A flight control method suitable for a single-rotor micro unmanned aerial vehicle

Abstract

The application relates to a flight control method suitable for a single-rotor micro unmanned plane, a state, a feedback state and a flight control physical parameter combination are received through a remote control link to form a link state label, link fluctuation is associated with a single-rotor power margin and a tail rotor compensation margin, and mode switching is avoided by only relying on communication abnormalities; a label exchange pair is formed by the link state label and a current flight control mode label, manual control, attitude keeping, autonomous hovering and safe landing have clear switching bases; the label exchange pair is used to determine a control quantity transition sequence, tail rotor compensation and main rotor power connection are preferentially processed, and yaw mutation caused by counter torque imbalance is reduced; flight control instructions are generated by each transition quantity, and attitude continuity and flight stability in the link fluctuation and link recovery process are improved.

Description

Technical Field

[0001] This invention belongs to the field of UAV flight control and aircraft attitude control technology, specifically a flight control method applicable to single-rotor micro UAVs. Background Technology

[0002] With the increasing application of micro-drones in scenarios such as low-altitude inspection, reconnaissance in confined spaces, equipment movement, emergency monitoring, and close-range operations, flight control technology is gradually evolving from single-attitude stabilization control to link status awareness, mode switching control, and actuator collaborative control. Compared to multi-rotor micro-drones, single-rotor micro-drones typically rely on their main rotor to generate lift and use a tail rotor or tail actuator to counteract the main rotor's anti-torque. Their flight attitude is strongly coupled with main rotor power, tail rotor compensation, roll control, and pitch control. When the remote control link is stable, the flight controller can generate relatively continuous control quantities based on remote control input, attitude feedback, and power feedback. However, under conditions of indoor obstruction, complex electromagnetic environments, unauthorized spectrum interference, metal component reflection, or long-distance low-altitude flight, the reception and feedback states of the remote control link are prone to fluctuations, causing changes in the control command arrival interval, control command sequence number offset, acknowledgment information return interval, and telemetry signal amplitude. In existing flight control technologies, the handling of link anomalies mostly adopts strategies such as returning to home after losing contact, hovering at a fixed point, emergency landing, or maintaining the previous control variable. Although such strategies can reduce the risk of UAV loss of control to a certain extent, they focus more on whether the link is interrupted and do not fully combine the main rotor power margin, tail rotor compensation margin, and attitude actuator response characteristics of single-rotor micro UAVs.

[0003] Existing flight control methods for single-rotor micro UAVs still have the following shortcomings: First, there is a lack of clear intermediate state expression between link status judgment and flight control mode switching. Hovering, return to home, or landing are usually triggered directly based on packet loss, loss of connection, or signal weakening, which can easily lead to abrupt switching between manual control, attitude maintenance, autonomous hovering, and safe landing. Second, during weak links or link recovery, there may be delay differences between external remote control inputs and local flight control quantities. If manual control is directly restored, it is easy to cause abrupt changes in tail rotor compensation, abrupt changes in main rotor power, and discontinuities in roll and pitch control quantities. Third, single-rotor micro UAVs have high requirements for the coordination between tail rotor compensation and main rotor power. If the tail rotor compensation and anti-torque balance relationship is not prioritized when switching flight control modes, it may cause yaw drift, airframe oscillation, or altitude disturbance. Fourth, existing technologies mostly process communication link status and flight control physical status separately, lacking a control mechanism that combines remote control link receiving status, return status, and flight control physical parameters into a unified link status label, and then establishes a label exchange pair based on the link status label and the current flight control mode label. Therefore, existing technologies struggle to balance the smoothness of flight control mode switching, the continuity of single-rotor power compensation, and the stability of flight control command execution in scenarios involving link fluctuations, weak links, and link recovery.

[0004] In summary, existing single-rotor micro UAV flight control technologies suffer from problems such as disconnect between link status identification and flight control mode switching, discontinuous control quantity transitions under weak link conditions, and abrupt changes in flight control commands during link recovery. This invention addresses this issue by combining remote control link reception status, feedback status, and flight control physical parameters to form a link status tag. Based on the link status tag and the current flight control mode tag, a target flight control mode tag is determined. Then, through tag exchange, the control quantity transition sequence is determined, sequentially generating tail rotor compensation transition, main rotor power transition, roll transition, and pitch transition. This solves the problem of smooth flight control transition during link fluctuations and mode switching in single-rotor micro UAVs. Summary of the Invention

[0005] The purpose of this section is to outline some aspects of embodiments of the present invention and to briefly describe some preferred embodiments. Simplifications or omissions may be made in this section, as well as in the abstract and title of this application, to avoid obscuring the purpose of these documents; however, such simplifications or omissions should not be construed as limiting the scope of the invention.

[0006] To solve the above-mentioned technical problems, the present invention provides the following technical solution: As a preferred technical solution of the flight control method for single-rotor micro UAVs described in this invention, a link status tag is formed based on the combination of remote control link receiving status, transmission status and flight control physical parameters; The target flight control mode label is determined based on the link status label and the current flight control mode label, and a label exchange pair is formed by the current flight control mode label and the target flight control mode label; The control quantity transition sequence is determined according to the tag exchange pair, and the tail rotor compensation transition, main rotor power transition, roll transition and pitch transition are generated sequentially according to the control quantity transition sequence. Flight control commands for a single-rotor micro-UAV are generated based on the tail rotor compensation transition amount, the main rotor power transition amount, the roll transition amount, and the pitch transition amount.

[0007] The beneficial effects of this invention are as follows: This invention forms a link status tag by combining the remote control link receiving status, return status, and flight control physical parameters, thus establishing a correlation between link fluctuations and single-rotor power margin and tail rotor compensation margin, avoiding mode switching triggered solely by communication anomalies; a tag exchange pair is formed by the link status tag and the current flight control mode tag, providing a clear basis for switching between manual control, attitude maintenance, autonomous hovering, and safe landing; the tag exchange pair determines the control quantity transition order, prioritizing the connection between tail rotor compensation and main rotor power, reducing yaw abrupt changes caused by anti-torque imbalance; and flight control commands are generated through each transition quantity, improving attitude continuity and flight stability during link fluctuations and link recovery processes. Attached Figure Description

[0008] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. Wherein: Figure 1 This is a schematic flowchart of the flight control method for a single-rotor micro unmanned aerial vehicle (UAV) according to the present invention. Detailed Implementation

[0009] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0010] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the spirit of the invention. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0011] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it a single or selective embodiment that is mutually exclusive with other embodiments.

[0012] Secondly, the present invention is described in detail with reference to the schematic diagrams. When detailing the embodiments of the present invention, for ease of explanation, the cross-sectional views illustrating the device structure may be partially enlarged, not according to the usual scale. Furthermore, the schematic diagrams are merely examples and should not limit the scope of protection of the present invention. In addition, actual fabrication should include three-dimensional spatial dimensions of length, width, and depth.

