Variable body rotorcraft near wall control method and system for tight spaces

Abstract

The present disclosure provides a variable fuselage rotorcraft near-wall control method and system suitable for narrow space, relating to the technical field of aircraft flight control, comprising: obtaining aircraft deformation parameters and flight state data; estimating internal disturbance channel low-frequency bias torque and external disturbance channel high-frequency aerodynamic disturbance; generating a target command vector according to the desired attitude and the two disturbance estimation values, and obtaining the control amount of each propulsion controller based on the WLS priority control allocation of the effective set method; during the flight process of controlling the aircraft deformation, the lift attenuation caused by the mutual shielding of the rotors during the deformation process is dealt with, the independent thrust model is updated based on the offline wind tunnel calibration shielding package angle, and the target rotating speed is improved, the slit passing and aerodynamic feedforward adaptive compensation are realized, and the aircraft is restored to the unfolded configuration after passing through the slit. The present disclosure can inhibit the risk of rollover caused by actuator saturation in the extreme contraction or severe rotor overlap working condition, and improve the passing ability in narrow space.

Description

Technical Field

[0001] This disclosure relates to the field of aircraft flight control technology, specifically to a near-wall control method and system for variable-flying rotorcraft applicable to confined spaces. Background Technology

[0002] The statements in this section are merely background information relating to this disclosure and do not necessarily constitute prior art.

[0003] In missions such as disaster search and rescue, industrial pipeline inspection, narrow shaft detection, and detailed inspection of building facades, aircraft often need to pass through narrow gaps smaller than their nominal wingspan or wheelbase and fly stably in environments close to walls, ceilings, or pipe interiors. Traditional rigid quadcopters typically rely on reducing the overall size of the aircraft to improve its maneuverability, but this reduction in size simultaneously weakens payload capacity, endurance, and interference immunity, making it difficult to balance maneuverability and operational performance.

[0004] Existing deformable aircraft designs mainly include folding arm designs driven by multiple independent actuators, unidirectional folding or spring-loaded locking designs oriented towards launch and storage, scissor or linkage designs with single-axis extension and retraction but not integrated with the main load-bearing fuselage, and control designs that only compensate for static center of gravity shifts under normal conditions. However, these existing designs still have the following limitations: (1) It often only solves one of the problems in structural deformation, storage and deployment or conventional disturbance resistance, and is difficult to adapt to the complex working conditions in which narrow space crossing and near-wall flight occur at the same time.

[0005] (2) In confined space scenarios, aircraft will not only experience changes in center of gravity and inertia due to changes in body geometry, but also suffer lift loss due to close-range rotor overlap, and be subject to asymmetric aerodynamic forces and aerodynamic torque disturbances caused by wall effects when flying near walls. Existing solutions do not integrate the design of multimodal deformation, main load-bearing stiffness, near-wall stability and actuator anti-saturation, making it difficult to stably achieve narrow passage and wall-hugging operations in complex tasks. Summary of the Invention

[0006] To address the aforementioned issues, this disclosure proposes a near-wall control method and system for variable-fuselage rotorcraft suitable for confined spaces. This method enables multi-configuration deformation of the aircraft without excessively increasing the number of independent actuators, allowing the deformation mechanism to directly constitute the main load-bearing structure of the fuselage. When fuselage deformation and near-wall flight occur simultaneously, it estimates and compensates for internal low-frequency offset torque and external high-frequency aerodynamic disturbances separately. Furthermore, it suppresses actuator saturation by controlling and allocating priority, thereby reducing the risk of rollover and crash.

[0007] According to some embodiments, the present disclosure adopts the following technical solutions: Near-wall control methods for variable-flying rotorcraft applicable to confined spaces include: The deformation parameters and flight status data of the aircraft are obtained, and the deformation parameters are reconstructed based on the principle of superposition of a particle system. The low-frequency bias torque of the internal disturbance rejection channel is estimated using a second-order continuous-time extended state observer, and the high-frequency aerodynamic disturbance of the external disturbance rejection channel is estimated based on flight state data. The target command vector is generated based on the desired attitude and two disturbance estimates. The objective function for propulsion control quantity allocation is constructed, and the control quantity of each propulsion controller is obtained by using WLS priority control allocation based on the effective set method. During the controlled flight of the aircraft in deformation mode, the lift attenuation caused by mutual shielding of the rotors during deformation is addressed. The independent thrust model is updated based on the shielding envelope angle calibrated in the offline wind tunnel, and the target rotation speed is increased to achieve adaptive compensation for slit crossing and aerodynamic feedforward. After passing through the slit, the aircraft returns to its deployed configuration.

[0008] According to some embodiments, the present disclosure adopts the following technical solutions: A variable-fuselage rotorcraft includes a central fuselage, a forward deformable module, a rear deformable module, four propulsion units, a sensing component, and a flight controller. The forward deformable module adjusts the position of the two front propulsion units relative to the central fuselage, and the rear deformable module adjusts the position of the two rear propulsion units relative to the central fuselage. The forward and rear deformable modules can be controlled independently, thereby allowing the aircraft to switch between a standard deployed configuration, a fully retracted configuration, a first asymmetric slit configuration, and a forward unobstructed wall-hugging configuration.

