38 results about "Generalized forces" patented technology

The invention discloses a multi-dimensional aeroelastic calculation method and device based on a nonlinear Euler-Bernoulli beam and a storage medium, and belongs to the technical field of wind turbine aerodynamics, the method comprises the following steps: inputting the stiffness of each section of a blade into a nonlinear Euler-Bernoulli beam equation to obtain a modal-displacement transformation matrix; the rigidity, the weight and the external force of each section of the blade are converted to obtain a generalized rigidity matrix, a generalized mass matrix and a generalized force; starting circulation, substituting into a forced coupling vibration equation, solving modal displacement of each order at the current moment, and inputting into a modal-displacement inverse transformation matrix to obtain blade displacement; the generalized force is substituted into a blade element momentum theoretical formula to solve aerodynamic force at the next moment, the generalized force is updated to obtain updated generalized force, and aerodynamic force at each moment is obtained; and calculating to obtain the multi-dimensional aerobomb. According to the method, the calculation of the blade deformation and the load considers the change of the torsional degree of freedom, and more accurate and more efficient load and deformation calculation can be carried out.

The invention provides a direct comprehensive modeling method for a helicopter tail rotor / tail beam coupled substructure, which comprises the following steps of: constructing a blade model, and dispersing the blade model to obtain a mass matrix, a rigidity matrix, a damping matrix and a generalized force vector expression of a single blade; establishing a structural kinetic equation of the tail beam; and finally, according to the displacement boundary condition of the joint of each paddle and the tail beam, converting the paddle structure dynamic equation, and assembling the rigidity matrix, the damping matrix, the mass matrix and the generalized force vector of each paddle after conversion with the rigidity matrix and the mass matrix of the tail beam respectively to obtain the structure dynamic equation of the tail rotor / tail beam coupling system. And establishing a structural dynamic model of the tail rotor / tail beam coupling system. The method is simple and reliable in modeling process and high in universality, is not limited by the distribution type of the tail rotor, can be applied to the non-uniformly distributed tail rotor, and provides a new thought for coupling analysis of the tail rotor / tail rotor and rotor wing / fuselage of the helicopter, dynamic characteristic solving of the tail rotor and analysis of stability.

The invention discloses a large flexible wing static aeroelasticity analysis method based on a physical information neural network, and belongs to the field of aircraft design. The method comprises the following steps: for the wing with the super-high aspect ratio, firstly, dispersing the wing into n spanwise sections based on a strip theory, and initializing a reference angle-of-attack parameter of each spanwise section; then, a physical information neural network (PINN) is built, unsteady flow field solving is carried out on each section, for the current ith iteration, the physical information neural network is used for sequentially traversing and extracting pressure distribution of the airfoil surface of each section, respective aerodynamic load distribution is calculated, and the generalized force of the airfoil is obtained; and solving a structural dynamics equation based on the generalized force and structural information of the wing, calculating the deformation of the large-deformation wing by using a modal rotation method, and finally, carrying out solving iterative circulation on aerodynamic force and structural deformation until the attack angle is converged, so as to obtain the actual lift force L of the wing. According to the method, the calculation precision and efficiency are remarkably improved, and different flight conditions and wing design can be adapted.

The invention discloses a rapid modeling method of a carrier rocket rigid-elastic-shake coupling model, which comprises the following steps of: establishing a motion equation of a carrier rocket: establishing a mass center motion equation of the carrier rocket according to a Newton's second law, establishing a motion equation around the mass center of the carrier rocket according to a moment of momentum theorem relative to the mass center, and simplifying the carrier rocket into a one-dimensional beam model; establishing an elastic vibration equation; solving force, torque and generalized force thereof; solving expressions of gravity, thrust, control force, engine swing inertia force, aerodynamic force, aerodynamic damping force, wind disturbance force, force, torque and generalized force thereof; propellant shaking is analyzed by adopting a spring-mass-damper equivalent model; propellant shaking equations in the pitching direction and the yawing direction of the carrier rocket are established, and inertia force, inertia moment and generalized force generated by propellant shaking are established; the obtained various forces, moments and generalized forces and inertia forces, inertia moments and generalized forces generated by shaking of a propellant are substituted into a motion equation of the carrier rocket to obtain a mass center motion equation, the motion equation of the rocket is around the mass center, and a six-degree-of-freedom nonlinear total dynamical model of the carrier rocket is established when the rocket tilts and tilts; elastic vibration equations in three directions of yawing and rolling are established; and solving the carrier rocket rigid-missile-shake coupling model. According to the method, rapid numerical simulation can be carried out on the carrier rocket rigid-missile-shake coupling model, the influence of a solving result on carrier rocket attitude change is analyzed, and a foundation is laid for navigation and attitude control design of the carrier rocket.

