bluuebunny/crossref_metadata_2025_split huggingface dataset:
Direct Yaw Moment Control for Motorized Wheel Electric Vehicles
Authors: Goodarzi Avesta , Esmailzadeh Ebrahim , Vossoughi G. R. 
Published: November 2020

Abstract
A new control law for direct yaw moment control of an electric vehicle is developed. Although this study is considered as part of a global control system for the traction control of a four motorized wheel electric vehicle, but the results of this study is quite general and can be applied to other types of vehicles. The dynamic model of the system has been analyzed and, in accordance with the optimal control theory, an optimal controller is designed. Two different versions of the control law have been considered and the performance of each version has been separately studied and compared with each other. Finally, the numerical simulation of the vehicle-handling model with and without the use of the optimal yaw moment controller has been carried out. Results obtained indicate that considerable improvement in the vehicle handling has been achieved when the optimal yaw moment controller is engaged.
The Idea of Complementarity in Multibody Dynamics
Authors: Pfeiffer Friedrich 
Published: November 2020

Abstract
Considered in a straightforward manner multibody systems with many multiple unilateral contacts involve a combinatorial problem of huge dimensions, which can only be solved reasonably by the introduction of the complementarity idea. It states that for unilateral contacts either relative kinematics is zero and the corresponding constraint forces are not zero, or vice versa. This leads to a complementarity problem which is somehow related to linear programming problems. Paper discusses the theoretical and practical background.
Lumped-Parameters Brick Element for Modeling Shell Flexible Multibody Systems
Authors: Wasfy Tamer M. 
Published: November 2020

Abstract
An eight-node lumped-parameter brick element, suitable for modeling flexible multibody shell components, is described. The element is composed of twelve truss sub-elements for modeling the membrane and bending modes and six surface shear elements for modeling the shear and warping modes. The element is strategically designed to eliminate locking and spurious modes. Cartesian nodal coordinates are used as degrees-of-freedom with no rotational degrees-of-freedom. This simplifies the coordinate transformations and inertia calculations. A total Lagrangian displacement formulation where the element deformations are measured relative to the unstressed element is employed. The equations of motion are integrated using an explicit temporal integration algorithm. Standard finite element and flexible multibody dynamics test problems are solved to demonstrate the accuracy and robustness of the element. Also, the use of the element in a practical flexible multibody dynamics application, namely, deployment of a large space structure, is demonstrated.
Design of Vibration Absorbers for Step Motions and Step Disturbances
Authors: Fortgang Joel , Singhose William 
Published: November 2020

Abstract
Mechanical systems with flexible dynamics often suffer from vibration induced by changes in the reference command or from external disturbances. The technique of adding a secondary oscillatory system, called a vibration absorber, has proven useful at eliminating vibrations from external disturbances and rotational imbalances. Traditionally, vibration absorbers have been designed for systems subject to sinusoidal or random excitations. Here the applicability of vibration absorbers to systems with step changes in the reference command or similar disturbances is studied. The absorber can be designed with a weighting on peak overshoot and settling time, with the possibility of a nearly 90% improvement in settling time. The performance of this new absorber is compared with previously proposed vibration absorbers.
Cylindrical Workpiece Turning Using Multiple-Cutter Tool Heads
Authors: Gouskov Alexander M. , Paris Henri , Voronov Sergey A. , Batzer Stephen A. 
Published: November 2020

Abstract
The dynamics of turning by a tool head with two multiple-cutter rows is considered. The mathematical model of the process with two commensurate delays with possible cutting discontinuity is analyzed. The domains of dynamic instability are derived, and the influence of technological parameters on the system response is presented. The numeric analysis of system dynamics on discontinuity of cutting is given. In particular, it is shown that there exists specific conditions for given regimes, in which one row of cutters produces an intermittent chip form while the other row produces continuous chips. It is shown that the contribution of parametric excitation by shape roughness of an imperfect (unmachined) cylindrical workpiece surface is not substantial due to the special filtering properties of multiple cutters uniformly circumferentially distributed along the tool head.
On the Transversal Vibrations of a Conveyor Belt Using a String-Like Equation
Authors: Suweken Gede , van Horssen W. T. 
Published: November 2020

Abstract
In this paper an initial-boundary value problem for a linear wave (string) equation is considered. This problem can be used as a simple model to describe the vertical vibrations of a conveyor belt, for which the velocity is small with respect to the wave speed. In this paper the belt is assumed to move with varying speed. Formal asymptotic approximations of the solutions are constructed to show the complicated dynamical behavior of the conveyor belt. It also will be shown that for this problem, the truncation method is not valid on long time scales.
Dynamic Stability of Rotating Abrasive Tool for Deep Hole Honing
Authors: Gouskov Alexander M. , Voronov Sergey A. , Batzer Stephen A. 
Published: November 2020

