A safety control method and system for a manned unmanned aerial vehicle with a backup thruster

Abstract

This application provides a safety control method and system for a manned unmanned aerial vehicle (UAV) with backup thrusters. The method involves online identification of the operating status parameters of the main propulsion system to obtain online diagnostic results for the UAV; removing faulty thrusters from the effective thruster set based on the online diagnostic results and determining an emergency response level matching the current fault state; activating and pre-starting independent backup thrusters in a low-power standby state, thereby incorporating them into the effective thruster set and determining the thrust distribution scheme for the effective thrusters in the UAV; and controlling the UAV to land safely according to the thrust distribution scheme and emergency response level, until the UAV lands, after which the landing buffer device is activated and the power supply to all effective thrusters is cut off. Based on this scheme, sufficient power and control margin can still be provided to ensure the safe landing of the UAV even when the redundancy of the main propulsion system is exhausted.

Description

Technical Field

[0001] This application relates to the field of flight safety control technology for manned unmanned aerial vehicles (UAVs), and more specifically, to a safety control method and system for a manned UAV with a backup thruster. Background Technology

[0002] As the core carrier for low-altitude manned transportation in the field of aviation equipment, the flight safety of manned drones is directly related to the lives of passengers and the integrity of equipment. Sudden failure of the main propulsion unit is the main cause of flight loss of control and crash accidents. The industry urgently needs efficient and reliable emergency safety control technology to ensure the stability, controllability and safe landing of manned drones in failure state.

[0003] Existing manned unmanned aerial vehicle (UAV) safety control technologies are mainly divided into three categories: passive fault-tolerant control, active fault-tolerant control, and hybrid fault-tolerant control. Passive fault-tolerant control relies on pre-defined hardware redundancy design and robust control algorithms, and can cope with a limited number of known fault modes without an online fault diagnosis module, but it lacks generalization ability for undefined multiple faults. Active fault-tolerant control dynamically reconstructs the controller or reallocates control commands after identifying fault characteristics in real time through a fault detection and diagnosis module. It has strong adaptability but high computational and modeling costs, and the contradiction between fault diagnosis accuracy and control reconstruction real-time performance has not been effectively resolved. Hybrid fault-tolerant control combines the above two mechanisms, striving to balance robustness. While these methods offer stability and adaptability, their highly complex system framework and frequent control strategy switching can disrupt stability conditions and trigger chattering. A common technical feature of these methods is that their fault tolerance relies entirely on the redundancy redundancy reconfiguration among the aircraft's existing thrusters—that is, when one thruster fails, compensation is achieved by adjusting the thrust distribution of the remaining healthy thrusters. However, in extreme scenarios where multiple thrusters fail successively or the fault location is unique, resulting in a severe shortage of remaining thrust and control torque, the system's internal redundancy resources are exhausted. Thrust redundancy alone cannot maintain the aircraft's attitude stability and controlled landing, posing a serious challenge to the flight safety of manned UAVs. Therefore, how to provide sufficient power and control margin to ensure the safe landing of manned UAVs even when the main propulsion system's redundancy is exhausted has become a major challenge for the industry. Summary of the Invention

[0004] This application provides a safety control method and system for a manned unmanned aerial vehicle (UAV) with a backup thruster, which can provide sufficient power and control margin to ensure the safe landing of the UAV even when the redundancy of the main propulsion system is exhausted.

[0005] In a first aspect, this application provides a safety control method for a manned unmanned aerial vehicle with a backup thruster, comprising the following steps: By using multi-sensor data fusion to perform residual evaluation on the operating status parameters of the main propulsion system, online diagnostic results for manned UAVs in terms of fault type and fault severity are obtained. Based on the online diagnostic results, the faulty thruster is removed from the set of effective thrusters, and an emergency response level matching the current fault state is selected from the multi-level protection measures through the mapping relationship between the remaining thrust margin and the preset safety threshold. The independent standby thrusters in low-power standby state are activated and pre-started, and then the independent standby thrusters are incorporated into the effective thruster set. The thrust distribution scheme of the effective thrusters in the manned UAV is obtained by augmenting and reconstructing the control allocation matrix. According to the thrust distribution scheme and the emergency response level, the manned UAV is controlled to land safely until the manned UAV lands, after which the landing buffer device is activated and the power supply of all effective thrusters is cut off.

[0006] In some embodiments, residual evaluation of the operating state parameters of the main propulsion system through multi-sensor data fusion is used to obtain online diagnostic results for the manned unmanned aerial vehicle in terms of fault type and fault severity. Specifically, this includes: For each active propulsion unit in a manned UAV, multi-modal operating status parameters are continuously collected by speed sensors, current sensors, temperature sensors, and body vibration sensors installed on the active propulsion unit to obtain the operating status data of the active propulsion unit; The expected rotational speed in the operating status data is compared with the measured rotational speed to obtain the normalized residual signal of the main propulsion thruster, and then the normalized residual signal of each main propulsion thruster in the manned UAV is obtained. Data feature fusion and fault mode matching are performed based on the normalized residual signals and operational status data of all active propulsion units to obtain online diagnostic results for manned UAVs in terms of fault type and fault severity.

