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This paper presents algorithms for computing the angular velocities of the bodies of a multibody system. A multibody system is any collection of connected bodies. The focus is upon multibody systems consisting of spherically pinned rigid bodies which do not form closed loops. Simple formulae are presented for computing the angular velocities. It is shown that once the angular velocities are known the entire kinematical description and hence, the dynamics of the system, may be developed routinely and in automated fashion. Extension to more general multibody systems follows without conceptual change in the procedures.

This paper discusses algorithms for large displacement analysis of interconnected flexible and rigid multibody systems. Hydrostatic and hydrodynamic loads for systems being submerged in water are also considered. The systems may consist of cables and beams and may combine very flexible parts with rigid parts. Various ways of introducing structural joints are discussed. A special implementation of the Hilber‐Hughes‐Taylor time integration scheme for constrained non‐linear systems is outlined. The formulation is general and allows for displacements and rotational motion of unlimited size. Aspects concerning efficient solution of constrained dynamic problems are discussed. These capabilities have been implemented in a general purpose non‐linear finite element program. Applications involving static and dynamic analysis of a bi‐articulated tower and a floating tripod platform kept in place by three anchor lines are discussed.

Wind turbines are of growing importance for the production of renewable energy. The kinetic energy of the blowing air induces a rotary motion and is thus converted into electricity. From the mechanical point of view the complex dynamics of wind turbines become a matter of interest for structural optimization and optimal control in order to improve stability and energy efficiency. The purpose of this paper therefore is to present a mechanical model of a three‐blade wind turbine with a momentum and energy conserving time integration of the system.

The authors present a mechanical model based upon a rotationless formulation of rigid body dynamics coupled with flexible components. The resulting set of differential‐algebraic equations will be solved by using energy‐consistent time‐stepping schemes. Rigid and orthotropic‐elastic body models of a wind turbine show the robustness and accuracy of these schemes for the relevant problem.

Numerical studies prove that physically consistent time‐stepping schemes provide reliable results, especially for hybrid wind turbine models.

The application of energy‐consistent methods for time discretization is intended to provide computational robustness and to reduce the computational costs of the dynamical wind turbine systems. The model is aimed to give a first access into the investigation of fluid‐structure interaction for wind turbines.

A number of computer codes are available for the automatic generation of the equations of motion of multibody systems formed by rigid bodies. Systems containing deformable components generally cannot be treated readily by these programs. Demonstrates how multibody systems containing both rigid and deformable components can be handled with the aid of Autolev, a symbol manipulator for dynamics, when such components are discretized by a Rayleigh‐Ritz procedure. A computer code called Ritz was written to perform this task interactively with Autolev, and a Fortran program is generated automatically for the numerical simulation of motions of the system under consideration. The numerical results are then converted to Matlab format, so that plotting routines and other facilities available in Matlab can be used to process the results further.

Bulk material-handling equipment development can be accelerated and is less expensive when testing of virtual prototypes can be adopted. However, often the complexity of the interaction between particulate material and handling equipment cannot be handled by a single computational solver. This paper aims to establish a framework for the development, verification and application of a co-simulation of discrete element method (DEM) and multibody dynamics (MBD).

The two methods have been coupled in two directions, which consists of coupling the load data on the geometry from DEM to MBD and the position data from MBD to DEM. The coupling has been validated thoroughly in several scenarios, and the stability and robustness have been investigated.

All tests clearly demonstrated that the co-simulation is successful in predicting particle–equipment interaction. Examples are provided describing the effects of a coupling that is too tight, as well as a coupling that is too loose. A guideline has been developed for achieving stable and efficient co-simulations.

This framework shows how to achieve realistic co-simulations of particulate material and equipment interaction of a dynamic nature.

The existence of clearance in joints of positioning mechanism is inevitable and the movements of the real mechanism are deflected from the ideal mechanism due to the clearances. The purpose of this paper is to investigate the effects of clearance on the dynamic characteristics of dual-axis positioning mechanism of a satellite antenna.

The dynamics analysis of dual-axis positioning mechanism with clearance are investigated using a computational approach based on virtual prototyping technology. The contact model in joint clearance is established by using a hybrid nonlinear continuous contact force model and the friction effect is considered by using a modified Coulomb friction model. Then the numerical simulation of dual-axis positioning mechanism with joint clearance is carried out and four case studies are implemented for different clearance sizes.

Clearance leads to degradation of the dynamic performance of the system. The existence of clearance causes impact dynamic loads, and influences the motion accuracy and stability of the dual-axis positioning mechanism. Larger clearance induces higher frequency shakes and larger shake amplitudes, which will deteriorate positioning accuracy.

