene categories of eVTOL aircraft, and formulates a flight phase transition mechanism with eVTOL specific properties.

[0037] The method of the present application is data-level fusion, and has high usability. The present application mainly designs algorithms for two important elements of flight phase determination, i.e., height above ground and aircraft climb rate, comprehensively considers factors such as cycle, long-term accuracy, and short-term accuracy of avionics data, and finally fuses and calculates new avionics elements. This method can significantly improve the usability of data while accurately calculating the required parameters.

[0038] The method of the present application is hierarchical and scene-based, and has excellent execution. The present application calculates the required avionics parameters in parallel, and the lag of one path does not affect the rest of the operation. The pre-designed flight phase state machine module is introduced in the final flight phase calculation, which can speed up the execution efficiency of the algorithm. BRIEF DESCRIPTION OF DRAWINGS

[0039] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0040] Figure 1 The present application is a TAWS running phase determination method flowchart suitable for eVTOL;

[0041] Figure 2 The present application is a flight phase state machine transition relationship diagram;

[0042] Figure 3 The present application is a terrain awareness and warning system flight phase determination algorithm architecture diagram. DETAILED DESCRIPTION

[0043] The embodiments of the present application will be described in detail below with reference to the drawings.

[0044] Following, the embodiments of the present application are described through specific examples, and other advantages and effects of the present application can be easily understood by those skilled in the art from the disclosure. Obviously, the described embodiments are only a part of the embodiments of the present application, not all. The present application can also be implemented or applied by other different specific embodiments, and various modifications or changes can be made to the details in the specification without departing from the spirit of the present application. It should be noted that the following embodiments and features in the embodiments can be combined with each other without conflict. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0045] It should be noted that the various aspects of the embodiments described below are within the scope of the appended claims. It should be apparent that the aspects described herein can be embodied in a wide variety of forms and that any specific structure and / or function described herein is merely illustrative. Based on the teachings herein one skilled in the art should appreciate that an aspect described herein can be implemented independently of any other aspects and that two or more of these aspects can be combined in various ways. For example, an apparatus can be implemented or a method can be practiced using any number of the aspects set forth herein. In addition, such an apparatus can be implemented or such a method can be practiced using other structure and / or functionality in addition to or other than one or more of the aspects set forth herein.

[0046] It should also be noted that the drawings included in the following embodiments are only to illustrate the basic concept of the present application, and only show the components related to the present application in the drawings, not drawn according to the number, shape and size of the components when actually implemented, the actual implementation of each component can be a random change in shape, number and proportion, and the layout of the components can be more complex.

[0047] In addition, in the following description, specific details are provided in order to facilitate a thorough understanding of examples. However, one skilled in the art will understand that the aspects described can be practiced without these specific details.

[0048] The embodiments of the present application provide a TAWS running phase determination method suitable for eVTOL.

[0049] As shown in Figure 1 A TAWS running phase determination method suitable for eVTOL includes:

[0050] Step 1, acquiring on-board avionics sensor data and performing validity processing, calculating the altitude parameter in the radio height invalid state And the data validity matrix A of the multi-source vertical speed.

[0051] Step 2, according to the coordinate position of GNSS, combined with the runway database position data, calculate the distance between the current position and the runway, determine the position relationship between the aircraft and the airport, when the aircraft is in the periphery of the airport, execute step 3, otherwise execute step 4.

[0052] Step 3, using the elevation data of the runway database of the terrain awareness and warning system TAWS, calculate the radio height of the aircraft above the ground height in the effective or ineffective state of radio height .

[0053] Step 4, through the terrain / obstacle data, RNP, ANP and the number of stars information, calculate the elevation data in the effective or ineffective state of GNSS, use the time accuracy maintenance characteristics of avionics parameters, combined with the pressure altitude compensation to calculate the height of the aircraft above sea level in the non-runway periphery , wherein the terrain / obstacle data is obtained from the terrain awareness and warning system TAWS.

[0054] Step 5, define the data influence factor based on the data update period, and calculate the aircraft climb rate by weighted fusion based on the data validity matrix A of multi-source vertical speed.

[0055] Step 6, calculate the aircraft height above ground elevation data in the whole scene, and calculate the current TAWS determination running phase by designing the flight phase state machine diagram.

[0056] The application calculates the height above sea level ASL and the height above ground AGL by combining the pressure altitude value, GNSS elevation value, radio height, runway / terrain / obstacle database; uses the vertical speed of inertial navigation system IRS, atmospheric data computer ADC and global satellite navigation system GNSS to calculate the aircraft climb rate; refers to the flight phase state machine to comprehensively judge the current aircraft phase, so as to achieve the goal of improving data availability.

[0057] The running phase of the TAWS calculation of the application is only used for the internal function of TAWS, which is different from the flight phase defined by the aircraft.