[0007] In some embodiments, removing faulty thrusters from the set of effective thrusters based on the online diagnostic results, and selecting an emergency response level matching the current fault state from multi-level protection measures through the mapping relationship between remaining thrust margin and preset safety threshold, specifically includes: The faulty thruster was identified based on the online diagnostic results. The faulty thruster is removed from the set of effective thrusters and its thrust contribution is deducted from the total thrust of the UAV, thereby calculating the remaining thrust margin of the manned UAV. The remaining thrust margin is compared one by one with the three-level protection threshold preset in the flight controller to obtain the threshold range. Based on the threshold range, an emergency response level matching the current fault state is selected from multi-level protection measures.

[0008] In some embodiments, the fault types include inter-turn short circuits in motor windings, demagnetization of permanent magnets, wear of bearing inner rings, damage to blade structure, and no faults.

[0009] In some embodiments, incorporating the independent backup thrusters into the effective thruster set and obtaining the thrust allocation scheme for the effective thrusters in the manned UAV through augmented reconstruction of the control allocation matrix specifically includes: Once the thrust of the independent backup thruster reaches the minimum control speed, the independent backup thruster and the main power thruster determined to be fault-free in the online diagnostic results are merged into an effective thruster set; An augmented control effectiveness matrix is ​​constructed based on the aforementioned set of effective thrusters; The augmented control effectiveness matrix is ​​solved by weighted pseudo-inverse to obtain the thrust distribution scheme of the effective thrusters in the manned UAV.

[0010] In some embodiments, the independent backup thruster adopts a ducted fan configuration, and in a low-power standby state, the blades are adjusted to a feathering position to reduce aerodynamic drag.

[0011] In some embodiments, controlling the manned UAV to land safely according to the thrust distribution scheme and the emergency response level, until the manned UAV lands and then activating the landing buffer device and cutting off the power supply to all effective thrusters, specifically includes: According to the thrust distribution scheme, the manned UAV is controlled to land along a landing trajectory that matches the emergency response level; When the altitude of the manned drone above the ground is less than or equal to the preset landing buffer trigger altitude threshold, the airbag control unit is triggered to drive the landing buffer airbag to inflate and deploy. Once the ground contact sensor detects a stable ground contact signal, the redundant energy management system will cut off the power supply to all effective thrusters in stages, first the main propulsion thrusters and then the independent backup thrusters.

[0012] Secondly, this application provides a safety control system for a manned unmanned aerial vehicle (UAV) with a backup thruster, used to execute a safety control method for a manned UAV with a backup thruster, including: The fault diagnosis module is used to perform residual evaluation on the operating status parameters of the main propulsion unit through multi-sensor data fusion, and obtain online diagnostic results of the manned UAV in terms of fault type and fault severity. The processing module is used to remove the faulty thruster from the set of effective thrusters based on the online diagnostic results, and select an emergency response level that matches the current fault state from the multi-level protection measures through the mapping relationship between the remaining thrust margin and the preset safety threshold. The processing module is also used to activate and pre-start the independent backup thrusters in a low-power standby state, and then incorporate the independent backup thrusters into the effective thruster set, and obtain the thrust allocation scheme of the effective thrusters in the manned UAV through augmented reconstruction of the control allocation matrix. The execution module is used to control the manned UAV to land safely according to the thrust distribution scheme and the emergency response level, until the manned UAV lands, after which it activates the landing buffer device and cuts off the power supply to all effective thrusters.

[0013] Thirdly, this application provides a computer device including a memory and a processor, the memory storing code, and the processor being configured to acquire the code and execute the above-described manned unmanned aerial vehicle safety control method with a backup thruster.

[0014] Fourthly, this application provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the above-described safety control method for a manned unmanned aerial vehicle with a backup thruster.

[0015] The technical solutions provided by the embodiments disclosed in this application have the following beneficial effects: This application provides a safety control method and system for a manned unmanned aerial vehicle (UAV) with a backup thruster. The method involves using multi-sensor data fusion to perform residual evaluation of the operating status parameters of the main thruster, obtaining online diagnostic results for the UAV in terms of fault type and severity. Based on these online diagnostic results, the faulty thruster is removed from the set of effective thrusters. An emergency response level matching the current fault state is selected from multi-level protection measures using a mapping relationship between remaining thrust margin and a preset safety threshold. Independent backup thrusters in low-power standby mode are activated and pre-started, and then incorporated into the set of effective thrusters. A thrust allocation scheme for the effective thrusters in the UAV is obtained through augmented reconstruction of the control allocation matrix. The UAV is controlled to land safely according to the thrust allocation scheme and the emergency response level, until the landing buffer device is activated and the power supply to all effective thrusters is cut off after landing.

