90 results about "Rigid body dynamics" patented technology

The invention provides a dynamics performance parameter optimizing method of a high-speed train, relates to the field of parameter design optimizing based on the dynamics simulation analysis of the high-speed train, and aims at effectively replacing a dynamics simulation model of the high-speed train by a comprehensive target neural network agent model and combining the design analysis and the multi-target optimization algorithm of the high-speed train in the multi-disciplinary field to analyze and optimize the dynamics simulation approximation model of the high-speed train. The method specifically comprises the steps of building a multi-rigidity dynamics simulation model for the high-speed train; determining related important input/ output design spaces; selecting sampling strategy to obtain a design space sample set suitable for the dynamics performance analysis of the high-speed train; improving the generalization accuracy of the comprehensive target neural network by the bayesian regularization method; adjusting the number of nodes in a hidden layer to build the comprehensive target neural network agent network model of which the error is controlled to be within a certain of range; performing multi-target optimization through the intelligent differential evolution algorithm by using the improved comprehensive target neural network agent network model to obtain the optimized high-speed train design parameters. The method is mainly applied to the dynamics analysis and design optimization of the high-speed train.

The invention discloses an elastic body aircraft adaptive constrained tracking control indirect method. The objective of the invention is to solve the technical problem of low possibility of realizing adaptive tracking of reference instruction signals when an elastic body aircraft has input and state saturation constraints. The method includes the following steps that: a feedforward system is designed based on an instruction former, and tracked signals and the pulses of the former are subjected to convolution, so that new forming signals can be obtained and are adopted as the input of a subsequent feedback system; the design of the feedback system is decomposed into a velocity subsystem, a height subsystem and an elasticity subsystem, and the influence of elastic modality in rigid body dynamic is considered as elastic interference, and uncertain parameters and an external disturbance introduction nominal model are used in combination, and therefore, a controlled system can be obtained; and a saturation constrained adaptive control method can be realized for the controlled system through utilizing an instruction filter and an auxiliary system, and tracking for the forming signals in the feedforward system can be realized, and closed-loop system signals can be uniformly and ultimately bounded, and suppression on elastic modality deformation and vibration can be realized.

The invention provides a walking motion planning method for a biped walking robot. The walking motion planning method takes an omnidirectional moving trolley as a model, takes a condition that the trolley does not overturn as a dynamics constraint condition, considers the dynamics constraints in footprint transform, uses a three-dimensional linear inverted pendulum model between partial discrete footprints, generates a hip trajectory online, and obtains driving joint trajectories through inverse kinematics; and finally, the walking motion planning method adopts a multi-rigid-body dynamics model, adopts a ZMP theory to determine stability, verifies the effectiveness of the joint trajectories, optimizes parameters of the omnidirectional moving trolley and the three-dimensional linear inverted pendulum model, and finally realizes biped walking robot walking motion planning constrained by dynamics under a fast walking condition.

Computer simulation of the dynamics of rigid bodies interacting through collisions, stacks and joints is performed using a constraint-based system in which constraints are defined in terms of the positions of the bodies.

The invention provides a method for optimizing performance parameters of a movement mechanism of electronic equipment, which comprises the following steps: performing three-dimensional modeling on theelectronic equipment; respectively establishing a multi-rigid-body dynamic model and a rigid-flexible coupling multi-body model based on the established three-dimensional model of the electronic equipment; adopting a virtual prototype method to obtain the dynamic errors of the models; and optimizing the performance parameters of the movement mechanism of the electronic equipment by taking the minimum dynamic error as a target. Based on a multi-body dynamics method, the method respectively establishes the multi-rigid-body dynamic model and the rigid-flexible coupling multi-body model, optimizes to obtain the structural parameters of the high-precision and high-speed electronic equipment by taking the systemic dynamic accuracy as a target. The method has the advantages of accuracy, convenience, practicability and the like, contribution to improving the design capacity, acquisition of a better product structure and the like.

The invention provides a rocket-assisted unmanned aerial vehicle launching process multi-field coupling simulation analysis method. The method comprises the following steps: (1) dividing the rocket-boosted unmanned aerial vehicle launching process into five stages of fixing the unmanned aerial vehicle on the frame, sliding the unmanned aerial vehicle along the frame, completely separating the unmanned aerial vehicle from the launching frame until the booster finishes working, finishing the work of the booster until the booster is completely separated, and continuously flying the unmanned aerial vehicle; (2) establishing a six-degree-of-freedom kinetic equation set of the unmanned aerial vehicle, and on the basis, establishing a multi-rigid-body kinetic model of the unmanned aerial vehiclelaunching system in ADAMS software; (3) based on the aerodynamic blowing data, establishing an aerodynamic force calculation model capable of calculating aerodynamic force and an aerodynamic moment calculation model capable of calculating aerodynamic moment under different flight attitudes in real time; (4) establishing a flight control system model in the launching process of the unmanned aerialvehicle; and (5) building an unmanned aerial vehicle launching section multi-field coupling joint simulation data interaction platform.