[0013] This embodiment provides a flight control method suitable for a single-rotor micro-UAV. The single-rotor micro-UAV includes a flight controller, a remote control receiving module, a telemetry feedback module, a main rotor motor, a tail rotor servo, a roll servo, a pitch servo, an attitude sensor, a battery voltage sampling circuit, and a motor speed sampling circuit. The flight controller has a flight control cycle of 20ms. The remote control receiving module receives control commands sent by the remote controller in each flight control cycle. The telemetry feedback module returns confirmation information and telemetry information to the remote controller in each flight control cycle. The attitude sensor collects roll angle, pitch angle, yaw angle, roll rate, and pitch rate. The motor speed sampling circuit collects the main rotor motor speed, and the battery voltage sampling circuit collects the battery terminal voltage. The flight controller forms a link status tag based on the remote control link reception status, the feedback status, and the flight control physical parameters, and performs segmented transition processing on the control quantities during flight control mode switching based on the link status tag.

[0014] According to an embodiment of the present invention, in combination Figure 1 The flowchart shown illustrates a flight control method for a single-rotor micro unmanned aerial vehicle (UAV), which specifically includes the following steps: S1. A link status tag is formed based on the combination of remote control link reception status, transmission status, and flight control physical parameters. Note that the following points should be noted in this step: S1.1 Merge the control command arrival interval, control command sequence number offset, and received signal amplitude in the remote control link receiving status to form a receiving status group.

[0015] In S1.1, the remote control link receiving state is the receiving-side state formed when the remote control receiving module receives remote control commands within the same flight control cycle. The remote control link receiving state includes the control command arrival interval, the control command sequence number offset, and the received signal amplitude. The control command arrival interval is the time interval between the arrival time of the control command received in the current flight control cycle and the arrival time of the control command received in the previous flight control cycle. The control command sequence number offset is the consecutive numbering offset result of the currently received control command sequence number relative to the previously confirmed control command sequence number. When the current control command sequence number continuously increases by 1 relative to the previously confirmed control command sequence number, the control command sequence number offset is 0. When there are skipped numbers, duplicate numbers, or backtracking numbers, the control command sequence number offset is the corresponding non-zero value. The received signal amplitude is the received signal strength value measured by the remote control receiving module when the control command reception is completed, in dBm.

[0016] The control command arrival interval is obtained as follows: after the remote control receiving module completes the control command frame verification, the flight controller obtains the arrival time of the control command frame and calculates the time difference between this arrival time and the arrival time of the previously received control command frame to obtain the control command arrival interval. The control command sequence number offset is obtained as follows: the control command frame includes a control command sequence number, and the flight controller compares the current control command sequence number with the previously confirmed control command sequence number to obtain the control command sequence number offset. The received signal amplitude is obtained as follows: the remote control receiving module outputs a received signal strength sample value at the end of the control command frame reception, and the flight controller uses this received signal strength sample value as the received signal amplitude. Preferably, when the flight control cycle is 20ms, the control command arrival interval is between 18ms and 22ms, the control command sequence number offset is 0, and the received signal amplitude is not lower than -82dBm, the remote control link reception status can be used as a continuous reception status to participate in the generation of subsequent link status tags.

[0017] The method for merging the receiving status groups is as follows: the flight controller combines the control command arrival interval, control command sequence number offset, and received signal amplitude obtained within the same flight control cycle in a fixed order, namely, control command arrival interval, control command sequence number offset, and received signal amplitude. The structure of the receiving status group includes a control cycle identifier, a control command arrival interval position, a control command sequence number offset position, and a received signal amplitude position. For example, in the 1250th flight control cycle, if the control command arrival interval is 20ms, the control command sequence number offset is 0, and the received signal amplitude is -68dBm, then the resulting receiving status group is the receiving status group corresponding to the 1250th flight control cycle, and this receiving status group sequentially contains the control command arrival interval of 20ms, the control command sequence number offset of 0, and the received signal amplitude of -68dBm.

[0018] S1.2 Merge the acknowledgment information return interval, acknowledgment information sequence number offset, and telemetry signal amplitude in the backhaul status to form a backhaul status group.

[0019] In S1.2, the feedback state refers to the feedback-side state formed when the telemetry feedback module returns confirmation information and telemetry information to the remote controller within the same flight control cycle. The feedback state includes the confirmation information return interval, the confirmation information sequence number offset, and the telemetry signal amplitude. The confirmation information return interval is the time interval between the current confirmation information return time and the previous confirmation information return time; the confirmation information sequence number offset is the corresponding offset result of the current confirmation information sequence number relative to the current control command sequence number. When the current confirmation information sequence number is the same as the current control command sequence number, the confirmation information sequence number offset is 0; when the current confirmation information sequence number lags behind or precedes the current control command sequence number, the confirmation information sequence number offset is the corresponding non-zero value; the telemetry signal amplitude is the received confirmation signal strength returned by the remote controller after the telemetry feedback module sends telemetry information, in dBm.

[0020] The confirmation information return interval is obtained as follows: after the telemetry feedback module completes the transmission of the confirmation information, the flight controller obtains the return time of the confirmation information and calculates the time difference between the return time and the return time of the previous confirmation information to obtain the confirmation information return interval. The confirmation information sequence number offset is obtained as follows: the confirmation information includes a confirmation sequence number corresponding to the control command sequence number. The flight controller compares the confirmation sequence number with the current control command sequence number to obtain the confirmation information sequence number offset. The telemetry signal amplitude is obtained as follows: after receiving the telemetry information, the remote controller generates a reception confirmation signal. The telemetry feedback module receives the reception confirmation signal and uses the signal strength sample value of the reception confirmation signal as the telemetry signal amplitude. Preferably, when the flight control cycle is 20ms, the confirmation information return interval is between 18ms and 24ms, the confirmation information sequence number offset is 0, and the telemetry signal amplitude is not lower than -85dBm, the feedback state can be used as a continuous feedback state to participate in the generation of subsequent link status tags.

[0021] The method for merging the feedback status groups is as follows: the flight controller combines the confirmation information return interval, the confirmation information sequence number offset, and the telemetry signal amplitude obtained within the same flight control cycle in a fixed order, namely, confirmation information return interval, confirmation information sequence number offset, and telemetry signal amplitude. The structure of the feedback status group includes a control cycle identifier, a confirmation information return interval position, a confirmation information sequence number offset position, and a telemetry signal amplitude position. For example, in the 1250th flight control cycle, if the confirmation information return interval is 21ms, the confirmation information sequence number offset is 0, and the telemetry signal amplitude is -72dBm, then the resulting feedback status group is the feedback status group corresponding to the 1250th flight control cycle, and this feedback status group sequentially contains the confirmation information return interval of 21ms, the confirmation information sequence number offset of 0, and the telemetry signal amplitude of -72dBm.

[0022] S1.3 Align the receiving status group, the return status group, and the flight control physical parameter combination according to the same flight control cycle to form a link flight control association group.

[0023] In S1.3, the flight control physical parameter combination includes tail rotor compensation margin, main rotor power margin, roll rate, pitch rate, fuselage tilt angle, and battery terminal voltage. The tail rotor compensation margin is the remaining ratio between the current increase in tail rotor servo deflection and the maximum allowable deflection of the tail rotor servo. The main rotor power margin is the remaining ratio between the current increase in duty cycle of the main rotor motor and the maximum allowable duty cycle of the main rotor motor. The roll rate and pitch rate are output by attitude sensors, the fuselage tilt angle is determined by the roll and pitch angles from the attitude sensors, and the battery terminal voltage is output by a battery voltage sampling circuit. Preferably, the tail rotor compensation margin and the main rotor power margin are expressed as a percentage, the units for the roll rate and pitch rate are ° / s, the unit for the fuselage tilt angle is °, and the unit for the battery terminal voltage is V.