[0016] Therefore, in this application, the manned UAV is controlled to land safely according to the thrust distribution scheme and the emergency response level, until the landing buffer device is activated and the power supply of all effective thrusters is cut off after the manned UAV lands. First, the emergency response level can be determined. The determination of the emergency response level is achieved by quantifying and mapping the remaining thrust margin calculated in real time after the failure with a preset safety threshold. The handling level that is precisely matched with the current actual remaining control capability of the aircraft is automatically selected from the multi-level protection measures. This effectively solves the technical contradiction of existing fault-tolerant control methods that rely solely on the redundant reconstruction of existing thrusters within the system and cannot distinguish the handling strategy due to the depletion of redundant resources in multiple failure scenarios, resulting in "overly risky when the capability is insufficient and overly conservative when the capability is sufficient". This enables the manned UAV to adaptively select the optimal safe landing strategy from the nearest controlled landing to the controlled forced landing and then to the emergency deceleration landing according to the sufficiency of the remaining thrust margin when the main propulsion system fails partially or completely. This significantly improves the handling of extreme failures. The survival probability and handling rationality in fault scenarios are assessed. Then, the thrust allocation scheme is determined. The thrust allocation scheme is determined by merging the independent backup thrusters activated after the failure with the remaining healthy thrusters into an expanded set of effective thrusters. Thrust is redistributed to all effective thrusters based on the augmented control allocation matrix and the weighted pseudo-inverse method. While prioritizing the roll and pitch attitude control torque requirements, the total lift loss is compensated. This overcomes the technical limitations of existing fault-tolerant control methods that rely solely on the redundant reconfiguration of existing actuators within the system. It solves the key problem of no feasible thrust allocation solution when multiple thrusters fail successively in the main propulsion system or when the fault location is special and internal redundant resources are exhausted. This enables the manned UAV to maintain attitude stability and complete a controlled and safe landing even in extreme fault scenarios, significantly enhancing the fault tolerance limit and reliability of the entire safety control system. In summary, based on the above scheme, sufficient power and control margin can still be provided to ensure the safe landing of the manned UAV even when the redundancy of the main propulsion system is exhausted. Attached Figure Description

[0017] Figure 1 This is an exemplary flowchart of a manned unmanned aerial vehicle safety control method with a backup thruster, according to some embodiments of this application; Figure 2 This is an exemplary flowchart illustrating the determination of an emergency response level according to some embodiments of this application; Figure 3 This is a schematic diagram of the structure of a manned unmanned aerial vehicle safety control system with a backup thruster, according to some embodiments of this application; Figure 4 This is a schematic diagram of the structure of a computer device for implementing a safety control method for a manned unmanned aerial vehicle with a backup thruster, according to some embodiments of this application. Detailed Implementation

[0018] To better understand the technical solution of this application, the technical solution of this application will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0019] refer to Figure 1 The figure is an exemplary flowchart of a safety control method for a manned unmanned aerial vehicle with a backup thruster, according to some embodiments of this application. The figure mainly includes the following steps: In step 101, residual evaluation of the operating status parameters of the main propulsion unit is performed by multi-sensor data fusion to obtain online diagnostic results of the manned UAV in terms of fault type and fault severity.

[0020] In some embodiments, the online diagnostic results of the manned UAV in terms of fault type and fault severity can be obtained by residual evaluation of the operating state parameters of the main propulsion unit through multi-sensor data fusion, which can be achieved by the following steps: For each active propulsion unit in a manned UAV, multi-modal operating status parameters are continuously collected by speed sensors, current sensors, temperature sensors, and body vibration sensors installed on the active propulsion unit to obtain the operating status data of the active propulsion unit; The expected rotational speed in the operating status data is compared with the measured rotational speed to obtain the normalized residual signal of the main propulsion thruster, and then the normalized residual signal of each main propulsion thruster in the manned UAV is obtained. Data feature fusion and fault mode matching are performed based on the normalized residual signals and operational status data of all active propulsion units to obtain online diagnostic results for manned UAVs in terms of fault type and fault severity.

[0021] It should be noted that, in this application, the operational status data is a multi-dimensional time series set characterizing the real-time operating conditions and dynamic response of the thruster. By fusing information from multiple physical quantities such as rotational speed, current, temperature, and vibration, it ensures that even when a single sensor signal is affected by noise interference or partial failure, the robustness of fault diagnosis can still be maintained by relying on information from other dimensions, avoiding false alarms and missed faults caused by relying solely on a single rotational speed threshold. The normalized residual signal is a standardized deviation index used to eliminate the influence of differences in the rated operating parameters of the thruster under different flight conditions on fault characterization. It can transform the physical quantity offset caused by the fault under each operating condition into a dimensionless unified fault characteristic metric, so that the fault judgment threshold does not need to be frequently adjusted with changes in flight status. The online diagnostic results are structured fault information indicating the faulty thruster number, fault type, and fault severity level. It can transform the original sensor signals into quantitative fault information that can be directly used for safety decisions, providing accurate and timely fault basis for the selection of subsequent emergency response levels and the reconstruction of the thrust control allocation matrix.