[0009] Furthermore, the front deformation module and the rear deformation module are arranged sequentially along the longitudinal direction of the central fuselage; each deformation module includes a drive component, a bidirectional threaded screw, two sliding nuts on the left and right, at least one pair of guide rails, and a guide rail-constrained scissor linkage mechanism connected to the sliding nuts; each deformation module is driven by a drive source to rotate the bidirectional threaded screw, and the left and right sections of the bidirectional threaded screw are respectively provided with threads with opposite directions of rotation and the same or matched leads, so that the two sliding nuts on the left and right move towards the center or unfold to both sides synchronously.

[0010] According to some embodiments, the present disclosure adopts the following technical solutions: A near-wall control system for variable-flight rotorcraft suitable for confined spaces, including: The data acquisition module is used to acquire the deformation parameters and flight status data of the aircraft, and the deformation parameters are reconstructed based on the principle of superposition of a particle system. The disturbance estimation module is used to estimate the low-frequency bias torque of the internal disturbance rejection channel using a second-order continuous-time extended state observer, and to estimate the high-frequency aerodynamic disturbance of the external disturbance rejection channel based on flight state data. The propulsion allocation module is used to generate a target command vector based on the desired attitude and two disturbance estimates, construct a propulsion control quantity allocation objective function, and use WLS priority control allocation based on the effective set method to obtain the control quantity of each propulsion controller. The flight control module is used to control the aircraft during its deformable flight, to deal with the lift attenuation caused by mutual occlusion of the rotors during the deformable process, to update the independent thrust model based on the occlusion envelope angle calibrated in the offline wind tunnel, and to increase the target rotation speed, so as to achieve adaptive compensation for slit crossing and aerodynamic feedforward, and to restore the aircraft to its deployed configuration after passing through the slit.

[0011] According to some embodiments, the present disclosure adopts the following technical solutions: A computer program product includes a computer program that, when executed by a processor, implements the near-wall control method for a variable-fly rotorcraft suitable for confined spaces.

[0012] According to some embodiments, the present disclosure adopts the following technical solutions: A non-transitory computer-readable storage medium is provided for storing computer instructions, which, when executed by a processor, implement the near-wall control method for a variable-fly rotorcraft suitable for confined spaces.

[0013] According to some embodiments, the present disclosure adopts the following technical solutions: An electronic device includes a processor, a memory, and a computer program; wherein the processor is connected to the memory, the computer program is stored in the memory, and when the electronic device is running, the processor executes the computer program stored in the memory to enable the electronic device to perform the near-wall control method for a variable-fly rotorcraft suitable for narrow spaces.

[0014] Compared with the prior art, the beneficial effects of this disclosure are as follows: This disclosed near-wall control method for variable-flying rotorcraft applicable to confined spaces reduces asymmetric deformation and attitude deviations, trajectory errors, and oscillation amplitudes during near-wall flight by separately estimating and compensating for internal low-frequency bias torque and external high-frequency near-wall aerodynamic disturbance torque, thereby improving near-wall operational stability. Through form-dependent control performance updates and a priority-based WLS control allocation strategy, it can suppress the risk of rollover caused by actuator saturation under conditions of extreme contraction or severe rotor overlap, and prioritize the protection of total thrust, roll, and pitch channels when control margin is insufficient.

[0015] This disclosed method for near-wall control of variable-flying rotorcraft applicable to confined spaces reduces the proportion of forward field-of-view obstruction by coordinating a forward-facing unobstructed wall-hugging configuration with forward-mounted sensing components, thereby improving the effective sensing field of view in wall-hugging detection, near-wall modeling, and facade inspection scenarios. Through a slit-crossing feedforward compensation mechanism, the target rotational speed can be increased in advance when effective thrust decreases due to fuselage contraction and rotor obstruction, reducing the risk of altitude loss and attitude divergence during crossing.

[0016] The variable-flying rotorcraft disclosed herein, suitable for narrow spaces, uses an independent morphing module set at the front and rear, and adopts a single-drive symmetrical motion scheme within each module. Compared with the multi-independent servo folding arm scheme, it can reduce the number of actuators, reduce the complexity of the mechanism and wiring harness, and facilitate the lightweight design of the whole machine.

[0017] The variable-fuselage rotorcraft disclosed herein, suitable for narrow spaces, incorporates a rail-constrained scissor mechanism into the main load-bearing structure of the fuselage. In the deployed state, it can maintain good bending and torsional stiffness, and in the retracted state, it can reduce the risk of jamming and out-of-plane instability. Furthermore, when combined with a lead screw self-locking or anti-reverse drive design, it is beneficial to improve collision stability and configuration retention capability.

[0018] The variable-flying rotorcraft disclosed herein, suitable for narrow spaces, can change its envelope width, projected length, and envelope area in real time according to the size and shape of the slit through independent, continuous, and reversible configuration adjustment, thereby improving its ability to pass through narrow spaces and meeting both routine cruise and special operation requirements. Attached Figure Description

[0019] The accompanying drawings, which form part of this disclosure, are used to provide a further understanding of this disclosure. The illustrative embodiments of this disclosure and their descriptions are used to explain this disclosure and do not constitute an undue limitation of this disclosure.

