Urban air traffic energy-saving path planning method and system

Abstract

The invention belongs to the technical field of aircraft control, and relates to an urban air traffic energy-saving path planning method and system, and the method comprises the following steps: collecting Doppler frequency shift data and thermal infrared radiation data in front of a flight path of an aircraft, and generating an airflow characteristic data packet; analyzing the airflow characteristic data packet to generate an available vortex target; receiving an available eddy current target, and obtaining an asymmetric thrust vector preset instruction according to a rotation direction parameter of the available eddy current target; when the aircraft arrives at the coupling point, an asymmetric thrust vector preset instruction is executed, and an aircraft rotor system is regulated and controlled to manufacture and release coupling vortexes; monitoring a machine body vibration spectrum and a motor working current in real time, and generating an eddy current locking confirmation signal; the output power of the rotor wings is adjusted, and an energy replacement flight instruction is generated and executed; according to the invention, the problem that unnecessary energy waste is caused by continuous confrontation instead of effectively utilizing the environment in the traditional control method is solved.

Description

Technical Field

[0001] This invention belongs to the technical field of aircraft control and relates to an energy-saving route planning method and system for urban air traffic. Background Technology

[0002] Currently, the core problem with urban aircraft lies in their limited range, which restricts their application in urban air traffic, logistics, and other fields. The urban low-altitude environment is usually accompanied by unstable and variable complex airflow caused by the distribution of buildings. In order to maintain their own attitude stability, aircraft need to frequently adjust the rotor output power, a process that consumes some additional energy.

[0003] Existing technologies generally focus on optimizing the energy efficiency of the aircraft itself and flight path planning. Traditional methods typically treat airflow in the external environment, such as gusts and turbulence, as negative disturbances that need to be overcome. The main task of the flight control system is to use sensors to monitor deviations in flight attitude and quickly and forcefully perform reverse compensation, consuming its own energy to offset the unstable effects of the environment, without considering the possibility of obtaining energy from the environment.

[0004] The main drawback of traditional methods lies in their singular and adversarial energy utilization. By consuming energy to counteract environmental disturbances, the aircraft's energy consumption increases in complex airflow environments, significantly reducing its range. This method ignores the potential energy contained in the localized, small-scale stable eddies prevalent in urban canyons, treating all non-uniform airflows as obstacles to be overcome rather than usable resources. Therefore, traditional control methods not only fail to effectively utilize the environment but also cause unnecessary energy waste due to continuous adversarial interactions. Summary of the Invention

[0005] In a first aspect, the present invention provides an energy-saving route planning method for urban air traffic, employing the following technical solution:

[0006] A method for energy-saving route planning for urban air traffic includes the following steps:

[0007] S1. Collect Doppler frequency shift data and thermal infrared radiation data in front of the aircraft's flight path to generate airflow characteristic data packets;

[0008] S2. Analyze the airflow characteristic data package, identify and lock specific natural airflows based on preset turbulence thresholds and preset energy thresholds, and generate usable vortex targets containing their three-dimensional coordinates and rotation direction.

[0009] S3. Receive the available vortex target, and based on its rotation direction parameters, generate rotor control commands in reverse through a preset coupling control law to obtain a preset command for asymmetric thrust vector.

[0010] S4. When the aircraft arrives at the coupling point calculated based on the location of the available vortex target, execute the preset command for the asymmetric thrust vector to control the aircraft rotor system to generate and release the coupling vortex.

[0011] S5. Real-time monitoring of fuselage vibration spectrum and motor operating current; when coupled vortex and specific natural airflow form a composite vortex field, capture characteristic changes to generate vortex lock confirmation signal.

[0012] S6. In response to the eddy current lock confirmation signal, adjust the rotor output power and generate and execute energy replacement flight commands based on the feedback of the fuselage vibration spectrum and motor operating current.

[0013] A further aspect of the present invention generates an airflow characteristic data package, comprising the following steps:

[0014] The airborne high-frequency miniature Doppler photoradar is activated to scan the target airspace, acquire the Doppler frequency shift data of the returned laser signal, and analyze the dynamic morphology information accordingly.

[0015] The thermal infrared sensor array is activated to simultaneously measure the temperature difference between the target airspace and the surrounding environment, and energy intensity information is quantified and generated.

[0016] The dynamic morphology information and energy intensity information are spatiotemporally aligned to generate airflow characteristic data packages.

[0017] A further aspect of the present invention generates a usable eddy current target, comprising the following steps:

[0018] Receive airflow characteristic data packets and calculate the distribution variance of Doppler frequency shift data;

[0019] The distribution variance is compared with a preset turbulence threshold to determine the stability of the airflow structure;

[0020] The temperature difference calculated from thermal infrared radiation data is compared with a preset energy threshold to determine the value of airflow energy.

[0021] By locking onto a specific natural airflow that simultaneously satisfies both structural stability and energy value criteria, its three-dimensional coordinates and rotation direction parameters are extracted to generate a usable vortex target.

[0022] In a further aspect of the present invention, the coupling control law is based on the input natural eddy current rotation direction, and the rotor control command that can generate a reverse rotation torque is derived in reverse.

[0023] A further aspect of the present invention involves calculating the coupling point, including the following steps:

[0024] Receive the current speed and position of the aircraft; combine the three-dimensional coordinates of the available vortex target with the preset vortex formation time to calculate and generate the coupling point.

[0025] A further aspect of the present invention involves forming a coupled vortex, comprising the following steps:

[0026] The rotor assembly on one side of the aircraft is commanded to increase its rotational speed, while the rotor assembly on the other side is commanded to decrease its rotational speed, thereby generating an asymmetric downwash airflow.

[0027] The asymmetric downwash airflow is used to form coupled vortices by curling beneath the aircraft.

[0028] A further aspect of the present invention generates an eddy current locking confirmation signal, comprising the following steps:

[0029] By continuously monitoring the vibration spectrum of the fuselage using fuselage vibration sensors, coupling is determined to occur when the spectrum changes from a high-frequency state to a low-frequency state.

