Tilt rotor dynamics simulation method based on multi-body dynamics

Abstract

The invention discloses a tilt rotor dynamics simulation method based on multi-body dynamics, and relates to the field of aircraft dynamics modeling and simulation technology.The tilt rotor dynamics simulation method comprises the steps that a modular system comprising an input module, an output module, a machine body module, a propeller module, a connecting mechanism module and a dynamics solving module is constructed, each propeller in the propeller module is independently modeled as a rigid body, and the connecting mechanism module is used for modeling an active actuation hinge between a rotor wing and a machine body through rigid connection; performing dynamic modeling on the system by adopting a Kane method, and forming a system motion equation by constructing partial velocity expressions and inertia force forms of all parts; and carrying out numerical integral solution on the motion equation by utilizing a solver in a Simulink environment. The method has the advantages that the gyroscope coupling effect can be accurately described, the rapid change of a multi-rotor configuration is supported, comprehensive part-level mechanical data output is provided, and the simulation fidelity and the engineering application value are improved.

Description

Technical Field

[0001] The present invention relates to the field of aircraft dynamics modeling and simulation technology, and in particular to a tiltrotor dynamics simulation method based on multi-body dynamics. Background Art

[0002] With the rapid development of urban air mobility and electric vertical take-off and landing (EVTL) aircraft, tiltrotor configurations are becoming increasingly popular. By tilting the rotors from a vertical to a horizontal position, they enable a smooth transition from hovering to cruising flight, balancing the vertical maneuverability of rotorcraft with the high-speed range of fixed-wing aircraft. Currently, the 6-DOF rigid-body model, based on Newton-Euler mechanics, is widely used in engineering to describe the overall position and velocity of an aircraft. However, for tiltrotor configurations with multiple rotors and complex coupled actuators, there are no publicly available Cain method modeling implementations for tiltrotor eVTOLs. In particular, there is a lack of modular modeling solutions for Simulink. This not only results in a lack of modularity, making it difficult to adapt to different configurations and rapid changes in component count, but also lacks the ability to output component-level mechanical data (such as hinge torque and motor load). This also inadequately handles coupled gyroscopic effects, limiting the control law's ability to respond to nonlinear phenomena. Furthermore, incomplete modeling of non-inertial reference frames affects the physical accuracy and consistency of attitude solutions. Summary of the Invention

[0003] In order to solve the above technical problems, a tilt-rotor dynamics simulation method based on multi-body dynamics is provided. This technical solution solves the problems raised in the above background technology, such as the inability to accurately describe the gyroscopic coupling effect of the tilt-rotor aircraft during the tilting of the propeller disc, the lack of modular structure and the ability to output component-level mechanical data, which limits the control law's response ability to nonlinear phenomena and the practical application value of the simulation model.

[0004] In order to achieve the above objects, the technical solution adopted by the present invention is: A tiltrotor dynamics simulation method based on multi-body dynamics, comprising: Construct a modular system including an input module, an output module, an airframe module, a propeller module, a connection mechanism module, and a dynamics solution module. The airframe module has six generalized coordinates for describing the three-axis position and attitude angle of the main structure of the aircraft. Each propeller in the propeller module is independently modeled as a rigid body with two generalized coordinates: the propeller rotation angle and the propeller shaft tilt angle. The connection mechanism module models the active actuation hinge between the rotor and the airframe through a rigid connection. The dynamics solution module constructs the system dynamics equations based on the Kane method. The input module receives the control variables output by the flight control law, and the output module outputs generalized velocity derivatives, attitude data, motor drive torque, and tilt axis load torque. The Kane method is used to model the system's dynamics. By constructing partial velocity expressions and inertial force forms for each component, the system's motion equations are formed based on the D'Alembert principle. The motion equations are numerically integrated and solved using a solver in the Simulink environment.

[0005] Preferably, the modular system construction includes: In the initialization phase, the structural topology, mass properties, inertia tensors, and initial states of all components are defined; Coordinate setting: assign generalized coordinates and speed variables to each module and build coordinate transformation relationships; Kinematic modeling, using vector analysis methods to calculate the speed and acceleration of each component and construct partial velocity expressions; Dynamic modeling, projecting external forces, gravity, and inertial forces into various generalized directions to generate generalized force vectors; Assemble the dynamic equations, calculate the difference between the inertial force and the external force, and generate the Kane equations by taking the dot product of each generalized velocity; Solve and integrate: Input the equation into the Simulink solver and iteratively update the system state; Data output, records the dynamic response variables of each component.

