Tilting six-rotor power system failure disposal method and device

Abstract

The invention discloses a tilting six-rotor power system failure disposal method and device, and relates to the technical field of unmanned aerial vehicles. Monitoring control parts related to the power system in real time, collecting core data, and analyzing and processing the core data to judge the fault type of the power system; determining a power coefficient of the power system under the current fault type, establishing a control matrix after failure, and establishing a new control distribution matrix based on the control matrix after failure; and different control and coping strategies are adopted for the unmanned aerial vehicle based on the fault type, the new control distribution matrix, different power system failure numbers and power state conditions. The technical problem of how to quickly formulate a scientific and reasonable coping strategy when a power system fails, maintain the stable flight attitude of the unmanned aerial vehicle to the greatest extent, and ensure that the unmanned aerial vehicle can return safely or land forcibly when part of power fails is solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of unmanned aerial vehicles, in particular to a tilt six-rotor power system failure disposal method and device. BACKGROUND

[0002] The tilt-rotor unmanned aerial vehicle combines the advantages of traditional helicopters and fixed-wing unmanned aerial vehicles, and has the ability of vertical take-off and hovering in the air, and can realize high-speed flight, and also has a large range, endurance and load capacity.

[0003] The tilt-rotor unmanned aerial vehicle faces the risk of power system failure in the flight process. As the core component of the tilt-rotor unmanned aerial vehicle, the normal operation of the power system is the key to ensuring the flight safety of the unmanned aerial vehicle. Once the power system fails, the unmanned aerial vehicle will lose enough lift and propulsion, which will easily lead to the loss of control of the aircraft and cause it to crash. This not only causes the loss of expensive unmanned aerial vehicle equipment, but also poses a serious threat to the safety of ground personnel and property, and causes huge life and property losses.

[0004] Therefore, how to quickly develop a scientific and reasonable response strategy when the power system fails, to maximize the maintenance of the stable flight attitude of the unmanned aerial vehicle, and to ensure that the unmanned aerial vehicle can safely return or land when part of the power fails, has become a technical problem to be solved. SUMMARY

[0005] In the embodiments of the present application, by providing a tilt six-rotor power system failure disposal method, the technical problem of how to quickly develop a scientific and reasonable response strategy when the power system fails, to maximize the maintenance of the stable flight attitude of the unmanned aerial vehicle, and to ensure that the unmanned aerial vehicle can safely return or land when part of the power fails, is solved.

[0006] In the first aspect, the embodiments of the present application provide a tilt six-rotor power system failure disposal method, which comprises: monitoring the operating components involved in the power system in real time, collecting core data and performing analysis and processing to determine the fault type of the power system; determining the power coefficient of the power system under the current fault type, establishing a control matrix after failure, and establishing a new control distribution matrix based on the control matrix after failure; based on the fault type and the new control distribution matrix, as well as different numbers of power system failures and power states, different control and response strategies are adopted for the unmanned aerial vehicle.

[0007] In a possible implementation, the fault types include power system power shortage, power system overload, power system failure, tilting nacelle jamming, tilting actuator feedback failure, total pitch control failure, rotor partial failure, and rotor failure; the power system power shortage is determined by low output voltage; the power system overload is determined by simultaneous occurrence of low output voltage, large power system current, and high output power; the power system failure is determined by simultaneous occurrence of low rotor speed, low output power, and high motor temperature; the tilting nacelle jamming is determined by inconsistency between the feedback value and the command value of the actuator tilt angle; the tilting actuator feedback failure is determined by tilting actuator state feedback failure; the total pitch control failure is determined by total pitch actuator state feedback failure; the rotor partial failure is determined by simultaneous occurrence of low output power and low rotor speed; and the rotor failure is determined by rotor speed state feedback failure.

[0008] In a possible implementation, the determining the power coefficient of the power system under the current fault type, establishing the post-failure control matrix, and establishing the new control distribution matrix based on the post-failure control matrix include: applying the power coefficient of the power system under the current fault type to a corresponding element of the original control matrix of the power system to obtain the post-failure control matrix; and establishing the new control distribution matrix based on the post-failure control matrix. obtaining the new control distribution matrix; wherein, is the original control matrix, is the control distribution matrix, is a virtual control quantity of the four control channels, is the post-failure control matrix, is the new control distribution matrix; and the unmanned aerial vehicle is controlled to fly based on the post-failure control matrix and the new control distribution matrix.