[0030] The operating current of each rotor motor is monitored synchronously. When the operating current of all motors decreases synchronously and continuously while maintaining a constant flight altitude, it is determined that the composite vortex field has provided stable external lift.

[0031] When both the low-frequency resonance state and the continuous decrease in the motor operating current are met simultaneously, an eddy current lockout confirmation signal is generated.

[0032] A further aspect of the present invention involves adjusting the output power of the rotor, including the following steps:

[0033] Reduce the average base speed of all rotors to the preset energy-saving level;

[0034] The gap between the total lift generated by the preset energy-saving level and the lift supporting the weight of the aircraft is compensated by the composite vortex field.

[0035] A further aspect of the present invention, in generating and executing energy-displacement flight commands, includes: continuously calculating and outputting fine-tuning commands for asymmetric thrust based on the changes in the low-frequency resonance state of the fuselage vibration spectrum and the fluctuations in the motor operating current.

[0036] Secondly, this invention provides an energy-saving route planning system for urban air traffic, employing the following technical solution:

[0037] An energy-saving route planning system for urban air traffic includes the following modules:

[0038] The airflow characteristic data packet generation module is used to collect Doppler frequency shift data and thermal infrared radiation data in front of the aircraft's flight path and generate airflow characteristic data packets.

[0039] The eddy target generation module can be used to parse airflow characteristic data packets, identify and lock specific natural airflows based on preset turbulence thresholds and preset energy thresholds, and generate usable eddy targets containing their three-dimensional coordinates and rotation directions.

[0040] The preset command generation module is used to receive the available vortex target, generate rotor control commands in reverse through the preset coupling control law based on its rotation direction parameters, and obtain the preset asymmetric thrust vector command.

[0041] The coupled vortex generation module is used to execute the preset command of the asymmetric thrust vector when the aircraft arrives at the coupling point calculated based on the location of the available vortex target, and to control the aircraft rotor system to generate and release the coupled vortex.

[0042] The eddy current lock signal generation module is used to monitor the fuselage vibration spectrum and motor operating current in real time. When the coupled vortex and a specific natural airflow form a composite eddy current field, it captures characteristic changes to generate an eddy current lock confirmation signal.

[0043] The flight command execution module is used to respond to the eddy current lock confirmation signal, adjust the rotor output power, and generate and execute energy replacement flight commands based on the feedback of the fuselage vibration spectrum and motor operating current.

[0044] In summary, the present invention has the following beneficial technical effects:

[0045] 1. By actively detecting, identifying, and utilizing micro-scale eddies in the urban environment, the system can actively extract energy from the environment to supplement the aircraft's power. This changes the traditional flight control model of simply consuming energy to combat environmental disturbances, enabling the aircraft to transform local airflows, which were originally considered negative impacts, into beneficial auxiliary power sources. This reduces the overall output power of the motor system while maintaining flight status, thereby extending the aircraft's range and operating time.

[0046] 2. By actively creating a combination of reverse-coupled vortices and natural vortices, a more stable composite vortex field is formed. The aircraft can lock into this composite field. The locked state reduces the direct impact of high-frequency chaotic micro-airflows on the fuselage, allowing the aircraft to shift from dealing with disordered disturbances to resonating with a relatively stable system, thereby reducing the high-frequency vibration of the fuselage and improving flight smoothness.

[0047] 3. With the help of microscale detection technology, the aircraft can detect and assess the available eddies at a very close distance ahead of its flight path and complete the entire process from decision-making to execution. This allows the aircraft to flexibly utilize local airflow phenomena generated by buildings for energy saving, improving the flexibility of energy utilization and making it suitable for complex low-altitude urban scenarios.

[0048] 4. By monitoring internal state parameters such as fuselage vibration and motor current in real time to confirm the coupling effect, the system can autonomously determine whether the energy exchange is successful and continuously optimize the coupling state. It can intelligently search for and utilize energy-saving opportunities during flight without human intervention, thereby improving the autonomous operation level and environmental adaptability of the aircraft. Attached Figure Description

[0049] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. The drawings are used to provide a further understanding of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0050] Figure 1 A flowchart illustrating an embodiment of this application is disclosed.

[0051] Figure 2 Structural schematic diagrams of embodiments of this application are disclosed. Detailed Implementation

[0052] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. All other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0053] The following is in conjunction with the appendix Figure 1 - Figure 2 A preferred description of the present invention is provided below.

[0054] See attached document Figure 1 This invention proposes an energy-saving route planning method for urban air traffic, comprising the following steps:

[0055] S1. Collect Doppler frequency shift data and thermal infrared radiation data in front of the aircraft's flight path to generate airflow characteristic data packets;

[0056] S2. Analyze the airflow characteristic data package, identify and lock specific natural airflows based on preset turbulence thresholds and preset energy thresholds, and generate usable vortex targets containing their three-dimensional coordinates and rotation direction.

[0057] S3. Receive the available vortex target, and based on its rotation direction parameters, generate rotor control commands in reverse through a preset coupling control law to obtain a preset command for asymmetric thrust vector.

[0058] S4. When the aircraft arrives at the coupling point calculated based on the location of the available vortex target, execute the preset command for the asymmetric thrust vector to control the aircraft rotor system to generate and release the coupling vortex.

[0059] S5. Real-time monitoring of fuselage vibration spectrum and motor operating current; when coupled vortex and specific natural airflow form a composite vortex field, capture characteristic changes to generate vortex lock confirmation signal.

[0060] S6. In response to the eddy current lock confirmation signal, adjust the rotor output power and generate and execute energy replacement flight commands based on the feedback of the fuselage vibration spectrum and motor operating current.

[0061] In one embodiment of the present invention, generating an airflow characteristic data package includes the following steps:

[0062] The airborne high-frequency miniature Doppler photoradar is activated to scan the target airspace, acquire the Doppler frequency shift data of the returned laser signal, and analyze the dynamic morphology information accordingly; the thermal infrared sensor array is activated to simultaneously measure the temperature difference between the target airspace and the surrounding environment, and quantify and generate energy intensity information; the dynamic morphology information and energy intensity information are spatiotemporally aligned to generate airflow characteristic data packets.