[0006] Preferably, the generalized coordinates of the body module are defined as three-axis positions and attitude angles, and its mass attributes and inertia tensors are set in the initialization stage. The attitude angles include roll φ, pitch θ, and yaw ψ.

[0007] Preferably, the rotational freedom of the propeller module is controlled by the corresponding motor drive, and the tilting freedom is controlled by the corresponding servo actuation, and its inertia tensor is used to automatically generate the cross product of the propeller rotation angular velocity and the tilting angular velocity to model the gyroscopic coupling effect and reflect it in the roll and yaw response of the body.

[0008] Preferably, the connection mechanism module is modeled by an active actuating hinge to explicitly output the force exerted by the propeller on the fuselage and the tilt axis load torque.

[0009] Preferably, the output module provides motor shaft driving torque, tilting mechanism load torque and component connection point reaction force data.

[0010] Preferably, the numerical stability measures adopted in the numerical integration solution specifically include: Set limiters on state variables to prevent numerical divergence; Standardize some speed expressions; Use a high-stability ODE solver and configure a fixed step size for integration.

[0011] Preferably, the scalability supported by the system architecture specifically includes: Add any number of propeller modules without modifying the overall framework; Adapt to symmetrical or asymmetrical configurations; Integrate other rigid body modules and connect with existing control law modules.

[0012] Compared with the prior art, the present invention has the following beneficial effects: The present invention proposes a tilt-rotor dynamics simulation method based on multi-body dynamics. By implementing the Kane method in a modular form in the Simulink environment, a system including an input module, an output module, a body module, a propeller module, a connection mechanism module and a dynamic solution module is constructed. Each module is independently modeled with clear generalized coordinates and degree of freedom definitions. That is, without modifying the overall framework, any number of propeller modules can be added, adapting to symmetrical or asymmetrical configurations, integrating other rigid body modules and docking with existing control law modules. It can also accurately describe the gyroscopic coupling effect during the tilting of the propeller disc, avoiding the problem that the traditional 6-DOF model cannot truly reflect the roll or yaw coupling phenomenon in the control law. At the same time, it also supports multiple engineering links such as subsequent aircraft control law design, structural load analysis, actuator life assessment, etc., thereby enhancing the practical application value of the simulation model. The present invention proposes a tiltrotor dynamics simulation method based on multi-body dynamics. By explicitly outputting the motor shaft driving torque, tilt mechanism load torque and component connection point reaction force data in the system and adopting a series of numerical stability measures in the numerical integration solution process, the motor shaft driving torque, tilt mechanism load torque and component connection point reaction force data can be explicitly output, supporting structural life assessment and drive design, providing comprehensive component-level mechanical data output capabilities, and ensuring high precision and high stability of the simulation process by setting a limiter, standardization processing and using a high-stability ODE solver, avoiding numerical divergence and error accumulation problems, and providing high-precision simulation results, providing reliable technical support for the design, control and optimization of aircraft, and improving the practical application value of the simulation model. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a schematic diagram of the process of the present invention; Figure 2 A schematic diagram of the process of constructing the modular system in the present invention; Figure 3 A flow chart of the numerical stability measures used in the numerical integral solution of the present invention; Figure 4 A flow chart illustrating the scalability supported by the system architecture of the present invention. DETAILED DESCRIPTION

[0014] The following description is intended to disclose the present invention so that those skilled in the art can implement the present invention. The preferred embodiments described below are merely examples, and those skilled in the art may conceive of other obvious variations.

[0015] Reference Figure 1 As shown, a tiltrotor dynamics simulation method based on multi-body dynamics includes: Construct a modular system including an input module, an output module, an airframe module, a propeller module, a connection mechanism module, and a dynamics solution module. The airframe module has six generalized coordinates for describing the three-axis position and attitude angle of the main structure of the aircraft. Each propeller in the propeller module is independently modeled as a rigid body with two generalized coordinates: the propeller rotation angle and the propeller shaft tilt angle. The connection mechanism module models the active actuation hinge between the rotor and the airframe through a rigid connection. The dynamics solution module constructs the system dynamics equations based on the Kane method. The input module receives the control variables output by the flight control law, and the output module outputs generalized velocity derivatives, attitude data, motor drive torque, and tilt axis load torque. The Kane method is used to model the system's dynamics. By constructing partial velocity expressions and inertial force forms for each component, the system's motion equations are formed based on the D'Alembert principle. The motion equations are numerically integrated and solved using a solver in the Simulink environment.