The present invention discloses a trajectory tracking method for a variable-load mobile manipulator based on reinforcement learning and model predictive control. First, a system model of the mobile manipulator established based on Lagrange's equation is obtained, and the dynamic equation is derived through the system kinetic energy, potential energy, and generalized force formulas. The model predictive control (MPC) module is based on this model, uses the discrete state equation to predict the future state, and obtains the control input by optimizing the cost function. The reinforcement learning (RL) module defines a specific state space, action space, and reward function, and trains the agent using the Q-learning algorithm. In the collaborative control stage, the weight coefficient is dynamically adjusted according to the system state, and the control inputs of MPC and RL are fused. The present invention effectively solves the problem of trajectory tracking of variable-load mobile manipulators, significantly improves the trajectory tracking accuracy, enhances the system adaptability and robustness, and has broad application prospects in the fields of industrial manufacturing, logistics warehousing, etc.

The invention discloses a part flexibility processing method and device, equipment and a storage medium, and relates to the technical field of multi-body power system dynamics, and the method comprises the steps: selecting a co-rotation node and a boundary point on a target part; establishing a mechanical behavior model according to the generalized displacement on the co-rotation node and the boundary point, and describing the relation between the displacement and the stress of the component by using the relation between the generalized displacement and the generalized force; discretizing the target part according to a preset continuous medium model to obtain discretized nodal displacement and nodal force and a mechanical behavior model described by a relationship between the nodal displacement and the nodal force; and the flexibility process is optimized through the equivalent relation between the generalized displacement and the nodal displacement and the equivalent relation between the generalized force and the nodal force. According to the scheme, the coordination effect of the co-rotation nodes and the boundary points and discretization modeling are combined, and the calculation process is optimized through the mechanical transfer relation between the nodes, so that the component deformation and motion analysis efficiency is improved while the component flexible calculation precision is ensured.

The present application belongs to the field of elastic motion modeling of air defense missiles, and particularly relates to an elastic motion modeling method for air defense missiles with trajectory control and direct-gas combined control, aiming at solving the problem that the traditional modeling method is insufficient in covering trajectory control force, thus being difficult to realize accurate modeling of the elastic motion of air defense missiles with trajectory control and direct-gas combined control. The present application comprises: calculating the kinetic energy T of the missile system caused by the bending deformation of the elastic missile body, the elastic potential energy U of the missile system, and the damping energy D of the missile system caused by the bending deformation of the elastic missile body; calculating the generalized force Q acting on the missile body corresponding to the virtual work through the virtual work principle i ; based on the kinetic energy T of the missile system, the elastic potential energy U of the missile system, the damping energy D of the missile system, and the generalized force Q i , constructing the dynamic equation of the elastic missile body through the Lagrange equation. The present application corrects and improves the problem of insufficient coverage of trajectory control force in the traditional modeling method, and has high accuracy and precision in the elastic motion modeling of air defense missiles with trajectory control and direct-gas combined control.

The present invention relates to the field of intelligent weaving technology, specifically to a core mold posture control method and system adapted to time-varying loads of weaving, the method comprising the following steps: establishing a core shaft end face coordinate system according to a main robot, and obtaining a coordinate system geometric relationship in combination with the coordinate system: establishing a core shaft center of mass generalized analysis model according to the relative motion relationship, coordinate system and geometric relationship of weaving; obtaining a rigid body dynamics model by combining the core shaft center of mass generalized analysis model and the yarn drop point stage, and analyzing the core mold center of mass generalized analysis results by the rigid body dynamics model to determine the input force required by the robot; constructing a dual-robot co-supporting core mold model, and obtaining the generalized force at the core mold center of mass according to the input force required by the robot and the dual-robot co-supporting core mold model; constructing a robot joint speed analytical model according to the generalized force at the core mold center of mass, and optimizing the robot control parameters using the analytical model. The present invention optimizes the parameters according to the execution force and weaving motion.