[0063] Specifically, when the urban aircraft is flying along its predetermined route, it activates its onboard composite detector to continuously scan the airspace directly in front of the aircraft, typically within a range of 5 to 30 meters; the two core sensing units of the composite detector are activated:

[0064] A high-frequency miniature Doppler photoradar unit emits a high-frequency laser beam into the target airspace. When the laser encounters suspended particles such as dust or water vapor moving in the air and is reflected back, its frequency changes due to the Doppler effect. The radar receiver captures these frequency changes of the returned laser signal, forming Doppler frequency shift data. By analyzing the spatial distribution patterns of this data, the motion state of the micro-airflow within the target airspace can be determined. For example, if the Doppler frequency shift data in a certain area shows a systematic distribution of positive and negative gradients, it indicates the presence of rotating airflow, and its rotation direction can be determined accordingly. The dispersion or fluctuation range of the frequency shift data directly reflects the degree of turbulence in the airflow, i.e., the intensity of turbulence. This resolved airflow motion information is integrated into dynamic morphological information.

[0065] Simultaneously, the thermal infrared sensing array unit is also activated. This array synchronously performs thermal imaging temperature measurement on the same target airspace scanned by the high-frequency miniature Doppler photoradar, and simultaneously collects the temperature of the stable ambient air around the aircraft as a reference. By calculating the difference between the target airspace temperature and the surrounding ambient temperature, the level of additional thermal energy contained in the airflow within that airspace can be quantified. The larger this temperature difference, the higher the potential energy of the airflow. The quantification results are integrated into energy intensity information.

[0066] Finally, the system performs spatiotemporal alignment processing on the acquired dynamic morphology information and energy intensity information. That is, for each spatial coordinate point or small spatial region, data on rotation direction, turbulence intensity, and thermal energy level collected at the same time are matched. In this way, two different types of data are fused into a unified data structure, forming a comprehensive dataset that describes both the physical morphology of the airflow and its energy state. This dataset is called the airflow characteristic data package. The airflow characteristic data package is used to comprehensively describe the state of the airflow ahead of the flight path. Its data structure is a set of data points, each including three-dimensional spatial coordinates, a collection timestamp, a vector representing the rotation direction, a floating-point number representing the turbulence intensity, and a level or value representing the energy intensity.

[0067] It should be noted that the composite detector is a combined sensor system integrated on the aircraft, used to simultaneously collect data from different physical dimensions. This system includes at least a high-frequency miniature Doppler lidar and a thermal infrared sensor array. The high-frequency miniature Doppler lidar is a radar device that uses the Doppler effect to remotely measure target velocity; here, it specifically refers to a lidar with a high operating frequency, small size, and suitability for airborne platforms. Its detection range is set to 5 to 30 meters according to actual needs. This setting is based on the common flight speeds and reaction times of urban low-altitude aircraft, ensuring sufficient time for decision-making and maneuvering. Dynamic morphology information is structured information obtained from Doppler frequency shift data analysis, specifically describing the macroscopic motion characteristics of airflow, such as the rotation direction of vortices and the overall stability. The thermal infrared sensor array is a detector composed of multiple infrared sensors arranged in a row, capable of simultaneously imaging a specific area to obtain its temperature distribution. Energy intensity information is structured information converted from thermal infrared radiation data, used to quantify the level of thermal energy contained within the airflow, usually expressed as the temperature difference or energy level with the environment.

[0068] The acquired Doppler frequency shift data records the change in the frequency of the laser signal reflected from the target space relative to the emission frequency. The data format is a mapping table of spatial coordinates and frequency shift values. The acquired thermal infrared radiation data records the raw data of the intensity of infrared radiation emitted by the object itself in the target space. After calibration and conversion, a temperature distribution map can be obtained.

[0069] For example, suppose an urban aircraft is cruising at an altitude of 50 meters above the ground. Its composite detector scans a range of 5 to 30 meters ahead. If, at approximately 20 meters ahead, the Doppler frequency shift data collected by the high-frequency miniature Doppler photoradar shows that within a spherical region with a radius of 1.5 meters centered at coordinates (20, 5, 52), the frequency shift value is -5 kHz on the left half and +5 kHz on the right half, with a relatively small overall data distribution variance, the system can deduce the presence of a stable counter-clockwise rotating airflow in this region, thus forming dynamic morphology information. Simultaneously, assuming the thermal infrared sensor array measures an average temperature of 28 degrees Celsius for this spherical region, while the surrounding ambient temperature is 25 degrees Celsius (a temperature difference of +3 degrees Celsius), the system can quantify and generate energy intensity information based on this.

[0070] Finally, the system integrates this information from the example to generate an airflow characteristic data package, which contains a record indicating that at coordinates (20,5,52), there is an airflow with a counterclockwise rotation direction, low turbulence intensity, and medium energy intensity level.

[0071] In one embodiment of the present invention, generating a usable eddy current target includes the following steps:

[0072] Receive airflow characteristic data packets and calculate the distribution variance of Doppler frequency shift data; compare the distribution variance with a preset turbulence threshold to determine the stability of the airflow structure; compare the temperature difference calculated from thermal infrared radiation data with a preset energy threshold to determine the energy value of the airflow; lock specific natural airflows that simultaneously meet the determination of structural stability and energy value, extract their three-dimensional coordinates and rotation direction parameters, and generate usable vortex targets.

[0073] Specifically, the data package containing both airflow structure and energy attributes is analyzed to filter out specific natural airflows with utilization value from continuous airflow information; the analysis process includes:

[0074] The system applies airflow stability screening rules to examine the dynamic morphology information associated with each data point in the airflow characteristic data package, particularly the Doppler frequency shift data. It calculates the variance of the Doppler frequency shift data distribution within each small spatial domain. This variance quantifies the internal velocity consistency of the airflow; a small variance indicates uniform flow and structural stability, while a large variance indicates turbulent airflow, i.e., high turbulence intensity. The system compares the calculated variance with a pre-set turbulence threshold. Only when the variance is below this threshold is the corresponding airflow preliminarily determined to be structurally stable and allowed to proceed to the next round of screening.