[0024] The method for obtaining the flight control physical parameter combination is as follows: after the start of each flight control cycle, the flight controller obtains the attitude sampling value output by the attitude sensor, the main rotor speed sampling value output by the motor speed sampling circuit, the battery terminal voltage sampling value output by the battery voltage sampling circuit, and the current position feedback value of the servo; the tail rotor compensation margin is obtained based on the current position feedback value of the tail rotor servo and the allowable deflection boundary of the tail rotor servo; the main rotor power margin is obtained based on the current duty cycle of the main rotor motor and the maximum allowable duty cycle of the main rotor motor; the tail rotor compensation margin, the main rotor power margin, the roll rate, the pitch rate, the fuselage tilt angle, and the battery terminal voltage are combined in a fixed order to form the flight control physical parameter combination.

[0025] The method for aligning the receiving state group, the feedback state group, and the flight control physical parameter combination according to the same flight control cycle is as follows: The flight control controller uses the start time of the flight control cycle as the cycle reference, and classifies the receiving state group, the feedback state group, and the flight control physical parameter combination formed within that flight control cycle into the same control cycle identifier; when the receiving state group, the feedback state group, and the flight control physical parameter combination all correspond to the same control cycle identifier, the three are combined in the order of receiving state group, feedback state group, and flight control physical parameter combination to form the link flight control association group. The structure of the link flight control association group includes the control cycle identifier, the position of the receiving state group, the position of the feedback state group, and the position of the flight control physical parameter combination. For example, if the cycle length of the 1250th flight control cycle is 20ms, and the receiving state group, the feedback state group, and the flight control physical parameter combination are formed within this cycle, then the link flight control association group is the link flight control association group corresponding to the 1250th flight control cycle.

[0026] S1.4. Based on the correspondence between the control command sequence number offset, confirmation information sequence number offset, tail rotor compensation margin, and main rotor power margin in the link flight control association group, a link status label is formed; wherein, the link status label includes a stable link label, a fluctuating link label, a weak link label, and a recovering link label.

[0027] Specifically, the correspondence includes: forming a stable link label when both the control command sequence number offset and the confirmation information sequence number offset are within a continuous numbering interval, and both the tail rotor compensation margin and the main rotor power margin are within the flight control holding interval; forming a fluctuating link label when either the control command sequence number offset or the confirmation information sequence number offset deviates from the continuous numbering interval, and both the tail rotor compensation margin and the main rotor power margin are within the flight control holding interval; forming a weak link label when both the control command sequence number offset and the confirmation information sequence number offset deviate from the continuous numbering interval, and both the tail rotor compensation margin and the main rotor power margin deviate from the flight control holding interval; and forming a recovery link label when the link status label in the previous flight control cycle was the weak link label or the fluctuating link label, and the control command sequence number offset and the confirmation information sequence number offset in the current flight control cycle return to the continuous numbering interval, and both the tail rotor compensation margin and the main rotor power margin return to the flight control holding interval.

[0028] In S1.4, the consecutive numbering interval is the control command sequence number offset 0 and the confirmation information sequence number offset 0. The flight control holding interval includes a tail rotor compensation margin of not less than 15%, a main rotor power margin of not less than 18%, a fuselage tilt angle of not more than 18°, a roll rate of not more than 90° / s, a pitch rate of not more than 90° / s, and a battery terminal voltage of not less than 3.5V. The flight controller extracts the control command sequence number offset, the confirmation information sequence number offset, the tail rotor compensation margin, and the main rotor power margin from the link flight control association group, and forms the link status label according to the correspondence between the above parameters.

[0029] A stable link label is formed when the control command number offset is 0, the confirmation information number offset is 0, and both the tail rotor compensation margin and the main rotor power margin are within the flight control holding range. A fluctuating link label is formed when either the control command number offset or the confirmation information number offset is non-zero, and both the tail rotor compensation margin and the main rotor power margin are within the flight control holding range. A weak link label is formed when both the control command number offset and the confirmation information number offset are non-zero, and either the tail rotor compensation margin or the main rotor power margin deviates from the flight control holding range. A recovering link label is formed when the link status label of the previous flight control cycle was a weak link label or a fluctuating link label, the control command number offset of the current flight control cycle is 0, the confirmation information number offset is 0, and both the tail rotor compensation margin and the main rotor power margin have returned to the flight control holding range.

[0030] Step S1 associates the remote control receiving status, the feedback confirmation status, and the airframe physical margin within the same flight control cycle, enabling the flight controller to distinguish between simple communication fluctuations, communication weakening accompanied by insufficient airframe margin, and the link recovery phase. This step addresses the issue that single-rotor micro-UAVs easily overlook tail rotor compensation margin and main rotor power margin when switching modes solely based on remote control signal strength. It ensures that subsequent flight control mode determination has a shared basis in both communication and flight physical states, reducing the risk of yaw jitter, sudden main rotor power fluctuations, and attitude disturbances caused by sudden switching under weak link conditions.

[0031] S2. Determine the target flight control mode label based on the link status label and the current flight control mode label, and form a label exchange pair with the current flight control mode label and the target flight control mode label. It should be noted that in this step: S2.1 Combine the link status label and the current flight control mode label according to the same flight control cycle to form a mode determination label group.

[0032] Specifically, forming the mode determination tag group includes: acquiring the link status tag formed within the same flight control cycle and the current flight control mode tag currently executed by the flight controller; placing the link status tag in the link status bit and the current flight control mode tag in the flight control mode bit to form a tag combination unit; associating the tag combination unit with the control cycle identifier of the flight control cycle to form the mode determination tag group.

[0033] In S2.1, the current flight control mode label is the flight control mode marker that the flight control controller is executing at the beginning of the current flight control cycle. The current flight control mode label includes a manual control label, an attitude hold label, an autonomous hover label, and a safe landing label. The current flight control mode label is obtained as follows: after the start of each flight control cycle, the flight control controller retrieves the currently executing flight control mode marker from its flight control mode status register unit and uses this flight control mode marker as the current flight control mode label. The link status label is obtained as follows: the flight control controller retrieves the link status label formed in step S1 within the same flight control cycle and combines this link status label with the current flight control mode label.

[0034] The link status bit is the position in the mode determination tag group that carries the link status tag. The link status bit can carry one of the following: stable link tag, fluctuating link tag, weak link tag, and recovery link tag. The flight control mode bit is the position in the mode determination tag group that carries the current flight control mode tag. The flight control mode bit can carry one of the following: manual control tag, attitude hold tag, autonomous hovering tag, and safe landing tag. The control cycle identifier is a cycle number formed by the flight control controller incrementing according to the flight control cycle. Preferably, the control cycle identifier increments once every one flight control cycle.