This invention belongs to the technical field of magnetic levitation motion control and conveying systems. It provides a method and system for real-time distribution of six-degree-of-freedom generalized forces in a magnetic levitation planar motor. First, a physical model of the magnetic levitation planar motor is established, and the real-time position coordinates of the mover in the stator coordinate system are obtained. A constraint coefficient matrix representing the balance of the six-degree-of-freedom generalized forces is constructed. A quadratic convex optimization projection model is used, with minimizing coil copper loss as the objective function and generalized force balance as the constraint condition. Based on the Lagrange multiplier method, the forces on each coil in the model are optimized to obtain the minimum force on each coil group at any position of the mover throughout its stroke, thereby reducing the coil current and achieving low power consumption for the six-degree-of-freedom motion of the mover. This invention has the advantages of low computational complexity, real-time processing of force distribution tasks at any position of the mover throughout its stroke, and effective reduction of system heat dissipation.

The application relates to the field of anti-swing technology of ship-mounted cranes, and discloses a ship-mounted crane anti-swing control method and system, which comprises the following steps: establishing a ship coordinate system and calculating the relative kinetic energy of the crane according to the ship coordinate system, adding inertial force to the generalized force of each degree of freedom, analyzing the dynamic model of the swing of the crane boom and the load, combining the RBF neural network model and the sliding mode control to construct adaptive sliding mode anti-swing control, analyzing the continuous uncertain upper bound disturbance existing in the under-actuated ship-mounted crane load based on the adaptive sliding mode anti-swing control, approximating the continuous disturbance of the uncertain upper bound, simplifying the dynamic model, introducing the backstepping sliding mode control to compensate the observation error of the nonlinear disturbance observer, judging the position of the load, and switching the LQR control and the adaptive sliding mode anti-swing control according to the judgment result. The application has the characteristics of good anti-swing control and dynamic adjustment.

The application discloses a robot joint reducer dynamics modeling method, device, equipment and medium, and relates to the technical field of transmission systems. The method comprises the following steps: acquiring double circular arc tooth profile parameters; obtaining multi-tooth meshing force distribution under different load conditions based on the double circular arc tooth profile parameters and a finite element method; calculating multi-tooth comprehensive meshing stiffness according to the multi-tooth meshing force distribution; establishing a multi-coordinate system framework during joint movement of an industrial robot; deducing an absolute acceleration expression of a harmonic reducer in a rotating non-inertial coordinate system based on the multi-coordinate system framework; constructing a generalized force excitation model according to the absolute acceleration expression; and establishing a harmonic reducer dynamics equation considering pose changes according to the multi-tooth comprehensive meshing stiffness and the generalized force excitation model. The method can more accurately predict transmission errors and dynamic responses of the harmonic reducer under high dynamic conditions.

The application discloses a kind of wheeled biped robot motion control method and system, comprising: model predictive controller is based on the motion control instruction of input and outputs the generalized force moment F that needs to be applied to trunk;Solving the distance Δx of the trunk centroid and wheel center point in x-axis direction of robot;Based on centrifugal force compensation strategy, calculate the trunk roll angle, based on terrain adaptation strategy, calculate the wheel position under the trunk coordinate system;After inverse kinematics is solved, the expected leg joint angle, leg joint speed and swing bar pitch angle are obtained as state input;Whole body controller is based on the generalized force moment F obtained by model predictive controller and the state input obtained by inverse kinematics solving, fusion dynamics feedforward and joint feedback, finally obtain the leg joint torque and wheel joint torque for controlling robot motion.The application enhances the robustness of robot when high-speed steering, to prevent rollover.