[0075] The system applies energy utilization screening rules to check the energy intensity information of all airflows that have passed the stability screening, i.e., the temperature difference shown in the thermal infrared data. This temperature difference value is compared with a pre-set energy threshold. Only when the temperature difference is higher than the energy threshold is the system determined that the airflow contains sufficient thermal energy to be utilized by the aircraft.

[0076] Based on preset energy level thresholds, the energy intensity of the airflow is divided into multiple levels, for example:

[0077] Low energy level: when ΔT <T low If the energy intensity is insufficient, it will not be utilized.

[0078] Medium energy level: when T low ≤ΔT <T high At that time, it was determined to be of medium energy intensity;

[0079] High energy level: when ΔT ≥ T high At that time, it was determined to be of high energy intensity.

[0080] Among them, T low The minimum energy threshold is set to ensure that the energy gain provided by the selected airflow can cover the additional energy consumption caused by the aircraft's coupling operation; T high The high energy threshold is set based on a comprehensive consideration of the aircraft's structural strength and safe operating boundaries, avoiding entrainment in excessively high-energy turbulence. This energy level is used to quantify the potential energy value of the airflow when generating usable vortex targets, and to calculate the rotor speed difference in subsequent coupled control laws. Provide parameter basis.

[0081] Natural airflows must simultaneously meet the two screening rules mentioned above—both structurally stable and energy-rich—before being ultimately identified as a target by the system. Once identified, the system locks onto the target and extracts its key parameters from the airflow characteristic data package, including the three-dimensional coordinates identifying its center point, vector data characterizing its rotation direction, and energy level quantifying its energy level.

[0082] Finally, the system encapsulates these extracted parameters into standardized data objects, generates usable eddy current targets, and passes them to the subsequent control decision module.

[0083] Variance calculation formula:

[0084]

[0085] in, The variance of the distribution of Doppler frequency shift data directly reflects the intensity of turbulence, and its unit is the square of the frequency, such as the square of Hertz. This indicates the number of samples collected within the target airspace. The value of each Doppler frequency shift data point is expressed in Hertz. For all The arithmetic mean of the frequency shift data points is expressed in Hertz. This represents the total number of data points collected within the current target airspace, a dimensionless count value. This is calculated... The value can quantify the stability of the airflow, providing a basis for subsequent comparison with the turbulence threshold.

[0086] Among them, the vortex target can be used as a structured data unit to indicate a clear energy-saving opportunity to the flight control system. The data structure of the data unit includes three-dimensional coordinates for accurately locating the position of the vortex in space; rotation direction parameters, usually three-dimensional vectors, for describing the rotation axis and direction of the vortex; and energy level for indicating how much energy the vortex can provide.

[0087] The airflow stability screening rule is a logical judgment instruction built into the parsing program. The core of this instruction is to compare the variance of the Doppler frequency shift data distribution of the airflow with the turbulence threshold to determine whether its structure is stable.

[0088] It should be noted that the turbulence threshold is a preset value used to distinguish between stable and turbulent airflow. Its setting is based on statistical results derived from field measurements and simulation analyses of urban canyon wind fields under n different weather conditions. This threshold ensures that only airflows with clear morphology and low dissipation are selected. The energy utilization screening rule is another logical judgment instruction. Its core is to compare the thermal infrared temperature difference of the airflow with the energy threshold to determine whether it has energy utilization value. Similarly, the energy threshold is a preset temperature difference value, for example, set to 1.5 degrees Celsius. Its setting is based on comprehensively considering the aircraft's energy consumption model and aerodynamic efficiency, ensuring that the energy gain provided by the selected airflow can offset the additional consumption caused by the aircraft's coupling operations.

[0089] For example, further illustrating with the aforementioned example, when analyzing the airflow characteristic data packet at coordinates (20, 5, 52), the system first applies an airflow stability screening rule, which calculates the variance of the Doppler frequency shift data in that region, for example, 0.8 kHz squared. Assuming a preset turbulence threshold of 1.5 kHz squared, since 0.8 is less than 1.5, the airflow is determined to be structurally stable. Next, the system applies an energy utilization screening rule, reading its energy intensity information as a temperature difference of +3 degrees Celsius. Assuming a preset energy threshold of 1.5 degrees Celsius, since 3.0 is greater than 1.5, the airflow is determined to be usable. Because the airflow satisfies both rules, the system ultimately locks it in, extracts its parameters, and encapsulates them to generate a usable vortex target. An example of its content is: three-dimensional coordinates (20, 5, 52), rotation direction counterclockwise, and energy level high.

[0090] In one embodiment of the present invention, the coupling control law is derived in reverse from the input natural eddy rotation direction to generate a rotor control command that can generate a reverse rotation torque.

[0091] Specifically, when the flight control system receives a generated exploitable vortex target indicating a specific energy-saving opportunity, it first reads the rotation direction parameters within the exploitable vortex target data unit. Based on the core principle of reverse coupling, the system needs to instruct the aircraft to actively generate a vortex with a rotation direction opposite to this natural airflow, in order to achieve energy engagement in subsequent stages. To this end, the system invokes a preset coupling control law. The function of the coupling control law is to derive, based on the input natural vortex rotation direction, a rotor control command that generates a reverse rotational torque. For example, if the rotation direction parameter of the exploitable vortex target is identified as counterclockwise, the coupling control law will automatically generate an execution plan aimed at causing the aircraft to generate a clockwise rotational effect. A specific example of this plan is: instructing the rotor assembly on the clockwise rotation side of the aircraft to moderately increase its speed, while simultaneously instructing the rotor assembly on the counterclockwise side to correspondingly decrease its speed, thereby creating a clear thrust difference.

[0092] This series of generated commands, including the precise speed difference between the two rotor combinations, the duration for which the asymmetric thrust needs to be maintained, and the specific triggering time for the command, are packaged together into a structured data file. This file is the preset command for the asymmetric thrust vector, which will be sent to the flight execution module to await activation.