[0035] The tag combination unit is formed as follows: the flight controller places the link status tag formed within the same flight control cycle into the link status position, and places the current flight control mode tag into the flight control mode position, maintaining the link status position first and the flight control mode position second, thus forming the tag combination unit. The mode determination tag group is formed as follows: the flight controller associates the tag combination unit with the control cycle identifier of the same flight control cycle, thus forming the mode determination tag group. The structure of the mode determination tag group includes a control cycle identifier, a link status position, and a flight control mode position. For example, in the 1250th flight control cycle, if the link status tag is a fluctuating link tag and the current flight control mode tag is a manual control tag, then the formed mode determination tag group includes the control cycle identifier of the 1250th flight control cycle, the fluctuating link tag, and the manual control tag.

[0036] S2.2 When the mode determination tag group includes a stable link tag and the current flight control mode tag is a manual control tag, then the target flight control mode tag is the manual control tag.

[0037] S2.3 When the mode determination tag group includes a fluctuation link tag, the target flight control mode tag is an attitude maintenance tag.

[0038] S2.4 When the mode determination tag group includes a weak link tag and the flight control physical parameter combination is in the flight control holding range, the target flight control mode tag is an autonomous hovering tag.

[0039] S2.5 When the mode determination tag group includes the weak link tag, and the flight control physical parameter combination deviates from the flight control holding range, then the target flight control mode tag is a safe landing tag.

[0040] S2.6 When the mode determination tag group includes the recovery link tag, the target flight control mode tag is the attitude maintenance tag.

[0041] In steps S2.2 to S2.6, the flight controller determines the target flight control mode label based on the mode determination label group. Preferably, when the mode determination label group includes a stable link label and the current flight control mode label is a manual control label, the target flight control mode label is the manual control label; when the mode determination label group includes a fluctuating link label, the target flight control mode label is an attitude hold label; when the mode determination label group includes a weak link label and the flight control physical parameter combination is within the flight control hold range, the target flight control mode label is an autonomous hover label; when the mode determination label group includes a weak link label and the flight control physical parameter combination deviates from the flight control hold range, the target flight control mode label is a safe landing label; and when the mode determination label group includes a recovering link label, the target flight control mode label is the attitude hold label.

[0042] The flight control holding range is obtained as follows: During the model calibration phase, the flight controller obtains the tail rotor servo deflection range, main rotor motor duty cycle range, attitude angular velocity range, fuselage tilt angle range, and battery terminal voltage safety range for a single-rotor micro-UAV in low-speed level flight, hovering, and low-speed turning states. The range from which no sustained flight attitude deviation occurs is selected as the flight control holding range. Preferably, the flight control holding range includes a tail rotor compensation margin of not less than 15%, a main rotor power margin of not less than 18%, a roll rate not greater than 90° / s, a pitch rate not greater than 90° / s, a fuselage tilt angle not greater than 18°, and a battery terminal voltage not less than 3.5V. For a single-rotor micro-UAV with a main rotor diameter of 180mm and a total weight of 95g, the above flight control holding range can cover the normal control margin in indoor hovering, low-speed forward flight, and low-speed lateral movement states.

[0043] The rule for determining whether the flight control physical parameter combination deviates from the flight control holding range is as follows: The flight control controller compares the tail rotor compensation margin, main rotor power margin, roll rate, pitch rate, fuselage tilt angle, and battery terminal voltage in the flight control physical parameter combination with the flight control holding range item by item; when the tail rotor compensation margin is less than 15%, or the main rotor power margin is less than 18%, or the roll rate is greater than 90° / s, or the pitch rate is greater than 90° / s, or the fuselage tilt angle is greater than 18°, or the battery terminal voltage is less than 3.5V, the flight control physical parameter combination is determined to deviate from the flight control holding range; when all of the above parameters are within the corresponding value range, the flight control physical parameter combination is determined to be within the flight control holding range.

[0044] S2.7. The current flight control mode label and the target flight control mode label are combined into a label exchange pair according to the order of switching.

[0045] Specifically, the step of forming tag exchange pairs according to the order of switching includes: S2.7.1. Set the current flight control mode label to the switching start position and the target flight control mode label to the switching reach position to form a mode switching unit; S2.7.2. Place the link status label in the mode determination label group into the link constraint bit of the mode switching unit to form a link mode association unit; S2.7.3. Determine the mode switching order according to the link mode association unit; when the link constraint bit is the stable link label, the mode switching order is the switching start bit and the switching to reach bit in sequence; when the link constraint bit is the fluctuating link label, the weak link label or the recovery link label, the mode switching order is the switching start bit, the attitude maintenance label and the switching to reach bit in sequence. S2.7.4. Combine the link constraint bit, the handover start bit, the handover arrival bit, and the mode switching sequence to form a label switching pair.

[0046] In S2.7, the flight controller places the current flight control mode label in the switching start position and the target flight control mode label in the switching arrival position, forming a mode switching unit; it places the link status label from the mode determination label group into the link constraint bit of the mode switching unit, forming a link mode association unit; and it determines the mode switching order based on the link mode association unit. The link constraint bit is the position in the label exchange pair carrying the link status label, the switching start position is the position in the label exchange pair carrying the current flight control mode label, the switching arrival position is the position in the label exchange pair carrying the target flight control mode label, and the mode switching order is the label arrangement order used when switching from the current flight control mode label to the target flight control mode label.

[0047] When the link constraint bit is the stable link label, the mode switching order is the switching start bit followed by the switching to reach bit in sequence. When the link constraint bit is the fluctuating link label, the weak link label, or the recovery link label, the mode switching order is the switching start bit, the attitude maintenance label, and the switching to reach bit in sequence. The flight controller combines the link constraint bit, the switching start bit, the switching to reach bit, and the mode switching order to form the label exchange pair. For example, if the current flight control mode label is the manual control label, the link status label is the weak link label, and the flight control physical parameter combination is within the flight control maintenance range, the target flight control mode label is the autonomous hovering label. The label exchange pair includes the weak link label, the manual control label, the autonomous hovering label, and the mode switching order of the manual control label, attitude maintenance label, and autonomous hovering label in sequence.

[0048] Step S2 determines the flight control mode switching within the same flight control cycle by combining the link status label and the current flight control mode label. An attitude maintenance label is introduced as an intermediate transition label under the fluctuating link label, weak link label, and recovering link label. This step solves the problem of abrupt control variable changes when a single-rotor micro-UAV switches directly from manual control to autonomous hovering or safe landing during link fluctuation or recovery phases. It ensures that the target flight control mode label and the combination of flight control physical parameters remain consistent, reducing the risk of yaw mismatch and sudden altitude drop under weak link conditions.

[0049] S3. Determine the control quantity transition sequence based on the tag exchange pair, and generate the tail rotor compensation transition, main rotor power transition, roll transition, and pitch transition in sequence according to the control quantity transition sequence. Note that the following should be noted in this step: S3.1 Extract the link constraint bit, the handover start bit, the handover arrival bit, and the mode switching sequence from the label switching pair.

[0050] In S3.1, the flight controller extracts the link constraint bit, the handover start bit, the handover arrival bit, and the mode switching sequence from the tag exchange pair. The extraction method is as follows: the flight controller sequentially obtains the first, second, third, and fourth tag positions according to a fixed arrangement in the tag exchange pair, where the first tag position corresponds to the link constraint bit, the second tag position corresponds to the handover start bit, the third tag position corresponds to the handover arrival bit, and the fourth tag position corresponds to the mode switching sequence. Through this arrangement, the flight controller can determine the control quantity transition sequence within the same flight control cycle.