[0009] In a possible implementation, the original control matrix includes a rotor total pitch control matrix and an aerodynamic rudder and throttle control matrix, and the control distribution matrix includes a rotor total pitch control distribution matrix and an aerodynamic rudder and throttle control distribution matrix; the determining the power coefficient of the power system under the current fault type, establishing the post-failure control matrix, and establishing the new control distribution matrix based on the post-failure control matrix include: applying the power coefficient of the power system under the current fault type to a corresponding element of the rotor total pitch control matrix of the power system to obtain the post-failure rotor total pitch control matrix; and establishing the new rotor total pitch control distribution matrix based on the post-failure rotor total pitch control matrix. obtaining the post-failure rotor total pitch control matrix; wherein, is the rotor total pitch control matrix, is the rotor total pitch control distribution matrix, is the post-failure rotor total pitch control matrix, is the new rotor total pitch control distribution matrix, is the tilt angle of the rotor; controlling the unmanned aerial vehicle to fly based on the failed control matrix, the new control distribution matrix, and the aerodynamic rudder and throttle control matrix, and the aerodynamic rudder and throttle control distribution matrix.

[0010] In a possible implementation, different control and response strategies are taken for the unmanned aerial vehicle based on the failure type and the new control distribution matrix, and the number of different power system failures and power state conditions, including: in the case of single power system failure or partial failure, the unmanned aerial vehicle is ensured to fly normally by resetting the control distribution matrix; and / or in the case of simultaneous failure or simultaneous partial failure of two power systems, the unmanned aerial vehicle is completed to land by resetting the control distribution matrix and developing a control strategy; and / or in the case of insufficient power during flight of the unmanned aerial vehicle, a transition mode allowing flight altitude to be lowered is adopted.

[0011] In a possible implementation, the case of simultaneous failure or simultaneous partial failure of two power systems is divided into no additional power failure, power partial failure, power substantial failure, and attitude partial failure; the control strategy in the case of no additional power failure includes: in the case of failure of two diagonal rotors, the unmanned aerial vehicle is ensured to normally return and land by resetting the control distribution matrix to ensure complete attitude control; the control strategy in the case of power partial failure includes: in the case of simultaneous failure of two rotors at different longitudinal positions and different from the diagonal rotors, the unmanned aerial vehicle is ensured to normally return by resetting the control distribution matrix to ensure complete attitude control and preferentially selecting the fixed-wing mode; if in the transition mode, the flight speed is preferentially ensured, the flight altitude is allowed to be lowered during transition mode flight, and the unmanned aerial vehicle is slowly descended in the landing area after switching to the helicopter mode to complete landing; the control strategy in the case of power substantial failure includes: in the case of failure of rotors at the same longitudinal position, the unmanned aerial vehicle is ensured to normally return by resetting the control distribution matrix to ensure complete attitude control and preferentially selecting the fixed-wing mode; if in the helicopter mode, the flight speed is preferentially ensured, and the unmanned aerial vehicle is slowly descended in the landing area to complete landing; the control strategy in the case of attitude partial failure includes: in the case of failure of two rotors on the wing, the unmanned aerial vehicle is ensured to return in the fixed-wing mode by preferentially ensuring roll angle and pitch angle control in flight, yaw angle stability is provided by the vertical tail, and the remaining four power systems provide sufficient power, so that the unmanned aerial vehicle is returned and landed.

[0012] In a possible implementation, the transition mode allowing flight height to be reduced is adopted when the power is insufficient during the flight of the UAV, including: the pulling force is increased to the maximum when the attitude of the UAV is stable; the gravity potential energy is converted into kinetic energy to maintain the flight speed by adjusting the pitch angle during the transition from the fixed-wing mode to the helicopter mode; the lift restriction is removed, and a constraint condition is set; the constraint condition relates to the balance relationship among the pulling force of the rotor, the resistance and the gravity component; the gravity component is related to the pitch angle; the constraint condition includes that the pitch angle instruction value is related to the lifting speed; the relative height of the UAV when it starts to enter the transition mode is greater than a preset threshold, indicating that the airspeed is greater than the minimum speed boundary determined by the transition corridor.

[0013] In a second aspect, the embodiments of the present application provide a tilt six-rotor power system failure disposal device, which comprises: a monitoring module, configured to monitor the operating components involved in the power system in real time, collect core data and perform analysis and processing to determine the fault type of the power system; an establishment module, configured to determine the power coefficient of the power system under the current fault type, establish a control matrix after failure, and establish a new control distribution matrix based on the control matrix after failure; and a control module, configured to take different control and response strategies for the UAV based on the fault type and the new control distribution matrix, as well as different numbers of power system failures and power states.

[0014] In a third aspect, the embodiments of the present application provide a tilt six-rotor power system failure disposal server, comprising a memory and a processor; the memory is configured to store computer executable instructions; and the processor is configured to execute the computer executable instructions to implement the method in the first aspect or any possible implementation manner of the first aspect.

[0015] In a fourth aspect, the embodiments of the present application provide a computer readable storage medium, which stores executable instructions, and a computer executes the executable instructions to implement the method in the first aspect or any possible implementation manner of the first aspect.