[0093] The formula for calculating the rotor speed difference is:

[0094]

[0095] in, This represents the target speed difference that the combination of the two rotors on both sides of the aircraft needs to produce, measured in revolutions per minute. It is a dimensionless control gain coefficient used to adjust the intensity of the artificial vortex. Its setting is based on the optimal coupling efficiency point calibrated in the wind tunnel experiment, and its value is usually between 0.5 and 1.5. This is a direction factor, taking a value of +1 or -1, used to achieve reverse control. If the eddy current target can be used to rotate counter-clockwise... If the value is +1, the aircraft is instructed to generate a clockwise torque; otherwise, -1 is taken. This is a function representing the base rotational speed adjustment calculated based on the energy level of the available vortex target, measured in revolutions per minute (rpm). Higher energy levels result in larger function outputs, meaning a stronger reverse vortex needs to be generated. In this embodiment... It can be a piecewise linear function or a lookup table function, for example, when the energy level is determined to be medium. The value can be set to 150 revolutions per minute; when the energy level is determined to be high. The value can be set to 300 revolutions per minute, thereby achieving a clear mapping between energy level and specific control quantity.

[0096] Among them, the asymmetric thrust vector preset command is a detailed set of commands to be executed, which is used to provide precise control parameters for the subsequent vortex coupling maneuver. Its data structure contains three core fields: the speed difference value that specifies the difference in speed between the two rotors, the duration that the difference should be maintained, and the triggering time that determines when to start executing the command.

[0097] Rotor control commands are specific command flows generated by coupled control laws, which directly act on the aircraft's motor controllers to change the rotational speed of each rotor. Coupled control laws are algorithms or function libraries pre-installed in the flight control system. They encapsulate aerodynamic models and can inversely calculate the optimal rotor control strategy based on external airflow characteristics. Their design goal is to create artificial vortices with shapes and strengths best suited for coupling with natural vortices.

[0098] For example, suppose the flight control system receives a usable vortex target with three-dimensional coordinates (20, 5, 52), a counter-clockwise rotation direction, and a high energy level, as shown in the example above. The system reads that the rotation direction is counter-clockwise, then invokes the coupling control law to create a counter-clockwise vortex, generating a rotor control command that instructs the right rotor assembly to rotate at a speed higher than the left rotor assembly by a specific value. Assuming that the determined speed difference is 300 revolutions per minute based on the high energy level and the control law calculation, the estimated duration of the coupling action is 1.2 seconds, and the optimal trigger time calculated based on the aircraft's current speed is 2.5 seconds, the system packages these parameters and finally generates a preset asymmetric thrust vector command, which can be expressed as: speed difference 300 revolutions per minute, duration 1.2 seconds, trigger time 2.5 seconds.

[0099] In one embodiment of the present invention, calculating the coupling point in step S4 includes the following steps:

[0100] Receive the current speed and position of the aircraft; combine the three-dimensional coordinates of the available vortex target with the preset vortex formation time to calculate and generate the coupling point.

[0101] The formation of a coupled vortex involves: instructing the rotor assembly on one side of the aircraft to increase its rotational speed, while simultaneously instructing the rotor assembly on the other side to decrease its rotational speed, generating an asymmetric downwash airflow; and utilizing this asymmetric downwash airflow to curl beneath the aircraft and form a coupled vortex.

[0102] Specifically, after receiving the preset command for the asymmetric thrust vector, the flight execution module enters a standby state and begins executing the positioning execution timing. By continuously acquiring the real-time status of the aircraft, including its current three-dimensional spatial position and flight velocity vector, and combining this with the target vortex position information contained in the preset command for the asymmetric thrust vector, the system performs forward path calculation to determine the optimal position for executing the asymmetric thrust. This optimal position is the coupling point. This coupling point is typically set at a specific distance directly in front of the usable vortex target to ensure that the artificial vortex generated by the aircraft has sufficient time and space to form and achieves a good coupling pattern when the aircraft arrives at the natural vortex.

[0103] When the aircraft's navigation system confirms that it is about to reach the pre-calculated coupling point, the entire scheme is activated. At the moment of arrival at the coupling point, the flight control system strictly issues commands to the distributed rotor system according to the rotor control commands packaged in the asymmetric thrust vector preset commands. This set of commands will instantaneously change the power output of the rotor combination on both sides of the aircraft. For example, the speed of the right rotor is increased, while the speed of the left rotor is decreased, thereby generating a strong, uneven downwash. Due to the uneven force, this asymmetric downwash will naturally curl and rotate after leaving the rotor disk, rapidly forming a vortex directly below the aircraft with a rotation direction opposite to the target natural airflow, and with its shape and intensity under the control of the preset commands. This actively generated artificial vortex is the coupled vortex.

[0104] The kinematic formula for calculating the coupling point is as follows:

[0105]

[0106] in, The three-dimensional spatial coordinate vector representing the coupling point, in meters. The three-dimensional spatial coordinate vector representing the center of the exploitable eddy target, in meters, is obtained from the exploitable eddy target. This represents the aircraft's current velocity vector, measured in meters per second. This is a preset vortex formation time constant, measured in seconds, representing the time required from the application of asymmetric thrust to the formation of the coupled vortex. Using this formula, coupled vortices can be generated in advance, before the aircraft reaches the precise location of the natural vortex, achieving timing matching.

[0107] The coupled vortex is a rotating airflow artificially created below the aircraft by actively controlling the rotor thrust. Its rotation direction is controlled and designed to be opposite to the rotation direction of the natural airflow it will encounter, serving as a medium for energy exchange with the natural vortex. The coupling point is a precisely calculated three-dimensional coordinate located in front of the target vortex along the flight path. The optimal spatiotemporal node for triggering the preset command for the asymmetric thrust vector ensures that the coupled vortex is generated at the most effective location and time. A distributed rotor system refers to multiple independently or grouped rotor power units mounted on the aircraft. Its characteristic is the ability to achieve refined, asymmetric control of the aircraft's attitude and thrust vector through differentiated power output.