[0020] Figure 1 This is a schematic diagram of the overall assembly structure of the aircraft according to an embodiment of the present disclosure; Figure 2 This is a schematic diagram of the structure of a single deformable module according to an embodiment of the present disclosure; Figure 3 These are schematic diagrams illustrating four typical configurations of embodiments of this disclosure; wherein, Figure 3 (a) in the diagram represents the standard expansion configuration; Figure 3 (b) in the diagram represents the fully contractile configuration; Figure 3 (c) in the diagram represents the first asymmetric narrow slit configuration; Figure 3 (d) in the diagram represents a forward-facing, unobstructed, wall-hugging configuration. This visually reflects the differences. , The dynamic envelope of the combined system shows that the standard deployed state has a large envelope size and control lever arm; the fully retracted state has a small lateral passage size but a large rotor obstruction; and the projection ratio relationship of the first asymmetric slit configuration and the forward unobstructed wall-hugging configuration is shown.

[0021] Figure 4 This is a control block diagram of the flight control method according to an embodiment of the present disclosure; Figure 5 This is a schematic diagram of near-wall disturbance compensation according to an embodiment of the present disclosure; Figure 6 This is a schematic diagram illustrating the control allocation priority switching of an embodiment of the present disclosure; Figure 7 The slit diagram provided in this disclosure illustrates the process of an aircraft approaching the slit, initiating deformation, passing through the slit, feeding forward to compensate for the target rotation speed, and resuming deployment.

[0022] The components include: 1. Central fuselage; 2. Forward deformable module; 3. Rear deformable module; 4. Drive unit; 5. Two-way threaded screw; 6. Sliding nut; 7. Guide rail; 8. Scissor linkage mechanism; 9. Propulsion unit; 10. Sensing components; and 11. Flight controller.

[0023] 5a. Left-hand thread portion; 5b. Right-hand thread portion. Detailed Implementation

[0024] The present disclosure will be further described below with reference to the accompanying drawings and embodiments.

[0025] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of this disclosure. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains.

[0026] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this disclosure. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms “comprising” and / or “including” are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0027] Example 1 One embodiment of this disclosure provides a near-wall control method for a variable-flying rotorcraft applicable to confined spaces, the method comprising the following steps: Step 1: Obtain the deformation parameters and flight status data of the aircraft, and reconstruct the deformation parameters based on the principle of superposition of a system of particles; Step 2: Use a second-order continuous-time extended state observer to estimate the low-frequency bias torque of the internal disturbance rejection channel, and estimate the high-frequency aerodynamic disturbance of the external disturbance rejection channel based on flight state data; Step 3: Generate the target command vector based on the desired attitude and two disturbance estimates, construct the objective function for propulsion control quantity allocation, and use WLS priority control allocation based on the effective set method to obtain the control quantity of each propulsion controller; Step 4: During the flight of the controlled aircraft in deformation mode, the lift attenuation caused by mutual shading of the rotors during deformation is addressed. The independent thrust model is updated based on the shading envelope angle calibrated in the offline wind tunnel, and the target rotation speed is increased to achieve adaptive compensation for slit crossing and aerodynamic feedforward. After passing through the slit, the aircraft returns to the deployed configuration.

[0028] As one embodiment, this disclosure proposes a variable-fuselage rotorcraft that achieves independent, reversible, and continuous multi-configuration deformation of the aircraft's front and rear without excessively increasing the number of independent actuators. Secondly, the deformation mechanism directly constitutes the main load-bearing structure of the fuselage, maintaining sufficient rigidity in the deployed state and being less prone to jamming, out-of-plane instability, or being driven by external forces in the retracted state. Specific details are as follows: like Figure 1 As shown, a variable-flyout rotorcraft includes a central fuselage 1, a forward morphing module 2, a rear morphing module 3, four propulsion units 9, a sensing component 10, and a flight controller 11. The forward morphing module 2 is used to adjust the position of the two forward propulsion units 9 relative to the central fuselage 1, and the rear morphing module 3 is used to adjust the position of the two rear propulsion units 9 relative to the central fuselage 1. The forward morphing module 2 and the rear morphing module 3 can be controlled independently, thereby allowing the aircraft to switch between a standard deployed configuration, a fully retracted configuration, a first asymmetric slit configuration, and a forward-facing unobstructed wall-hugging configuration.

[0029] Furthermore, the front and rear independent deformation modules: the front deformation module 2 and the rear deformation module 3 are arranged sequentially along the longitudinal direction of the fuselage. Each deformation module includes a drive component 4, a bidirectional threaded screw 5, two sliding nuts 6 on the left and right sides, at least one pair of guide rails 7, and a guide rail-constrained scissor linkage mechanism 8 connected to the sliding nuts 6. Each deformation module is driven by a drive source to rotate the bidirectional threaded screw 5. The left and right sections of the screw 5 are respectively provided with threads of opposite directions and the same or matched leads, so that the two sliding nuts 6 on the left and right sides synchronously move towards the center or unfold to both sides. At any time interval... The displacement of the sliding nut relative to its initial position. It can be calculated using formula (1): (1) in, The instantaneous speed of the servo motor driving the device. For the lead of a bidirectional threaded screw, For driving duration.