[0051] S3.2 When the mode switching sequence includes the attitude holding label, the transition order of the control quantities is the order of tail rotor compensation quantity, main rotor dynamic force, roll control quantity, and pitch control quantity.

[0052] S3.3 When the mode switching sequence does not include the attitude holding label, the transition order of the control quantities is the order of main rotor dynamics, tail rotor compensation, roll control, and pitch control.

[0053] S3.4. According to the control quantity transition sequence, the control quantity under the switching start position and the control quantity under the switching to the arrival position are transitioned in segments to generate the tail rotor compensation transition quantity, the main rotor power transition quantity, the roll transition quantity and the pitch transition quantity in sequence.

[0054] Specifically, the segmented transition includes: S3.4.1. Based on the control quantity transition sequence, extract the initial tail rotor compensation quantity, initial main rotor dynamic force, initial roll control quantity, and initial pitch control quantity from the switching start position. S3.4.2 According to the control quantity transition sequence, switch from the position extraction to the tail rotor compensation quantity, the main rotor dynamic force, the roll control quantity, and the pitch control quantity. S3.4.3. Connect the initial tail rotor compensation amount and the final tail rotor compensation amount in segments according to the control quantity transition sequence to generate the tail rotor compensation transition amount. S3.4.4 After the tail rotor compensation transition amount is generated, the initial main rotor dynamic force and the arriving main rotor dynamic force are segmented and connected according to the control amount transition sequence to generate the main rotor dynamic transition amount. S3.4.5 After the main rotor power transition amount is generated, the initial roll control amount and the arrival roll control amount are segmented and connected according to the control amount transition sequence to generate the roll transition amount. S3.4.6 After the roll transition amount is generated, the initial pitch control amount and the arrival pitch control amount are segmented and connected according to the transition sequence of the control amounts to generate the pitch transition amount.

[0055] In S3.4.1, the flight controller obtains the initial tail rotor compensation, initial main rotor dynamics, initial roll control, and initial pitch control from the flight control mode control table corresponding to the switching start position, according to the control quantity transition sequence. The flight control mode control table is a set of control quantities formed by the flight controller for each actuator within the current flight control cycle. This set of control quantities includes the tail rotor compensation, main rotor dynamics, roll control, and pitch control. Preferably, the tail rotor compensation is represented by a microsecond offset relative to the center pulse width of the tail rotor servo; the main rotor dynamics is represented by a duty cycle increment relative to the lower limit of the main rotor motor throttle; the roll control is represented by a microsecond offset relative to the center pulse width of the roll servo; and the pitch control is represented by a microsecond offset relative to the center pulse width of the pitch servo.

[0056] For example, when the switching start position is the manual control tag, the starting tail rotor compensation amount formed by the flight controller based on the remote control input in the current flight control cycle is +60μs, the starting main rotor dynamic force is 36%, the starting roll control amount is -30μs, and the starting pitch control amount is +25μs. Then, the above four control amounts constitute the set of starting control amounts under the switching start position.

[0057] In S3.4.2, the flight controller obtains the arrival tail rotor compensation, arrival main rotor power, arrival roll control, and arrival pitch control from the flight control mode control table corresponding to the arrival position, according to the control quantity transition sequence. The flight control mode control table corresponding to the arrival position is determined by the target flight control mode label. When the target flight control mode label is the attitude hold label, the arrival control quantity set is generated based on the current attitude angle deviation, current angular velocity, and current main rotor speed; when the target flight control mode label is the autonomous hover label, the arrival control quantity set is generated based on the current attitude angle deviation, altitude change, and main rotor speed change; when the target flight control mode label is the safe landing label, the arrival control quantity set is generated based on the landing direction, main rotor power reduction magnitude, and airframe attitude convergence direction.

[0058] For example, when switching to the autonomous hovering tag, the flight controller, based on the current roll angle of 2°, pitch angle of -3°, altitude change of 0.15m, and main rotor speed change of 180r / min, sets the arrival tail rotor compensation amount to +20μs, the arrival main rotor dynamic force to 32%, the arrival roll control amount to +10μs, and the arrival pitch control amount to -15μs. These four control amounts constitute the set of arrival control amounts under the switch to arrival tag.

[0059] In S3.4.3 to S3.4.6, the segmented connection rule is as follows: the flight controller, based on the transition sequence of the control quantity, divides the value of the same control quantity under the switching start position and the value under the switching to the arrival position into an initial hold segment, an intermediate change segment, and an arrival hold segment. The initial hold segment occupies 2 flight control cycles, the intermediate change segment occupies 6 flight control cycles, and the arrival hold segment occupies 2 flight control cycles. The initial hold segment uses the control quantity under the switching start position, the intermediate change segment transitions from the initial control quantity to the arrival control quantity in an arithmetic progression manner between adjacent flight control cycles, and the arrival hold segment uses the control quantity under the switching to the arrival position. The above three segments are connected sequentially to form corresponding transition quantities.

[0060] The segmented connection rule for the tail rotor compensation transition amount is as follows: when the control quantity transition sequence includes an attitude hold label, the initial tail rotor compensation amount and the arriving tail rotor compensation amount are first segmented and connected to form the tail rotor compensation transition amount; within the intermediate transition segment, the tail rotor compensation change amount in adjacent flight control cycles is no greater than 20 μs. Taking the aforementioned example, the initial tail rotor compensation amount is +60 μs, the arriving tail rotor compensation amount is +20 μs, and the intermediate transition segment occupies 6 flight control cycles. Therefore, the tail rotor compensation transition amount approaches +20 μs sequentially within the 6 flight control cycles, and the change amount in a single flight control cycle does not exceed 20 μs, thereby reducing yaw oscillation caused by sudden changes in tail rotor servo deflection.

[0061] The segmented transition rule for the main rotor power transition is as follows: after the tail rotor compensation transition is generated, the flight controller segments the initial main rotor power and the arriving main rotor power to form the main rotor power transition; within the intermediate transition segment, the change in main rotor power in adjacent flight control cycles is no greater than 3%. Taking the aforementioned example, the initial main rotor power is 36%, the arriving main rotor power is 32%, and the main rotor power transition changes from 36% to 32% within 6 flight control cycles, with the duty cycle change in each flight control cycle not exceeding 3%, thereby reducing the impact of sudden changes in main rotor lift on the aircraft altitude.

[0062] The segmented transition rule for the roll transition is as follows: after the main rotor power transition is generated, the flight controller segments the initial roll control quantity and the arrival roll control quantity to form the roll transition quantity; within the intermediate transition segment, the roll control change between adjacent flight control cycles is no greater than 15μs. Taking the aforementioned example, the initial roll control quantity is -30μs, the arrival roll control quantity is +10μs, and the roll transition quantity transitions from -30μs to +10μs within 6 flight control cycles, gradually changing the roll servo deflection direction within the intermediate transition segment to reduce abrupt jumps in the roll channel.