[0022] In practical implementation, firstly, for each active propulsion unit in the manned UAV, a Hall effect speed sensor installed on the drive motor of the active propulsion unit can be used to collect the rotor angular velocity at a sampling frequency of no less than 500 Hz to obtain the speed signal; a shunt current sensor can be used to collect the transient current of the three-phase windings to obtain the current signal; an NTC thermistor embedded in the stator winding can be used to collect the internal temperature of the motor to obtain the temperature signal; and a triaxial microelectromechanical system accelerometer installed at the root of the support arm of the active propulsion unit can be used to collect the body vibration response signal during the operation of the active propulsion unit. Then, the collected speed signal, current signal, temperature signal, and vibration acceleration signal are converted from analog to digital to obtain the motion signal of the active propulsion unit. The system first obtains the operating state data. Then, based on the electrical dynamic equations and rotor dynamic equations of the drive motor of the main propulsion unit, an extended Kalman filter is constructed with stator current vector, rotor angular velocity, and rotor position angle as state variables. The extended Kalman filter is then used to recursively estimate the operating state data of the main propulsion unit. In each recursive cycle, the estimated value of the rotor angular velocity is output as the desired speed. The difference between the desired speed in each recursive cycle and the measured speed collected by the Hall speed sensor is calculated to obtain the original residual sequence of the main propulsion unit. The original residual sequence is then dimensionally normalized and divided by the rated speed value of the main propulsion unit under the current operating condition to obtain the main propulsion unit's operating state data. The normalized residual signal of the device is used. For example, when the difference between the expected speed and the measured speed of the main propulsion thruster under the cruise condition of 4,500 rpm is 900 rpm, the value of its normalized residual signal is 0.2. Finally, for each main propulsion thruster, the normalized residual signal is used as a fault feature parameter. The time-domain peak-to-peak value, kurtosis index of the vibration signal and the harmonic distortion rate of the current signal in the operating state data of the main propulsion thruster are statistically analyzed using the time window of the normalized residual signal as the input feature vector. A fault mode classifier based on the random forest ensemble learning algorithm is used to perform feature-level fusion and fault mode matching on the input feature vector. The fault mode classifier is used to perform mutual... Unrelated decision trees vote on the input feature vectors by category, then count the number of votes for each fault category and output the fault category with the highest number of votes as the fault type. At the same time, the fault severity corresponding to the fault type is output. The set of fault type and fault severity is output as the fault diagnosis result of the main propulsion unit. Finally, all fault diagnosis results with the main propulsion unit identification code are used as the online diagnosis results of the manned UAV in terms of fault type and fault severity. Among them, the fault type includes short circuit between turns of motor winding, demagnetization of permanent magnet, wear of bearing inner ring, damage to propeller structure, and no fault; the fault severity includes four levels: no performance degradation, slight performance degradation, moderate performance degradation, and complete failure.

[0023] In step 102, the faulty thruster is removed from the set of effective thrusters based on the online diagnostic results, and an emergency response level matching the current fault state is selected from the multi-level protection measures through the mapping relationship between the remaining thrust margin and the preset safety threshold.

[0024] In some embodiments, reference Figure 2 The figure is an exemplary flowchart illustrating the determination of an emergency response level according to some embodiments of this application. In this application, the faulty thruster is removed from the set of effective thrusters based on the online diagnostic results, and an emergency response level matching the current fault state is selected from multi-level protection measures through the mapping relationship between the remaining thrust margin and a preset safety threshold. This can be achieved through the following steps: In step 1021, the faulty thruster is determined based on the online diagnostic results; In step 1022, the faulty thruster is removed from the set of effective thrusters and its thrust contribution is deducted from the total thrust of the UAV, thereby calculating the remaining thrust margin of the manned UAV. In step 1023, the remaining thrust margin is compared one by one with the three-level protection threshold preset in the flight controller to obtain the threshold range. In step 1024, an emergency response level matching the current fault state is selected from the multi-level protection measures based on the threshold attribution range.

[0025] It should be noted that, in this application, a faulty thruster refers to a main thruster that is determined to have failed and whose thrust contribution needs to be deducted from the total thrust; the remaining thrust margin refers to the margin of maximum available thrust provided by the UAV's healthy thrusters after a failure, exceeding the minimum thrust baseline required to maintain flight safety. It can quantify the UAV's remaining control capability after a failure into a single comparable numerical indicator, providing a continuous and measurable decision-making basis for the objective selection of the emergency response level; the threshold attribution interval refers to the discrete failure level classification result obtained by mapping the remaining thrust margin, which can transform the continuous physical quantity of thrust margin into a definite failure severity category, providing a unique corresponding decision input for the subsequent selection of the emergency response level, and eliminating repeated jumps in the emergency level caused by instantaneous fluctuations in the remaining thrust margin; the emergency response level refers to a standardized safety handling level matched with the current failure state, which can establish a deterministic mapping between failure scenarios of different severity and differentiated safe landing strategies, enabling the UAV to always execute the optimal safe landing procedure that matches its remaining capability under the condition of limited thrust capability.

[0026] In specific implementation, firstly, based on the main thruster identification code carried in the online diagnostic results, the fault diagnosis results of all main thrusters are traversed one by one through the fault location and level judgment logic. Faulty main thrusters are locked and identified as faulty thrusters, and the thrust attenuation coefficient is extracted based on their fault severity. Secondly, the effective thruster set management module in the flight controller removes the faulty thruster from the set of effective thrusters currently participating in control allocation, and the product of the faulty thruster's maximum available thrust and thrust attenuation coefficient is used as the thrust contribution to be deducted. The sum of the maximum available thrust of all main thrusters of the manned UAV is subtracted from the thrust contribution, and then the minimum thrust reference value required to maintain the UAV's safe hovering and basic attitude control is subtracted to obtain the remaining thrust margin of the manned UAV. Then, the remaining thrust margin is compared with the pre-calibrated and fixed threshold values ​​using a graded threshold comparator. The three-level protection thresholds stored in the non-volatile memory of the flight controller are compared step by step. When the remaining thrust margin is not lower than the first margin threshold, the assigned interval is determined to be the first threshold interval; when the remaining thrust margin is lower than the first margin threshold but not lower than the second margin threshold, the assigned interval is determined to be the second threshold interval; when the remaining thrust margin is lower than the second margin threshold but not lower than the third margin threshold, the assigned interval is determined to be the third threshold interval. The assigned interval determination result is used as the threshold assigned interval. Finally, the threshold assigned interval is received by the emergency response decision unit. When the threshold assigned interval is the first threshold interval, the first emergency response level is selected, i.e., safe controlled landing; when the threshold assigned interval is the second threshold interval, the second emergency response level is selected, i.e., controlled forced landing; when the threshold assigned interval is the third threshold interval, the third emergency response level is selected, i.e., emergency deceleration landing, as the emergency response level matching the current fault state.