[0030] Furthermore, the central fuselage 1 serves as the origin of the reference coordinate system, bearing constant mass and inertia. The propulsion unit moves with the module, forming the physical entity of the time-varying vector in the model reconstruction formula. It is used to install the power battery, flight control motherboard, inertial measurement unit, attitude / position sensor, communication module, and necessary sensing components. Mounting bases are provided at the front and rear of the central fuselage 1, respectively, which are connected to the front deformable module 2 and the rear deformable module 3. The central fuselage 1 can be in the form of a composite material shell, a metal frame, or a combination of both.

[0031] Furthermore, each sliding nut 6 is connected to the proximal force-bearing node of the scissor linkage mechanism 8, and at least one cross hinge point of the scissor linkage mechanism 8 engages with a slider on the guide rail 7 to limit the deformation of the linkage mechanism primarily within the plane of the fuselage. Figure 2 As shown, the servo motor of the drive unit 4 drives the left and right sliding nuts 6 to make linear displacement through the bidirectional threaded screw 5, and the displacement is amplified by the scissor linkage mechanism 8 with anti-rotation constraint of the guide rail 7, driving the extension and retraction of the propulsion unit mounting base. This structure uses the scissor mechanism to amplify the displacement and the guide rail 7 to share the vertical and lateral loads, improving the bending and torsional resistance in the unfolded state and reducing the risk of jamming during high-speed deformation. The screw drive preferably has self-locking or semi-self-locking characteristics, or is equipped with a brake / clutch to suppress external force back drive. Its kinematic geometric mapping relationship can be expressed as formula (2): (2) in, For the first The lateral deployment coordinates of each propulsion unit For the number of scissor lift unit stages, The length of a single link. For the initial geometric bias, For deformation parameters, This represents the maximum lead screw travel.

[0032] Furthermore, each deformable module has a propulsion unit 9 mounting base at its output end. The propulsion unit 9 includes a motor, an ESC, and a propeller. To prevent rotor interference during retraction, adjacent propulsion units 9 can employ a staggered height, overlapping propeller disks for avoidance, or geometrically staggered blade design. The sensing component 10 preferably includes a camera, a depth sensor, a lidar, or a combination thereof; in a forward-facing unobstructed wall-hugging configuration, the proportion of arm and rotor obstruction within the forward field of view is reduced, thereby improving the effective field of view for wall-hugging detection and near-wall modeling.

[0033] As one embodiment, in the standard deployed configuration, both the front and rear deformable modules are in near-maximum deployed state, resulting in a large rotor spacing and control lever arm; in the fully retracted configuration, both the front and rear deformable modules are in near-minimum deployed state to reduce the lateral envelope width and longitudinal projection size; in the first asymmetric narrow slot configuration, the deformation parameters of the front and rear modules are unequal, causing the two pairs of rotor mounting points to form an asymmetric distribution; in the forward unobstructed wall-hugging configuration, by relatively retracting a group of propulsion units near the nose or tail and changing the arm obstruction relationship, the forward field of view obstruction ratio of the sensing component 10 is reduced. The lateral envelope width of the current configuration... Longitudinal projection length and envelope area All can be represented as , The folding rate, a function of , can be characterized by formula (3): (3) in, The envelope area under the standard unfolded configuration. This represents the projected envelope area under the current configuration.

[0034] As one embodiment, the near-wall control method for a variable-flying rotorcraft applicable to confined spaces disclosed herein revolves around "shape perception, parameter updating, dual-channel disturbance compensation, and priority control allocation," and the specific implementation process is as follows: S1: Multi-source morphological sensing and dynamic state acquisition. The displacement or normalized deformation parameters of the preceding and following deformation modules are obtained by the position detection component. , The position detection component includes one or more of the following: a rotary encoder mounted on a bidirectional threaded screw or drive component; a linear displacement sensor mounted on a sliding nut or guide rail slider; a Hall sensor; a photoelectric limit switch; or a motor feedback encoder. These components are used to acquire the actual displacement, screw rotation angle, or normalized deformation parameters of the front and rear deformation modules; and attitude quaternions are acquired by an IMU, visual inertial odometry, radar, or other sensing components. angular velocity ,speed ,Location and wall distance .

[0035] S2: Online reconstruction of time-varying rigid body parameters. The flight controller 11, based on the principle of superposition of mass systems, treats the central fuselage as a fixed reference rigid body and each arm / propulsion unit as a mass unit that moves with deformation parameters. Based on the real-time position vector of each mass unit in the body coordinate system, it calculates the overall center of gravity using a mass-weighted average. Then, using the parallel axis theorem, it translates the constant inertia of each component to the center of gravity and superimposes them to update the center of gravity position corresponding to the current configuration. Inertia matrix ( , and control effectiveness matrix ( , The formula for reconstructing the center of gravity due to drift can be expressed as formula (4): (4) in, Let be the vector of the aircraft's center of gravity position in the current deformed configuration. For the first The mass of each propulsion unit component ( , ) is the first Each propulsion unit component is subjected to deformation parameters in the body coordinate system. and The real-time position vector of the control, The total mass of the aircraft. To increase the total number of unit components.

[0036] Furthermore, the dynamic update formula for the inertia matrix is ​​shown in formula (5): (5) in, and The fuselage and the first The constant inertia tensor of each arm / propulsion unit component, The antisymmetric matrix operator for vectors.