[0063] The segmented transition rule for the pitch transition is as follows: after the roll transition is generated, the flight controller segments the initial pitch control and the arrival pitch control to form the pitch transition; within the intermediate transition segment, the pitch control change between adjacent flight control cycles is no greater than 15 μs. Taking the aforementioned example, the initial pitch control is +25 μs, the arrival pitch control is -15 μs, and the pitch transition transition changes from +25 μs to -15 μs within 6 flight control cycles, gradually changing the pitch servo deflection direction within the intermediate transition segment to reduce abrupt jumps in the pitch channel.

[0064] When the mode switching sequence includes the attitude hold label, the control quantity transition order is tail rotor compensation, main rotor dynamics, roll control, and pitch control. This order prioritizes the tail rotor compensation, which has a significant impact on yaw stability for single-rotor micro-UAVs, then processes the main rotor dynamics that determine lift, followed by roll and pitch control. When the mode switching sequence does not include the attitude hold label, the control quantity transition order is main rotor dynamics, tail rotor compensation, roll control, and pitch. This order is suitable for direct mode switching under the stabilization link label, ensuring that the main rotor dynamics first aligns with the target mode, and then the tail rotor compensation corrects the yaw direction.

[0065] Step S3 determines the transition sequence of control quantities through the tag exchange and segments and connects the tail rotor compensation quantity, main rotor dynamic force, roll control quantity, and pitch control quantity, so that the flight control mode switching is transformed from tag changes to continuous changes in the control quantities of the actuators. This step solves the problem of abrupt changes in control quantities during communication fluctuations, weak links, and link recovery phases of single-rotor micro UAVs. It can reduce the impact of instantaneous tail rotor servo deflection, sudden changes in main rotor motor duty cycle, and reverse jumps of roll and pitch servos on the airframe attitude, and improve flight stability during mode switching.

[0066] S4. Based on the tail rotor compensation transition amount, the main rotor power transition amount, the roll transition amount, and the pitch transition amount, generate flight control commands for the single-rotor micro-UAV. It should be noted that in this step: S4.1. According to the drive interface type of the single-rotor micro UAV flight controller, convert the tail rotor compensation transition amount into tail rotor servo control command, convert the main rotor power transition amount into main rotor motor control command, convert the roll transition amount into roll servo control command, and convert the pitch transition amount into pitch servo control command.

[0067] Specifically, the control command conversion according to the drive interface type of the single-rotor micro UAV flight controller includes: The tail rotor compensation transition amount is superimposed with the tail rotor servo mid-position pulse width, and the tail rotor servo deflection direction is determined according to the positive and negative directions of the tail rotor compensation transition amount to form the tail rotor servo pulse width amount. The tail rotor servo control command is generated according to the tail rotor servo pulse width amount. The main rotor power transition amount is superimposed with the lower limit of the main rotor motor throttle, and the main rotor motor speed direction is determined according to the increase or decrease direction of the main rotor power transition amount to form the main rotor motor duty cycle. The main rotor motor control command is generated according to the main rotor motor duty cycle. The roll transition amount is superimposed with the roll servo midpoint pulse width, and the roll servo deflection direction is determined according to the positive and negative directions of the roll transition amount to form the roll servo pulse width amount. The roll servo control command is generated based on the roll servo pulse width amount. The pitch transition amount is superimposed with the pitch servo's mid-range pulse width, and the pitch servo's deflection direction is determined according to the positive and negative directions of the pitch transition amount to form the pitch servo pulse width amount. The pitch servo control command is then generated based on the pitch servo pulse width amount.

[0068] In S4.1, the drive interface types of the single-rotor micro UAV flight controller include PWM servo drive interface, PWM ESC drive interface, serial ESC drive interface, and attitude servo drive interface. The tail rotor servo control commands, roll servo control commands, and pitch servo control commands are preferably output using the PWM servo drive interface, and the main rotor motor control commands are preferably output using either the PWM ESC drive interface or the serial ESC drive interface. Preferably, the median pulse width of the tail rotor servo is 1500 μs, the median pulse width of the roll servo is 1500 μs, the median pulse width of the pitch servo is 1500 μs, and the allowable range of the servo pulse width is 1000 μs to 2000 μs; the lower limit of the main rotor motor throttle is 8%, and the allowable range of the main rotor motor duty cycle is 8% to 85%.

[0069] The method for generating the tail rotor servo control command is as follows: the flight controller adds the tail rotor compensation transition amount to the tail rotor servo's neutral pulse width to obtain the tail rotor servo pulse width; when the tail rotor compensation transition amount is positive, the tail rotor servo deflection direction is the right yaw compensation direction; when the tail rotor compensation transition amount is negative, the tail rotor servo deflection direction is the left yaw compensation direction; when the tail rotor compensation transition amount is 0 μs, the tail rotor servo remains in the neutral position. The flight controller limits the tail rotor servo pulse width to within 1000 μs to 2000 μs and generates the tail rotor servo control command according to the pulse width output format of the PWM servo drive interface. For example, if the tail rotor compensation transition amount is +40μs and the tail rotor servo mid-range pulse width is 1500μs, then the tail rotor servo pulse width is 1540μs, and the tail rotor servo control command is a PWM control command with a pulse width of 1540μs and a direction of right yaw compensation.

[0070] The method for generating the main rotor motor control commands is as follows: the flight controller adds the main rotor power transition amount to the lower limit of the main rotor motor throttle to obtain the main rotor motor duty cycle; when the main rotor power transition amount increases relative to the previous flight control cycle, the main rotor motor speed direction is the acceleration direction; when the main rotor power transition amount decreases relative to the previous flight control cycle, the main rotor motor speed direction is the deceleration direction; when the main rotor power transition amount remains unchanged relative to the previous flight control cycle, the main rotor motor speed direction is the current speed maintenance direction. The flight controller limits the main rotor motor duty cycle to between 8% and 85% and generates the main rotor motor control commands according to the duty cycle output format of the PWM ESC drive interface or the serial ESC drive interface. For example, if the main rotor power transition amount is 32% and the main rotor motor throttle lower limit is 8%, then the main rotor motor duty cycle is 40%. When the main rotor motor duty cycle of the previous flight control cycle is 42%, the main rotor motor control command is a motor control command with a duty cycle of 40% and a deceleration direction.

[0071] The method for generating the roll servo control command is as follows: The flight controller adds the roll transition amount to the median pulse width of the roll servo to obtain the roll servo pulse width. When the roll transition amount is positive, the roll servo deflects in the right roll correction direction; when the roll transition amount is negative, the roll servo deflects in the left roll correction direction; when the roll transition amount is 0 μs, the roll servo remains in the median position. The flight controller limits the roll servo pulse width to between 1000 μs and 2000 μs and generates the roll servo control command according to the pulse width output format of the PWM servo drive interface. For example, if the roll transition amount is +10 μs and the median pulse width of the roll servo is 1500 μs, then the roll servo pulse width is 1510 μs, and the roll servo control command is a PWM control command with a pulse width of 1510 μs and a direction of right roll correction.

