Air-ground dual-mode full-drive-by-wire carrying system and cooperative control method thereof

Abstract

The invention discloses an air-ground dual-mode full-drive-by-wire carrying system and a cooperative control method thereof. The air-ground dual-mode full-drive-by-wire carrying system comprises an attitude sensor, a height acquisition module, six groups of air-ground dual-mode tilting driving systems, a central controller, a carrying platform and a remote controller, the central controller generates a current control signal according to a roll angle and a pitch angle collected by an attitude sensor, flight height information collected by a height collection module, and a tilt angle and a tilt angle speed of a tilt execution rod collected by a tilt execution rod angle sensor in the air-ground bimodal tilt driving system; and rotor wing tilting motors in the six groups of air-ground dual-mode tilting driving systems are controlled. The invention provides a corresponding cooperative control method aiming at the risks of non-uniform lift force distribution, attitude instability and the like caused by asynchronous rotor tilting angle and tilting angle speed of an existing aircraft, so that continuous, stable and safe control of a system in an air-ground dual-mode conversion process is realized.

Description

Technical Field

[0001] This invention belongs to the field of flying car control technology, specifically relating to an air-ground dual-mode full-linear control vehicle system and its cooperative control method. Background Technology

[0002] Existing aircraft possess strong aerial maneuverability, but their endurance is limited by battery performance and payload, making it difficult to achieve long-duration or long-distance flights. In contrast, ground vehicles have higher endurance and payload capacity, but are limited by terrain, unable to overcome complex obstacles or perform aerial missions. To combine the advantages of both, various air-to-ground dual-mode aircraft have been proposed.

[0003] Dual-mode air-to-ground aircraft can flexibly switch between airborne and ground-based modes, significantly improving transportation efficiency and operational adaptability; however, existing technologies still have the following shortcomings:

[0004] On the one hand, in the process of form conversion of traditional dual-mode aircraft, the control schemes mostly use a single altitude threshold or fixed rate for rotor tilt control, which fails to achieve adaptive adjustment of critical altitude with roll and pitch angles, and does not use roll and pitch angles to constrain rotor tilt angle and tilt angular velocity, resulting in discontinuous attitude changes and obvious transition shocks, making it difficult to adapt to the complex dynamic characteristics in air-to-ground scene switching.

[0005] On the other hand, traditional dual-mode aircraft generally have limited payloads and lack a coordinated control mechanism between rotors, which can easily lead to uneven torque distribution, increased attitude deviations, or even system instability, thereby affecting the operational stability and safety of dual-mode aircraft. Summary of the Invention

[0006] To address the shortcomings of the existing technologies, the present invention aims to provide an air-to-ground dual-modal fully linear control vehicle system and its cooperative control method. This overcomes the problem that existing technologies only consider the influence of altitude on aircraft rotor tilt control, failing to fully account for the coupling effect of dynamic changes in side-pitch and pitch angles on the configuration transition process under heavy loads. The present invention addresses the risks of uneven lift distribution and attitude instability caused by asynchronous rotor tilt angles and tilt angular velocities in existing aircraft by proposing a corresponding cooperative control method, thereby achieving continuous, stable, and safe control of the system during air-to-ground dual-modal transitions.

[0007] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0008] The present invention provides an air-to-ground dual-modal fully linear control vehicle system, comprising: an attitude sensor, a height acquisition module, six sets of air-to-ground dual-modal tilt drive systems, a central controller, a vehicle platform, and a remote controller;

[0009] The attitude sensor is installed inside the carrier platform to collect the tilt and pitch angles of the carrier platform and transmit the data to the central controller.

[0010] The altitude acquisition module is installed inside the carrier platform to collect the flight altitude information of the carrier platform and transmit the data to the central controller;

[0011] The six air-to-ground dual-mode tilt drive systems consist of a first air-to-ground dual-mode tilt drive system, a second air-to-ground dual-mode tilt drive system, a third air-to-ground dual-mode tilt drive system, a fourth air-to-ground dual-mode tilt drive system, a fifth air-to-ground dual-mode tilt drive system, and a sixth air-to-ground dual-mode tilt drive system.

[0012] The first air-to-ground dual-mode tilt drive system, the second air-to-ground dual-mode tilt drive system, the third air-to-ground dual-mode tilt drive system, and the fourth air-to-ground dual-mode tilt drive system are distributed at four diagonal positions on the launch platform to realize lift and attitude control of the launch platform in air mode and drive control in ground mode.

[0013] The fifth air-to-ground dual-mode tilt drive system is located between the first air-to-ground dual-mode tilt drive system and the second air-to-ground dual-mode tilt drive system, and the sixth air-to-ground dual-mode tilt drive system is located between the third air-to-ground dual-mode tilt drive system and the fourth air-to-ground dual-mode tilt drive system. It is used to maintain the attitude stability of the carrier platform during mode transition and to drive control in ground mode.

[0014] The central controller is installed inside the carrier platform. It generates current control signals based on the side tilt and pitch angles collected by the attitude sensors, the flight altitude information collected by the altitude acquisition module, and the tilt angle and tilt angular velocity of the tilt actuators collected by the tilt actuator angle sensors in the air-to-ground dual-mode tilt drive system. It controls the rotor tilt motors in the six sets of air-to-ground dual-mode tilt drive systems.

[0015] The transport platform is used for carrying and transporting goods;

[0016] The remote control is used for information exchange and control between the driver and the central controller.

[0017] Furthermore, each air-to-ground dual-mode tilt drive system consists of a rotor tilt system, a rotor drive system, and a hub drive system;

[0018] The rotor tilting system includes: a rotor tilting motor, a rotor tilting reducer, a tilting actuator, and a tilting actuator angle sensor;

[0019] The rotor tilt motor is connected to the input shaft of the rotor tilt reducer, the output shaft of the rotor tilt reducer is connected to the inner side of the tilt actuator, and the outer side of the tilt actuator is connected to the hub drive motor.

[0020] The tilt actuator angle sensor is installed on the tilt actuator to collect the tilt angle and tilt angular velocity signals of the tilt actuator in real time and transmit them to the central controller;

[0021] The rotor tilt motor operates according to the current control signal output from the central controller. Its output torque is transmitted to the tilt actuator through the rotor tilt reducer to realize the change of the tilt angle and tilt angular velocity of the tilt actuator.

[0022] The rotor drive system includes: a rotor drive motor, a rotor drive reducer, and rotor blades;

[0023] The rotor drive motor is connected to the input shaft of the rotor drive reducer, and the output shaft of the rotor drive reducer is connected to the blades.