[0108] The preset vortex formation time is the brief physical process required for the downwash airflow to generate, curl, and form a coupled vortex with a stable structure and sufficient strength to interact with natural vortices when the aircraft changes its rotor speed through asymmetric thrust. This time is the vortex formation time. This is typically similar to the formation time of vortex rings in fluid mechanics. The expected size of the vortex is related to the rotor diameter, thrust difference, and air viscosity, and can be initially estimated through computational fluid dynamics simulations or semi-empirical formulas; for example, a simplified semi-empirical estimation model can be expressed as: =c*d / Δv, where d is the characteristic diameter of the aircraft rotor system, for example, the diagonal rotor spacing; Δv is the difference in downwash velocity generated by the combination of the two rotors when performing asymmetric thrust; and c is a dimensionless constant calibrated through wind tunnel experiments or simulations, typically between 2.0 and 3.5, for example, c can be taken as 2.5 in this embodiment. The preset vortex formation time also includes sensor and actuator delays. From the issuance of control commands to the change of motor speed and then to the stabilization of the airflow field, the entire closed-loop system has an inherent response delay. This delay includes: the time required to process sensor data and run the control algorithm; the time for the command to be transmitted between the flight control computer and the ESC; and the electromechanical response time of the motor and propeller from receiving the new command to reaching the target speed. The value of must be greater than or equal to the total system delay time; otherwise, the coupled vortex will not be effectively formed when the command is triggered. This minimum time window is usually determined by measuring the system's step response.

[0109] For example, suppose an aircraft flies at a speed of 10 meters per second toward a usable vortex target at coordinates (20, 5, 52), and receives a preset command for an asymmetric thrust vector with a rotational speed difference of 300 revolutions per minute, a duration of 1.2 seconds, and a trigger timing of 2.5 seconds. Assuming the preset vortex formation time is 0.5 seconds, the system calculates that the coupling point should be 5 meters in front of the target, i.e., (15, 5, 52). When the aircraft reaches this coupling point, the system executes the preset command, instructing the right rotor assembly to rapidly increase its rotational speed and the left rotor assembly to rapidly decrease its rotational speed, with the difference reaching 300 revolutions per minute and maintained for 1.2 seconds. This creates a clockwise rotating asymmetric downwash airflow below the aircraft, which quickly forms a relatively stable clockwise coupled vortex, ready to interact with the counterclockwise rotating natural airflow in front.

[0110] In one embodiment of the present invention, generating an eddy current locking confirmation signal includes the following steps:

[0111] The fuselage vibration spectrum is continuously monitored using a fuselage vibration sensor. When the spectrum changes from a high-frequency state to a low-frequency state, coupling is determined to have formed. The operating current of each rotor motor is monitored simultaneously. When the operating current of all motors decreases synchronously while maintaining a constant flight altitude, it is determined that the composite eddy current field has provided stable external lift. When both the low-frequency resonance state and the continuous decrease in motor operating current are met, an eddy current lock-in confirmation signal is generated.

[0112] Specifically, after the aircraft successfully creates and releases the coupled vortex at the coupling point, the system enters the real-time monitoring and status confirmation phase to determine whether the artificial coupled vortex has successfully interacted with the target natural airflow and formed a stable and usable composite vortex field; by simultaneously activating two different sensors, characteristic signals of successful coupling are captured.

[0113] Multiple vibration sensors deployed within the fuselage continuously collect spectral data of the aircraft's structural vibrations. During normal flight or before vortex coupling forms, fuselage vibrations typically manifest as high-frequency, irregular, and chaotic vibrations caused by multi-rotor airflow disturbances. However, when artificially created coupled vortices successfully engage with natural airflow, forming a composite vortex field that envelops the aircraft, the aircraft resonates with this composite vortex field. This resonance phenomenon causes a significant change in the fuselage's vibration spectrum, transforming it from a high-frequency chaotic state to a low-frequency resonant state with one or more distinct peaks. Once this characteristic spectral shift is detected, the system determines that coupling has initially formed.

[0114] The system acquires operating current data by monitoring the drive circuits of each rotor motor in real time. During normal hovering or cruise, all motors need to output sufficient power to generate lift to support the aircraft's weight, maintaining a relatively high baseline operating current. When a composite eddy current field forms and stabilizes on the aircraft, this external eddy current field provides additional lift. Typically, to maintain the original flight altitude, the flight control system automatically reduces the rotational speed of all rotors, causing a synchronized and continuous decrease in the operating current of all motors. The system uses this phenomenon as confirmation that the composite eddy current field has provided stable external lift. Ultimately, only when both the low-frequency resonance characteristics of the vibration spectrum and the continuous decrease in the operating current of all motors are simultaneously confirmed by the system will a final determination be made, confirming that the aircraft has entered a stable eddy current lock-in state. At this point, the system immediately generates and broadcasts an eddy current lock-in confirmation signal to the flight control core module.

[0115] Among them, the eddy lock confirmation signal is a Boolean or event-type signal generated by the monitoring system, which is used to clearly announce to the flight control system that the aircraft has successfully utilized external airflow and entered a stable state that can save energy.

[0116] The fuselage vibration spectrum is a data graph describing the amplitude distribution of an aircraft structure's vibration at different frequencies. By analyzing the peak positions and shapes in the spectrum, the vibration modes and sources of the aircraft can be determined. Low-frequency resonance refers to the concentration of the main energy of the aircraft structure's vibration at a few lower frequency points, a typical characteristic of coupling between the aircraft and a large, stable external airflow field. Motor operating current is the current flowing through the electric motor that drives the rotor; its magnitude directly reflects the magnitude of the motor's output torque and the aircraft's instantaneous power consumption. A composite vortex field is a new, larger-scale stable rotating airflow structure formed by the interaction and merging of coupled vortices actively generated by the aircraft with natural airflow in the environment.