[0058] The step 1 specifically includes:

[0059] Step 1.1, collect aircraft and flight state data from multi-source avionics for subsequent step calculation, the collected data includes longitude, latitude, elevation, ground speed, skyward speed from global satellite navigation system GNSS, pressure altitude rate, pressure altitude from atmospheric data computer ADC, required navigation performance RNP, actual navigation performance ANP from flight management system FMS, radio height from radio altimeter LLRA , air-ground signal of flight control system FCS, and inertial vertical speed and three-axis acceleration of inertial navigation system IRS.

[0060] Step 1.2, judging the validity of radio altitude data according to the period refresh state and value size of radio altitude, the criterion for judging data validity is that data is invalid if any of the following conditions is met: height values of 5 periods are not refreshed, and the value range exceeds the effective range. If it is judged to be invalid, the height parameter , represents the barometric altitude from the ADC; the refresh period and the effective range are defined by the equipment manufacturer.

[0061] Step 1.3, respectively judging the validity of the skyward speed from GNSS, the barometric altitude rate of change from ADC, and the inertial vertical speed of IRS, the criterion for judging data invalidity is that the value is not refreshed for more than 5 periods or the value exceeds the effective range. Use a 1-row 3-column matrix A to represent data validity, the first column represents skyward speed, the second column represents barometric altitude rate of change, and the third column represents inertial vertical speed. If valid, set the corresponding value to 1, and if invalid, set it to 0. The refresh period and the effective range are defined by the equipment manufacturer.

[0062] The step 2 specifically includes: calculating the distance between the current position and the runway according to the coordinate position of GNSS and combining the runway database position data selecting the smallest distance judging whether the current position is above the runway, when , it is determined that the aircraft is above the runway, and step 3 is executed, otherwise step 4 is executed, wherein, is a coefficient, and the size is determined by the characteristics of the airport, such as a smaller value should be used for a parking lot than for a general airport.

[0063] The step 3 specifically includes:

[0064] Step 3.1, parsing the content of the runway database, indexing the height position information, and obtaining the runway height of the area where the aircraft is located calculating the height of the aircraft above sea level by radio altitude .

[0065] Step 3.2, combining the height of the aircraft above sea level when the radio altitude is valid or invalid in step 1.2 to calculate the height of the aircraft above ground when the aircraft is flying in the runway periphery when the radio altitude data is valid , that is, when the radio altitude data is invalid .

[0066] The step 4 specifically includes:

[0067] Step 4.1: parse terrain / obstacle data, obtain terrain elevation information, and assemble map blocks based on RNP data to optimize computing resources. The specific method is as follows: , the map blocks are assembled in a 3x3 manner, and the average of the elevation data of the 9 blocks is calculated as the elevation value in this area ;when , you need to index the elevation of the map block currently involved as ,in is the coefficient, indicating the specific value. Dynamically adjust according to the scene.

[0068] Step 4.2: Introduce ANP to calculate navigation error , combined with the GNSS satellite number value, determine the elevation element parameters The specific conditions are: when the number of stars < If the err is greater than 0, the data accuracy of the navigation source GNSS is considered to be unsatisfactory. In this case, the radio altitude get Otherwise, use GNSS elevation data As ,Right now , where k are directly from GNSS.

[0069] Step 4.3, taking into account the pressure altitude The long-term accuracy is high and can be used For the elevation data calculated in step 4.2 Compensate and get the height of the aircraft above sea level after using the pressure altitude compensation at the current time t , ,in is the filtering time constant at time t, is the Laplace operator.

[0070] The step 5 specifically includes:

[0071] Step 5.1: Calculate the data impact factor matrix of the GNSS celestial velocity, ADC pressure altitude change rate, and IRS inertial vertical velocity based on the data update period. ; It is a matrix with 1 row and 3 columns. The first column represents the celestial velocity, the second column represents the rate of change of pressure altitude, and the third column represents the inertial vertical velocity. The specific calculation formula is: , where i represents the data source selection - 1, 2, and 3 represent the vertical rates of GNSS, ADC, and IRS transmissions, respectively. Data refresh period, refresh period defined by the device manufacturer.

[0072] Step 5.2, combined with step 1.3, the calculation of the comprehensive consideration data impact factor and the weighted coefficient of data validity , the final vertical climb rate of the aircraft is weighted average as shown in the following formula:

[0073] ; wherein, , , respectively from GNSS, ADC, IRS vertical rate.

[0074] The step 6 specifically includes:

[0075] Step 6.1, according to step 4.3, the height of the aircraft above the ground when the aircraft is in the non-runway periphery ; from step 3, the height of the aircraft above the ground when the aircraft is in the runway periphery , get the elevation data of the aircraft above the ground in the whole scene.