[0027] It should be noted that in this application, the three-level protection threshold includes a first thrust margin threshold corresponding to safe flight and controlled landing, a second thrust margin threshold corresponding to only satisfying basic attitude control, and a third thrust margin threshold corresponding to only maintaining minimum attitude control.

[0028] In step 103, the independent standby thrusters in low-power standby state are activated and pre-started, and then the independent standby thrusters are incorporated into the effective thruster set. The thrust allocation scheme of the effective thrusters in the manned UAV is obtained by augmenting and reconstructing the control allocation matrix.

[0029] In some embodiments, the activation and pre-start of an independent backup thruster in a low-power standby state can be achieved as follows: First, the power supply channel corresponding to the faulty thruster is cut off by the redundant energy management system, and the backup power module is powered on and activated. The backup power module outputs its rated voltage to the electronic speed controller of the independent backup thruster. For example, the redundant energy management system adopts a redundant hot backup mode, and completes the cutoff of the power supply channel and activation of the backup power module within a preset time after detecting an abnormality in the main power thruster, ensuring that the power supply of the independent backup thruster is not affected by fluctuations in the main power supply. Then, a preset second-order open-loop ramp acceleration curve is applied to the brushless DC motor of the independent backup thruster through the electronic speed controller, and the rotor pre-positioning is performed sequentially. The system consists of three stages: open-loop forced acceleration and closed-loop operation switching, which increases the speed of the independent backup thruster to the minimum operating speed within a preset minimum start-up time. For example, the minimum operating speed is set to 1,500 revolutions per minute, and the preset minimum start-up time is set to 120 milliseconds. Finally, the deviation between the real-time speed and the minimum control speed of the independent backup thruster is detected. When the real-time speed reaches the minimum control speed, the control mode of the independent backup thruster is switched from open-loop acceleration mode to closed-loop torque control mode through the electronic speed governor to maintain continuous and stable thrust output. For example, the minimum control speed is set to 25% to 30% of the rated speed of the independent backup thruster to ensure that a sufficient rotor back electromotive force signal has been established when switching to closed-loop control.

[0030] In some embodiments, incorporating the independent backup thrusters into the effective thruster set and obtaining the thrust allocation scheme of the effective thrusters in the manned UAV through augmented reconstruction of the control allocation matrix can be achieved by the following steps: Once the thrust of the independent backup thruster reaches the minimum control speed, the independent backup thruster and the main power thruster determined to be fault-free in the online diagnostic results are merged into an effective thruster set; An augmented control effectiveness matrix is ​​constructed based on the aforementioned set of effective thrusters; The augmented control effectiveness matrix is ​​solved by weighted pseudo-inverse to obtain the thrust distribution scheme of the effective thrusters in the manned UAV.

[0031] It should be noted that, in this application, the effective thruster set refers to the logical grouping of all thrusters that can participate in thrust output under the current fault state of the UAV. This group provides the control allocation module with a complete set of controlled objects that strictly corresponds to the actual usable state of the current power system, ensuring that subsequent thrust allocation calculations are performed only on thrusters with actual output capabilities. This avoids control response deviations or attitude loss due to sending control commands to failed thrusters, thus forming a reliable fault isolation boundary in terms of control continuity before and after thruster failure. The augmented control effectiveness matrix is ​​a quantitative mapping table describing the ability of each thruster in the effective thruster set to act on each controllable degree of freedom of the UAV. It can represent the dynamic contribution of newly activated standby thrusters in a standardized matrix form. The formula incorporates the control allocation problem, so that after the backup thruster is put into operation, the mathematical model structure of the original control allocation framework of the UAV can be changed to achieve unified and coordinated control of all thrusters. This fundamentally solves the problem of rank deficiency or divergence of the control matrix caused by sudden changes in the number of actuators in conventional control reconfiguration schemes. The thrust allocation scheme is a complete thrust setpoint sequence within the thrust boundary constraints of each effective thruster. It can be used as the basis for direct control commands output by the flight controller to the electronic speed governor of each thruster. Under the premise of prioritizing the roll and pitch attitude control torque requirements of the UAV, it achieves the global optimal allocation of thrust resources. When the total thrust is insufficient, it automatically concentrates the limited thrust in the attitude stabilization direction, thereby improving the attitude controllability during the safe landing phase after a failure.