[0072] The method for generating the pitch servo control command is as follows: The flight controller adds the pitch transition amount to the pitch servo's center pulse width to obtain the pitch servo pulse width. When the pitch transition amount is positive, the pitch servo yaws in the direction of nose-up correction; when the pitch transition amount is negative, the pitch servo yaws in the direction of nose-down correction; when the pitch transition amount is 0 μs, the pitch servo remains in the center position. The flight controller limits the pitch servo pulse width to between 1000 μs and 2000 μs and generates the pitch servo control command according to the pulse width output format of the PWM servo drive interface. For example, if the pitch transition amount is -15 μs and the pitch servo's center pulse width is 1500 μs, then the pitch servo pulse width is 1485 μs, and the pitch servo control command is a PWM control command with a pulse width of 1485 μs and a direction of nose-down correction.

[0073] In a specific application scenario, a single-rotor micro-UAV flies forward at 0.6 m / s in an indoor inspection channel, with a flight control cycle of 20 ms. During the 1250th flight control cycle, the remote control receiving module receives control commands at an interval of 31 ms, with a control command sequence number offset of 2 and a received signal amplitude of -89 dBm; the telemetry feedback module receives confirmation information at an interval of 35 ms, with a confirmation information sequence number offset of 1 and a telemetry signal amplitude of -91 dBm; the attitude sensor outputs a body tilt angle of 12°, a roll rate of 48° / s, and a pitch rate of 52° / s; the tail rotor compensation margin is 22%, the main rotor power margin is 24%, and the battery terminal voltage is 3.72V. At this time, both the control command sequence number offset and the confirmation information sequence number offset deviate from the continuous numbering interval, but the flight control physical parameter combination is within the flight control holding interval. Therefore, step S1 forms a weak link label, and step S2 determines the target flight control mode label as an autonomous hovering label, and forms a mode switching sequence arranged in the order of manual control label, attitude holding label, and autonomous hovering label.

[0074] In the specific application scenario described above, the initial tail rotor compensation amount under the switching start position is +60μs, the initial main rotor power is 36%, the initial roll control amount is -30μs, and the initial pitch control amount is +25μs; the arrival tail rotor compensation amount under the switching to the arrival position is +20μs, the arrival main rotor power is 32%, the arrival roll control amount is +10μs, and the arrival pitch control amount is -15μs. Step S3 forms the tail rotor compensation transition amount, the main rotor power transition amount, the roll transition amount, and the pitch transition amount respectively according to the control amount transition sequence of the tail rotor compensation amount, the main rotor power transition amount, the roll transition amount, and the pitch transition amount. In the 1256th flight control cycle, the tail rotor compensation transition amount is +40μs, the main rotor power transition amount is 32%, the roll transition amount is +10μs, and the pitch transition amount is -15μs. Step S4 converts the above transition values ​​into tail rotor servo control commands, main rotor motor control commands, roll servo control commands, and pitch servo control commands, wherein the tail rotor servo control command is 1540 μs, the main rotor motor control command is 40%, the roll servo control command is 1510 μs, and the pitch servo control command is 1485 μs.

[0075] S4.2 Arrange the tail rotor servo control commands, the main rotor motor control commands, the roll servo control commands, and the pitch servo control commands in the order of the control quantities to form a command arrangement group; S4.3 When the target flight control mode label is the manual control label, the tail rotor servo control command, the main rotor motor control command, the roll servo control command and the pitch servo control command in the command arrangement group are arranged according to the remote control input direction to form a manual flight control command; S4.4 When the target flight control mode label is an attitude holding label or an autonomous hovering label, the tail rotor servo control command, the main rotor motor control command, the roll servo control command and the pitch servo control command in the command arrangement group are arranged in the attitude holding direction to form an attitude holding flight control command or an autonomous hovering flight control command. S4.5 When the target flight control mode label is the safe landing label, the tail rotor servo control command, the main rotor motor control command, the roll servo control command and the pitch servo control command in the command arrangement group are arranged according to the landing direction to form a safe landing flight control command.

[0076] In S4.2 to S4.5, the flight controller arranges the tail rotor servo control commands, main rotor motor control commands, roll servo control commands, and pitch servo control commands according to the transition order of the control quantities, forming a command arrangement group. When the target flight control mode label is the manual control label, the flight controller arranges each control command in the command arrangement group according to the remote control input direction, forming a manual flight control command; when the target flight control mode label is the attitude hold label or the autonomous hover label, the flight controller arranges each control command in the command arrangement group according to the attitude hold direction, forming an attitude hold flight control command or an autonomous hover flight control command; when the target flight control mode label is the safe landing label, the flight controller arranges each control command in the command arrangement group according to the landing direction, forming a safe landing flight control command. The landing direction includes the main rotor motor duty cycle gradually decreasing according to the flight control cycle, the roll and pitch servos correcting towards the horizontal attitude of the aircraft, and the tail rotor servo correcting towards the direction of decreasing yaw rate.

[0077] Step S4 converts the tail rotor compensation transition amount, the main rotor power transition amount, the roll transition amount, and the pitch transition amount into drive commands that the corresponding actuators can receive. This ensures that the continuous transition results formed in step S3 directly correspond to the actual control inputs of the tail rotor servo, main rotor motor, roll servo, and pitch servo. This step resolves the issue of unclear conversion between the mode switching transition amount and the drive interface of the flight control actuators. It ensures that the control commands in weak link, autonomous hovering, and safe landing scenarios have clear pulse width, duty cycle, and deflection direction, thereby improving the controllability and landing safety of single-rotor micro UAVs under remote control link fluctuation conditions.

[0078] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A flight control method suitable for single-rotor micro unmanned aerial vehicles, characterized in that, include: A link status tag is formed based on the combination of remote control link reception status, transmission status, and flight control physical parameters. The target flight control mode label is determined based on the link status label and the current flight control mode label, and a label exchange pair is formed by the current flight control mode label and the target flight control mode label; The control quantity transition sequence is determined according to the tag exchange pair, and the tail rotor compensation transition, main rotor power transition, roll transition and pitch transition are generated sequentially according to the control quantity transition sequence. Flight control commands for a single-rotor micro-UAV are generated based on the tail rotor compensation transition amount, the main rotor power transition amount, the roll transition amount, and the pitch transition amount.

2. The flight control method for a single-rotor micro unmanned aerial vehicle according to claim 1, characterized in that, Forming the link status label includes: The control command arrival interval, control command sequence number offset, and received signal amplitude in the remote control link reception status are merged to form a reception status group; The acknowledgment information return interval, acknowledgment information sequence number offset, and telemetry signal amplitude in the backhaul status are merged to form a backhaul status group; The receiving status group, the return status group, and the flight control physical parameter combination are aligned according to the same flight control cycle to form a link flight control association group; Based on the correspondence between the control command sequence number offset, confirmation information sequence number offset, tail rotor compensation margin, and main rotor power margin in the link flight control association group, a link status label is formed. The link status labels include stable link labels, fluctuating link labels, weak link labels, and recovering link labels.

3. The flight control method for a single-rotor micro-UAV according to claim 2, characterized in that, The correspondence includes: When both the control command sequence number offset and the confirmation information sequence number offset are within a consecutive numbering range, and both the tail rotor compensation margin and the main rotor power margin are within the flight control holding range, a stable link tag is formed. When the control command sequence number offset or the confirmation information sequence number offset deviates from the continuous numbering interval, and the tail rotor compensation margin and the main rotor power margin are both within the flight control holding interval, a fluctuation link tag is formed. When both the control command sequence number offset and the confirmation information sequence number offset deviate from the consecutive numbering interval, and the tail rotor compensation margin or the main rotor power margin deviates from the flight control holding interval, a weak link label is formed. If the link status label in the previous flight control cycle was the weak link label or the fluctuating link label, and the control command sequence number offset and the confirmation information sequence number offset in the current flight control cycle return to the continuous numbering interval, and the tail rotor compensation margin and the main rotor power margin return to the flight control holding interval, then a recovery link label is formed.