[0117] For example, after the aircraft releases a clockwise coupled vortex at coordinates (15, 5, 52), data from the fuselage vibration sensors shows that, assuming the initial chaotic vibration spectrum was distributed between 50 and 100 Hz, it rapidly transitions to a low-frequency resonant state with a predominantly 25 Hz peak after approximately 0.8 seconds. Simultaneously, the system monitors the operating current of the eight rotor motors, which, while maintaining a constant flight altitude, synchronously decreases from a stable 15 amps to 11 amps and remains stable at this level. Because both the vibration spectrum shift and the motor current decrease are simultaneously satisfied, the system determines that it has successfully entered an eddy current lock state. It then immediately generates a true eddy current lock confirmation signal and sends it to the flight control system, preparing to switch flight modes.

[0118] In one embodiment of the present invention, adjusting the output power of the rotor includes the following steps:

[0119] The average base speed of all rotors is reduced to a preset energy-saving level; the gap between the total lift generated by the preset energy-saving level and the lift supporting the weight of the aircraft is compensated by the composite vortex field.

[0120] Specifically, when the front-end processor of the flight control system receives the eddy lock confirmation signal, it will immediately trigger the flight mode switch. The control logic will switch from the conventional flight mode, which prioritizes maintaining absolute altitude and attitude, to the energy exchange mode, which prioritizes maximizing the use of external energy and minimizing its own energy consumption.

[0121] Upon entering this mode, the primary action is to reduce the average base output power of all rotors. Specifically, the flight control system sends commands to the motor controllers of all distributed rotors, lowering their average base speed to a preset energy-saving level. This energy-saving level is based on the premise that the total lift generated is theoretically insufficient to independently support the entire weight of the aircraft; the missing lift will be compensated by the already formed composite vortex field. This operation directly transforms the aircraft from a state of hovering under its own power to an energy-displacement flight state that works in conjunction with the external airflow, thereby reducing energy consumption.

[0122] After the base power is reduced, the aircraft does not remain stationary but requires precise control to maintain a stable coupling with the natural vortex. The system continuously uses two feedback signals—the fuselage vibration spectrum and the motor operating current—for closed-loop fine-tuning. If a weakening trend in coupling is detected, such as a decrease in the low-frequency resonance peak or a sign of a rebound in the motor current, the system will continuously and slightly adjust the speed difference between the two rotor combinations, i.e., fine-tune the asymmetric thrust, with the goal of minimizing its own energy consumption. This fine-tuning aims to strengthen or stabilize the artificial coupled vortex, ensuring that its meshing with the natural vortex is always at its optimal state. This series of continuously generated and dynamically adjusted control commands, aimed at maintaining stable coupling, is the energy-displacement flight command. It will be executed cyclically until the composite vortex field disappears or the aircraft needs to break away from the current vortex.

[0123] The calculation formula for setting the speed fine-tuning amount is as follows:

[0124]

[0125] in, Is The amount of fine-tuning required for asymmetric thrust at all times, measured in revolutions per minute. yes The feedback error at any given time can be defined as the difference between the target current value and the actual monitored motor operating current, measured in amperes. , , These are the gain coefficients of the proportional, integral, and derivative controllers, all of which are dimensionless constants. Their values ​​were obtained by tuning and optimizing over 1000 eddy current coupling processes of different intensities in a simulation environment to ensure the speed and stability of the control response. The differential term of the error represents the rate of change of the error; The integral term of the error represents the cumulative historical error; the application of this formula enables the aircraft to automatically and accurately maintain the optimal energy replacement state.

[0126] The energy-displacement flight command is a dynamically generated control command used for fine-tuning rotor output. Its goal is to maintain a stable coupling state between the aircraft and the external vortex while consuming minimal of its own energy. In energy-displacement mode, the aircraft's flight control logic shifts from the conventional attitude stabilization mode to an energy-optimal management mode, prioritizing the use of external environmental energy to assist flight. The energy-saving level is a preset rotor base speed value. The lift generated by this value is precisely calculated and falls between the hovering lift without external assistance and the minimum lift required after utilizing the vortex. This is the basic parameter for activating the energy-displacement mode.

[0127] For example, upon receiving a true eddy lock confirmation signal, the flight control system promptly switches from the normal flight mode to the energy replacement mode. The following example uses hypothetical data: The system first executes a command to reduce the average base speed of all rotors from the original 1800 rpm to an energy-saving level of 1400 rpm. After the speed reduction, the system continuously monitors and finds the average motor current stable at 11 amps. After approximately 15 seconds of flight, if the system detects a slight upward trend in the average motor current towards 11.5 amps, while the amplitude of the 25 Hz resonance peak in the vibration spectrum decreases by 5%, the control system determines that the coupling state has slightly weakened and immediately generates an energy replacement flight command, calculating the need for a fine-tuning of increasing the right rotor speed by 20 rpm and decreasing the left rotor speed by 20 rpm. After executing this command, the average motor current quickly drops back to 11 amps, the resonance peak intensity recovers, and the stable coupling between the aircraft and the eddy current is maintained, thus continuously achieving energy-saving flight.

[0128] See appendix Figure 2 The present invention also proposes an energy-saving route planning system for urban air traffic, comprising the following modules:

[0129] The airflow characteristic data packet generation module is used to collect Doppler frequency shift data and thermal infrared radiation data in front of the aircraft's flight path and generate airflow characteristic data packets.

[0130] The eddy target generation module can be used to parse airflow characteristic data packets, identify and lock specific natural airflows based on preset turbulence thresholds and preset energy thresholds, and generate usable eddy targets containing their three-dimensional coordinates and rotation directions.

[0131] The preset command generation module is used to receive the available vortex target, generate rotor control commands in reverse through the preset coupling control law based on its rotation direction parameters, and obtain the preset asymmetric thrust vector command.

[0132] The coupled vortex generation module is used to execute the preset command of the asymmetric thrust vector when the aircraft arrives at the coupling point calculated based on the location of the available vortex target, and to control the aircraft rotor system to generate and release the coupled vortex.

[0133] The eddy current lock signal generation module is used to monitor the fuselage vibration spectrum and motor operating current in real time. When the coupled vortex and a specific natural airflow form a composite eddy current field, it captures characteristic changes to generate an eddy current lock confirmation signal.

[0134] The flight command execution module is used to respond to the eddy current lock confirmation signal, adjust the rotor output power, and generate and execute energy replacement flight commands based on the feedback of the fuselage vibration spectrum and motor operating current.