[0032] In specific implementation, firstly, Hall sensor-based speed monitoring technology and shunt resistor-based current detection technology can be used to estimate the thrust establishment status of the independent backup thruster in real time. When the actual speed of the backup thruster motor enters the preset minimum operating speed range and the winding current stabilizes within the current range corresponding to the steady-state thrust output, it is determined that the thrust of the independent backup thruster has reached the minimum control speed. Then, the independent backup thruster whose thrust has reached the minimum control speed is merged with the remaining active thruster determined to be fault-free in the online diagnostic results into a temporary thruster group. At the same time, the three-dimensional thrust vector of each thruster in the temporary thruster group in the body coordinate system and its relative thrust are recorded in the form of a thruster thrust coefficient matrix. The three-dimensional moment arm vector at the center of mass of the UAV is used to group these temporary thrusters into the effective thruster set. Then, based on the original control efficiency matrix under normal flight conditions of the UAV, the thrust coefficient and moment coefficient are extracted for each thruster in the effective thruster set. The thrust coefficient is determined by the slope of the thrust-speed mapping curve of the thruster at the desired speed point, and the moment coefficient is calculated by the vector product of the thrust coefficient and the moment arm vector of the thruster. All the extracted thrust coefficients and moment coefficients are then arranged in the order of first the healthy active thrusters and then the backup thrusters to construct an initial augmented control efficiency matrix with the same number of columns as the total number of thrusters in the effective thruster set and the same number of rows as the number of controllable degrees of freedom of the UAV. In the initial augmented control effectiveness matrix, each column corresponds to the control effectiveness contribution of a thruster in each controllable degree of freedom direction. A placeholder column vector is appended to the rightmost side of the initial augmented control effectiveness matrix. The number of elements in the placeholder column vector is equal to the number of controllable degrees of freedom, and each element is zero. This ensures that the number of columns in the initial augmented control effectiveness matrix exceeds the total number of thrusters by one column, forming the augmented control effectiveness matrix used for optimization. Finally, a weight matrix for the thruster health status is introduced. This weight matrix consists of health coefficients calculated from the severity of each thruster's fault in the online diagnostic results. For example, a completely failed thruster corresponds to zero weight, a fault-free thruster corresponds to unit weight, and thrusters with partial performance degradation are assigned weights ranging from zero to unit according to their degree of degradation. The intermediate value between the values ​​is used as input, along with the augmented control effectiveness matrix, weight matrix, and the desired three-axis thrust and desired three-axis control torque output by the flight controller. A thrust allocation solver with a weighted pseudo-inverse as its core is constructed. This thrust allocation solver first calculates the Moore-Penrose generalized inverse of the weighted control effectiveness matrix, then multiplies the Moore-Penrose generalized inverse with the desired thrust-torque vector to obtain the initial allocation solution. Subsequently, the components in the initial allocation solution that exceed the upper and lower limits of thrust for each thruster are clipped to the corresponding constraint boundaries one by one. The clipped allocation vector is then substituted back into the generalized inverse solution process for iterative correction until the error converges. Finally, the allocation result that satisfies all thrust boundary constraints is used as the thrust allocation scheme for the effective thrusters in the manned UAV.

[0033] In step 104, the manned UAV is controlled to land safely according to the thrust distribution scheme and the emergency response level until the manned UAV lands, after which the landing buffer device is activated and the power supply of all effective thrusters is cut off.

[0034] In some embodiments, controlling the manned UAV to land safely according to the thrust distribution scheme and the emergency response level, until the manned UAV lands and activates the landing buffer device and cuts off the power supply to all effective thrusters, can be achieved by the following steps: According to the thrust distribution scheme, the manned UAV is controlled to land along a landing trajectory that matches the emergency response level; When the altitude of the manned drone above the ground is less than or equal to the preset landing buffer trigger altitude threshold, the airbag control unit is triggered to drive the landing buffer airbag to inflate and deploy. Once the ground contact sensor detects a stable ground contact signal, the redundant energy management system will cut off the power supply to all effective thrusters in stages, first the main propulsion thrusters and then the independent backup thrusters.

[0035] In practice, firstly, the flight controller converts the thrust commands of each effective thruster in the thrust distribution scheme into corresponding speed control signals, and controls each effective thruster to execute a landing trajectory matching the emergency response level. Specifically, when the emergency response level is Level 1, the UAV is controlled to fly along a predetermined glide path at a preset equilibrium descent rate to perform a controlled landing. When the emergency response level is Level 2, the UAV is controlled to descend at a controllable rate while maintaining controlled roll and pitch attitudes, and autonomously searches for a suitable emergency landing area using the onboard visual perception module. When the emergency response level is Level 3, all effective thrusters are controlled to operate at their maximum safe power in conjunction with the fuselage aerodynamic drag configuration to perform a gentle landing. Simultaneously, the actual flight state parameters corresponding to this thrust distribution scheme are fed back to the flight controller to form a closed-loop trajectory tracking during the landing process. Then, during landing, the onboard altitude sensor monitors the UAV's distance from the ground. The altitude is monitored in real time, and the data is transmitted to the airbag control unit. The airbag control unit compares the ground clearance with a preset landing buffer trigger height threshold. When the ground clearance is less than or equal to the preset landing buffer trigger height threshold, the airbag control unit drives the gas generator to inflate the airbag, causing the airbag to quickly inflate and deploy from a folded state to a buffer working state. The airbag material absorbs landing kinetic energy through compression deformation during the landing impact to reduce the impact overload transmitted to the aircraft. At the same time, the airbag inflation and deployment state is used as a landing buffer completion signal. Finally, after the ground contact sensor detects that the continuous contact time between the UAV and the ground exceeds the preset stable ground contact determination time, a stable ground contact signal is generated. After receiving the stable ground contact signal, the redundant energy management system performs the thruster power supply cut-off operation in stages according to the sequence of first cutting off the main propulsion thruster power supply circuit and then cutting off the independent backup thruster power supply circuit. The state that all effective thrusters are de-energized is used as a sign that the safe landing process is completed.