[0024] The rotor drive motor operates according to the control signal output by the rotor drive controller of the central controller. Its output torque is transmitted to the blades through the rotor drive reducer, thereby enabling the carrier platform to fly in the air.

[0025] The hub drive system includes: a hub drive motor, a hub drive reducer, and a housing;

[0026] The hub drive motor is connected to the input shaft of the hub drive reducer, and the output shaft of the hub drive reducer is connected to the housing supporting the blades. The outer side of the housing is covered with a layer of highly wear-resistant elastic material.

[0027] The hub drive motor operates according to the control signal output by the hub drive controller of the central controller. Its output torque is transmitted to the housing through the hub drive reducer, thereby driving the housing to rotate and realize the ground travel of the transport platform.

[0028] Furthermore, the central controller includes: a rotor tilt controller, a rotor drive controller, a hub drive controller, and a remote control receiver module;

[0029] The rotor tilt controller includes: a three-coupled dynamic cooperative rotor tilt adjustment controller, a nonlinear exponential state observer, and an air-to-ground dual-mode cooperative controller;

[0030] The three-coupled dynamic cooperative rotor tilt control system calculates the tilt target angles of the first air-to-ground dual-mode tilt drive system, the second air-to-ground dual-mode tilt drive system, the third air-to-ground dual-mode tilt drive system, and the fourth air-to-ground dual-mode tilt drive system based on the roll angle, pitch angle, and flight altitude information of the carrier platform collected by the attitude sensor and altitude acquisition module, and transmits the calculation results to the air-to-ground dual-mode cooperative controller.

[0031] The nonlinear exponential state observer observes the resistance torque on the tilt actuator based on the data collected by the tilt actuator angle sensor and transmits the observation results to the air-ground dual-mode cooperative controller.

[0032] The air-ground dual-mode collaborative controller calculates and outputs current control signals based on the tilt target angle of the tilt actuator, the tilt angle of the tilt actuator, the tilt angular velocity, and the drag torque it experiences, thereby controlling the rotor tilt motor.

[0033] The remote control receiving module is used to receive control signals sent by the remote control and transmit them to the rotor drive controller and the hub drive controller.

[0034] The rotor drive controller controls the rotor drive motor in the rotor drive system according to the control signal received by the remote controller receiving module;

[0035] The hub drive controller controls the hub drive motor in the hub drive system based on the control signal received by the remote controller receiving module.

[0036] Furthermore, the six sets of air-to-ground dual-mode tilt drive systems perform the following steps in different operating modes:

[0037] Flight mode: The six sets of air-to-ground dual-mode tilt drive systems remain horizontal, the tilt actuator angle is 0 degrees, and the rotor drive system generates lift;

[0038] Mode transition mode: When transitioning from flight mode to ground mode, the mode transition mode is performed at a preset altitude. The tilt actuators in the first, second, third, and fourth air-to-ground dual-mode tilt drive systems tilt according to the current control signal output by the air-to-ground dual-mode cooperative controller in the central controller. The tilt actuators in the fifth and sixth air-to-ground dual-mode tilt drive systems maintain a horizontal attitude and continuously provide lift to ensure the attitude stability of the launch platform during the transition process.

[0039] Ground mode: The tilt actuators in the fifth and sixth air-ground dual-mode tilt drive systems tilt to a vertical position; the housings in the six air-ground dual-mode tilt drive systems act as wheels, driven by hub motors to rotate, thereby achieving ground driving.

[0040] The present invention provides a cooperative control method for an air-to-ground dual-mode fully linear motion control vehicle system, based on the aforementioned system, comprising the following steps:

[0041] 1) Based on the collected side tilt and pitch angles of the carrier platform, construct the attitude coupling angle of the carrier platform; based on the attitude coupling angle, design the dynamic upper and lower critical height models of the air-to-ground dual-mode fully linear control carrier system, so as to calculate the tilt target angle of the tilt actuator in the first air-to-ground dual-mode tilt drive system, the second air-to-ground dual-mode tilt drive system, the third air-to-ground dual-mode tilt drive system, and the fourth air-to-ground dual-mode tilt drive system;

[0042] 2) Establish a dynamic model of the rotor tilting system;

[0043] 3) Based on the rotor tilting system dynamic model established in step 2), the tilting angle and tilting angular velocity of the tilting actuator in the air-to-ground dual-mode tilting drive system are collected to observe the drag torque on the rotor tilting mechanism; a multi-parameter collaborative adjustment mechanism is designed to improve the observation accuracy of the nonlinear exponential state observer in the central controller.

[0044] 4) Based on the tilt target angle of the tilt actuator calculated in step 1) and the resistance torque obtained in step 3), design a sliding surface that considers the attitude coupling angle constraint to output current control signal and realize the control of the tilt angle and tilt angular velocity of the rotor tilt mechanism.

[0045] Furthermore, step 1) is specifically as follows:

[0046] 11) Collect the roll and pitch angles of the launch platform, and construct the attitude coupling angle of the launch platform, expressed as follows:

[0047] ;

[0048] in, The attitude coupling angle of the launch platform; The tilt angle of the transport platform; The pitch angle of the transport platform; The roll angle coupling weight; For pitch angle coupling weights;

[0049] 12) Based on the attitude coupling angle of the launch platform in step 11), design the dynamic upper and lower critical height models of the air-to-ground dual-mode fully linear control launch system, as follows:

[0050] ;

[0051] ;

[0052] in, This is the dynamic upper critical height; for The minimum value; for The maximum value; This is the rate coefficient for adjusting the low attitude coupling angle; The attitude coupling angle adjustment rate coefficient; The threshold for low-to-medium attitude coupling angle segmentation; The threshold for segmentation of the mid-to-high attitude coupling angle; It is the saturation smoothing coefficient; This represents the dynamic upper critical height transition threshold within the low-to-medium attitude coupling angle range. ; This is the safety threshold for the attitude coupling angle; The dynamic upper critical height adaptation threshold before saturation in the medium-to-high attitude coupling angle range; ; This refers to the dynamic critical height. The critical height transition threshold under dynamic conditions in the low-to-medium attitude coupling angle range; ; This is the adaptation threshold before critical height saturation under dynamic conditions in the medium-to-high attitude coupling angle range. ; for The minimum value; for The minimum value;

[0053] 13) Based on the dynamic upper and lower critical heights output by the dynamic upper and lower critical height model of the air-to-ground dual-mode fully linear control vehicle system in step 12), the tilt target angles of the tilt actuators in the first, second, third, and fourth air-to-ground dual-mode tilt drive systems are calculated as follows:

[0054] ;

[0055] in, This refers to the current altitude of the transport platform; The target tilt angle for the tilt actuator; This is the attitude coupling angle attenuation factor. , is a constant, and k is the attenuation coefficient of the attitude coupling angle attenuation factor; To truncate the Sigmoid function, the expression is as follows:

[0056] ;

[0057] Where x is the input variable for truncating the Sigmoid function.