[0016] The one or more technical solutions provided in the embodiments of the present application have at least the following technical effects: The embodiment of the present application provides a tilt six-rotor power system failure disposal method, which realizes accurate and timely fault identification by monitoring the operating components involved in the unmanned aerial vehicle power system in real time, and collecting core data for analysis and processing to determine the fault type. Different fault types will cause different power characteristics of the power system to change, the power coefficient of the power system under the current fault type is determined, the control matrix after failure is established, and a new control distribution matrix is established based on the control matrix after failure, which can better adapt to the power output under the fault state, and provides strong support for the stable control of the unmanned aerial vehicle under the fault condition. Based on the fault type and the new control distribution matrix, as well as different power system failure quantities and power state conditions, different control and response strategies are adopted for the unmanned aerial vehicle, which greatly improves the safety and reliability of the unmanned aerial vehicle. The technical problem of how to quickly develop a scientific and reasonable response strategy when the power system fails, and maintain the stable flight attitude of the unmanned aerial vehicle to the greatest extent, and ensure that the unmanned aerial vehicle can safely return or land when part of the power fails. BRIEF DESCRIPTION OF DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the description of the embodiments of the present application or the prior art. Obviously, the drawings in the following description are some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0018] Figure 1 A flow chart of a tilt six-rotor power system failure disposal method provided by the embodiment of the present application is provided. Figure 2 A composition schematic diagram of a fault monitoring system provided by the embodiment of the present application is provided. Figure 3 A schematic diagram of an unmanned aerial vehicle tilt six-rotor is provided for the embodiment of the present application. Figure 4 A schematic diagram of a tilt six-rotor power system failure disposal device provided by the embodiment of the present application is provided. Figure 5 A schematic diagram of a tilt six-rotor power system failure disposal server provided by the embodiment of the present application is provided. DETAILED DESCRIPTION

[0019] The technical solutions in the embodiments of the present application will be described clearly and completely in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the protection scope of the present application.

[0020] The following description of the technology involved in the embodiments of the present application is made to facilitate understanding, and should be considered merely as exemplary. Therefore, those of ordinary skill in the art should recognize that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of the present application. Also, for the sake of clarity and conciseness, the following description omits the description of some well-known functions and structures.

[0021] The embodiments of the present application provide a failure handling method for a tilting six-rotor power system, as shown in the figure, which comprises steps S101 to S103. Among them, Figure 1 Figure 1 The steps shown in the figure can be executed in parallel or in reverse. Figure 1

[0022] S101: Real-time monitoring of the operating components involved in the power system, collecting core data and performing analysis and processing to determine the fault type of the power system.

[0023] S102: Determine the power coefficient of the power system under the current fault type, establish the control matrix after failure, and establish a new control distribution matrix based on the control matrix after failure.

[0024] Figure 2 The composition diagram of the fault monitoring system provided by the embodiments of the present application is shown. The fault monitoring system is used for real-time monitoring of the operating components involved in the power system. The operating components monitored specifically include rotors, engines or motors. The monitoring system is composed of Hall sensors, ADC sampling modules, temperature sensors, photoelectric sensors and servo self-checking modules. The system measures the rotor speed, phase sequence alternating frequency, output voltage, output current and motor temperature and other parameters, and analyzes and processes these data, thereby comprehensively obtaining the working state of the unmanned aerial vehicle rotor. Based on the current working state, the fault type of the power system and the power coefficient of the power system under the current fault type can be determined.

[0025] Table 1: Failure criterion table for tilting rotors

[0026] Table 1 is a failure criterion table for tilting rotors. The fault types include power system power supply shortage, power system load overload, power system failure, tilting nacelle jamming, tilting servo feedback failure, total distance control failure, rotor partial failure and rotor failure.

[0027] The power system power supply shortage is taken as the criterion for low output voltage.

[0028] ​​Specifically, when the output voltage is too low, it is determined that the power system is underpowered. This fault usually occurs when the battery is underpowered or the engine is underpowered. If only the output voltage decreases without other accompanying phenomena, it can be considered that the power system can still use part of the power. The power coefficient of the power system underpowered is 0.7, that is, the usable power is 70% of the normal working power.

[0029] The power system is overloaded, and the output voltage is low, the power system current is large, and the output power is high at the same time as the criterion.

[0030] Specifically, the power system overload is usually caused by excessive rotor counter torque, accompanied by a small decrease in voltage, a large increase in current, and a large increase in power. Reducing the total pitch of the rotor can reduce the load, but also means a decrease in available power. The power coefficient of the power system overload is determined to be 0.5, that is, the available power is reduced to 50% of the previous value.

[0031] The power system failure is determined by the low rotor speed, low output power, and high motor temperature at the same time.

[0032] Specifically, power system failure is mostly caused by motor damage (such as short circuit, jamming, etc.). At this time, the power system cannot work normally, and to avoid further damage, the power supply to the motor needs to be cut off to make it stop rotating. The power coefficient is determined to be 0, that is, there is no available power.