[0037] S3: Low-frequency offset torque estimation for internal disturbance rejection channels. The low-frequency offset torque caused by asymmetric airframe deformation, changes in mass distribution, or rotor overlap lift variations is estimated using a second-order continuous-time extended state observer (ESO). Its state equation can be expressed as formula (6): ; (6) in, Used to approximate angular velocity , , Here is the observer gain matrix, in steady state... It converges to the low-frequency bias torque estimate.

[0038] S4: High-frequency aerodynamic disturbance estimation for the external disturbance rejection channel. Based on angular velocity, thrust residual, and wall distance. Estimate the high-frequency aerodynamic torque near the wall. The wall suction model based on the distance decay trigger threshold can be expressed as formula (7): (7) In the formula, The wall effect trigger threshold distance, This is the suction proportionality coefficient. Simultaneously, the high-frequency gust mutation term can be calculated using a fuzzy sliding mode observer, as shown in formula (8): (8) In the formula, For the approximation term of the fuzzy neural network, For angular velocity error, For sliding surface, For robust gain. The overall compensation can be written as: .

[0039] S5: Incremental nonlinear dynamic inverse INDI instruction generation. It calculates the attitude error based on the desired attitude and the current attitude, and the angular velocity error based on the desired angular velocity and the current angular velocity; the attitude controller outputs a reference angular acceleration or reference torque, which is then superimposed with the internal low-frequency offset torque compensation. Compensation for external high-frequency aerodynamic disturbances Generate target instruction vector = [ , , , ],in For the target total thrust, , , These are the target roll moment, pitch moment, and yaw moment, respectively. The underlying incremental control law can be expressed as formula (9): (9) in, , The aerodynamic moment mapping matrix, It is a low-pass filter operator. and This refers to the angular velocity and control increment in the previous sampling period or under the reference state.

[0040] S6: WLS priority control allocation based on the effective set method. Based on the control performance matrix... The target command is mapped to the control variables of each propulsion unit. The control allocation target functional can be expressed as formula (10): ,and (10) In the formula, For motor input or input increment, For the expected input, Given the input smoothing weight matrix, This is the task priority weight matrix. Priority scaling factor.

[0041] The effective set algorithm execution process includes: initializing the effective set and feasible solutions; solving for unconstrained control perturbations in the unsaturated motor column vectors; if the motor's physical limits are touched, calculating the interpolation coefficients and adding the motor to the saturated effective set; and when the saturation margin... When approaching 0, adaptively reduce The weighting of the yaw channel is prioritized to ensure total thrust, roll, and pitch channels.

[0042] S7: Slit crossing and aerodynamic feedforward adaptive compensation. When the controller detects that the size of the slit ahead is smaller than the current envelope size but larger than the minimum retractable envelope size, it initiates physical deformation at a preset trigger distance. To address the lift attenuation caused by rotor mutual obstruction during deformation, the obstruction angle calibrated offline in the wind tunnel can be used. Update the independent thrust model. The independent thrust model refers to establishing a thrust-speed relationship model for each propulsion unit separately, with the thrust under unobstructed conditions being... T i = k T · ω i ², in the occlusion state T i = k T · k i ( φ i )·ω i ², where k i ( φ i) To cover the corners φ i The corresponding effective thrust correction factor is obtained from offline wind tunnel tests or bench tests, and is determined based on the shielding angle under shielding conditions. Introducing effective thrust correction factor ( ), after correction = · ( ) · ,in ( The target rotational speed is obtained through offline wind tunnel testing or bench testing. The target rotational speed is increased in advance according to formula (11): , (11) In the formula, For the target thrust, The nominal thrust coefficient, For the first The rotor blades are shielding the corner. The effective thrust correction coefficient is calculated. This feedforward compensation reduces the risk of altitude loss due to deformation without altering the attitude command.

[0043] As one embodiment, the application process of the near-wall control method for variable-flying rotorcraft applicable to narrow spaces disclosed herein is as follows: The central body 1 is equipped with two independent deformation modules at the front and rear. Each deformation module includes a set of bidirectional threaded screws 5 driven in the middle, two sliding nuts 6 on the left and right, two parallel guide rails 7, and at least two stages of scissor linkage mechanism 8. When the drive component 4 rotates, the left and right sliding nuts 6 move closer or further apart synchronously under the action of opposite spiral threads, driving the propulsion unit 9 mounting bases at the left and right output ends to retract or expand in pairs.

[0044] When both the front and rear modules are deployed, the aircraft is in a standard deployed configuration. When both the front and rear modules are in a retracted state, the aircraft is in a fully retracted configuration. When the front and rear modules are at different degrees of deformation, the aircraft forms an asymmetric narrow slot configuration; When a narrow slit is detected ahead, the rotor begins to deform at a preset distance and increases the rotor speed in advance according to the shielding thrust correction coefficient to compensate for the decrease in lift. After passing through the slit, it returns to the deployed configuration.