[0058] Furthermore, the specific steps for establishing the dynamic model of the rotor tilting system in step 2) are as follows:

[0059] 21) Establish the dynamic model of the rotor tilting motor as follows:

[0060] (1);

[0061] in, , These are the moment of inertia and damping coefficient of the rotor tilt motor, respectively. The angle of the rotor tilt motor; This refers to the output torque of the tilt rotor motor; The electromagnetic torque of the tilt rotor motor; This is the input current for the rotor tilt motor; The electromagnetic torque coefficient of the rotor tilt motor; the subscripts i=1, 2, 3, 4 represent the first air-to-ground dual-mode tilt drive system, the second air-to-ground dual-mode tilt drive system, the third air-to-ground dual-mode tilt drive system, and the fourth air-to-ground dual-mode tilt drive system, respectively.

[0062] 22) Establish the dynamic model of the rotor tilt reducer and tilt actuator as follows:

[0063] (2);

[0064] in, , These are the moment of inertia and damping coefficient of the rotor tilt reducer and tilt actuator assembly, respectively. The tilt angle of the tilt actuator; The torque that the rotor tilt motor exerts on the tilt actuator through the rotor tilt reducer; The drag torque is caused by friction and gravity.

[0065] The angle of the rotor tilt motor Tilting angle with tilt actuator The following relationship exists:

[0066] (3);

[0067] in, The reduction ratio of the rotor tilt reducer;

[0068] 23) The dynamic model of the rotor tilting system can be obtained from equations (1), (2), and (3) as follows:

[0069] ;

[0070] in, and These are the equivalent moment of inertia and equivalent damping coefficient of the rotor tilting system, respectively. , ;

[0071] make , The state-space equations of the rotor tilting system can be obtained as follows:

[0072] ;

[0073] in, Let be the first state variable of the i-th rotor tilting system; Let be the second state variable of the i-th rotor tilting system.

[0074] Furthermore, step 3) is specifically as follows:

[0075] 31) Using the collected tilt angle and tilt angular velocity of the tilt actuator, the drag torque on the rotor tilt mechanism is observed. ,as follows:

[0076] (4);

[0077] in, , They are respectively , Observed values; for Observed values; The base gain for tilt angle observation; For tilt angle observation error feedback gain; The base gain for tilt angular velocity observation; This is the gain for tilt angular velocity error feedback;

[0078] 32) Design a multi-parameter coordinated adjustment mechanism to improve the observation accuracy of the nonlinear exponential state observer, as follows:

[0079] ;

[0080] in, ; ; Let be the observed error of the tilt angle of the tilt actuator in the i-th air-ground dual-mode tilt drive system. The tilt angular velocity observation error of the tilt actuator in the i-th air-ground dual-mode tilt drive system; for Maximum allowed value; for Dynamically adjustable gain; for The rate of change of gain is adjusted; for The rate of change of gain is adjusted; for Dynamically adjustable gain; for Auxiliary adjustment gain; for The coupling adjustment gain; for The rate of change adjusts the gain.

[0081] Furthermore, step 4) is specifically as follows:

[0082] 41) Based on the tilt target angle of the tilt actuator output in step 1), calculate the tilt angle coordination error of the tilt actuator in the i-th air-ground dual-mode tilt drive system. Co-operational error with tilt angular velocity for:

[0083] ;

[0084] in, ; ; Let be the first state variable of the j-th rotor tilting system; Let j be the second state variable of the j-th rotor tilting system; the subscripts j=1, 2, 3, 4 represent the first air-to-ground dual-mode tilting drive system, the second air-to-ground dual-mode tilting drive system, the third air-to-ground dual-mode tilting drive system, and the fourth air-to-ground dual-mode tilting drive system, respectively.

[0085] 42) The tilt angle coordination error of the tilt actuator in the i-th air-ground dual-mode tilt drive system. Differentiating with respect to time t yields the dynamic equation for the tilt angle cooperative error:

[0086] (5);

[0087] 43) Differentiating equation (5) with respect to time t, we can obtain the following dynamic equation for the coordinated error of the tilt angular velocity of the tilt actuator in the i-th air-ground dual-mode tilt drive system:

[0088] ;

[0089] 44) Design a sliding surface that considers attitude coupling angle constraints, as follows:

[0090] (6);

[0091] in, It is a sliding surface; For the integral term gain; This is the parameter of the first tilt angle error power; This is the second tilt angle error power parameter; The parameter is the power of the first attitude coupling angle error. The second attitude coupling angle error is a power parameter; t is the upper limit of integration. For integration variables; For attitude coupling angle error, ; Adjust the gain to account for attitude coupling angle error; The tilt angle coordination error of the tilt actuator in the j-th air-ground dual-mode tilt drive system;

[0092] 45) Differentiating equation (6) with respect to time t yields:

[0093] ;

[0094] 46) Order , The equivalent control law of the i-th air-ground dual-mode tilt drive system is calculated. The expression is as follows:

[0095] ;

[0096] 47) Calculate the sliding mode control rate The expression is as follows:

[0097] ;

[0098] in, This is the gain coefficient; The parameter is adjusted by power. For attenuation adjustment parameters;

[0099] 48) Using the observed drag torque and equivalent control law of the rotor tilting mechanism in the i-th air-to-ground dual-mode tilting drive system Sliding mode control rate The current control signal is calculated. ,as follows:

[0100] ;

[0101] 49) Based on the current control signal The rotor tilt motor drives the tilting actuator to control the tilting angle and tilting angular velocity.

[0102] The beneficial effects of this invention are:

[0103] 1. Based on fully considering the influence of the tilt and pitch coupling of the carrier platform, this invention can achieve adaptive adjustment of the tilt target angle of the tilt actuator during the air-to-ground dual-mode transition, thereby maintaining the continuity, stability and safety of dynamic characteristics under different attitude conditions, and ensuring a smooth transition of the carrier platform in complex air-to-ground scene switching.