[0033] The tilt nacelle jamming is determined by the inconsistency between the feedback value and the command value of the steering machine tilt angle. The power coefficient of the tilt nacelle jamming is calculated according to the tilt angle interpolation.

[0034] Specifically, the tilt nacelle jamming is mainly caused by tilt steering machine or structural failure, which is manifested by the inconsistency between the feedback value and the command value of the steering machine tilt angle. To avoid trim problems and make the most of rotor power, adjust the tilt angle of the corresponding other rotor to the same value. The power coefficient is calculated according to the tilt angle interpolation. Trim refers to the state of keeping the moment balance of the unmanned aerial vehicle during flight, that is, the resultant moment in each direction is zero, so as to ensure that the unmanned aerial vehicle can fly stably and will not have unnecessary attitude changes such as pitch, roll or yaw.

[0035] The tilt steering machine feedback failure is determined by the tilt steering machine state feedback failure.

[0036] Specifically, when the tilt steering machine feedback failure occurs, the steering machine tilt angle cannot be determined, and the additional moment caused by the rotor cannot be handled. To avoid control and trim problems, the rotor is stopped, and the power coefficient is 0, that is, there is no available power.

[0037] The total pitch control failure is determined by the total pitch steering machine state feedback failure.

[0038] Specifically, total distance manipulation failure is usually caused by total distance steering machine stuck, steering machine cannot adjust total distance, cannot adjust rotor tension through total distance control, to avoid control and trim problem, make the rotor stop, power coefficient is 0, no available power.

[0039] Rotor partial failure occurs simultaneously as a criterion of low output power and low rotor speed.

[0040] Specifically, rotor partial failure is mainly caused by structural failure, and the power coefficient is determined as 0.5, that is, the available power is 50% of normal operation.

[0041] Rotor failure takes rotor speed state feedback failure as a criterion.

[0042] Specifically, rotor failure is usually caused by structural failure, and is more serious than rotor partial failure, such as rotor stuck. To avoid further damage, make the motor stop, power coefficient is 0, no available power.

[0043] S103: Based on the fault type and the new control allocation matrix, as well as the different number of power system failures and power state, different control and coping strategies are taken for the unmanned aerial vehicle.

[0044] Determine the power coefficient of the power system under the current fault type, establish the failure control matrix, and establish a new control allocation matrix based on the failure control matrix, including the following contents.

[0045] Apply the power coefficient of the power system under the current fault type to the corresponding elements of the original control matrix of the power system to obtain the failure control matrix.

[0046] Based on Obtain a new control allocation matrix. Wherein, is the original control matrix, is the control allocation matrix, is the virtual control amount of the four control channels, is the failure control matrix, is the new control allocation matrix. , is the virtual control amount of the rotor tension channel, is the virtual control amount of the roll channel, is the virtual control amount of the pitch channel, is the virtual control amount of the yaw channel.

[0047] Control the unmanned aerial vehicle to fly based on the failure control matrix and the new control allocation matrix.

[0048] The original control matrix includes the rotor collective pitch control matrix and the aerodynamic control surfaces and throttle control matrix, while the control allocation matrix includes the rotor collective pitch control allocation matrix and the aerodynamic servo and throttle control allocation matrix.

[0049] Apply the power coefficient of the power system under the current fault type to the corresponding elements of the rotor collective pitch control matrix of the power system to obtain the rotor collective pitch control matrix after failure.

[0050] based on Obtain the rotor collective pitch control matrix after failure. Wherein, This is the rotor collective pitch control matrix. Assign a matrix to the rotor collective pitch control. This is the rotor collective pitch control matrix after failure. Assign a matrix to the new rotor collective pitch control. This refers to the rotor tilt angle.

[0051] The UAV is controlled based on the control matrix after failure, the new control allocation matrix, and the aerodynamic control surface and throttle control matrix, as well as the aerodynamic servo and throttle control allocation matrix.

[0052] rudder control Virtual control quantities with four control channels The relationship is: That is, the virtual control quantities of the four control channels are allocated to the actual control surface manipulation quantities.

[0053] When the dynamic system fails, the state transition matrix is... The effect (composed of stability derivatives) is small and can be ignored, but it affects the control matrix. The impact is significant. To reduce the impact of power system failure on the control law, a new control allocation matrix needs to be established based on the control matrix after the failure, in order to ensure the normal operation of the UAV under partial power failure conditions.

[0054] The dynamic equations of the UAV obtained from the small perturbation linearization model are as follows: .in, The drone is in flight status. Here is the state transition matrix. For the control matrix, This refers to the control surface inputs. Due to the control redundancy characteristics of tilt-hexacoach UAVs, different control allocation methods need to be designed for helicopter mode, transition mode, and fixed-wing mode.