[0045] like Figure 7 The diagram illustrates the complete timeline of an aircraft completing a single slot crossing, including the following key stages: (t0) Cruise Approach Stage: The aircraft flies along a predetermined trajectory in its standard deployed configuration. The onboard sensing components continuously monitor the environment ahead and calculate the size and orientation of the slot in real time; (t1) Trigger Detection Stage: When the width or height of the slot ahead is detected to be less than the current deployed configuration envelope size but greater than the minimum retractable envelope size, the controller determines that the slot is passable and triggers the detection at a preset distance. The deformation process is initiated at point 1; (t2) Deformation and contraction stage: The flight controller calculates the target deformation parameters in real time based on the slit geometry parameters. , The front and rear deformation modules are synchronously or asymmetrically contracted to the adapted configuration. At the same time, the thrust correction coefficient under the current configuration is queried according to the offline calibrated shielding angle-thrust correction curve. The rotor target speed is increased in advance according to formula (11) to compensate for lift attenuation. (t3) Crossing phase: The aircraft maintains the contracted configuration and crosses the slit at the target speed after feedforward compensation. (t4) Recovery and deployment phase: After the aircraft has completely passed through the slit, the controller drives the deformation module to recover to the standard deployment configuration and restores the target speed to the nominal value, and continues to perform subsequent flight missions.

[0046] This disclosure enables the use of two independent deformation modules to control the positions of two pairs of propulsion units, achieving symmetrical and asymmetrical configuration switching with a smaller number of driving components. Each deformation module uses a bidirectional threaded screw to drive the left and right sliding nuts to move symmetrically, reducing the number of driving channels and improving the consistency of left and right movements. The cross nodes of the scissor linkage mechanism cooperate with the guide rail slider to form in-plane deformation, improving the bending and torsional resistance in the unfolded state and suppressing jamming or out-of-plane instability in the contracted state.

[0047] This disclosure addresses the issue of continuously changing dynamic models in deformable bodies by updating the center of gravity, inertia matrix, and control efficiency matrix in real time based on morphological parameters. It separately estimates and fuses the low-frequency bias torque caused by deformation and the high-frequency suction disturbance caused by near-wall effects through dual channels, achieving coordinated suppression of internal and external disturbances. The underlying allocation introduces an effective set method based on WLS, dynamically adjusting the control allocation priority according to the actuator saturation margin, prioritizing overall thrust, roll, and pitch stability.

[0048] Example 2 One embodiment of this disclosure provides a variable-flying rotorcraft, such as... Figure 1 As shown, the system includes a central fuselage 1, a forward deformable module 2, a rear deformable module 3, a drive component 4, a bidirectional threaded screw 5, a sliding nut 6, a guide rail 7, a scissor linkage mechanism 8, four propulsion units 9, a sensing component 10, and a flight controller 11. The forward deformable module 2 is used to adjust the position of the two front propulsion units 9 relative to the central fuselage 1, and the rear deformable module 3 is used to adjust the position of the two rear propulsion units 9 relative to the central fuselage 1. The forward and rear modules can be controlled independently, thereby allowing the aircraft to switch between a standard deployed configuration, a fully retracted configuration, a first asymmetric slit configuration, and a forward unobstructed wall-hugging configuration.

[0049] Furthermore, the central fuselage 1 is used to mount the power battery, flight control motherboard, inertial measurement unit, attitude / position sensor, communication module, and necessary sensing components. The central fuselage 1 has two mounting bases, one at the front and one at the rear, which are connected to the front deformable module 2 and the other at the rear deformable module 3, respectively. The central fuselage 1 can be constructed from a composite material shell, a metal frame, or a combination of both.

[0050] Furthermore, the front deformation module 2 and the rear deformation module 3 are arranged sequentially along the longitudinal direction of the fuselage. Each deformation module includes a drive component 4, a bidirectional threaded screw 5, two sliding nuts 6, at least one pair of guide rails 7, and a guide rail-constrained scissor linkage mechanism 8 connected to the sliding nuts 6. Each deformation module is driven by a drive source to rotate the bidirectional threaded screw 5. The left and right sections of the screw 5 are respectively provided with threads of opposite directions and the same or matched leads, thereby causing the two sliding nuts 6 to synchronously move towards the center or expand to both sides. At any time interval... The displacement of the sliding nut relative to its initial position. It can be calculated using the following formula:

[0051] In the formula, The instantaneous speed of the servo motor driving the device. For the lead of a bidirectional threaded screw, For driving duration.

[0052] Furthermore, each sliding nut 6 is connected to the proximal force-bearing node of the scissor linkage mechanism 8, and at least one cross hinge point of the scissor linkage mechanism 8 engages with the slider on the guide rail 7 to limit the deformation of the linkage mechanism mainly within the plane of the fuselage. The drive servo motor drives the left and right sliding nuts 6 to make linear displacements through the bidirectional threaded screw 5, and amplifies the displacement through the anti-rotation constraint of the scissor linkage mechanism 8 on the guide rail 7, driving the extension and retraction of the propulsion unit mounting base. This structure utilizes the scissor mechanism to amplify the displacement and utilizes the guide rail 7 to share the vertical and lateral loads, improving the bending and torsional resistance in the deployed state and reducing the risk of jamming during high-speed deformation. The screw drive preferably has self-locking or semi-self-locking characteristics, or is equipped with a brake / clutch to suppress external force back drive. Its kinematic geometric mapping relationship can be expressed as:

[0053] in, For the first The lateral deployment coordinates of each propulsion unit For the number of scissor lift unit stages, The length of a single link. For the initial geometric bias, For deformation parameters, This represents the maximum lead screw travel.