Abstract
The results of a dynamic stability analysis of a deep hole honing tool are presented. The mathematical model of abrasive machining is analyzed under different support conditions and tool locations on a flexible central shaft. The non-conservative interaction loads of cutting are derived. Complex eigenvalues of system vibrations are calculated. Finally, the influences of system parameters on the stability conditions of dynamic behavior are analyzed.
Combined Parametrical and Transversal Excitation of a Stretched String in an Elastic Medium
Authors: Caswita  , van der Burgh A. H. P. 
Published: November 2020

Abstract
In this paper we consider a two-point boundary alue problem for an integrodifferential equation. This equation can be considered as a nonlinearly perturbed telegraph equation including both parametrical and transversal excitation. The attention will be focused on time-periodic solutions consisting of two modes. The first mode is generated by parametrical excitation and the second one is generated by vertical (transversal) excitation. This interaction of two modes can occur for special combinations of values of two parameters in the equation For the study of time-periodic solutions the averaging method will be used and the stability of the time-periodic solutions will be analyzed in linear approximation.
Forced Response of a SDOF Friction Oscillator Colliding With a Hysteretic Obstacle
Authors: Andreaus Ugo , Casini Paolo 
Published: November 2020

Abstract
The forced dynamics of non-smooth oscillators have not yet been sufficiently investigated, when damping is simultaneously due to friction and impact. Because of the theoretical and practical interest of this type of systems, an effort is made in this paper to lighten the behaviour of a single-degree-of-freedom oscillator colliding with a hysteretic obstacle and excited by an harmonic driving force and by a moving base with constant velocity.
A friction-contact model has been proposed which allows simulating an exponential velocity-dependent friction law, and a deformable (hysteretic) obstacle. This model has been numerically tested via a sample application.
Differential Isolation of Science Instrumentation Packages
Authors: Bower Bruce , Knowles Gareth 
Published: November 2020

Abstract
Vibratory load transmission reduction for precision space optics is demonstrated through a new concept of electronic differential controlled isolation. Lightweight, compact and with very low power consumption, differential controlled isolation can meet the active/passive isolation performance needs in large precision optics, launch system, science instrument modules and observation systems. This includes large optic, interferometric and formation flying platforms. Inexpensive to manufacture, the technology provides flexibility in design to meet many challenges. Although the main thrust of this research was to address OTA truss/ISIM isolation needs, the developed technology is directly applicable to many mission critical needs in launch and deployment of precision space systems.
A Unified Methodology for Modeling Hysteresis in Ferroic Materials
Authors: Smith Ralph C. , Massad Jordan E. 
Published: November 2020

Abstract
This investigation focuses on the development of unified techniques for mathematically modeling the hysteresis and constitutive nonlinearities inherent to ferroelectric, ferromagnetic and ferroelastic materials at moderate to high drive levels. Motivating materials include piezoceramics, relaxor ferroelectrics, magnetostrictives and shape memory alloys, but the modeling approach is sufficiently general to include a large variety of ferroic compounds. The nonlinear and hysteretic behavior of these materials can be attributed to their underlying domain structure and this common ferroic framework is utilized to construct unified constitutive models for the materials. These models are constructed in two steps. In the first, thermodynamic principles are employed to quantify the anhysteretic behavior which would result in the absence of inclusions in the material. In the second step, energy relations are employed to quantify the irreversible and reversible motion of domains walls about pinning sites in the material. The resulting models are formulated as low-order ordinary differential equations. The performance and behavior of the models are illustrated for piezoceramic, magnetostrictive and shape memory compounds.
Parameter Identification for Preisach Models of Hysteresis
Authors: Galinaitis William S. , Joseph Daniel S. , Rogers Robert C. 
Published: November 2020

Abstract
In this paper we consider the abstract mathematical problem of identifying a Preisach operator from idealized training data. We give sufficient conditions on the training data to identify an optimal approximation to the operator. We also show that it is possible to introduce errors if one tries to approximate the operator in the “wrong” function space. We demonstrate the utility of these results using experimental data from SMA wires. We identify the optimal operator using this data and evaluate the performance of the operator in temperature controlled experiments.
Modeling Hysteretic Stress-Strain Relationships With Graphical User Interface
Authors: Zhang Yue 
Published: November 2020

Abstract
The stress-strain relationship of rubber materials manifests as hysteresis loops under finite strain. In this paper, some results from applying an integral formulation that encompasses a memory kernel of time and a nonlinear function of the strain to model extensions of rubber rods are presented. Various experimental data loops are studied. In addition, the author presents a graphical user interface that facilitates the modeling process.
Motion and Vibration Control of Three Dimensional Flexible Shaking Table Using LQI Control Approach
Authors: Hiramatsu Hidefumi , Fuji Daijiro , Seto Kazuto , Watanabe Toru 
Published: November 2020