[0055] Typically, the new control allocation matrix can be calculated using the generalized inverse method. The formula is: However, due to the redundancy in the control of a six-rotor aircraft, the control matrix after a failure... Not full rank matrix, so The left inverse of the generalized inverse does not exist. The original control matrix and the control distribution matrix can be divided into two parts: , . Among them, is the rotor collective control matrix, is the rotor collective control distribution matrix, which is valid in helicopter mode, is the aerodynamic rudder and throttle control matrix, is the aerodynamic rudder and throttle control distribution matrix, which is valid in fixed-wing mode. In the transition mode and are valid, and a new control distribution matrix can be recalculated according to the formula . Among them, is the rotor collective control matrix after failure. Since the control distribution of the fixed-wing mode is independent of whether the power system fails or not, when studying the failure of the power system, there is no need to reset the control distribution matrix of this part. According to different failure conditions, a new control distribution matrix is calculated through the above formula.

[0056] Figure 3 is the schematic diagram of the tilt six-rotor unmanned aerial vehicle provided by the embodiment of the application. The unmanned aerial vehicle rotors are numbered 1~6, and the subsequent number is used to indicate the corresponding power system of the rotor. Among them, rotor 1, rotor 4 and rotor 6 are left-handed rotors, and rotor 2, rotor 3 and rotor 5 are right-handed rotors.

[0057] When a single power system fails or a single power system partial failure occurs, the unmanned aerial vehicle has the ability to fly normally and return, but the flight performance will be affected to a certain extent, and the control structure will also change. At this time, a new control distribution matrix needs to be established based on the control matrix after failure to meet the control requirements.

[0058] Take rotor 1 failure as an example to illustrate the calculation method of the new control distribution matrix. In the helicopter mode under normal conditions, the rotor collective control matrix and the rotor collective control distribution matrix have the following expressions.

[0059] . Among them, is the partial derivative of the rotor tension to the rotor collective, which means the change of the rotor tension caused by the manipulation of the rotor collective, is the rotor tension, is the rotor collective, is the yawing moment, is the partial derivative of the rotor counter torque to the rotor collective, is the rotor arm.

[0060] .

[0061] When the rotor 1 fails, the elements related to the rotor 1 in the new control distribution matrix are multiplied by the power coefficient. Assuming that the available power percentage of the rotor 1 is 0, i.e. the power coefficient is 0, the total pitch control matrix of the failed rotor is obtained . .

[0062] The new rotor total pitch control distribution matrix is calculated as follows. The new rotor total pitch control distribution matrix shows that the power coefficient of the rotor 1 is 0, i.e. the rotor 1 is in a state of no power output, and the matrix can satisfy the constraint . For the control distribution in the transition mode, the specific form is more complex, but it can still be calculated according to the given formula. This application only takes the elements in the new rotor total pitch control distribution matrix in the transition mode determined by the cosine and sine of the tilt angle as an example to give the new rotor total pitch control distribution matrix in the transition mode when the rotor 1 fails: . Wherein, is the rotor tilt angle, when is 90° for the helicopter mode and 0° for the fixed-wing mode.

[0063] Since the control distribution in the fixed-wing mode is independent of whether the power system fails or not, in the case of power system failure, it is not necessary to reset the control distribution in the fixed-wing mode, i.e. it is not necessary to set a new control distribution matrix.

[0064] Based on the failure type and the new control distribution matrix, as well as the different number of power system failures and power states, different control and coping strategies are taken for the UAV, including the following.

[0065] In the case of single power system failure or partial failure, the control distribution matrix is reset to ensure normal flight and return of the UAV.

[0066] And / or when two power systems fail or partially fail at the same time, the control distribution matrix is reset and a control strategy is developed to complete the landing.

[0067] Specifically, when three or more power systems fail, the UAV cannot complete the flight, and this case is not discussed.

[0068] And / or if the UAV has insufficient power during flight, a transition mode that allows the flight altitude to be lowered is adopted.

[0069] Specifically, the transition mode is the transition of the UAV from the fixed-wing mode to the helicopter mode.

[0070] Two power systems simultaneously fail or simultaneously partially fail, which is divided into no additional power failure, power partial failure, power failure and attitude partial failure.

[0071] The control strategy in the case of no additional power failure includes: in the case of two sets of diagonal rotors failure, by resetting the control allocation matrix, ensuring complete attitude control, making the UAV return normally and land.

[0072] The two sets of diagonal rotors can be rotor 1 and rotor 3, or rotor 2 and rotor 4.

[0073] The control strategy in the case of power partial failure includes: in the case of non-diagonal rotors and two rotors at different longitudinal positions simultaneously fail, by resetting the control allocation matrix, ensuring complete attitude control, preferentially selecting the fixed-wing mode, making the UAV return normally. If in the transition mode, preferentially ensure the flight speed if the height allows, allow the flight height to be reduced during the transition mode flight, and after switching to the helicopter mode, control the UAV to slowly glide in the emergency landing area to complete the emergency landing.