[0076] Step 6.2, starting from the eVTOL flight profile, combined with the aircraft performance and task height, the flight phase state machine transition relationship is designed, as shown in Figure 2 The specific logic of the flight phase state machine transition diagram is as follows: starting from the aircraft on the ground, after taking off and returning to the ground, it is explained that when the aircraft is on the ground, according to the air-ground signal, radio height, climb rate and ground speed, it is judged whether the aircraft reaches the vertical take-off stage; After the aircraft is in the vertical take-off stage, according to the AGL height, ground speed and forward acceleration, it is judged whether the aircraft reaches the climb transition stage; When the aircraft is in the climb transition stage, according to the airspeed and climb, it is judged whether the aircraft reaches the climb stage, and according to the ground speed and forward acceleration, it is judged whether the aircraft reaches the landing transition stage; When the aircraft is in the climb stage, according to the AGL height, it is judged whether the aircraft reaches the cruise stage, and according to the vertical acceleration and forward acceleration, it is judged whether the aircraft reaches the landing transition stage; When the aircraft is in the cruise stage, according to the AGL height, it is judged whether the aircraft reaches the descent stage; When the aircraft is in the descent stage, according to the AGL height, it is judged whether the aircraft reaches the cruise stage, and according to the climb rate and forward acceleration, it is judged whether the aircraft reaches the landing transition stage; When the aircraft is in the landing transition stage, according to the radio height and ground speed, it is judged whether the aircraft reaches the vertical landing stage, and according to the ground speed and forward acceleration, it is judged whether the aircraft reaches the climb transition stage; When the aircraft is in the vertical landing stage, according to the air-ground signal, radio height and climb rate, it is judged whether the aircraft reaches the ground stage, wherein the AGL height is the height of the aircraft above the ground.

[0077] Step 6.3, the parameters calculated in step 5.2 and step 6.1 are substituted into the transition relationship of the flight phase state machine in step 6.2, and the running phase of the current time TAWS determination can be obtained.

[0078] The application can be used in the terrain perception and warning system on manned platforms such as eVTOL or combined wings with helicopter and fixed-wing flight profiles, to provide protection for safe flight of the aircraft, and can also be used as a reference method for data fusion processing of avionics equipment.

[0079] As shown in Figure 3 The embodiment of the application also discloses a flight phase determination algorithm system of the terrain perception and warning system, which comprises a terrain elevation calculation module, an AGL calculation module and a flight phase decision module. The terrain elevation calculation module and the AGL calculation module collect aircraft and flight state data from multiple sources of avionics. The terrain elevation calculation module performs data processing, terrain data processing and obstacle data processing. The AGL calculation module performs multi-source height calculation, multi-source vertical speed error calculation and AGS and vertical speed calculation. The flight phase decision module executes step 6.3 to output the running phase of the current time TAWS determination.

[0080] The above is only a specific embodiment of the application, but the protection scope of the application is not limited thereto. Any person skilled in the art can easily think of changes or replacements within the technical range disclosed in the application, which should be covered within the protection scope of the application. Therefore, the protection scope of the application should be subject to the protection scope of the claims.

Claims

1. A TAWS operational phase determination method suitable for eVTOL characterized in that, The method comprises the following steps: Step 1, acquire airborne avionics sensor data and perform validity processing, calculate the altitude parameter under the invalid state of radio altitude and the data validity matrix A of multi-source vertical speed Step 2, according to the coordinate position of GNSS, combining the runway database position data, calculating the distance between the current position and the runway, determining the position relationship between the aircraft and the airport, when the aircraft is in the periphery of the airport, executing step 3, otherwise executing step 4; Step 3, using the elevation data from the runway database of the Terrain Awareness and Warning System (TAWS), calculate the radio altitude above ground level for the aircraft in the active or inactive state ; Step 4, calculate the height above sea level of the aircraft outside the runway perimeter by using the time accuracy maintenance characteristics of the avionics parameters, combining with the barometric height compensation calculation, through the terrain / obstacle data, RNP, ANP and the number of stars information, to obtain the height data in the GNSS effective or invalid state wherein the terrain / obstacle data is obtained from a terrain awareness and warning system (TAWS). Step 5, defining the data influence factor based on the data update period, and calculating the aircraft climb rate by weighted fusion combining the data validity matrix A of the multi-source vertical speed; Step 6, calculating the height data of the aircraft above the ground in the whole scene, and obtaining the running stage of the current TAWS determination through the designed flight phase state machine diagram.