The invention relates to an attitude angle rate measurement method based on a magnetic suspension control moment gyroscope. The attitude angle rate measurement method is capable of simultaneously carrying out spacecraft attitude control and spacecraft attitude angle rate measurement. The attitude angle rate measurement method based on the magnetic suspension control moment gyroscope comprises the following steps: building a magnetic suspension rotor dynamical model according to rigid body dynamics and the principle of coordinate transformation; indirectly obtaining an applied moment on a magnetic suspension rotor when a spacecraft and a framework rotate by using resultant moment born by the magnetic suspension rotor and a deflection moment of the magnetic suspension rotor when the spacecraft and the framework are static, wherein the resultant moment and the deflection moment are convenient to be directly measured and calculated; showing an analytical expression of the attitude angle rate of the spacecraft by using the magnetic suspension control moment gyroscope in a rectangular pyramid actuation mechanism according to an inertia moment theorem and an attitude measurement integration principle. The attitude angle rate measurement method based on the magnetic suspension control moment gyroscope is capable of replacing a rate gyroscope of a conventional attitude control system and reducing the volume and the weight of the attitude control system, belongs to the technical field of aerospace control and can be applied to high-accuracy spacecraft attitude control and measurement.

The invention discloses a stable walking control method and device for a biped robot, equipment and a readable medium. The stable walking control method comprises the steps: constructing a simplifiedrigid body dynamic model of a biped robot; constructing a centroid state prediction model by using the simplified rigid body dynamic model of the biped robot based on a model prediction control method; simplifying an optimization equation set in the model prediction control method into a quadratic programming equation set according to the centroid state prediction model; solving the quadratic programming equation set to obtain optimized ground reaction force so as to obtain stable walking control parameters; and controlling the biped robot according to the stable walking control parameters. According to the method, a problem is analyzed through the centroid control framework, and analysis of control over all parts of the body in the walking process of the robot is simplified; meanwhile, compared with a traditional feedback control method, the model prediction control method has high predictability, so that the robot has better robustness when walking on an unknown rugged road surface.

A distributed dynamics modeling method for a multi-leg robot comprises the following steps that (1) based on virtual model control, a trunk single rigid body serving as an object, simplifying legs into virtual actuator input, performing stress analysis, and establishing a single rigid body dynamics model; (2) adopting an iterative leg dynamics model resolving algorithm to establish a leg dynamicsmodel; the leg dynamic model resolving algorithm comprises the following steps: (1) taking a contact point between the tail end of a limb and the environment as a base coordinate system, and extrapolating to obtain an inertia force and a moment borne by the mass center of each rod piece; and (2) starting from the connection point of the trunk and the limbs, taking the force spinor of the limbs acting on the trunk as a controlled quantity, and performing inward pushing to obtain the interaction force spinor of the internal rod piece for realizing the controlled quantity and the contact force spinor of the limbs and the environment. According to the method, the complexity of model establishment is greatly reduced, the dynamics of the multi-leg robot is quickly updated, and the real-time requirement of control is met.

The invention provides a key parameter identification method for high-speed train dynamics performance design, which relates to the field of dynamics simulation design and analysis for the high-speed trains. A single-output LM neural network agent model is effectively used, and overall design of the high-speed train is merged in multi-subject global simulation design. The method comprises the following steps: a high-speed train multi-rigid-body dynamics physical model and a simulation model are firstly used, high-speed train dynamics performance input and output design space is determined, expert domain knowledge is used, and high-speed train dynamics performance design parameters and response indexes are extracted to shorten the design space; then, LM algorithm is adopted to adjust weights and thresholds of the neural network so as to improve the convergence speed and the convergence accuracy of the single-output neural network, and according to a sensitivity formula of input parameters in relative to an output value in the neural network, sensitivity is calculated; and finally, sensitivity analysis and key parameter identification are carried out on high-speed train design parameters. The method of the invention is mainly used for high-speed train dynamics analysis and design.