[0074] The non-diagonal rotors and two rotors at different longitudinal positions can be rotor 1 and rotor 5, or rotor 1 and rotor 6. Of course, it can also be other rotors, which are not limited in the application.

[0075] The control strategy in the case of power failure includes: in the case of rotors at the same longitudinal position fail, by resetting the control allocation matrix, ensuring complete attitude control, preferentially selecting the fixed-wing mode, making the UAV return normally. If in the helicopter mode, preferentially ensure the flight speed if the height allows, control the UAV to slowly glide in the emergency landing area to complete the emergency landing.

[0076] The rotors at the same longitudinal position can be rotor 1 and rotor 2, or rotor 3 and rotor 4.

[0077] The control strategy in the case of attitude partial failure includes: in the case of two sets of rotors on the wings fail, preferentially ensure the roll angle and pitch angle control in flight, the yaw angle is stabilized by the vertical tail, and the remaining four power systems provide sufficient power, making the UAV return in the fixed-wing mode, complete the transition and land.

[0078] The two sets of rotors on the wings can be rotor 5 and rotor 6.

[0079] Specifically, in the case of attitude partial failure, in the helicopter mode and the transition mode, the attitude control of the three axes (roll axis, pitch axis, and yaw axis) of the UAV cannot be guaranteed, and from the mathematical point of view, the generalized inverse matrix There is none. Since in this special case, the new rotor collective control allocation matrix cannot be calculated directly by the conventional method, the specific form of the elements in the new rotor collective control allocation matrix is given directly . .

[0080] If the unmanned aerial vehicle is in a power shortage during flight, a transition mode that allows the flight altitude to be lowered is adopted, including the following.

[0081] The tension is raised to the maximum when the unmanned aerial vehicle is in a stable attitude.

[0082] During the process of switching from the fixed-wing mode to the helicopter mode, the pitch angle is adjusted to convert the gravitational potential energy into kinetic energy to maintain the flight speed.

[0083] Specifically, during the process of switching from the fixed-wing mode to the helicopter mode, the power is gradually reduced, and the conversion of gravitational potential energy can make up for the lack of power to ensure the stability of the flight speed.

[0084] The lift restriction is removed, and a constraint condition is set. The constraint condition involves the balance relationship of the rotor tension, resistance, and gravitational component. Among them, the gravitational component is related to the pitch angle.

[0085] The constraint condition includes: the pitch angle command value is related to the climb rate. When the unmanned aerial vehicle starts to enter the transition mode, the relative height is greater than the preset threshold, and the indicated airspeed is greater than the minimum speed boundary determined by the transition corridor.

[0086] Specifically, the constraint condition involves the balance relationship of the rotor tension, resistance, and gravitational component, and the expression of the force balance constraint is: . Wherein, is the rotor tension, is the rotor tilt angle, is the resistance of the unmanned aerial vehicle in the body axis system, is the mass of the unmanned aerial vehicle, is the acceleration of gravity, is the pitch angle.

[0087] Specifically, the expression of the pitch angle command value is: . Wherein, is the pitch angle command value, is the error of the climb rate, is the proportional coefficient, is the integral coefficient, denotes the differential of time , is the integral operation.

[0088] The unmanned aerial vehicle needs to meet the following conditions when it starts to enter the transition mode. 1. The relative height greater than a preset threshold. The preset threshold can be 300, i.e. .2. Indicating airspeed greater than a minimum speed boundary determined by a transition corridor , i.e. The transition corridor is a conceptual region describing an acceptable speed range during the transition of the UAV from one flight mode (e.g. fixed wing mode) to another flight mode (e.g. helicopter mode).

[0089] The embodiments of the present application also provide a tilt six-rotor power system failure handling device 400, as shown in the figure, which comprises a monitoring module 401, an establishing module 402 and a control module 403. Figure 4

[0090] The monitoring module 401 is used for real-time monitoring of the operating components involved in the power system, collecting core data and performing analysis and processing to determine the fault type of the power system.

[0091] The establishing module 402 is used for determining the power coefficient of the power system under the current fault type, establishing a control matrix after failure, and establishing a new control distribution matrix based on the control matrix after failure.

[0092] The control module 403 is used for taking different control and response strategies for the UAV based on the fault type and the new control distribution matrix, as well as different numbers of power system failures and power state conditions.

[0093] Some of the modules in the device described in the present application can be described in the general context of computer-executable instructions, such as program modules, which are executed by computers. Generally, program modules include routines, programs, objects, components, data structures, classes, etc. that perform particular tasks or implement particular abstract data types. The present application can also be practiced in distributed computing environments where tasks are performed by remote processing devices connected through a communication network. In a distributed computing environment, program modules can be located in both local and remote computer storage media including storage devices.