[0054] Furthermore, each deformable module has a propulsion unit 9 mounting base at its output end. The propulsion unit 9 includes a motor, an ESC, and a propeller. To prevent rotor interference during retraction, adjacent propulsion units 9 can employ a staggered height, overlapping propeller disks for avoidance, or geometrically staggered blade design. The sensing component 10 preferably includes a camera, a depth sensor, a lidar, or a combination thereof; in a forward-facing unobstructed wall-hugging configuration, the proportion of arm and rotor obstruction within the forward field of view is reduced, thereby improving the effective field of view for wall-hugging detection and near-wall modeling.

[0055] As one embodiment, in the standard deployed configuration, both the front and rear deformable modules are in near-maximum deployed state, resulting in a large rotor spacing and control lever arm; in the fully retracted configuration, both the front and rear deformable modules are in near-minimum deployed state to reduce the lateral envelope width and longitudinal projection size; in the first asymmetric narrow slot configuration, the deformation parameters of the front and rear modules are unequal, causing the two pairs of rotor mounting points to form an asymmetric distribution; in the forward unobstructed wall-hugging configuration, by relatively retracting a group of propulsion units near the nose or tail and changing the arm obstruction relationship, the forward field of view obstruction ratio of the sensing component 10 is reduced. The lateral envelope width of the current configuration... Longitudinal projection length and envelope area All can be represented as , The folding rate, a function of , can be characterized by the following formula:

[0056] in, The envelope area under the standard unfolded configuration. This represents the projected envelope area under the current configuration.

[0057] Example 3 One embodiment of this disclosure provides a near-wall control system for a variable-flying rotorcraft suitable for confined spaces, comprising: The data acquisition module is used to acquire the deformation parameters and flight status data of the aircraft, and reconstructs the deformation parameters based on the principle of superposition of a particle system. The disturbance estimation module is used to estimate the low-frequency bias torque of the internal disturbance rejection channel using a second-order continuous-time extended state observer, and to estimate the high-frequency aerodynamic disturbance of the external disturbance rejection channel based on flight state data. The propulsion allocation module is used to generate a target command vector based on the desired attitude and two disturbance estimates, construct a propulsion control quantity allocation objective function, and use WLS priority control allocation based on the effective set method to obtain the control quantity of each propulsion controller. The flight control module is used to control the aircraft during its deformable flight, to deal with the lift attenuation caused by mutual occlusion of the rotors during the deformable process, to update the independent thrust model based on the occlusion envelope angle calibrated in the offline wind tunnel, and to increase the target rotation speed, so as to achieve adaptive compensation for slit crossing and aerodynamic feedforward, and to restore the aircraft to its deployed configuration after passing through the slit.

[0058] Example 4 One embodiment of this disclosure provides a computer program product, including a computer program that, when executed by a processor, implements the near-wall control method for a variable-fly rotorcraft suitable for confined spaces.

[0059] Example 5 One embodiment of this disclosure provides a non-transitory computer-readable storage medium for storing computer instructions, which, when executed by a processor, implement the near-wall control method for a variable-fly rotorcraft suitable for confined spaces.

[0060] Example 6 One embodiment of this disclosure provides an electronic device, including a processor, a memory, and a computer program; wherein the processor is connected to the memory, the computer program is stored in the memory, and when the electronic device is running, the processor executes the computer program stored in the memory to enable the electronic device to perform the near-wall control method for a variable-fly rotorcraft suitable for narrow spaces.

[0061] This disclosure is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this disclosure. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create a machine for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0062] These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable apparatus for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0063] While the specific embodiments of this disclosure have been described above in conjunction with the accompanying drawings, this is not intended to limit the scope of protection of this disclosure. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art without creative effort based on the technical solutions of this disclosure are still within the scope of protection of this disclosure.

Claims

1. A near-wall control method for variable-flying rotorcraft applicable to confined spaces, characterized in that, include: The deformation parameters and flight status data of the aircraft are obtained, and the deformation parameters are reconstructed based on the principle of superposition of a particle system. The low-frequency bias torque of the internal disturbance rejection channel is estimated using a second-order continuous-time extended state observer, and the high-frequency aerodynamic disturbance of the external disturbance rejection channel is estimated based on flight state data. The target command vector is generated based on the desired attitude and two disturbance estimates. The objective function for propulsion control quantity allocation is constructed, and the control quantity of each propulsion controller is obtained by using WLS priority control allocation based on the effective set method. To address the lift attenuation caused by mutual occlusion of rotors during the deformation flight of the controlled aircraft, the independent thrust model is updated based on the occlusion envelope angle calibrated in the offline wind tunnel, and the target rotation speed is increased to achieve adaptive compensation for slit crossing and aerodynamic feedforward, and the aircraft recovers to the deployed configuration after passing through the slit.

2. The near-wall control method for a variable-flying rotorcraft applicable to confined spaces as described in claim 1, characterized in that, The acquisition of aircraft deformation parameters and flight status data involves reconstructing the deformation parameters based on the principle of superposition of a system of particles, including: The normalized deformation parameters of the front and rear deformation modules are obtained by the position detection component, and the flight attitude quaternion, angular velocity, velocity, position and distance to the wall are obtained by the IMU, visual inertial odometry and radar. Based on the principle of superposition of a system of particles, the position of the center of gravity, the inertia matrix, and the control efficiency matrix corresponding to the current configuration are updated.