The invention provides a coupled six-degree-of-freedom elastic aircraft flight simulation method. The method comprises the following steps: step 1, modeling a kinematic equation of an aircraft; 2, according to the virtual work principle, modeling is conducted on a kinetic equation of the aircraft on the basis of the kinematic equation; 3, performing elastic correction on the airflow angle of the aircraft, and calculating aerodynamic force borne by the aircraft and corresponding aerodynamic torque according to the airflow angle subjected to elastic correction; calculating an external force, an elastic deformation generalized force and a moment borne by the aircraft; 4, substituting the external force, the torque and the elastic deformation generalized force borne by the aircraft into the kinetic equation in the step 2 to obtain a kinetic equation after elastic correction of the aircraft, and calculating flight parameters of the aircraft according to the kinetic equation so as to realize flight simulation of the aircraft; according to the method, flight simulation considering the aeroelastic effect and the rigid-elastic coupling effect at the same time can be achieved, and finally more accurate flight simulation is provided for the elastic aircraft.

The application provides a concrete vibration table parameter determination method based on a same-direction multi-machine self-synchronization, and specifically comprises the following steps: S1: obtaining kinetic energy, potential energy and a generalized force equation of the concrete vibration table according to a dynamic model of the concrete vibration table; S2: obtaining a motion differential equation of the concrete vibration table in combination with a Lagrange equation; S3: substituting an average phase angle, an angular velocity and an angular acceleration of an exciter into the motion differential equation of the concrete vibration table to obtain a dimensionless coupling equation of the concrete vibration table; S4: obtaining a synchronization condition in combination with the dimensionless coupling equation of the concrete vibration table and a limitation condition of an electromagnetic torque; and S5: obtaining a stability condition in combination with the dimensionless coupling equation of the concrete vibration table under the condition of meeting the synchronization condition. The method increases the vibration intensity of the multiple exciters in the concrete vibration table, thereby ensuring the vibration intensity of the concrete vibration table and improving the quality of the concrete prefabricated part.

The application discloses a kind of multi-robot formation tracking and obstacle avoidance control method under directed communication topology, belong to multi-robot system cooperative control technical field.It includes: constructing directed communication topology with virtual leader as root node, combining natural constraint and input geometric parameterization executor reachable acceleration affine set, construciton graph coupling formation tracking constraint, safety constraint between robot and environmental obstacle and safety constraint between following robot;Each constraint line is normalized according to fixed reference scale and weighted stacked;Minimum weighted norm least square input is directly calculated in reachable acceleration set, and whether task line can be accurately implemented is judged by compatibility condition.The application avoids that traditional U-K framework generates generalized force beyond the implementable force subspace of executor on underactuated platform.

The application discloses a soft robot arm length prediction method based on physical mechanism and RBFNN residual fusion. The method comprises the following steps: obtaining the cavity data of the flexible driving cavity of the soft robot arm, and then establishing a physical mechanism main model; inputting the real-time cavity length of the flexible driving cavity into the model, and inversely obtaining an experimental generalized force residual; constructing a dynamic feature vector and inputting the experimental generalized force residual into an RBFNN residual model to train a residual prediction function; fusing the generalized force residual prediction value and the physical mechanism main model to form a fusion dynamics model, and obtaining the length prediction trajectory of the soft robot arm by performing forward integration. The application retains the physical meaning of the model parameters, and compensates the unmodeled errors caused by the hysteresis of flexible materials, machine-fluid coupling, pressure dynamics and local loop effect through residual learning, so that the length prediction accuracy and model interpretability of the soft robot arm under various dynamic excitations can be improved.

The invention discloses a theoretical model for spiral self-feeding shape correction of a pipe, which comprises the following steps of: establishing a theoretical formula of total kinetic energy T of the pipe on the basis of a thin-wall hypothesis under the conditions that a rotating shaft of the pipe is assumed to coincide with a bent plane and axial rolling of the pipe is ignored; establishing a simplified theoretical formula of potential energy V of the pipe on the basis of a reciprocating bending unified curvature theorem and a bidirectional effect under the condition of neglecting plastic dissipation of the pipe; modeling is conducted on the movement track of the pipe on the basis of the Lagrange equation so as to obtain a movement track equation set, and the movement track equation set comprises a coupling relational expression among the circumferential bending angle of the pipe, the spiral azimuth angle of the pipe and the axial self-feeding displacement s; wherein the Lagrange equation is as follows: Qq is the generalized force applied to the pipe, L is the Lagrange quantity, and q is the generalized coordinate system and is a first derivative of q.