[0104] 2. This invention constructs a sliding surface that considers the constraints of roll and pitch angles, solves for the equivalent control law and sliding control law, and combines external disturbance factors to achieve high-precision coordinated control of the rotor tilting system. This invention can force the roll and pitch angles of the launch platform to converge to near the origin, and at the same time make the coordinated error of tilt angle and tilt angular velocity between multiple rotor tilting systems converge to zero. This effectively avoids problems such as center of gravity shift, attitude oscillation and sudden change of support force caused by excessive roll and pitch angles under heavy load conditions, and ensures that the launch platform maintains a horizontally stable attitude during ground travel, air flight and air-to-ground mode switching. Attached Figure Description

[0105] Figure 1 This is a schematic diagram of the air-to-ground dual-mode fully linear control vehicle system of the present invention;

[0106] Figure 2 This is a schematic diagram of the rotor tilting system in this invention;

[0107] Figure 3 This is a schematic diagram of the rotor drive system in this invention;

[0108] Figure 4 This is a schematic diagram of the hub drive system in this invention;

[0109] Figure 5 This is a schematic diagram of the central controller in this invention;

[0110] Figure 6 This is a schematic diagram of the air-ground dual-mode fully linear control vehicle system of the present invention as a function of altitude. Detailed Implementation

[0111] To facilitate understanding by those skilled in the art, the present invention will be further described below with reference to embodiments and accompanying drawings. The content mentioned in the embodiments is not intended to limit the present invention.

[0112] Reference Figures 1 to 5As shown, the present invention provides an air-to-ground dual-modal fully linear control vehicle system, comprising: an attitude sensor 1, a height acquisition module 2, six sets of air-to-ground dual-modal tilt drive systems, a central controller 3, a vehicle platform 4, and a remote controller;

[0113] The attitude sensor 1 is installed inside the carrier platform 4 to collect the tilt angle and pitch angle of the carrier platform 4 and transmit the data to the central controller 3;

[0114] The altitude acquisition module 2 is installed inside the carrier platform 4 and is used to collect the flight altitude information of the carrier platform 4 and transmit the data to the central controller 3;

[0115] The six air-to-ground dual-mode tilt drive systems consist of a first air-to-ground dual-mode tilt drive system, a second air-to-ground dual-mode tilt drive system, a third air-to-ground dual-mode tilt drive system, a fourth air-to-ground dual-mode tilt drive system, a fifth air-to-ground dual-mode tilt drive system, and a sixth air-to-ground dual-mode tilt drive system.

[0116] The first air-to-ground dual-mode tilt drive system, the second air-to-ground dual-mode tilt drive system, the third air-to-ground dual-mode tilt drive system and the fourth air-to-ground dual-mode tilt drive system are distributed at the four diagonal positions of the carrier platform 4, and are used to realize the lift and attitude control of the carrier platform in the air mode, and the drive control in the ground mode.

[0117] The fifth air-to-ground dual-mode tilt drive system is located between the first air-to-ground dual-mode tilt drive system and the second air-to-ground dual-mode tilt drive system, and the sixth air-to-ground dual-mode tilt drive system is located between the third air-to-ground dual-mode tilt drive system and the fourth air-to-ground dual-mode tilt drive system. It is used to maintain the attitude stability of the carrier platform 4 during mode transition and to drive control in ground mode.

[0118] The central controller 3 is installed inside the carrier platform 4. Based on the side tilt angle and pitch angle collected by the attitude sensor 1, the flight altitude information collected by the altitude acquisition module 2, and the tilt angle and tilt angular velocity of the tilt actuator collected by the tilt actuator angle sensor in the air-to-ground dual-mode tilt drive system, it generates a current control signal to control the rotor tilt motors of the six sets of air-to-ground dual-mode tilt drive systems.

[0119] The transport platform 4 is used for carrying and transporting goods;

[0120] The remote control is used for information exchange and operation control between the driver and the central controller 3.

[0121] Each air-to-ground dual-mode tilt drive system consists of a rotor tilt system, a rotor drive system, and a hub drive system.

[0122] The rotor tilting system includes: a rotor tilting motor 5, a rotor tilting reducer 6, a tilting actuator 7, and a tilting actuator angle sensor 8;

[0123] The rotor tilt motor 5 is connected to the input shaft of the rotor tilt reducer 6, the output shaft of the rotor tilt reducer 6 is connected to the inner side of the tilt actuator 7, and the outer side of the tilt actuator 7 is connected to the hub drive motor 12.

[0124] The tilt actuator angle sensor 8 is installed on the tilt actuator 7 to collect the tilt angle and tilt angular velocity signals of the tilt actuator in real time and transmit them to the central controller 3;

[0125] The rotor tilt motor 5 operates according to the current control signal output from the central controller 3. Its output torque is transmitted to the tilt actuator 7 through the rotor tilt reducer 6 to realize the change of tilt angle and tilt angular velocity of the tilt actuator.

[0126] The rotor drive system includes: a rotor drive motor 9, a rotor drive reducer 10, and blades 11;

[0127] The rotor drive motor 9 is connected to the input shaft of the rotor drive reducer 10, and the output shaft of the rotor drive reducer 10 is connected to the blade 11.

[0128] The rotor drive motor 9 operates according to the control signal output by the rotor drive controller 16 of the central controller 3. Its output torque is transmitted to the blade 11 through the rotor drive reducer 10, thereby realizing the aerial flight of the carrier platform.

[0129] The hub drive system includes: a hub drive motor 12, a hub drive reducer 13, and a housing 14;

[0130] The hub drive motor 12 is connected to the input shaft of the hub drive reducer 13, and the output shaft of the hub drive reducer 13 is connected to the housing 14 that supports the blades. The outer side of the housing 14 is covered with a layer of highly wear-resistant elastic material.

[0131] The hub drive motor 12 operates according to the control signal output by the hub drive controller 17 of the central controller 3. Its output torque is transmitted to the housing 14 through the hub drive reducer 13, thereby driving the housing 14 to rotate, so as to realize the ground travel of the transport platform 4.

[0132] Specifically, the central controller 3 includes: a rotor tilt controller 15, a rotor drive controller 16, a hub drive controller 17, and a remote control receiver module 18;

[0133] The rotor tilt controller 15 includes: a three-coupled dynamic cooperative rotor tilt adjustment controller 19, a nonlinear exponential state observer 20, and an air-to-ground dual-mode cooperative controller 21;

[0134] The three-coupled dynamic cooperative rotor tilt control controller 19 calculates the tilt target angles of the first air-to-ground dual-mode tilt drive system, the second air-to-ground dual-mode tilt drive system, the third air-to-ground dual-mode tilt drive system, and the fourth air-to-ground dual-mode tilt drive system based on the side tilt angle, pitch angle, and flight altitude information of the carrier platform collected by the attitude sensor 1 and the altitude acquisition module 2, and transmits the calculation results to the air-to-ground dual-mode cooperative controller 21.