[0016] First, in the initialization phase, the structural topology, mass properties, inertia tensors, and initial states of all components are defined. Then, generalized coordinates and velocity variables are assigned to each module, and a coordinate transformation relationship is constructed. Secondly, the velocity and acceleration of each component are calculated through vector analysis methods, and partial velocity expressions are constructed. External forces, gravity, and inertia forces are projected into various generalized directions to generate generalized force vectors. Then, according to the Kane method, the difference between the inertia force and the external force is calculated. The dot product of each generalized velocity is calculated to generate the Kane equations. The equations are input into the Simulink solver, and the system state is iteratively updated. Finally, the dynamic response variables of each component are recorded. In the process of numerical integration solution, measures such as setting limiters for state variables, standardizing some speed expressions, using high-stability ODE solvers and configuring fixed step sizes for integration are adopted to ensure numerical stability. Therefore, it can be constructed through a modular system, supporting the addition of any number of propeller modules without modifying the overall framework, adapting to symmetrical or asymmetrical configurations, integrating other rigid body modules and docking with existing control law modules, which significantly improves the scalability and adaptability of the system. The Kane method is used for dynamic modeling, which can accurately describe the gyroscopic coupling effect during the tilting of the propeller disc, avoiding the traditional 6-degree-of-freedom model in the control law. The problem of being unable to truly reflect the roll or yaw coupling phenomenon in the simulation is solved. The explicit output of the motor shaft drive torque and the tilt axis load torque supports structural life assessment and drive design, provides comprehensive component-level mechanical data output capabilities, and is efficiently solved in the Simulink environment. It supports subsequent aircraft control law design, structural load analysis, actuator life assessment and other engineering links, thereby enhancing the practical application value of the simulation model, thereby constructing a modular system including input module, output module, body module, propeller module, connection mechanism module and dynamic solution module, realizing high-fidelity dynamic simulation of tiltrotor aircraft.

[0017] Reference Figure 2 As shown, the modular system construction includes: In the initialization phase, the structural topology, mass properties, inertia tensors, and initial states of all components are defined; Coordinate setting: assign generalized coordinates and speed variables to each module and build coordinate transformation relationships; Kinematic modeling, using vector analysis methods to calculate the speed and acceleration of each component and construct partial velocity expressions; Dynamic modeling, projecting external forces, gravity, and inertial forces into various generalized directions to generate generalized force vectors; Assemble the dynamic equations, calculate the difference between the inertial force and the external force, and generate the Kane equations by taking the dot product of each generalized velocity; Solve and integrate: Input the equation into the Simulink solver and iteratively update the system state; Data output, records the dynamic response variables of each component.

[0018] During the initialization phase, the system defines the structural topological relationships, mass properties, inertia tensors, and initial states of all components, providing basic data support for subsequent modeling, ensuring simulation errors caused by inaccurate parameters, and improving the physical accuracy of the model. Next, in the coordinate setting phase, generalized coordinates and velocity variables are assigned to each module, and coordinate transformation relationships are constructed so that the motion state of each component can be described and analyzed in a unified coordinate system.

[0019] In the kinematic modeling stage, vector analysis methods are used to calculate the velocity and acceleration of each component, and to construct partial velocity expressions, which provides the necessary kinematic basis for dynamic modeling.

[0020] During the dynamic modeling phase, the system projects external forces, gravity, and inertial forces into various generalized directions to generate generalized force vectors, ensuring that all forces acting on the aircraft can be accurately considered and calculated.

[0021] The dynamic equation assembly phase calculates the difference between the inertial force and the external force and takes the dot product of each generalized velocity to generate the Kane equations. This allows for efficient construction of the system's dynamic equations based on the Kane method. The solution and integration phase inputs the equations into the Simulink solver, iteratively updating the system state to achieve numerical simulation of the aircraft's dynamic behavior.

[0022] The data output stage records the dynamic response variables of each component, providing detailed data support for subsequent analysis and design.

[0023] The generalized coordinates of the body module are defined as three-axis positions and attitude angles. Its mass properties and inertia tensors are set during the initialization phase. The attitude angles include roll φ, pitch θ, and yaw ψ.