[0094] The devices or modules described in the above embodiments can be implemented by computer chips or entities, or by products with certain functions. For the convenience of description, the above devices are described as various modules respectively described in terms of functions. In the implementation of the embodiments of the present application, the functions of the modules can be implemented in the same or multiple software and / or hardware. Of course, the modules implementing certain functions can also be implemented by multiple sub-modules or sub-units.

[0095] ​The methods, apparatuses or modules described in the present application can be implemented in a computer readable program code manner. The controller can be implemented in any appropriate manner, for example, the controller can take the form of, for example, a microprocessor or processor and a computer readable medium storing computer readable program code (for example, software or firmware) executable by the (micro)processor, logic gates, switches, an Application Specific Integrated Circuit (ASIC), a programmable logic controller and an embedded microcontroller. Examples of the controller include, but are not limited to, the following microcontrollers: ARC 625D, Atmel AT91SAM, Microchip PIC18F26K20 and Silicone Labs C8051F320. The memory controller can also be implemented as part of the control logic of the memory. Those skilled in the art also know that, in addition to implementing the controller in a pure computer readable program code manner, the same function can also be implemented by logically programming the method steps in the form of logic gates, switches, ASICs, programmable logic controllers and embedded microcontrollers. Therefore, such a controller can be considered as a hardware component, and the means included therein for implementing various functions can also be considered as structures within the hardware component. Alternatively, the means for implementing various functions can even be considered as both a software module implementing the method and a structure within the hardware component.

[0096] As shown in Figure 5 The embodiments of the present application also provide a tilt six-rotor power system failure handling server, including a memory 501 and a processor 502; the memory 501 is used for storing computer executable instructions; the processor 502 is used for executing the computer executable instructions to implement the tilt six-rotor power system failure handling method provided in the above embodiments of the present application.

[0097] The embodiments of the present application also provide a computer readable storage medium, which stores executable instructions. When a computer executes the executable instructions, the tilt six-rotor power system failure handling method provided in the above embodiments of the present application can be implemented.

[0098] From the description of the above embodiments, those skilled in the art can clearly understand that the present application can be implemented by means of software plus necessary hardware. Based on such an understanding, the technical solutions of the present application can be embodied in the form of a software product or can be embodied in the implementation process of data migration. The computer software product can be stored in a storage medium, such as a ROM / RAM, a magnetic disk, an optical disk, and the like, and includes a plurality of instructions for causing a computer device (which can be a personal computer, a mobile terminal, a server, or a network device, etc.) to execute the methods described in the embodiments of the present application.

[0099] The various embodiments in the specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referred to each other. Each embodiment focuses on the difference from other embodiments. The whole or part of the present application can be used in a plurality of general or special computer system environments or configurations.

[0100] The above embodiments are only used to illustrate the technical solutions of the present application, and not to limit the present application; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacements for some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the present application.

Claims

1. A tilt six-rotor power system failure handling method, characterized in that, The method comprises the following steps: Real-time monitoring of the operating components involved in the power system, collecting core data and analyzing and processing to determine the fault type of the power system; Determine the power coefficient of the power system under the current fault type, establish the control matrix after failure, and establish a new control distribution matrix based on the control matrix after failure; Based on the fault type and the new control distribution matrix, as well as the number of power system failures and the power state, different control and response strategies are adopted for the unmanned aerial vehicle.

2. The tilting hexacopter power system failure handling method of claim 1, wherein, The fault type includes power system power supply shortage, power system overload, power system failure, tilt nacelle jamming, tilt actuator feedback failure, total distance control failure, rotor partial failure and rotor failure; The power system power supply shortage is determined by low output voltage; The power system overload is determined by the simultaneous occurrence of low output voltage, large power system current and high output power; The power system failure is determined by the simultaneous occurrence of low rotor speed, low output power and high motor temperature; The tilt nacelle jamming is determined by the inconsistency between the tilt actuator feedback value and the command value; The tilt actuator feedback failure is determined by the tilt actuator state feedback failure; The total distance control failure is determined by the total distance actuator state feedback failure; The rotor partial failure is determined by the simultaneous occurrence of low output power and low rotor speed; The rotor failure is determined by the rotor speed state feedback failure.

3. The tilting six-rotor power system failure handling method of claim 1, wherein, The method for determining the power coefficient of the power system under the current fault type, establishing the control matrix after failure, and establishing a new control distribution matrix based on the control matrix after failure comprises: Apply the power coefficient of the power system under the current fault type to the corresponding elements of the original control matrix of the power system to obtain the control matrix after failure; based on obtaining a new control distribution matrix; wherein is the original control matrix, is the control distribution matrix, is the virtual control quantity of the four control channels, is the control matrix after failure, is the new control distribution matrix; Control the unmanned aerial vehicle based on the control matrix after failure and the new control distribution matrix.