[0135] The nonlinear exponential state observer 20 observes the resistance torque on the tilt actuator based on the data collected by the tilt actuator angle sensor 8, and transmits the observation results to the air-ground dual-mode cooperative controller 21;

[0136] The air-ground dual-mode collaborative controller 21 calculates and outputs a current control signal based on the tilt target angle of the tilt actuator, the tilt angle of the tilt actuator, the tilt angular velocity, and the resistance torque it experiences, thereby controlling the rotor tilt motor 5.

[0137] The remote control receiving module 18 is used to receive control signals sent by the remote control and transmit them to the rotor drive controller 16 and the hub drive controller 17.

[0138] The rotor drive controller 16 controls the rotor drive motor 9 in the rotor drive system according to the control signal received by the remote controller receiving module.

[0139] The hub drive controller 17 controls the hub drive motor 12 in the hub drive system according to the control signal received by the remote controller receiving module.

[0140] Reference Figure 6 As shown, the six sets of air-to-ground dual-mode tilt drive systems perform the following steps in different operating modes:

[0141] Flight mode: The six sets of air-to-ground dual-mode tilt drive systems remain horizontal, the tilt actuator angle is 0 degrees, and the rotor drive system generates lift;

[0142] Mode transition mode: When transitioning from flight mode to ground mode, the mode transition mode is performed at a preset altitude. The tilt actuators in the first, second, third, and fourth air-to-ground dual-mode tilt drive systems tilt according to the current control signal output by the air-to-ground dual-mode cooperative controller in the central controller. The tilt actuators in the fifth and sixth air-to-ground dual-mode tilt drive systems maintain a horizontal attitude and continuously provide lift to ensure the attitude stability of the launch platform during the transition process.

[0143] Ground mode: The tilt actuators in the fifth and sixth air-ground dual-mode tilt drive systems tilt to a vertical position; the housings in the six air-ground dual-mode tilt drive systems act as wheels, driven by hub motors to rotate, thereby achieving ground driving.

[0144] The present invention provides a cooperative control method for an air-to-ground dual-mode fully linear motion control vehicle system, based on the aforementioned system, comprising the following steps:

[0145] 1) Based on the collected roll and pitch angles of the launch platform, construct the attitude coupling angle of the launch platform; based on the attitude coupling angle, design dynamic upper and lower critical height models of the air-to-ground dual-mode fully linear control launch system to calculate the tilt target angles of the tilt actuators in the first, second, third, and fourth air-to-ground dual-mode tilt drive systems; specifically as follows:

[0146] 11) Collect the roll and pitch angles of the launch platform, and construct the attitude coupling angle of the launch platform, expressed as follows:

[0147] ;

[0148] in, The attitude coupling angle of the launch platform; The tilt angle of the transport platform; The pitch angle of the transport platform; The roll angle coupling weight; For pitch angle coupling weights;

[0149] 12) Based on the attitude coupling angle of the launch platform in step 11), design the dynamic upper and lower critical height models of the air-to-ground dual-mode fully linear control launch system, as follows:

[0150] ;

[0151] ;

[0152] in, This is the dynamic upper critical height; for The minimum value; for The maximum value; This is the rate coefficient for adjusting the low attitude coupling angle; The attitude coupling angle adjustment rate coefficient; The threshold for low-to-medium attitude coupling angle segmentation; The threshold for segmentation of the mid-to-high attitude coupling angle; It is the saturation smoothing coefficient; This represents the dynamic upper critical height transition threshold within the low-to-medium attitude coupling angle range. ; This is the safety threshold for the attitude coupling angle; The dynamic upper critical height adaptation threshold before saturation in the medium-to-high attitude coupling angle range; ; This refers to the dynamic critical height. The critical height transition threshold under dynamic conditions in the low-to-medium attitude coupling angle range; ; This is the adaptation threshold before critical height saturation under dynamic conditions in the medium-to-high attitude coupling angle range. ; for The minimum value; for The minimum value;

[0153] 13) Based on the dynamic upper and lower critical heights output by the dynamic upper and lower critical height model of the air-to-ground dual-mode fully linear control vehicle system in step 12), the tilt target angles of the tilt actuators in the first, second, third, and fourth air-to-ground dual-mode tilt drive systems are calculated as follows:

[0154] ;

[0155] in, This refers to the current altitude of the transport platform; The target tilt angle for the tilt actuator; This is the attitude coupling angle attenuation factor. , is a constant, and k is the attenuation coefficient of the attitude coupling angle attenuation factor; To truncate the Sigmoid function, the expression is as follows:

[0156] ;

[0157] Where x is the input variable for truncating the Sigmoid function.

[0158] 2) Establish a dynamic model of the rotor tilting system; details are as follows:

[0159] 21) Establish the dynamic model of the rotor tilting motor as follows:

[0160] (1);

[0161] in, , These are the moment of inertia and damping coefficient of the rotor tilt motor, respectively. The angle of the rotor tilt motor; This refers to the output torque of the tilt rotor motor; The electromagnetic torque of the tilt rotor motor; This is the input current for the rotor tilt motor; The electromagnetic torque coefficient of the rotor tilt motor; the subscripts i=1, 2, 3, 4 represent the first air-to-ground dual-mode tilt drive system, the second air-to-ground dual-mode tilt drive system, the third air-to-ground dual-mode tilt drive system, and the fourth air-to-ground dual-mode tilt drive system, respectively.

[0162] 22) Establish the dynamic model of the rotor tilt reducer and tilt actuator as follows:

[0163] (2);

[0164] in, , These are the moment of inertia and damping coefficient of the rotor tilt reducer and tilt actuator assembly, respectively. The tilt angle of the tilt actuator; The torque that the rotor tilt motor exerts on the tilt actuator through the rotor tilt reducer; The drag torque is caused by friction and gravity.

[0165] The angle of the rotor tilt motor Tilting angle with tilt actuator The following relationship exists:

[0166] (3);

[0167] in, The reduction ratio of the rotor tilt reducer;

[0168] 23) The dynamic model of the rotor tilting system can be obtained from equations (1), (2), and (3) as follows:

[0169] ;

[0170] in, and These are the equivalent moment of inertia and equivalent damping coefficient of the rotor tilting system, respectively. , ;

[0171] make , The state-space equations of the rotor tilting system can be obtained as follows:

[0172] ;

[0173] in, Let be the first state variable of the i-th rotor tilting system; Let be the second state variable of the i-th rotor tilting system.