[0024] The generalized coordinates of the airframe module are defined as three-axis positions and attitude angles. These three-axis positions include the x, y, and z coordinates, while the attitude angles include the roll angle φ, pitch angle θ, and yaw angle ψ. This allows the airframe module to comprehensively describe the position and attitude changes of the aircraft in space, providing a foundation for subsequent dynamic modeling. Simultaneously, during the initialization phase, the system's mass properties and inertia tensors are set. These parameters are key factors in describing the aircraft's dynamic characteristics and directly affect its response characteristics under different motion states.

[0025] During the assembly process, the initial position and initial attitude angles along the three axes must be determined based on the actual physical characteristics of the aircraft. These initial conditions provide a starting point for subsequent simulations. Next, the mass properties and inertia tensors are set based on the actual mass and distribution of the aircraft. The accuracy of these parameters directly impacts the accuracy of the dynamic model. This ensures that the airframe module accurately reflects the aircraft's motion in space, including translational and rotational motion.

[0026] During the implementation process, the generalized coordinates and physical properties of the airframe module were integrated into the entire dynamics simulation system, interacting with other modules (such as the propeller module and the joint mechanism module). This enabled the airframe module to not only describe its own motion state but also work in conjunction with other modules to simulate the overall dynamic behavior of the aircraft.

[0027] The generalized coordinate definition of the airframe module, by introducing the definition of three-axis positions and attitude angles, enables a more comprehensive description of the aircraft's motion, avoiding the incomplete descriptions that can occur in traditional methods. Furthermore, the precise setting of mass attributes and inertia tensors enables the dynamic model to more accurately reflect the actual physical characteristics of the aircraft, improving the accuracy and reliability of the simulation. These improvements enable the method of this invention to provide higher simulation accuracy and greater engineering application value when addressing complex tiltrotor aircraft dynamics.

[0028] The propeller module's rotational freedom is controlled by the corresponding motor drive, and its tilting freedom is controlled by the corresponding servo actuation. Its inertia tensor is used to automatically generate a cross product of the propeller's rotational angular velocity and the tilting angular velocity to model the gyroscopic coupling effect and reflect it in the body's roll and yaw responses.

[0029] When a propeller tilts, its rotational inertia produces a gyroscopic effect around the tilt axis. This effect directly affects the aircraft's attitude changes, thereby more realistically reflecting the impact of the propeller motion on the aircraft's overall dynamic behavior. In modeling the gyroscopic coupling effect, by calculating the cross product of the angular velocity, we can accurately simulate the gyroscopic torque generated by the propeller during high-speed rotation and tilting. This torque has a significant impact on the aircraft's roll and yaw responses.

[0030] The propeller's autorotation is achieved by the motor through precise speed control, while the tilt motion is achieved by the servo through angle control. Independent control not only improves the system's flexibility but also enables the precise modeling and simulation of each propeller's motion. During its operation, the independently controlled autorotation and tilt degrees of freedom enable precise modeling of each propeller's motion, avoiding the potential simplification or neglect of certain degrees of freedom found in traditional methods. At the same time, the modeling method of automatically generating gyroscopic coupling effects from the inertia tensor can more realistically reflect the impact of propeller motion on the aircraft's attitude, improving the accuracy and reliability of the simulation model. This can help engineers more accurately predict and evaluate the aircraft's dynamic behavior under different flight conditions, thereby improving the aircraft's performance and safety.

[0031] The connection mechanism module is modeled by an active actuating hinge, and explicitly outputs the force exerted by the propeller on the fuselage and the load torque of the tilt axis.

[0032] The joint mechanism module models the active hinge between the rotor and the fuselage through a rigid connection. This module explicitly outputs the propeller's force on the fuselage and the tilt-axis load torque, providing more accurate and comprehensive data support for the vehicle's dynamic simulation. During its construction, the module first needs to define the connection points and connection methods between the rotor and the fuselage. By assuming a rigid connection, the module simplifies complex flexible connection problems, making the modeling process more intuitive and easier to handle. Next, the module calculates the propeller's force on the fuselage based on the propeller's motion. These forces, including thrust and torque, directly affect the fuselage's motion. The module also calculates the tilt-axis load torque, which is generated by the propeller's tilting motion and directly affects the tilt-axis load. This allows for a more accurate capture of the interaction between the propeller and the fuselage, avoiding the simplification or omission of key factors that may exist in traditional methods.