3. The near-wall control method for a variable-flying rotorcraft applicable to confined spaces as described in claim 1, characterized in that, The method of estimating the low-frequency bias torque of the internal disturbance rejection channel using a second-order continuous-time extended state observer and estimating the high-frequency aerodynamic disturbance of the external disturbance rejection channel based on flight state data includes: The low-frequency bias torque caused by asymmetric deformation of the airframe, changes in mass distribution, or changes in rotor overlap lift is estimated using a second-order continuous-time extended state observer (ESO). A wall suction model based on a distance attenuation trigger threshold is constructed using angular velocity, thrust residual, and wall distance. A fuzzy sliding mode observer is then used to calculate the high-frequency gust mutation term. The wall suction model based on the distance attenuation trigger threshold is as follows: in, The wall effect trigger threshold distance, This is the suction power proportionality coefficient; For the approximation term of the fuzzy neural network, For angular velocity error, For sliding surface, For robustness gain.

4. The near-wall control method for a variable-flying rotorcraft applicable to confined spaces as described in claim 1, characterized in that, The process involves generating a target command vector based on the desired attitude and two disturbance estimates, constructing a propulsion control quantity allocation objective function, and using WLS priority control allocation based on the effective set method to obtain the control quantities for each propulsion controller, including: The target command vector is generated based on the desired attitude and the disturbance estimate. The underlying incremental control law is expressed as follows: in, , The aerodynamic moment mapping matrix, It is a low-pass filter operator. and This refers to the angular velocity and control increment from the previous sampling period or the reference state. Based on the control effectiveness matrix, the target command is mapped to the control quantity of each propulsion unit. The control allocation objective function is expressed as follows: ,and In the formula, For motor input or input increment, For the expected input, Given the input smoothing weight matrix, This is the task priority weight matrix. This is the priority scaling factor; The effective set algorithm execution process includes: initializing the effective set and feasible solutions; solving for unconstrained control perturbations in the unsaturated motor column vectors; if the motor's physical limits are touched, calculating the interpolation coefficients and adding the motor to the saturated effective set; and when the saturation margin... When approaching 0, adaptively reduce The weighting of the yaw channel is prioritized to ensure total thrust, roll, and pitch channels.

5. A variable-flight rotorcraft, applied to the near-wall control method for a variable-flight rotorcraft suitable for confined spaces as described in any one of claims 1-4, characterized in that, It includes a central fuselage, a forward deformable module, a rear deformable module, four propulsion units, a sensing component, and a flight controller. The forward deformable module adjusts the position of the two front propulsion units relative to the central fuselage, and the rear deformable module adjusts the position of the two rear propulsion units relative to the central fuselage. The forward and rear deformable modules can be controlled independently, thereby enabling the aircraft to switch between a standard deployed configuration, a fully retracted configuration, a first asymmetric slit configuration, and a forward unobstructed wall-hugging configuration.

6. The variable fuselage rotorcraft as described in claim 5, characterized in that, The front and rear deformation modules are arranged longitudinally along the central fuselage. Each deformation module includes a drive unit, a bidirectional threaded screw, two sliding nuts on the left and right, at least one pair of guide rails, and a guide rail-constrained scissor linkage mechanism connected to the sliding nuts. Each deformation module is driven by a drive source to rotate the bidirectional threaded screw. The left and right sections of the bidirectional threaded screw are respectively provided with threads with opposite directions of rotation and the same or matched leads, so that the two sliding nuts on the left and right move towards the center or unfold to the sides synchronously.

7. A near-wall control system for variable-flying rotorcraft suitable for confined spaces, including: The data acquisition module is used to acquire the deformation parameters and flight status data of the aircraft, and reconstructs the deformation parameters based on the principle of superposition of a particle system. The disturbance estimation module is used to estimate the low-frequency bias torque of the internal disturbance rejection channel using a second-order continuous-time extended state observer, and to estimate the high-frequency aerodynamic disturbance of the external disturbance rejection channel based on flight state data. The propulsion allocation module is used to generate a target command vector based on the desired attitude and two disturbance estimates, construct a propulsion control quantity allocation objective function, and use WLS priority control allocation based on the effective set method to obtain the control quantity of each propulsion controller. The flight control module is used to control the aircraft during its deformable flight, to deal with the lift attenuation caused by mutual occlusion of the rotors during the deformable process, to update the independent thrust model based on the occlusion envelope angle calibrated in the offline wind tunnel, and to increase the target rotation speed, so as to achieve adaptive compensation for slit crossing and aerodynamic feedforward, and to restore the aircraft to its deployed configuration after passing through the slit.

8. A computer program product, comprising a computer program, characterized in that, When the computer program is executed by the processor, it implements the near-wall control method for a variable-fly rotorcraft applicable to narrow spaces as described in any one of claims 1-4.

9. A non-transitory computer-readable storage medium, characterized in that, The non-transitory computer-readable storage medium is used to store computer instructions, which, when executed by a processor, implement the near-wall control method for a variable-fly rotorcraft applicable to narrow spaces as described in any one of claims 1-4.

10. An electronic device, characterized in that, include: The device includes a processor, a memory, and a computer program; wherein the processor is connected to the memory, the computer program is stored in the memory, and when the electronic device is running, the processor executes the computer program stored in the memory to cause the electronic device to perform a near-wall control method for a variable-fly rotorcraft applicable to narrow spaces as described in any one of claims 1-4.

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