[0174] 3) Based on the rotor tilting system dynamic model established in step 2), the tilting angle and tilting angular velocity of the tilting actuator in the air-to-ground dual-mode tilting drive system are collected to observe the drag torque on the rotor tilting mechanism; a multi-parameter collaborative adjustment mechanism is designed to improve the observation accuracy of the nonlinear exponential state observer in the central controller; the details are as follows:

[0175] 31) Using the collected tilt angle and tilt angular velocity of the tilt actuator, the drag torque on the rotor tilt mechanism is observed. ,as follows:

[0176] (4);

[0177] in, , They are respectively , Observed values; for Observed values; The base gain for tilt angle observation; For tilt angle observation error feedback gain; The base gain for tilt angular velocity observation; This is the gain for tilt angular velocity error feedback;

[0178] 32) Design a multi-parameter coordinated adjustment mechanism to improve the observation accuracy of the nonlinear exponential state observer, as follows:

[0179] ;

[0180] in, ; ; Let be the observed error of the tilt angle of the tilt actuator in the i-th air-ground dual-mode tilt drive system. The tilt angular velocity observation error of the tilt actuator in the i-th air-ground dual-mode tilt drive system; for Maximum allowed value; for Dynamically adjustable gain; for The rate of change of gain is adjusted; for The rate of change of gain is adjusted; for Dynamically adjustable gain; for Auxiliary adjustment gain; for The coupling adjustment gain; for The rate of change adjusts the gain.

[0181] 4) Based on the target tilt angle of the tilt actuator calculated in step 1) and the resistance torque obtained in step 3), design a sliding surface that considers attitude coupling angle constraints to output a current control signal, thereby controlling the tilt angle and tilt angular velocity of the rotor tilt mechanism; specifically as follows:

[0182] 41) Based on the tilt target angle of the tilt actuator output in step 1), calculate the tilt angle coordination error of the tilt actuator in the i-th air-ground dual-mode tilt drive system. Co-operational error with tilt angular velocity for:

[0183] ;

[0184] in, ; ; Let be the first state variable of the j-th rotor tilting system; Let j be the second state variable of the j-th rotor tilting system; the subscripts j=1, 2, 3, 4 represent the first air-to-ground dual-mode tilting drive system, the second air-to-ground dual-mode tilting drive system, the third air-to-ground dual-mode tilting drive system, and the fourth air-to-ground dual-mode tilting drive system, respectively.

[0185] 42) The tilt angle coordination error of the tilt actuator in the i-th air-ground dual-mode tilt drive system. Differentiating with respect to time t yields the dynamic equation for the tilt angle cooperative error:

[0186] (5);

[0187] 43) Differentiating equation (5) with respect to time t, we can obtain the following dynamic equation for the coordinated error of the tilt angular velocity of the tilt actuator in the i-th air-ground dual-mode tilt drive system:

[0188] ;

[0189] 44) Design a sliding surface that considers attitude coupling angle constraints, as follows:

[0190] (6);

[0191] in, It is a sliding surface; For the integral term gain; This is the parameter of the first tilt angle error power; This is the second tilt angle error power parameter; The parameter is the power of the first attitude coupling angle error. The second attitude coupling angle error is a power parameter; t is the upper limit of integration. For integration variables; For attitude coupling angle error, ; Adjust the gain to account for attitude coupling angle error; The tilt angle coordination error of the tilt actuator in the j-th air-ground dual-mode tilt drive system;

[0192] 45) Differentiating equation (6) with respect to time t yields:

[0193] ;

[0194] 46) Order , The equivalent control law of the i-th air-ground dual-mode tilt drive system is calculated. The expression is as follows:

[0195] ;

[0196] 47) Calculate the sliding mode control rate The expression is as follows:

[0197] ;

[0198] in, This is the gain coefficient; The parameter is adjusted by power. For attenuation adjustment parameters;

[0199] 48) Using the observed drag torque and equivalent control law of the rotor tilting mechanism in the i-th air-to-ground dual-mode tilting drive system Sliding mode control rate The current control signal is calculated. ,as follows:

[0200] ;

[0201] 49) Based on the current control signal The rotor tilt motor drives the tilting actuator to control the tilting angle and tilting angular velocity.

[0202] This invention has many specific applications. The above description is only a preferred embodiment of this invention. It should be noted that for those skilled in the art, several improvements can be made without departing from the principle of this invention, and these improvements should also be considered within the scope of protection of this invention.

Claims

1. A dual-mode air-to-ground fully linear control vehicle system, characterized in that, Includes: attitude sensor, altitude acquisition module, six sets of air-to-ground dual-mode tilt drive system, central controller, transport platform and remote controller; The attitude sensor is installed inside the carrier platform to collect the tilt and pitch angles of the carrier platform and transmit the data to the central controller. The altitude acquisition module is installed inside the carrier platform to collect the flight altitude information of the carrier platform and transmit the data to the central controller; The six air-to-ground dual-mode tilt drive systems consist of a first air-to-ground dual-mode tilt drive system, a second air-to-ground dual-mode tilt drive system, a third air-to-ground dual-mode tilt drive system, a fourth air-to-ground dual-mode tilt drive system, a fifth air-to-ground dual-mode tilt drive system, and a sixth air-to-ground dual-mode tilt drive system. The first air-to-ground dual-mode tilt drive system, the second air-to-ground dual-mode tilt drive system, the third air-to-ground dual-mode tilt drive system, and the fourth air-to-ground dual-mode tilt drive system are distributed at the four diagonal positions of the launch platform to realize the lift and attitude control of the launch platform in the air mode, as well as the drive control in the ground mode. The fifth air-to-ground dual-mode tilt drive system is located between the first air-to-ground dual-mode tilt drive system and the second air-to-ground dual-mode tilt drive system. The sixth air-to-ground dual-mode tilt drive system is located between the third air-to-ground dual-mode tilt drive system and the fourth air-to-ground dual-mode tilt drive system. It is used to maintain the attitude stability of the transport platform during mode transition and to drive control in ground mode. The central controller is installed inside the carrier platform. It generates current control signals based on the side tilt and pitch angles collected by the attitude sensors, the flight altitude information collected by the altitude acquisition module, and the tilt angle and tilt angular velocity of the tilt actuators collected by the tilt actuator angle sensors in the air-to-ground dual-mode tilt drive system. It controls the rotor tilt motors in the six sets of air-to-ground dual-mode tilt drive systems. The transport platform is used for carrying and transporting goods; The remote control is used for information exchange and control between the driver and the central controller.