The invention discloses a machine tool moving part realizing method capable of meeting a high-acceleration requirement, which comprises: (1) determining working condition parameters of a moving part, such density, elastic modulus, fraction coefficient, basic overall dimension range and selected motor power; (2) taking the load inertia of the part as an optimal design target function, selecting a design variable, determining a constraint condition and establishing an optimal design mathematical model of the moving part; (3) solving an optimal problem by using a MATLAB algorithm, and determining the optimal overall dimension of the moving part; (4) establishing a three-dimensional model of the part; (5) based on virtual prototype technology, performing simulation analysis on the system through multi-steel body dynamic software, and detecting if the acceleration in motion of the part reaches requirement; (6) analyzing the high-acceleration start-up motion of the moving part by using finite element analysis software, and performing improved design of the weak positions of the moving part; and (7) determining the mechanical error of the part operating at high acceleration so as to perform real-time compensation in computer numerical control (CNC) programming. The method realizes the design of the moving part under a complex working condition by a simple method; and while ensuring product quality, the method greatly shortens product development period and reduces development cost.

The invention provides a solving method for composite limitations of operating space paths of an industrial robot.The method includes the steps that the operating space paths of the industrial robot are set; speed limitation conditions and acceleration limitation conditions of all axes are calculated, and limitation conditions of second derivatives of parameters are calculated according to the speed limitation conditions and acceleration limitation conditions of all the axes; torque limitation conditions of all the axes are calculated according to a rigid body dynamic model and the rotating part paths, and limitation conditions of first derivatives of the parameters are calculated according to the torque limitation conditions; speed limitation conditions and acceleration limitation conditions of operated workpieces are calculated according to the six-dimensional speed spinor of operating space of the industrial robot, and limitation conditions for the parameters are calculated according to the speed limitation conditions and the acceleration limitation conditions; composite limitation conditions for the industrial robot are unified on calculation on limitation conditions of the path parameters.Multiple limitation conditions of joint space and the operating space are effectively solved, and the composite limitations are uniformly shown.

The invention relates to a dynamic modeling and stability control method for a folding wing aircraft, which comprises the following steps: firstly, an aircraft with folding wings is taken as a multi-rigid-body system, and a multi-rigid-body dynamic model of the aircraft is established; secondly, the function relation between aerodynamic parameters and folding angles in the wing folding process iscalculated; thirdly, decoupling is conducted according to the decoupling conditions in combination with a kinematics equation, a dynamics equation and a navigation equation of the aircraft, a longitudinal motion equation of the aircraft is obtained, and dynamic characteristics of the aircraft are analyzed; finally, a nonlinear term, a coupling term and a parameter time-varying term existing in theaircraft longitudinal nonlinear kinetic model are regarded as total disturbance inside and outside the system, real-time estimation and compensation are conducted on the total disturbance, a PD controller is designed for the compensated system, and decoupling control over a speed channel and a height channel is achieved. According to the method, the modeling process is simplified, and derivationof rotational inertia is avoided; the controller is strong in anti-interference capability, high in control precision and suitable for deformation stability control of various variant aircrafts.

This invention discloses one human motion noise and error data catching correction method, which comprises the following steps: establishing human geometry mode; setting human quality distribution parameters; inputting human motion data; making parameters of human motion joint; establishing mixture Newton-Euler rigid dynamic force equation based on Euler angle and four element number; establishing physical binds optimization mode; setting optimization overlap times; using secondary program method to solve optimization mode to get human motion data.

The present invention provides a multi-wheel individual drive slip frequency steering vehicle united simulation method and system. The method comprises the steps of: creating a whole vehicle rigid multi-body dynamical model at first software, determining input information and output information of the whole vehicle rigid multi-body dynamical model, and outputting a whole vehicle model submodule, wherein the whole vehicle model submodule comprises the whole vehicle rigid multi-body dynamical model, the input information and the output information; creating a driver model at second software, wherein the driver model is configured to output driving data according to input expected data and feedback data; creating a whole vehicle controller at the second software, wherein the whole vehicle controller is configured to receive the driving data, and generate torque information; creating a steering simulation model at the second software, and leading the whole vehicle model submodule, the driver model and the whole vehicle controller into the steering simulation model; and designing a working condition in the steering simulation model to perform simulation analysis of the work condition and obtain a simulation result. The multi-wheel individual drive slip frequency steering vehicle united simulation method and system can perform closed-loop simulation analysis of different work conditions and can improve the accuracy.