[0036] In another aspect, in some embodiments, this application provides a safety control system for a manned unmanned aerial vehicle with a backup thruster, referencing... Figure 3 The figure is a schematic diagram of the structure of a manned unmanned aerial vehicle (UAV) safety control system with a backup thruster according to some embodiments of this application, including: a fault diagnosis module 201, a processing module 202, and an execution module 203, which are described below: The fault diagnosis module 201 in this application is mainly used to perform residual evaluation on the operating status parameters of the main propulsion thruster through multi-sensor data fusion, and obtain online diagnostic results of the manned UAV in terms of fault type and fault severity. Processing module 202, in this application, is used to remove the faulty thruster from the set of effective thrusters based on the online diagnostic results, and select an emergency response level that matches the current fault state from the multi-level protection measures through the mapping relationship between the remaining thrust margin and the preset safety threshold. It should be noted that the processing module 202 is also used to activate and pre-start the independent backup thrusters in the low-power standby state, thereby incorporating the independent backup thrusters into the effective thruster set, and obtaining the thrust allocation scheme of the effective thrusters in the manned UAV through augmented reconstruction of the control allocation matrix. The execution module 203 in this application is mainly used to control the manned UAV to land safely according to the thrust distribution scheme and the emergency response level, until the manned UAV lands, activates the landing buffer device and cuts off the power supply of all effective thrusters.

[0037] The foregoing detailed examples of a manned unmanned aerial vehicle (UAV) safety control method and system with a backup thruster provided in this application. It is understood that the corresponding apparatus, in order to achieve the above functions, includes hardware structures and / or software modules corresponding to the execution of each function. Those skilled in the art should readily recognize that, based on the units and algorithm steps of the examples described in conjunction with the embodiments disclosed herein, this application can be implemented in hardware or a combination of hardware and computer software. Whether a function is executed by hardware or by computer software driving hardware depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specified application, but such implementation should not be considered beyond the scope of this application.

[0038] In some embodiments, this application also provides a computer device, the computer device including a memory and a processor, the memory for storing a computer program, and the processor for calling and running the computer program from the memory, so that the computer device performs the above-described manned unmanned aerial vehicle safety control method with a backup thruster.

[0039] In some embodiments, reference Figure 4 The dashed lines in the figure indicate that the unit or module is optional. This figure is a structural schematic diagram of a computer device for implementing a safety control method for a manned unmanned aerial vehicle with a backup thruster according to an embodiment of this application. The safety control method for a manned unmanned aerial vehicle with a backup thruster described in the above embodiments can be achieved through… Figure 4 The computer device shown is used to implement this, and the computer device includes at least one processor 301, a memory 302 and at least one communication unit 305. The computer device may be a terminal device, a server or a chip.

[0040] Processor 301 can be a general-purpose processor or a special-purpose processor. For example, processor 301 can be a central processing unit (CPU), which can be used to control computer devices, execute software programs, and process data from software programs. The computer device may also include a communication unit 305 for inputting (receiving) and outputting (transmitting) signals.

[0041] For example, the computer device may be a chip, and the communication unit 305 may be the input and / or output circuit of the chip, or the communication unit 305 may be the communication interface of the chip, which may be a component of a terminal device, network device or other device.

[0042] For example, the computer device may be a terminal device or a server, and the communication unit 305 may be a transceiver of the terminal device or the server, or the communication unit 305 may be a transceiver circuit of the terminal device or the server.

[0043] The computer device may include one or more memories 302 storing a program 304. The program 304 can be executed by a processor 301 to generate instructions 303, causing the processor 301 to execute the method described in the above method embodiments according to the instructions 303. Optionally, the memory 302 may also store data (such as a target audit model). Optionally, the processor 301 may also read data stored in the memory 302, which may be stored at the same storage address as the program 304, or it may be stored at a different storage address than the program 304.

[0044] The processor 301 and memory 302 can be configured separately or integrated together, for example, integrated on the system on chip (SOC) of the terminal device.

[0045] It should be understood that each step of the above method embodiment can be completed by hardware logic circuits or software instructions in the processor 301. The processor 301 can be a CPU, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic devices, such as discrete gates, transistor logic devices, or discrete hardware components.

[0046] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0047] For example, in some embodiments, this application also provides a computer-readable storage medium storing instructions or code that, when executed on a computer, cause the computer to implement the above-described safety control method for a manned unmanned aerial vehicle with a backup thruster.

[0048] Although preferred embodiments of this application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this application.