Providing an effective and practical method to analyze dynamic characteristics of dual-axis positioning mechanism of satellite antenna with joint clearance and describing the dynamic characteristics of the dual-axis positioning system more realistically, which improves the engineering application.

The paper is the basis of mechanism design, precision analysis and robust control system design of dual-axis positioning mechanism of satellite antenna.

The purpose of this paper is to introduce a co‐simulation method to study the ground maneuvers of aircraft anti‐skid braking and steering.

A virtual prototype of aircraft is established in the multibody system dynamics software MSC.ADAMS/Aircraft. The anti‐skid braking control model, which adopts the multi‐threshold PID control method with a slip‐velocity‐controlled, pressure‐bias‐modulated (PBM) system, is established in MATLAB/Simulink. EASY5 is used to establish the hydraulic system of nose wheel steering. The ADAMS model is connected to block diagrams of the anti‐skid braking control model in MATLAB/Simulink, and is also connected to the block diagrams of nose wheel steering system model in EASY5, so that the ground maneuvers of aircraft anti‐skid braking and steering are simulated separately.

Results are presented to investigate the performance of anti‐skid braking system in aircraft anti‐skid simulation. In aircraft steering simulation, the influence of two important parameters on the forces acting on the tires is discussed in detail, and the safe area to prevent aircraft sideslip is obtained.

This paper presents an advanced method to study the ground maneuvers of aircraft anti‐skid braking and steering, and establishes an integrated aircraft model of airframe, landing gear, steering system, and anti‐skid braking system to investigate the interaction of each subsystem via simulation.

The purpose of this study is to investigate the deployment and control of cable-driven flexible solar arrays.

First, dynamic model of the system is established by using the Jourdain’s velocity variation principle and the single direction recursive construction method, including the dynamic equation of a single flexible body, the kinematical recursive relation of two adjacent flexible bodies and the dynamic equation of the solar array system. Then, the contribution of joint friction to the dynamic equation of the system is derived based on the virtual power principle. A three-dimensional revolute joint model is introduced and discussed in detail. Finally, a proportion-differentiation (PD) controller is designed to control the drift of the system caused by the deployment.

Simulation results show that the proposed model is effective to describe the deployment of flexible solar arrays, joint friction may affect the dynamic behavior of the system and the PD controller can effectively eliminate the spacecraft drift.

This model is useful to indicate the dynamics behavior of the solar array system with friction.

The relationship between ideal constraint force and Lagrange multipliers is derived. The contribution of joint friction to the dynamic equation of the system is derived based on the virtual power principle. A PD controller is designed to control the drift of the system caused by the deployment of solar arrays.

While the normal wheel–rail contact model cannot be accurately used for light rail transit (LRT) wheel wear analysis with large wheelset lateral displacement and wheelset yaw angle, a modified semi-Hertzian contact model (MSHM) is proposed in the paper.

MSHM was first proposed to consider the wheelset motion with the lateral displacement and the yaw angle. Then, a dynamic model of an LRT was established and the influence of some key factors on wheel wear is analyzed. At last, after operating for a certain mileage, the predicted wheel wear is compared with the tested wheel wear.

Compared with the tested wheel wear, the predicted wheel wear shows a good agreement with the measured result, verifying the accuracy of MSHM.

Considering larger wheelset lateral displacement and yaw angle, MSHM can be used to calculate the wheel wear of the LRT with high accuracy.

A software package is developed for the modelling and animation of viscous incompressible fluids. The full time‐dependent Navier‐Stokes equations are used to simulate 2D and 3D incompressible fluid phenomena which include shallow and deep fluid flow, transient dynamic flow, vorticity and splashing in simulated physical environments. The package also allows the inclusion of variously shaped and spaced static or moving obstacles that are fully submerged or penetrate the fluid surface. Stable numerical analysis techniques based on finite‐differences are used for the solution of the Navier‐Stokes equations. To model free‐surface fluids, a technique based on the Marker‐and‐Cell method is presented. Based on the fluid’s pressure and velocities obtained from the solution of the Navier‐Stokes equations this technique allows modelling of the fluid’s free surface either by solving a surface equation of by tracking the motion of marker particles. The latter technique is suitable for visualization of splashing and vorticity. Furthermore, an editing tool is developed for easy definition of a physical‐world which includes obstacles, boundaries and fluid properties such as viscosity, initial velocity and pressure. Using the editor, complex fluid simulations can be performed without prior knowledge of the underlying fluid dynamics equations. Finally, depending on the application fluid rendering techniques are developed using standard Silicon Graphics workstation hardware routines.