4. The tilting hexacopter power system failure handling method of claim 1 or 3, wherein, The original control matrix includes the rotor total distance control matrix and the aerodynamic rudder and throttle control matrix, and the control distribution matrix includes the rotor total distance control distribution matrix and the aerodynamic rudder and throttle control distribution matrix. The method for determining the power coefficient of the power system under the current fault type, establishing the control matrix after failure, and establishing a new control distribution matrix based on the control matrix after failure comprises: Apply the power coefficient of the power system under the current fault type to the corresponding elements of the rotor total distance control matrix of the power system to obtain the rotor total distance control matrix after failure; based on obtaining a failed rotor collective control matrix; wherein, is a rotor collective control matrix, is a rotor collective control allocation matrix, is a failed rotor collective control matrix, is a new rotor collective control allocation matrix, is a rotor tilt angle; Control the unmanned aerial vehicle based on the control matrix after failure, the new control distribution matrix, the aerodynamic rudder and throttle control matrix, and the aerodynamic rudder and throttle control distribution matrix.

5. The tilting six-rotor power system failure handling method of claim 1, wherein, The method for adopting different control and response strategies for the unmanned aerial vehicle based on the fault type and the new control distribution matrix, as well as the number of power system failures and the power state, comprises: In the case of single power system failure or partial failure, the control distribution matrix is reset to ensure normal flight of the unmanned aerial vehicle; And / or when two power systems fail or partially fail at the same time, the control distribution matrix is reset and a control strategy is developed to complete the landing; And / or if the power is insufficient during flight of the unmanned aerial vehicle, a transition mode is adopted to allow the flight altitude to be lowered.

6. The tilting hexacopter power system failure handling method of claim 5, wherein, The two power systems simultaneously fail or simultaneously partially fail, which is divided into no additional power failure, power partial failure, power large failure and attitude partial failure; The control strategy in the case of no additional power failure includes: in the case of two sets of diagonal rotors failing, the control allocation matrix is reset to ensure complete attitude control, so that the UAV returns normally and lands; The control strategy in the case of power partial failure includes: in the case of non-diagonal rotors and two rotors at different longitudinal positions failing simultaneously, the control allocation matrix is reset to ensure complete attitude control, and the fixed-wing mode is preferentially selected to make the UAV return normally; if in the transition mode, the flight speed is preferentially ensured when the height allows, the flight height is allowed to be reduced during the transition mode flight, and the UAV is controlled to slowly glide in the forced landing area after switching to the helicopter mode to complete the forced landing; The control strategy in the case of power large failure includes: in the case of rotors at the same longitudinal position failing, the control allocation matrix is reset to ensure complete attitude control, and the fixed-wing mode is preferentially selected to make the UAV return normally; if in the helicopter mode, the flight speed is preferentially ensured when the height allows, and the UAV is controlled to slowly glide in the forced landing area to complete the forced landing; The control strategy in the case of attitude partial failure includes: in the case of two sets of rotors on the wings failing, the roll angle and pitch angle control are preferentially ensured during flight, the yaw angle is stabilized by the vertical tail, and the remaining four power systems provide sufficient power to make the UAV return in the fixed-wing mode, complete the transition and land.

7. The tilting hexacopter power system failure handling method of claim 6, wherein, If the UAV has insufficient power during flight, a transition mode allowing the flight height to be reduced is adopted, which includes: The tension is increased to the maximum when the attitude of the UAV is stable; During the transition from the fixed-wing mode to the helicopter mode, the pitch angle is adjusted to convert the gravitational potential energy into kinetic energy to maintain the flight speed; The lift restriction is removed, and a constraint condition is set; the constraint condition relates to the balance relationship among the rotor tension, resistance and gravitational component; the gravitational component is related to the pitch angle; The constraint condition includes: the pitch angle command value is related to the lift rate; when the UAV starts to enter the transition mode, the relative height is greater than a preset threshold, indicating that the airspeed is greater than the minimum speed boundary determined by the transition corridor.

8. A tilting hexacopter power system failure handling device, comprising: It includes: A monitoring module for real-time monitoring of the operating components involved in the power system, collecting core data and performing analysis and processing to determine the fault type of the power system; A building module for determining the power coefficient of the power system under the current fault type, establishing a control matrix after failure, and establishing a new control allocation matrix based on the control matrix after failure; A control module for taking different control and response strategies for the UAV based on the fault type and the new control allocation matrix, as well as the number of power system failures and the power state.

9. A tilt six-rotor power system failure handling server, characterized in that, It includes a memory and a processor; The memory is used to store computer executable instructions; The processor is used to execute the computer executable instructions to realize the method of any one of claims 1-7.

10. A computer-readable storage medium, characterized in that, The computer readable storage medium stores executable instructions, and the computer executes the executable instructions to implement the method in any one of claims 1-7.

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