The embodiment of the invention provides a multi-body system control method, equipment and a medium. The method comprises the steps that a pre-trained generalized force estimation model is called, the predicted generalized force of the multi-body system is obtained according to the system state of the multi-body system at the current moment, and the generalized force estimation model is a model which is trained based on a physical information neural network in advance and predicts the generalized force borne by the system according to the system state; adopting a variational integrator to calculate the system state at the next moment according to the system state and the predicted generalized force; and outputting the system state at the next moment to an actuator of the multi-body system. The method is used for achieving the effects of improving the stability of a simulation process and the precision of a simulation result in a complex multi-body system dynamics analysis scene, and further improving the stability and the precision of multi-body system control.

The present application relates to a kind of drive-by-wire chassis key parameter active identification and control collaborative optimization method and system, for the low precision of parameter identification caused by insufficient regular driving excitation, and active excitation exists strong intervention, the problem of vehicle stability decline, establish the mapping relationship of target motion state and generalized force, construct the control distribution constraint of redundant actuator, realize the whole vehicle multi-objective motion control in the main space of constraint model, in the zero space, design the estimator of active enhancement of excitation condition, and using the orthogonality of main space and zero space, realize the collaborative optimization of control and estimation task through completely decoupled hierarchical control framework.For model uncertainty and zero space projection error, construct lumped disturbance compensation mechanism, improve the robustness of system under complex environment.The present application can quickly and accurately identify the key parameters of vehicle-road under the premise of not changing the trajectory and attitude of vehicle, ensure vehicle stability and trajectory tracking performance.

The present invention relates to a variable stiffness control method of a hydraulic leg SLIP model that can adapt to different rigidity grounds, which comprises the following steps: obtaining the leg stiffness in the Cartesian space z direction under different ground stiffnesses based on the series total stiffness; introducing the SLIP model to obtain the variable stiffness parameters of the SLIP model from the foot end to the center of mass; respectively constructing the stiffness relationship between the foot end and the generalized force and generalized position of the joint, deriving the mapping relationship between the foot end of the hydraulic leg and the joint equivalent stiffness, and obtaining the joint variable stiffness parameters; establishing the hydraulic leg SLIP model hydraulic cylinder variable stiffness parameters; finally combining the hydraulic leg SLIP model hydraulic cylinder variable stiffness parameters with the environmental variable stiffness parameters to realize variable stiffness control under different environmental stiffnesses. A set of complete corresponding relationships is obtained to obtain the joint to equivalent SLIP stiffness relationship formula, under which the active compliance parameters of the hydraulically driven joint can be accurately adjusted to realize the active variable stiffness control of the joint to adapt to different environmental stiffnesses.

The invention provides a novel dynamic modeling method for a fatigue loading device considering the action of a wind power blade, and aims to solve the problem of insufficient modeling precision caused by neglecting the coupling action of a large flexible wind power blade and the loading device in the prior art. The novel fatigue loading device is based on a two-degree-of-freedom 5R parallel robot, adopts a Lagrangian method to construct a kinetic model, and specifically comprises the following steps: analyzing the stress condition of the novel fatigue loading device, and selecting generalized coordinates; and calculating kinetic energy, potential energy and dissipated energy of the system, deducing generalized force corresponding to the generalized coordinates, substituting each energy parameter and the generalized force into a Lagrange equation, and simplifying to obtain a kinetic model. The model incorporates blade quality, rigidity and damping parameters, can accurately reflect dynamic behaviors of the novel fatigue loading device under actual fatigue test conditions, can be used for evaluating loading system performance, provides a basis for device structure optimization and control strategy design, and is suitable for the field of large-scale flexible wind power blade fatigue test.