2. The TAWS operating phase determination method suitable for eVTOL of claim 1, wherein, The step 1 specifically comprises: Step 1.1: Collect aircraft and flight status data from multiple avionics sources. The collected data includes latitude and longitude, altitude, ground speed, and celestial speed from the Global Navigation Satellite System (GNSS), pressure altitude rate of change and pressure altitude from the Atmospheric Data Computer (ADC), required navigation performance (RNP) and actual navigation performance (ANP) from the Flight Management System (FMS), and radio altitude from the Radio Altimeter (LLRA). , the air-ground signal of the flight control system FCS, and the inertial vertical velocity and three-axis acceleration of the inertial navigation system IRS; Step 1.2, according to the periodic refresh state of radio height, the value size determines the validity of radio height data. The criterion for determining the validity of data is that if any of the following conditions is met, the data is invalid: the height value is not refreshed for 5 periods, the value range exceeds the effective range. If it is determined to be invalid, the height parameter , represents the barometric height from the ADC; Step 1.3, respectively judging the validity of the skyward speed from GNSS, the pressure altitude change rate of ADC and the inertial vertical speed of IRS, and the criterion for judging invalid data is that the value is not refreshed for more than 5 cycles or the value exceeds the action range, and a 1-row 3-column matrix A is used to represent the data validity, the first column represents the skyward speed, the second column represents the pressure altitude change rate, and the third column represents the inertial vertical speed, if valid, the corresponding value is 1, if invalid, the value is 0.

3. The TAWS operating phase determination method suitable for eVTOL of claim 1, wherein, The step 2 specifically comprises: According to the coordinate position of GNSS, combined with runway database position data, the distance between the current position and the runway is calculated , the smallest distance is selected , it is judged whether the current is above the runway, when , it is determined that the aircraft is above the runway, step 3 is executed, otherwise step 4 is executed, wherein is a coefficient, the size is determined by the characteristics of the airport.

4. The TAWS operating phase determination method suitable for eVTOL of claim 2, wherein, The step 3 specifically comprises: Step 3.1: Parse the runway database, index the elevation information, and obtain the runway elevation in the area where the aircraft is located. , by radio altitude Calculate the aircraft's altitude above sea level ; Step 3.2, in combination with step 1.2, the height of the aircraft above sea level is calculated when the radio altitude is valid or invalid for the aircraft flying in the runway- surrounding scenario, thus the height of the aircraft above ground is calculated for the aircraft flying in the runway- surrounding scenario when the radio altitude data is valid i.e. when the radio altitude data is invalid .

5. The TAWS operating phase determination method suitable for eVTOL of claim 1, wherein, The step 4 specifically comprises: Step 4.1, parsing terrain / obstacle data, obtaining terrain elevation information, assembling map blocks according to RNP data, in particular: when , the map blocks are assembled in a 3x3 manner, and the average of the elevation data of the 9 map blocks is calculated as the elevation value in this area ; when , the elevation of the current involved map block needs to be indexed as , wherein is a coefficient, representing the specific numerical size, which is dynamically adjusted according to the scene; Step 4.2, introduce ANP to calculate navigation error , combine the number of stars of GNSS to determine the value of the height element parameter , specific conditions are: when the number of stars < 3, or err > 0, it is considered that the data accuracy of the navigation source GNSS does not meet the requirements, at this time the radio height is obtained , otherwise the GNSS height data is used , that is , where k is directly from GNSS;​​ Step 4.3, using the altitude data computed in step 4.2 is compensated to obtain the height of the aircraft above sea level at the current time t using barometric altitude compensation , where is the filter time constant at time t, is the Laplacian operator.

6. The TAWS operating phase determination method suitable for eVTOL of claim 5, wherein, The step 5 specifically comprises: Step 5.1, calculating the data influence factor matrix of the skyward velocity from GNSS, the pressure altitude rate of change of ADC, and the inertial vertical velocity of IRS according to the data update period ; is a 1-row 3-column matrix, the first column represents the skyward velocity, the second column represents the pressure altitude rate of change, and the third column represents the inertial vertical velocity, and the specific calculation formula is: , wherein i represents the data source selection, -1, 2, and 3 respectively represent the vertical velocities transmitted by GNSS, ADC, and IRS, is the data refresh period; Step 5.2, combined with step 1.3, the calculation of the data impact factor and the weighted coefficient of data validity considering the comprehensive consideration The final vertical climb rate weighted average of the aircraft is calculated as follows: ； wherein, , , respectively denote the vertical rates from GNSS, ADC, IRS.

7. The TAWS operating phase determination method suitable for eVTOL of claim 6, wherein, The step 6 specifically comprises: Step 6.1, calculate the non-runway perimeter aircraft height above ground from step 4.3 ; and the runway perimeter aircraft height above ground from step 3 , to obtain the aircraft height above ground data for the entire scene; Step 6.2, starting from the eVTOL flight profile, combining the aircraft performance and task height, and designing the flight phase state machine conversion relationship; Step 6.3, substituting the parameters obtained in steps 5.2 and 6.1 into the flight phase state machine conversion relationship in step 6.2, to obtain the running stage of the current TAWS determination.

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