2. The air-to-ground dual-mode fully linear control vehicle system according to claim 1, characterized in that, Each air-ground dual-mode tilt drive system consists of a rotor tilt system, a rotor drive system, and a hub drive system. The rotor tilting system includes: a rotor tilting motor, a rotor tilting reducer, a tilting actuator, and a tilting actuator angle sensor; The rotor tilt motor is connected to the input shaft of the rotor tilt reducer, the output shaft of the rotor tilt reducer is connected to the inner side of the tilt actuator, and the outer side of the tilt actuator is connected to the hub drive motor. The tilt actuator angle sensor is installed on the tilt actuator to collect the tilt angle and tilt angular velocity signals of the tilt actuator in real time and transmit them to the central controller; The rotor tilt motor operates according to the current control signal output from the central controller. Its output torque is transmitted to the tilt actuator through the rotor tilt reducer to realize the change of the tilt angle and tilt angular velocity of the tilt actuator. The rotor drive system includes: a rotor drive motor, a rotor drive reducer, and rotor blades; The rotor drive motor is connected to the input shaft of the rotor drive reducer, and the output shaft of the rotor drive reducer is connected to the blades. The rotor drive motor operates according to the control signal output by the rotor drive controller of the central controller. Its output torque is transmitted to the blades through the rotor drive reducer, thereby enabling the carrier platform to fly in the air. The hub drive system includes: a hub drive motor, a hub drive reducer, and a housing; The hub drive motor is connected to the input shaft of the hub drive reducer, and the output shaft of the hub drive reducer is connected to the housing supporting the blades. The outer side of the housing is covered with a layer of highly wear-resistant elastic material. The hub drive motor operates according to the control signal output by the hub drive controller of the central controller. Its output torque is transmitted to the housing through the hub drive reducer, thereby driving the housing to rotate and realize the ground travel of the transport platform.

3. The air-to-ground dual-mode fully linear control vehicle system according to claim 2, characterized in that, The central controller includes: a rotor tilt controller, a rotor drive controller, a hub drive controller, and a remote control receiver module; The rotor tilt controller includes: a three-coupled dynamic cooperative rotor tilt adjustment controller, a nonlinear exponential state observer, and an air-to-ground dual-mode cooperative controller; The three-coupled dynamic cooperative rotor tilt control system calculates the tilt target angles of the first air-to-ground dual-mode tilt drive system, the second air-to-ground dual-mode tilt drive system, the third air-to-ground dual-mode tilt drive system, and the fourth air-to-ground dual-mode tilt drive system based on the roll angle, pitch angle, and flight altitude information of the carrier platform collected by the attitude sensor and altitude acquisition module, and transmits the calculation results to the air-to-ground dual-mode cooperative controller. The nonlinear exponential state observer observes the resistance torque on the tilt actuator based on the data collected by the tilt actuator angle sensor and transmits the observation results to the air-ground dual-mode cooperative controller. The air-ground dual-mode collaborative controller calculates and outputs current control signals based on the target tilt angle of the tilt actuator, the tilt angle of the tilt actuator, the tilt angular velocity, and the drag torque it experiences, thereby controlling the rotor tilt motor. The remote control receiving module is used to receive control signals sent by the remote control and transmit them to the rotor drive controller and the hub drive controller. The rotor drive controller controls the rotor drive motor in the rotor drive system according to the control signal received by the remote controller receiving module; The hub drive controller controls the hub drive motor in the hub drive system based on the control signal received by the remote controller receiving module.

4. The air-to-ground dual-mode fully linear control vehicle system according to claim 3, characterized in that, The six sets of air-to-ground dual-mode tilt drive systems perform the following steps in different operating modes: Flight mode: The six sets of air-to-ground dual-mode tilt drive systems remain horizontal, the tilt actuator angle is 0 degrees, and the rotor drive system generates lift; Mode transition mode: When transitioning from flight mode to ground mode, the mode transition mode is performed at a preset altitude. The tilt actuators in the first, second, third, and fourth air-to-ground dual-mode tilt drive systems tilt according to the current control signal output by the air-to-ground dual-mode cooperative controller in the central controller. The tilt actuators in the fifth and sixth air-to-ground dual-mode tilt drive systems maintain a horizontal attitude and continuously provide lift to ensure the attitude stability of the launch platform during the transition process. Ground mode: The tilt actuators in the fifth and sixth air-ground dual-mode tilt drive systems tilt to a vertical position; the housings in the six air-ground dual-mode tilt drive systems act as wheels, driven by hub motors to rotate, thereby achieving ground driving.

5. A cooperative control method for an air-to-ground dual-modal full-track control vehicle system, based on the system described in any one of claims 1-4, characterized in that, The method includes the following steps: 1) Based on the collected side tilt and pitch angles of the carrier platform, construct the attitude coupling angle of the carrier platform; based on the attitude coupling angle, design the dynamic upper and lower critical height models of the air-to-ground dual-mode fully linear control carrier system, so as to calculate the tilt target angle of the tilt actuator in the first air-to-ground dual-mode tilt drive system, the second air-to-ground dual-mode tilt drive system, the third air-to-ground dual-mode tilt drive system, and the fourth air-to-ground dual-mode tilt drive system; 2) Establish a dynamic model of the rotor tilting system; 3) Based on the rotor tilting system dynamic model established in step 2), the tilting angle and tilting angular velocity of the tilting actuator in the air-to-ground dual-mode tilting drive system are collected to observe the drag torque on the rotor tilting mechanism; a multi-parameter collaborative adjustment mechanism is designed to improve the observation accuracy of the nonlinear exponential state observer in the central controller. 4) Based on the tilt target angle of the tilt actuator calculated in step 1) and the resistance torque obtained in step 3), design a sliding surface that considers attitude coupling angle constraints to output current control signals and realize the control of the tilt angle and tilt angular velocity of the rotor tilt mechanism.