The invention discloses an aerodynamic /control integrated coupling simulating technology in the aircraft maneuvering process, and relates to the field of computational fluid mechanics and the field of control systems. The main work implementing process includes the steps of generating a control signal through the compared deviation of the attitude angle of an aircraft and a control target, outputting the control signal to a PID controller module, generating a rudder deviation angle signal after computation, outputting the rudder deviation angle signal to a dynamic mesh module, deflecting a rudder face to a corresponding angle through a dynamic mesh technology, obtaining a dynamic flow field existing after deflection of the rudder face through a Navier-Stockes equation module, generating aerodynamic force and torque signals, outputting aerodynamic force and torque to a rigid body dynamics equation and a kinematical equation, obtaining the flight attitude of the next moment, transmitting the new flight attitude to the PID controller module, and forming a closed-loop numerical simulating circuit. The high-precision simulation of a flight control system is achieved, and the technology can be used for evaluating performance of the flight control system and studying the influences of the aerodynamic force unsteady effect on the control system.

The invention discloses a method for analyzing and solving an expected attitude of near-earth orbit spacecraft sunlight in reflection staring. The method comprises the following steps of establishinga target coordinate system according to orbit information of a spacecraft and target longitude and latitude information; establishing components of three axes of the target coordinate system under aninertial coordinate system so as to establish an expected quaternion of the target coordinate system relative to the inertial coordinate system; and further combining a rigid body dynamics basic theory, and finally determining an angular speed and an angular acceleration of the target coordinate system by solving a primary derivative and a secondary derivative so as to determine an integral analysis form of target attitude information. According to the invention, when the spacecraft executes a sunlight reflection staring task, the target angular speed and the angular acceleration do not need to be solved by methods such as difference, and the defects of large error and the like generated by the traditional difference method are overcome; and when the target attitude is solved, shape factors such as the oblateness of the earth and the like are considered, and the method is not based on the spherical assumption of the earth any more and is more in line with the engineering practice.

The invention provides a spinning speed control method for a space flexible electric sail, belongs to a field of electric sails and specifically relates to the spinning speed control method for the space flexible electric sail. The method includes steps of 1, establishing a large deformation dynamics model of a flexible rope based on an absolute node coordinate method, determining unit nodes, deducing a constant quality matrix and generalized elastic force in a reference configuration; 2, establishing a central rigid body dynamics model, establishing a 1-DOF (Degree Of Freedom) constraint algebraic equation for a central rotation constraint pair, establishing a 3-DOF constraint algebraic equation for a connection spherical hinge of the flexible rope and the central rigid body; 3, performing stress analysis on the flexible rope and calculating the flexible rope rotation angle acceleration in a dynamic balance state; 4, selecting a control variant and designing speed control rate according to stress analysis and obtaining a speed control torque needed to output by the central rigid body through calculation. The invention solves a problem that speed control of a flexible rope spinningmulti-body system of the flexible sail cannot be realized and can be applied to an electric sail control system.

The invention provides a machine tool design method, comprising the steps of a) creating a machine tool physical model according to parts processing technology and assembling technology, b) exerting a driving signal to the physical model and measuring the platform dynamic precision, c) transferring the physical model into a mathematical model and solving, d) analyzing the parameters and optimizing the machine tool design. The machine tool design method of the invention directly uses the dynamic property of machine tool as the evaluating object, rigid body dynamics calculation as the manner of analyzing and combined property parameter of motor function element as analyzing and optimizing object, having the advantages of clear target, reasonable method, convenient analysis, etc.

The invention relates to a double-shaft balancing design method of a V8 type diesel engine. The double-shaft balancing design method comprises theoretical design, multi-rigid-body dynamics simulation and rigid-flexible coupling vibration simulation; the theoretical design comprises the steps of selection of air cylinder included angles and crank modes, fitting of an upsetting moment and analysis of harmonic waves and determination of balancing shaft spatial layout modes, phase angles, mass distribution, cross section shapes and parameters; a V8 type diesel engine multi-rigid-body model is built by dynamics simulation, and a double-shaft balancing effect determined by the theoretical design is verified; rigid-flexible coupling vibration simulation aims at the V8 diesel engine which is additionally provided with the double-shaft balancing design to build a diesel engine rigid-flexible coupling model, and stimulation is conducted on the vibration condition of the diesel engine which is additionally provided with a balancing device, and the balancing effect of a double-shaft balancing scheme is verified on the other hand. The double-shaft balancing design method of the V8 type diesel engine has the advantages that the method which combines the theoretical design with the dynamics simulation together is adopted, results in the stages are verified mutually, the correctness of the design scheme is ensured, and the reasonability of the design scheme and the good balancing effect can further be ensured.