4. The flight control method for a single-rotor micro-UAV according to claim 1, characterized in that, Forming the tag exchange pair includes: The link status label and the current flight control mode label are combined according to the same flight control cycle to form a mode determination label group; When the mode determination tag group includes a stable link tag and the current flight control mode tag is a manual control tag, then the target flight control mode tag is the manual control tag; When the mode determination tag group includes a fluctuation link tag, the target flight control mode tag is an attitude maintenance tag; When the mode determination tag group includes a weak link tag and the flight control physical parameter combination is in the flight control holding range, the target flight control mode tag is an autonomous hovering tag. When the mode determination tag group includes the weak link tag, and the flight control physical parameter combination deviates from the flight control holding range, then the target flight control mode tag is a safe landing tag; When the mode determination tag group includes the recovery link tag, the target flight control mode tag is the attitude maintenance tag; The current flight control mode label and the target flight control mode label are paired according to the order of switching.

5. The flight control method for a single-rotor micro-UAV according to claim 4, characterized in that, Forming the pattern determination tag group includes: Obtain the link status tag formed within the same flight control cycle and the current flight control mode tag currently executed by the flight control controller; place the link status tag in the link status bit and the current flight control mode tag in the flight control mode bit to form a tag combination unit; associate the tag combination unit with the control cycle identifier of the flight control cycle to form the mode determination tag group.

6. The flight control method for a single-rotor micro unmanned aerial vehicle according to claim 4, characterized in that, The tag exchange pairs formed according to the order of switching include: The current flight control mode label is set to the switching start position, and the target flight control mode label is set to the switching reach position, thus forming a mode switching unit; The link status label in the mode determination label group is placed into the link constraint bit of the mode switching unit to form a link mode association unit; The mode switching order is determined according to the link mode association unit; when the link constraint bit is the stable link label, the mode switching order is the switching start bit and the switching to reach bit in sequence; when the link constraint bit is the fluctuating link label, the weak link label, or the recovery link label, the mode switching order is the switching start bit, the attitude maintenance label, and the switching to reach bit in sequence. The link constraint bit, the handover start bit, the handover arrival bit, and the mode switching bit are combined in sequence to form a label switching pair.

7. The flight control method for a single-rotor micro-UAV according to claim 6, characterized in that, The tail rotor compensation transition, main rotor power transition, roll transition, and pitch transition are generated sequentially according to the control quantity transition order, including: Extract the link constraint bit, the handover start bit, the handover arrival bit, and the mode switching sequence from the label switching pair; When the mode switching sequence includes the attitude hold label, the control quantity transition order is the order of tail rotor compensation quantity, main rotor dynamic force, roll control quantity, and pitch control quantity. When the mode switching sequence does not include the attitude holding label, the control quantity transition order is the order of main rotor dynamics, tail rotor compensation, roll control, and pitch control. According to the control quantity transition sequence, the control quantity under the switching start position and the control quantity under the switching to the arrival position are transitioned in segments to generate the tail rotor compensation transition quantity, the main rotor power transition quantity, the roll transition quantity and the pitch transition quantity in sequence.

8. The flight control method for a single-rotor micro unmanned aerial vehicle according to claim 7, characterized in that, The segmented transition includes: Based on the control quantity transition sequence, the initial tail rotor compensation quantity, initial main rotor dynamic force, initial roll control quantity, and initial pitch control quantity are extracted from the switching start position. According to the control quantity transition sequence, the switch is made from reaching the tail rotor compensation quantity, reaching the main rotor dynamic force, reaching the roll control quantity, and reaching the pitch control quantity. The initial tail rotor compensation amount and the arriving tail rotor compensation amount are segmented and connected according to the control quantity transition sequence to generate the tail rotor compensation transition amount. After the tail rotor compensation transition amount is generated, the initial main rotor dynamic force and the arriving main rotor dynamic force are segmented and connected according to the control amount transition sequence to generate the main rotor dynamic transition amount. After the main rotor power transition amount is generated, the initial roll control amount and the arrival roll control amount are segmented and connected according to the control amount transition sequence to generate the roll transition amount. After the roll transition amount is generated, the initial pitch control amount and the arrival pitch control amount are segmented and connected according to the transition sequence of the control amounts to generate the pitch transition amount.

9. The flight control method for a single-rotor micro unmanned aerial vehicle according to claim 1, characterized in that, Generating the flight control commands includes: According to the drive interface type of the single-rotor micro UAV flight controller, the tail rotor compensation transition amount is converted into a tail rotor servo control command, the main rotor power transition amount is converted into a main rotor motor control command, the roll transition amount is converted into a roll servo control command, and the pitch transition amount is converted into a pitch servo control command. The tail rotor servo control commands, the main rotor motor control commands, the roll servo control commands, and the pitch servo control commands are arranged in the order of the control quantities to form a command arrangement group; When the target flight control mode label is manual control, the tail rotor servo control command, the main rotor motor control command, the roll servo control command and the pitch servo control command in the command arrangement group are arranged according to the remote control input direction to form a manual flight control command; When the target flight control mode label is an attitude hold label or an autonomous hover label, the tail rotor servo control command, the main rotor motor control command, the roll servo control command and the pitch servo control command in the command arrangement group are arranged in the attitude hold direction to form an attitude hold flight control command or an autonomous hover flight control command. When the target flight control mode label is the safe landing label, the tail rotor servo control command, the main rotor motor control command, the roll servo control command, and the pitch servo control command in the command arrangement group are arranged according to the landing direction to form a safe landing flight control command.

10. The flight control method for a single-rotor micro unmanned aerial vehicle according to claim 9, characterized in that, The control command conversion according to the drive interface type of the single-rotor micro UAV flight controller includes: The tail rotor compensation transition amount is superimposed with the tail rotor servo mid-position pulse width, and the tail rotor servo deflection direction is determined according to the positive and negative directions of the tail rotor compensation transition amount to form the tail rotor servo pulse width amount. The tail rotor servo control command is generated according to the tail rotor servo pulse width amount. The main rotor power transition amount is superimposed with the lower limit of the main rotor motor throttle, and the main rotor motor speed direction is determined according to the increase or decrease direction of the main rotor power transition amount to form the main rotor motor duty cycle. The main rotor motor control command is generated according to the main rotor motor duty cycle. The roll transition amount is superimposed with the roll servo midpoint pulse width, and the roll servo deflection direction is determined according to the positive and negative directions of the roll transition amount to form the roll servo pulse width amount. The roll servo control command is generated based on the roll servo pulse width amount. The pitch transition amount is superimposed with the pitch servo's mid-range pulse width, and the pitch servo's deflection direction is determined according to the positive and negative directions of the pitch transition amount to form the pitch servo pulse width amount. The pitch servo control command is then generated based on the pitch servo pulse width amount.

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