The embodiment of the invention provides a software actuator control method and device, equipment and a storage medium, and relates to the technical field of software mechanical control. According to the method, generalized force of the software actuator is obtained at least based on geometric parameters and pressure parameters, axial strain parameters are obtained at least based on the geometric parameters, strain energy of the software actuator is obtained according to the axial strain parameters and the geometric parameters, and equivalent mass of the actuator in an execution environment is obtained. Gravitational potential energy and kinetic energy of the software actuator are obtained based on the equivalent mass, total potential energy is obtained by subtracting the strain energy and the gravitational potential energy from the kinetic energy, an initial Lagrangian model is constructed according to the total potential energy and generalized force, the initial Lagrangian model is simplified based on Taylor series expansion, and an equivalent Lagrangian model is obtained; and performing numerical solution on the equivalent Lagrange model according to a preset boundary condition to obtain control parameters of the software actuator. The model is simplified, the calculation efficiency is improved, and the motion control accuracy and real-time control are realized.

The invention relates to the technical field of wind resistance of engineering structures, in particular to a T-shaped tower generalized force spectrum calculation method based on an eccentricity effect, which comprises the following steps of: establishing numerical models of different geometric eccentricity rates, acquiring three-component force time-history data by adopting large eddy simulation, and combining with wind tunnel test verification to calculate a generalized force spectrum of a T-shaped tower. The influence rule of the eccentricity rate on aerodynamic characteristics and wind pressure distribution is systematically analyzed; a normalized force spectrum model is constructed based on fast Fourier transform and nonlinear fitting, the coupling effect of resistance, lift force and torque is quantified, and finally a generalized force spectrum expression considering the eccentricity rate influence is formed through the modal superposition principle. The three-component coupling effect systematic evaluation system for the eccentric T-shaped tower is established for the first time, the technical problem that flow field asymmetry and torque sudden change are difficult to accurately predict under the high eccentricity rate working condition is solved, collaborative analysis of downwind, crosswind and torsional wind loads is achieved, and the evaluation reliability of structural wind vibration response is remarkably improved.

The present invention proposes an adaptive control method and system for an aerial remote sensing two-axis stabilized platform based on the Kane method, and the method comprises the following steps: establishing a generalized coordinate system to derive the generalized speed, deflection speed and deflection angular speed corresponding to the aerial remote sensing two-axis stabilized platform; analyzing the generalized active force and generalized inertial force acting on the aerial remote sensing two-axis stabilized platform; bringing the obtained speed and generalized force into the equation of the Kane method to obtain the dynamic model of the aerial remote sensing two-axis stabilized platform; constructing a heading controller and a pitch controller respectively; the heading controller and the pitch controller are both adaptive controllers based on a PID controller; inputting the desired heading deflection angle and the desired pitch deflection angle, and realizing the control of the aerial remote sensing two-axis stabilized platform based on the dynamic model through the constructed heading controller and pitch controller. The present invention simplifies the modeling process of the aerial remote sensing two-axis stabilized platform and improves the control performance of the aerial remote sensing two-axis stabilized platform.

The invention provides a dynamics modeling method and device for a multi-axis steering multi-hinged vehicle, and the method comprises the steps: determining the motion freedom degree of the vehicle according to the structure of the multi-axis steering multi-hinged vehicle, and determining a generalized coordinate corresponding to the motion freedom degree of the vehicle; determining a dynamic coordinate system and vehicle parameters according to the generalized coordinates; determining the dynamic energy of the vehicle according to the generalized coordinates, the dynamic coordinate system and the whole vehicle parameters, and establishing a Lagrange equation by deriving the dynamic energy; external force borne by the vehicle is determined according to the generalized coordinates, the dynamic coordinate system and the whole vehicle parameters, and generalized force corresponding to the Lagrange equation is solved according to the external force and the virtual work principle; and establishing a vehicle dynamics model according to the generalized force and a Lagrange equation. According to the method, the precision and complexity of the vehicle dynamics model are effectively balanced, the model is high in interpretability and expansibility, the method can be used for model simulation analysis, the real vehicle test cost is reduced, and a model basis is provided for controller design.