6. The collaborative control method for the air-to-ground dual-mode fully linear motion control vehicle system according to claim 5, characterized in that, Step 1) is as follows: 11) Collect the roll and pitch angles of the launch platform, and construct the attitude coupling angle of the launch platform, expressed as follows: ； in, The attitude coupling angle of the launch platform; The tilt angle of the transport platform; The pitch angle of the transport platform; The roll angle coupling weight; For pitch angle coupling weights; 12) Based on the attitude coupling angle of the launch platform in step 11), design the dynamic upper and lower critical height models of the air-to-ground dual-mode fully linear control launch system, as follows: ； ； in, This is the dynamic upper critical height; for The minimum value; for The maximum value; This is the rate coefficient for adjusting the low attitude coupling angle; The attitude coupling angle adjustment rate coefficient; The threshold for low-to-medium attitude coupling angle segmentation; The threshold for segmentation of the mid-to-high attitude coupling angle; It is the saturation smoothing coefficient; This represents the dynamic upper critical height transition threshold within the low-to-medium attitude coupling angle range. ; This is the safety threshold for the attitude coupling angle; The dynamic upper critical height adaptation threshold before saturation in the medium-to-high attitude coupling angle range; ; This refers to the dynamic critical height. The critical height transition threshold under dynamic conditions in the low-to-medium attitude coupling angle range; ; This is the adaptation threshold before critical height saturation under dynamic conditions in the medium-to-high attitude coupling angle range. ; for The minimum value; for The minimum value; 13) Based on the dynamic upper and lower critical heights output by the dynamic upper and lower critical height model of the air-to-ground dual-mode fully linear control vehicle system in step 12), the tilt target angles of the tilt actuators in the first, second, third, and fourth air-to-ground dual-mode tilt drive systems are calculated as follows: ； in, This refers to the current altitude of the transport platform; The target tilt angle for the tilt actuator; This is the attitude coupling angle attenuation factor. , is a constant, and k is the attenuation coefficient of the attitude coupling angle attenuation factor; To truncate the Sigmoid function, the expression is as follows: ； Where x is the input variable for truncating the Sigmoid function.

7. The cooperative control method for the air-to-ground dual-mode full-line control vehicle system according to claim 6, characterized in that, The specific steps for establishing the dynamic model of the rotor tilting system in step 2) are as follows: 21) Establish the dynamic model of the rotor tilting motor as follows: （1）； in, , These are the moment of inertia and damping coefficient of the rotor tilt motor, respectively. The angle of the rotor tilt motor; This refers to the output torque of the tilt rotor motor; The electromagnetic torque of the tilt rotor motor; This is the input current for the rotor tilt motor; The electromagnetic torque coefficient of the rotor tilt motor; the subscripts i=1, 2, 3, 4 represent the first air-to-ground dual-mode tilt drive system, the second air-to-ground dual-mode tilt drive system, the third air-to-ground dual-mode tilt drive system, and the fourth air-to-ground dual-mode tilt drive system, respectively. 22) Establish the dynamic model of the rotor tilt reducer and tilt actuator as follows: （2）； in, , These are the moment of inertia and damping coefficient of the rotor tilt reducer and tilt actuator assembly, respectively. The tilt angle of the tilt actuator; The torque that the rotor tilt motor exerts on the tilt actuator through the rotor tilt reducer; The drag torque is caused by friction and gravity. The angle of the rotor tilt motor Tilting angle with tilt actuator The following relationship exists: （3）； in, The reduction ratio of the rotor tilt reducer; 23) The dynamic model of the rotor tilting system can be obtained from equations (1), (2), and (3) as follows: ； in, and These are the equivalent moment of inertia and equivalent damping coefficient of the rotor tilting system, respectively. , ; make , The state-space equations of the rotor tilting system can be obtained as follows: ； in, Let be the first state variable of the i-th rotor tilting system; Let be the second state variable of the i-th rotor tilting system.

8. The cooperative control method for the air-to-ground dual-mode fully linear motion control vehicle system according to claim 7, characterized in that, Step 3) is as follows: 31) Using the collected tilt angle and tilt angular velocity of the tilt actuator, the drag torque on the rotor tilt mechanism is observed. ,as follows: （4）； in, , They are respectively , Observed values; for Observed values; The base gain for tilt angle observation; For tilt angle observation error feedback gain; The base gain for tilt angular velocity observation; This is the gain for tilt angular velocity error feedback; 32) Design a multi-parameter coordinated adjustment mechanism to improve the observation accuracy of the nonlinear exponential state observer, as follows: ； in, ; ; Let be the observed error of the tilt angle of the tilt actuator in the i-th air-ground dual-mode tilt drive system. The tilt angular velocity observation error of the tilt actuator in the i-th air-ground dual-mode tilt drive system; for Maximum allowed value; for Dynamically adjustable gain; for The rate of change of gain is adjusted; for The rate of change of gain is adjusted; for Dynamically adjustable gain; for Auxiliary adjustment gain; for The coupling adjustment gain; for The rate of change adjusts the gain.

9. The cooperative control method for the air-to-ground dual-mode fully linear motion control vehicle system according to claim 8, characterized in that, Step 4) is as follows: 41) Based on the tilt target angle of the tilt actuator output in step 1), calculate the tilt angle coordination error of the tilt actuator in the i-th air-ground dual-mode tilt drive system. Error related to tilt angular velocity for: ； in, ; ; Let be the first state variable of the j-th rotor tilting system; Let j be the second state variable of the j-th rotor tilting system; the subscripts j=1, 2, 3, 4 represent the first air-to-ground dual-mode tilting drive system, the second air-to-ground dual-mode tilting drive system, the third air-to-ground dual-mode tilting drive system, and the fourth air-to-ground dual-mode tilting drive system, respectively. 42) The tilt angle coordination error of the tilt actuator in the i-th air-ground dual-mode tilt drive system. Differentiating with respect to time t yields the dynamic equation for the tilt angle cooperative error: （5）； 43) Differentiating equation (5) with respect to time t, we can obtain the following dynamic equation for the coordinated error of the tilt angular velocity of the tilt actuator in the i-th air-ground dual-mode tilt drive system: ； 44) Design a sliding surface that considers attitude coupling angle constraints, as follows: （6）； in, It is a sliding surface; For the integral term gain; This is the parameter of the first tilt angle error power; This is the second tilt angle error power parameter; The parameter is the power of the first attitude coupling angle error. The second attitude coupling angle error is a power parameter; t is the upper limit of integration. For integration variables; For attitude coupling angle error, ; Adjust the gain to account for attitude coupling angle error; The tilt angle coordination error of the tilt actuator in the j-th air-ground dual-mode tilt drive system; 45) Differentiating equation (6) with respect to time t yields: ； 46) Order , The equivalent control law of the i-th air-ground dual-mode tilt drive system is calculated. The expression is as follows: ； 47) Calculate the sliding mode control rate The expression is as follows: ； in, This is the gain coefficient; The parameter is adjusted by power. For attenuation adjustment parameters; 48) Using the observed drag torque and equivalent control law of the rotor tilting mechanism in the i-th air-to-ground dual-mode tilting drive system Sliding mode control rate The current control signal is calculated. ,as follows: ； 49) Based on the current control signal The rotor tilt motor drives the tilting actuator to control the tilting angle and tilting angular velocity.

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