[0135] Each of the modules can be implemented in whole or in part through software, hardware, or a combination thereof. It supports hardware embedded in or independent of the processor in the computer device, and also supports software stored in the memory of the computer device, so that the processor can call and execute the operations corresponding to each of the above modules.

[0136] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be included within the protection scope of the present invention.

Claims

1. A method for energy-saving route planning in urban air traffic, characterized in that, Includes the following steps: S1. Collect Doppler frequency shift data and thermal infrared radiation data in front of the aircraft's flight path to generate airflow characteristic data packets; S2. Analyze the airflow characteristic data package, identify and lock specific natural airflows based on preset turbulence thresholds and preset energy thresholds, and generate usable vortex targets containing their three-dimensional coordinates and rotation direction. S3. Receive the available vortex target, and based on its rotation direction parameters, generate rotor control commands in reverse through a preset coupling control law to obtain a preset command for asymmetric thrust vector. S4. When the aircraft arrives at the coupling point calculated based on the location of the available vortex target, execute the preset command for the asymmetric thrust vector to control the aircraft rotor system to generate and release the coupling vortex. S5. Real-time monitoring of fuselage vibration spectrum and motor operating current; when coupled vortex and specific natural airflow form a composite vortex field, capture characteristic changes to generate vortex lock confirmation signal. S6. In response to the eddy current lock confirmation signal, adjust the rotor output power and generate and execute energy replacement flight commands based on the feedback of the fuselage vibration spectrum and motor operating current.

2. The urban air traffic energy-saving route planning method according to claim 1, characterized in that, Generating an airflow characteristic data package includes the following steps: The airborne high-frequency miniature Doppler photoradar is activated to scan the target airspace, acquire the Doppler frequency shift data of the returned laser signal, and analyze the dynamic morphology information accordingly. The thermal infrared sensor array is activated to simultaneously measure the temperature difference between the target airspace and the surrounding environment, and energy intensity information is quantified and generated. The dynamic morphology information and energy intensity information are spatiotemporally aligned to generate airflow characteristic data packages.

3. The urban air traffic energy-saving route planning method according to claim 1, characterized in that, Generating exploitable eddy current targets includes the following steps: Receive airflow characteristic data packets and calculate the distribution variance of Doppler frequency shift data; The distribution variance is compared with a preset turbulence threshold to determine the stability of the airflow structure; The temperature difference calculated from thermal infrared radiation data is compared with a preset energy threshold to determine the value of airflow energy. By locking onto a specific natural airflow that simultaneously satisfies both structural stability and energy value criteria, its three-dimensional coordinates and rotation direction parameters are extracted to generate a usable vortex target.

4. The urban air traffic energy-saving route planning method according to claim 1, characterized in that, The coupling control law is based on the natural vortex rotation direction of the input, and the rotor control command that can generate a reverse rotation torque is derived in reverse.

5. The urban air traffic energy-saving route planning method according to claim 1, characterized in that, Calculating the coupling point includes the following steps: Receive the aircraft's current speed and position; The coupling point is calculated by combining the three-dimensional coordinates of the available vortex target with the preset vortex formation time.

6. The urban air traffic energy-saving route planning method according to claim 1, characterized in that, The formation of coupled vortices includes the following steps: The rotor assembly on one side of the aircraft is commanded to increase its rotational speed, while the rotor assembly on the other side is commanded to decrease its rotational speed, thereby generating an asymmetric downwash airflow. The asymmetric downwash airflow is used to form coupled vortices by curling beneath the aircraft.

7. The urban air traffic energy-saving route planning method according to claim 1, characterized in that, Generating an eddy current lock confirmation signal includes the following steps: By continuously monitoring the vibration spectrum of the fuselage using fuselage vibration sensors, coupling is determined to occur when the spectrum changes from a high-frequency state to a low-frequency state. The operating current of each rotor motor is monitored synchronously. When the operating current of all motors decreases synchronously and continuously while maintaining a constant flight altitude, it is determined that the composite vortex field has provided stable external lift. When both the low-frequency resonance state and the continuous decrease in the motor operating current are met simultaneously, an eddy current lockout confirmation signal is generated.

8. The urban air traffic energy-saving route planning method according to claim 1, characterized in that, Adjusting the rotor's output power includes the following steps: Reduce the average base speed of all rotors to the preset energy-saving level; The gap between the total lift generated by the preset energy-saving level and the lift supporting the weight of the aircraft is compensated by the composite vortex field.

9. The urban air traffic energy-saving route planning method according to claim 1, characterized in that, The generation and execution of energy replacement flight commands also includes: continuously calculating and outputting fine-tuning commands for asymmetric thrust based on the changes in the low-frequency resonance state of the fuselage vibration spectrum and the fluctuations in the motor operating current.

10. An energy-saving route planning system for urban air traffic, characterized in that, Includes the following modules: The airflow characteristic data packet generation module is used to collect Doppler frequency shift data and thermal infrared radiation data in front of the aircraft's flight path and generate airflow characteristic data packets. The eddy target generation module can be used to parse airflow characteristic data packets, identify and lock specific natural airflows based on preset turbulence thresholds and preset energy thresholds, and generate usable eddy targets containing their three-dimensional coordinates and rotation directions. The preset command generation module is used to receive the available vortex target, generate rotor control commands in reverse through the preset coupling control law based on its rotation direction parameters, and obtain the preset asymmetric thrust vector command. The coupled vortex generation module is used to execute the preset command of the asymmetric thrust vector when the aircraft arrives at the coupling point calculated based on the location of the available vortex target, and to control the aircraft rotor system to generate and release the coupled vortex. The eddy current lock signal generation module is used to monitor the fuselage vibration spectrum and motor operating current in real time. When the coupled vortex and a specific natural airflow form a composite eddy current field, it captures characteristic changes to generate an eddy current lock confirmation signal. The flight command execution module is used to respond to the eddy current lock confirmation signal, adjust the rotor output power, and generate and execute energy replacement flight commands based on the feedback of the fuselage vibration spectrum and motor operating current.

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