[0049] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. A manned drone safety control method with a backup thruster, characterized in that, Includes the following steps: By using multi-sensor data fusion to perform residual evaluation on the operating status parameters of the main propulsion system, online diagnostic results for manned UAVs in terms of fault type and fault severity are obtained. Based on the online diagnostic results, the faulty thruster is removed from the set of effective thrusters, and an emergency response level matching the current fault state is selected from the multi-level protection measures through the mapping relationship between the remaining thrust margin and the preset safety threshold. The independent standby thrusters in low-power standby state are activated and pre-started, and then the independent standby thrusters are incorporated into the effective thruster set. The thrust distribution scheme of the effective thrusters in the manned UAV is obtained by augmenting and reconstructing the control allocation matrix. According to the thrust distribution scheme and the emergency response level, the manned UAV is controlled to land safely until the manned UAV lands, after which the landing buffer device is activated and the power supply of all effective thrusters is cut off.

2. The method of claim 1, wherein, By performing residual evaluation on the operating status parameters of the main propulsion system through multi-sensor data fusion, online diagnostic results for manned UAVs in terms of fault type and severity are obtained, specifically including: For each active propulsion unit in a manned UAV, multi-modal operating status parameters are continuously collected by speed sensors, current sensors, temperature sensors, and body vibration sensors installed on the active propulsion unit to obtain the operating status data of the active propulsion unit; The expected rotational speed in the operating status data is compared with the measured rotational speed to obtain the normalized residual signal of the main propulsion thruster, and then the normalized residual signal of each main propulsion thruster in the manned UAV is obtained. Data feature fusion and fault mode matching are performed based on the normalized residual signals and operational status data of all active propulsion units to obtain online diagnostic results for manned UAVs in terms of fault type and fault severity.

3. The method of claim 1, wherein, Based on the online diagnostic results, the faulty thruster is removed from the set of effective thrusters, and an emergency response level matching the current fault state is selected from multi-level protection measures through the mapping relationship between the remaining thrust margin and the preset safety threshold. Specifically, this includes: The faulty thruster was identified based on the online diagnostic results. The faulty thruster is removed from the set of effective thrusters and its thrust contribution is deducted from the total thrust of the UAV, thereby calculating the remaining thrust margin of the manned UAV. The remaining thrust margin is compared one by one with the three-level protection threshold preset in the flight controller to obtain the threshold range. Based on the threshold range, an emergency response level matching the current fault state is selected from multi-level protection measures.

4. The method of claim 1, wherein, The fault types include short circuits between motor winding turns, demagnetization of permanent magnets, wear of bearing inner rings, damage to propeller structure, and no faults.

5. The method of claim 4, wherein, Incorporating the independent backup thrusters into the effective thruster set and obtaining the thrust allocation scheme for the effective thrusters in the manned UAV through augmented reconstruction of the control allocation matrix specifically includes: Once the thrust of the independent backup thruster reaches the minimum control speed, the independent backup thruster and the main power thruster determined to be fault-free in the online diagnostic results are merged into an effective thruster set; An augmented control effectiveness matrix is ​​constructed based on the aforementioned set of effective thrusters; The augmented control effectiveness matrix is ​​solved by weighted pseudo-inverse to obtain the thrust distribution scheme of the effective thrusters in the manned UAV.

6. The method of claim 1, wherein, The independent backup thruster adopts a ducted fan configuration. In low-power standby mode, the blades are adjusted to the feathering position to reduce aerodynamic drag.

7. The method of claim 1, wherein, Controlling the manned UAV to land safely according to the thrust distribution scheme and the emergency response level, until the manned UAV lands and then activating the landing buffer device and cutting off the power supply to all effective thrusters, specifically includes: According to the thrust distribution scheme, the manned UAV is controlled to land along a landing trajectory that matches the emergency response level; When the altitude of the manned drone above the ground is less than or equal to the preset landing buffer trigger altitude threshold, the airbag control unit is triggered to drive the landing buffer airbag to inflate and deploy. Once the ground contact sensor detects a stable ground contact signal, the redundant energy management system will cut off the power supply to all effective thrusters in stages, first the main propulsion thrusters and then the independent backup thrusters.

8. A manned drone safety control system with a backup propeller for executing the manned drone safety control method with a backup propeller according to any one of claims 1 to 7, characterized in that, include: The fault diagnosis module is used to perform residual evaluation on the operating status parameters of the main propulsion unit through multi-sensor data fusion, and obtain online diagnostic results of the manned UAV in terms of fault type and fault severity. The processing module is used to remove the faulty thruster from the set of effective thrusters based on the online diagnostic results, and select an emergency response level that matches the current fault state from the multi-level protection measures through the mapping relationship between the remaining thrust margin and the preset safety threshold. The processing module is also used to activate and pre-start the independent backup thrusters in a low-power standby state, and then incorporate the independent backup thrusters into the effective thruster set, and obtain the thrust allocation scheme of the effective thrusters in the manned UAV through augmented reconstruction of the control allocation matrix. The execution module is used to control the manned UAV to land safely according to the thrust distribution scheme and the emergency response level, until the manned UAV lands, after which it activates the landing buffer device and cuts off the power supply to all effective thrusters.

9. A computer device, comprising: The computer device includes a memory and a processor, the memory storing code, and the processor being configured to retrieve the code and execute the manned unmanned aerial vehicle safety control method with a backup thruster as described in any one of claims 1 to 7.

10. A computer-readable storage medium storing a computer program, the computer program comprising instructions that, when executed by a computer, cause the computer to perform the method of any one of claims 1-9. When the computer program is executed by the processor, it implements the manned unmanned aerial vehicle safety control method with a backup thruster as described in any one of claims 1 to 7.

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