[0033] This allows the mechanism module to update the propeller force on the aircraft and the tilt axis load torque in real time through the calculation of the dynamic equations, reflecting the impact of the propeller movement on the aircraft in real time, making the simulation results more realistic and reliable, and providing more accurate data support for the dynamic simulation of the aircraft.

[0034] The output module provides motor shaft driving torque, tilt mechanism load torque and component connection point reaction force data.

[0035] The output module is tightly integrated with other modules in the system, such as the airframe module, propeller module, and joint mechanism module. The airframe and propeller modules use kinematic and dynamic modeling to calculate the motion and forces acting on each component. The joint mechanism module, through rigid connection modeling, calculates the propeller force acting on the airframe and the tilt axis load torque. This data is then transferred to the output module for aggregation and processing, providing data on the motor shaft drive torque, tilt mechanism load torque, and component connection point reaction forces.

[0036] During actual use, the output module first receives relevant mechanical data from each module, including motor shaft drive torque, tilt mechanism load torque, and component connection point reaction force, etc. The output module then organizes and formats this data for subsequent analysis and use. The output module also has data recording and storage functions, which can record the dynamic response variables generated during the simulation process for subsequent control law adjustment, structural design analysis, etc. At the same time, the data output of the output module is highly accurate and real-time, and can truly reflect the mechanical response of the aircraft in various flight states, providing reliable data support for engineering design. In addition, the output module is designed with good scalability and compatibility, which can be easily integrated with other systems and tools, further enhancing its value in engineering applications.

[0037] Reference Figure 3 As shown, the numerical stability measures adopted in the numerical integration solution specifically include: Set limiters on state variables to prevent numerical divergence; Standardize some speed expressions; Use a high-stability ODE solver and configure a fixed step size for integration.

[0038] First, by limiting the range of state variables during the simulation process, we can prevent variable values ​​from being too large or too small due to accumulated numerical errors, thereby preventing distortion and divergence of the simulation results. This completes the process of setting limiters on state variables to prevent numerical divergence. Setting limiters effectively improves the robustness of the simulation, avoiding numerical divergence and error accumulation. This significantly improves the stability of the simulation, especially when dealing with strongly nonlinear systems and fast dynamic responses.

[0039] Secondly, by normalizing some velocity expressions, the rounding error and cumulative error in the numerical calculation are reduced, thereby improving the accuracy and stability of the numerical calculation, achieving the effect of standardizing some velocity expressions, making it more adaptable to systems with high dynamic range and high frequency changes, and effectively avoiding simulation result deviations caused by numerical errors.

[0040] Finally, a high-stability ODE solver with a fixed step size was used for integration. High-stability ODE solvers (such as ode15s) excel at handling stiff systems and can effectively handle strong stiffness and rapidly changing dynamic characteristics. Configuring a fixed step size for integration further improves the stability and accuracy of the numerical calculations, avoiding the accumulation of numerical errors caused by variable step sizes. This allows the simulation process to achieve high-precision results while maintaining computational efficiency.

[0041] The comprehensive application of the above measures enables the present invention to provide high-precision and high-stability simulation results in the dynamic simulation of tilt-rotor aircraft, providing reliable technical support for the design, control and optimization of the aircraft.

[0042] Reference Figure 4 As shown, the scalability supported by the system architecture specifically includes: Add any number of propeller modules without modifying the overall framework; Adapt to symmetrical or asymmetrical configurations; Integrate other rigid body modules and connect with existing control law modules.

[0043] First, any number of propeller modules can be added without modifying the overall framework. This allows the system to flexibly adapt to different propeller configuration requirements. Whether increasing or decreasing the number of propellers, no changes to the overall system architecture are required. This greatly improves the system's adaptability and flexibility, allowing it to easily meet the needs of a variety of aircraft designs.

[0044] Secondly, the system architecture is adaptable to both symmetrical and asymmetrical configurations. Whether it's a traditional symmetrical configuration or a more complex asymmetric configuration, the system can be adapted through a modular design. This allows the system to be applied to a variety of tiltrotor aircraft types, meeting diverse design requirements. This provides greater design freedom without sacrificing performance.

[0045] Furthermore, the system architecture supports the integration of other rigid body modules and can be integrated with existing control law modules. This allows the system to handle not only rotor and airframe dynamics simulation but also other rigid body simulations, such as suspension arms and payload bays. By integrating with the control law modules, seamless integration from dynamics simulation to control law design is achieved, providing comprehensive support for overall aircraft design and optimization.