The application discloses a kind of dynamic base mechanical arm end load mass online estimation method, belong to robot control technical field.The method of the application includes: the estimated value of load mass is handled to obtain six-dimensional virtual generalized force, six-dimensional pose feedback signal of trunk is collected and handled to obtain trunk actual stress, thrust and trunk actual stress are compared, the estimated value of current load mass is handled to obtain the estimated value of new load mass using load mass adaptive iterative speed sliding mode control model, until trunk actual stress and thrust are equal.The dynamic base mechanical arm end load mass online estimation method provided by the application can estimate the load at the end of the arm in real time based on the dynamic base thrust constructed and applied based on the current parameters and the actual thrust prediction value of the trunk to adjust the controller model parameters and improve the system control performance.

The application discloses a robot joint reducer dynamics modeling method, device, equipment and medium, and relates to the technical field of transmission systems. The method comprises the following steps: acquiring double circular arc tooth profile parameters; obtaining multi-tooth meshing force distribution under different load conditions based on the double circular arc tooth profile parameters and a finite element method; calculating multi-tooth comprehensive meshing stiffness according to the multi-tooth meshing force distribution; establishing a multi-coordinate system framework during joint movement of an industrial robot; deducing an absolute acceleration expression of a harmonic reducer in a rotating non-inertial coordinate system based on the multi-coordinate system framework; constructing a generalized force excitation model according to the absolute acceleration expression; and establishing a harmonic reducer dynamics equation considering pose changes according to the multi-tooth comprehensive meshing stiffness and the generalized force excitation model. The method can more accurately predict transmission errors and dynamic responses of the harmonic reducer under high dynamic conditions.

This invention discloses a theoretical model for spiral self-feeding straightening of pipes, including, under the assumption that the rotation axis of the pipe coincides with the bending plane and axial roll of the pipe is ignored, establishing the total kinetic energy of the pipe based on the thin-wall assumption. T The theoretical formula is derived; neglecting the plastic dissipation of the pipe, a simplified potential energy model for the pipe is established based on the unified curvature theorem of reciprocating bending and the bidirectional effect. V The theoretical formula is used to model the motion trajectory of the pipe based on the Lagrange equation, thereby obtaining a set of motion trajectory equations. These equations include the circumferential bending angle of the pipe, the helical azimuth angle of the pipe, and the axial self-feed displacement. s The coupling relationship between them; where the Lagrange equation is, Q q For the generalized forces acting on the pipe, L For Lagrange units, q For a generalized coordinate system, , for q The first derivative.

The application provides a new fatigue loading device dynamics modeling method considering the action of a wind power blade, and aims to solve the problem of insufficient modeling accuracy caused by ignoring the coupling action of a large flexible wind power blade and a loading device in the prior art. The new fatigue loading device is based on a 2-DOF 5R parallel robot, and a dynamics model is constructed by using the Lagrange method, and the specific steps include: analyzing the stress condition of the new fatigue loading device, selecting generalized coordinates; calculating the kinetic energy, potential energy and dissipation energy of the system, deducing the generalized force corresponding to the generalized coordinates, substituting the energy parameters and the generalized force into the Lagrange equation, and simplifying to obtain the dynamics model. The model includes the mass, stiffness and damping parameters of the blade, can accurately reflect the dynamic behavior of the new fatigue loading device under actual fatigue test working conditions, can be used for evaluating the performance of the loading system, can provide a basis for device structure optimization and control strategy design, and is suitable for the field of large flexible wind power blade fatigue testing.

The present application relates to the field of offshore floating platform safety assessment, and discloses a method, system, medium and equipment for inverting QTF based on multi-source response data, comprising: collecting multi-source response data of a mooring platform in a pool test; establishing a mooring dynamics model consistent with the pool test, taking the six-degree-of-freedom motion response of the platform as input to solve the mooring dynamics model to obtain the dynamic tension of each mooring cable, checking the mooring dynamics model and calculating the instantaneous generalized force of the mooring system acting on the platform; based on the six-degree-of-freedom time-domain motion equation of the platform, using the platform acceleration response, the instantaneous generalized force and the preset hydrodynamic parameters to invert the environmental load acting on the platform; based on the incident wave height time history and the environmental load, extracting the equivalent low-frequency slow-drift environmental load component, and using the cross-bispectrum analysis method to identify the second-order difference frequency transfer function matrix. The present application can improve the accuracy of mooring floating platform low-frequency slow-drift load identification.