[0046] Furthermore, through modular design, each functional module is separated, allowing each module to be independently developed, tested, and integrated. This not only improves system development efficiency but also reduces system maintenance costs. During implementation, standardized interfaces and data exchange methods ensure efficient collaboration between modules.

[0047] In summary, the advantages of the present invention are: by constructing partial velocity expressions and inertial force forms for each component, the system motion equations are formed according to the d'Alembert principle, which can be efficiently solved in the Simulink environment, supporting subsequent multiple engineering links such as aircraft control law design, structural load analysis, and actuator life assessment.

[0048] The above shows and describes the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions merely illustrate the principles of the present invention. Various changes and modifications may be made to the present invention without departing from the spirit and scope of the present invention. Such changes and modifications are intended to fall within the scope of the present invention. The scope of protection claimed by the present invention is defined by the appended claims and their equivalents.

Claims

1. A tiltrotor dynamics simulation method based on multi-body dynamics, characterized in that: include: Construct a modular system including an input module, an output module, an airframe module, a propeller module, a connection mechanism module, and a dynamics solution module. The airframe module has six generalized coordinates for describing the three-axis position and attitude angle of the main structure of the aircraft. Each propeller in the propeller module is independently modeled as a rigid body with two generalized coordinates: the propeller rotation angle and the propeller shaft tilt angle. The connection mechanism module models the active actuation hinge between the rotor and the airframe through a rigid connection. The dynamics solution module constructs the system dynamics equations based on the Kane method. The input module receives the control variables output by the flight control law, and the output module outputs generalized velocity derivatives, attitude data, motor drive torque, and tilt axis load torque. The Kane method is used to model the system's dynamics. By constructing partial velocity expressions and inertial force forms for each component, the system's motion equations are formed based on the D'Alembert principle. The motion equations are numerically integrated and solved using a solver in the Simulink environment.

2. The tiltrotor dynamics simulation method based on multi-body dynamics according to claim 1, characterized in that: The modular system construction includes: In the initialization phase, the structural topology, mass properties, inertia tensors, and initial states of all components are defined; Coordinate setting: assign generalized coordinates and speed variables to each module and build coordinate transformation relationships; Kinematic modeling, using vector analysis methods to calculate the speed and acceleration of each component and construct partial velocity expressions; Dynamic modeling, projecting external forces, gravity, and inertial forces into various generalized directions to generate generalized force vectors; Assemble the dynamic equations, calculate the difference between the inertial force and the external force, and generate the Kane equations by taking the dot product of each generalized velocity; Solve and integrate: Input the equation into the Simulink solver and iteratively update the system state; Data output, records the dynamic response variables of each component.

3. The tiltrotor dynamics simulation method based on multi-body dynamics according to claim 2, characterized in that: The generalized coordinates of the body module are defined as three-axis positions and attitude angles. Its mass properties and inertia tensors are set during the initialization phase. The attitude angles include roll φ, pitch θ, and yaw ψ.

4. The tiltrotor dynamics simulation method based on multi-body dynamics according to claim 3, characterized in that: The propeller module's rotational freedom is controlled by the corresponding motor drive, and its tilting freedom is controlled by the corresponding servo actuation. Its inertia tensor is used to automatically generate a cross product of the propeller's rotational angular velocity and the tilting angular velocity to model the gyroscopic coupling effect and reflect it in the body's roll and yaw responses.

5. The tiltrotor dynamics simulation method based on multi-body dynamics according to claim 4, characterized in that: The connection mechanism module is modeled by an active actuating hinge, and explicitly outputs the force exerted by the propeller on the fuselage and the load torque of the tilt axis.

6. The tiltrotor dynamics simulation method based on multi-body dynamics according to claim 5, characterized in that: The output module provides motor shaft driving torque, tilt mechanism load torque and component connection point reaction force data.

7. The tiltrotor dynamics simulation method based on multi-body dynamics according to claim 6, characterized in that: The numerical stability measures adopted in the numerical integration solution specifically include: Set limiters on state variables to prevent numerical divergence; Standardize some speed expressions; Use a high-stability ODE solver and configure a fixed step size for integration.

8. The tiltrotor dynamics simulation method based on multi-body dynamics according to claim 7, characterized in that: The scalability supported by the system architecture specifically includes: Add any number of propeller modules without modifying the overall framework; Adapt to symmetrical or asymmetrical configurations; Integrate other rigid body modules and connect with existing control law modules.

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