Abstract
This paper deals with a design procedure of control system for a three-dimensional flexible shaking table.
The shaking table should be less weighted so that actuators require less control forces and higher fidelity to control commands. However, as the weight of shaking table is reduced, the natural frequencies of vibration modes of the table appear on operating frequency region. Such vibration modes get into problem that may cause spillover instability. So, the research purpose is to control such vibration and motion by using the modeling method presented by Seto [1].
Utilizing the model, state equation system model including integrator is composed and feedback controller is designed by using LQI control law. As the system model both includes the multi-degree-of -freedom-structure model and integrator, the designed controller achieves simultaneous motion and vibration control.
Computer simulation and control experiments are carried out and the effectiveness of the presented procedure is investigated.
Actuator Placement for Active Vibration Control Systems With External Excitations
Authors: Yuan Shuqing , Xie Lihua 
Published: November 2020

Abstract
Actuator placement is important to active vibration suppression. It is complex as it concerns many effects. In this paper, a new actuator position optimization criterion is proposed in which the effect of external excitations is considered. The criterion is applied in conjunction with the Independent Modal Space Control method. Effects of different modes are weighted to form a cost function according to their contributions to system dynamic responses, which directly reflect the effects of the external excitations. An example is given to validate the criterion.
High Durability of Functionally Graded Piezoelectric Bending Actuators
Authors: Qiu Jinhao , Tani Junji , Morita Teppei , Takahashi Hirofumi 
Published: November 2020

Abstract
A new type of functionally graded (FG) piezoelectric bending actuator was proposed by the authors in the former study and the advantage of the new actuator over the traditional bimorph and unimorph actuators in internal stress distribution was illustrated by simulation results. In this study, functionally graded piezoelectric bending actuator was designed and fabricated. The material compositions with different dielectric and piezoelectric constants were selected from the Pb(Ni1/3Nb2/3)O3-PbZrO3-PbTiO3 (PNN-PZ-PT) family and used as the four layers in the new FG piezoelectric actuator. The piezoelectric constant and dielectric constant were graded oppositely in the thickness direction. Stress distribution of the FG piezoelectric actuator under external voltage was analyzed using finite element method (FEM) and the simulation results showed the stress discontinuity of the new actuator is smaller than that of traditional bimorph actuator. Durability of the fabricated FG piezoelectric actuators was measured in a vibration test and compared with that of the traditional bimorph actuator to evaluate the improvement of performance. The results showed that the durability of the FG piezoelectric actuators is much higher than that of the bimorph actuator.
Friction Induced Brake Vibrations
Authors: Rudolph Martin , Popp Karl 
Published: November 2020

Abstract
This paper deals with friction induced brake vibrations showing frequencies above 1 kHz and a narrow bandwidth. This phenomenon is usually called ‘brake squeal’.
After analyzing squeal excitation mechanisms, a rigid body brake model displaying the main features of a floating caliper disc brake is presented.
A brake noise test rig has been installed and is used to verify simulations which are based on the 14 DOF multibody model.
A stability analysis as well as a sensitivity analysis have been conducted in order to find recommendations for a brake design avoiding squeal. From the outcomes of these calculations design modifications have been derived which were tested by TRW Automotive Company. The dependence of squeal occurrence on brake pressure has been predicted by the developed theoretical model.
Spatial Contact Mechanics of CVT Chain Drives
Authors: Sedlmayr Martin , Pfeiffer Friedrich 
Published: November 2020

Abstract
A method for the simulation of spatial dynamics of CVT chain drives is proposed in this paper. Dealing with an elastic multibody system, special care has been taken to describe the contact mechanics of interconnected rigid and/or elastic bodies. Simulation results show the influence of the geometry and the kinematics on the vibrational behavior of the transmission. Furthermore effects on the efficiency and working forces are discussed.
Development and Experimental Validation of a Point Contact Model for Dynamical Problems With Friction
Authors: Sextro Walter 
Published: November 2020

Abstract
The contact forces are dependent on many parameters, such as contact stiffnesses, surface profiles, material parameters, temperature distribution, relative motion and normal pressure distribution. These parameters can change within the contact area and from here, it is impossible to derive a general force law. The only possibility to overcome this problem is to discretize the contact areas, since in general the relative motion and the contact parameters are not constantly distributed within the contact surface. This leads to a point contact model, which has to include all main physical effects as described above, which are important, when simulating dynamical contact problems with friction.
The friction model includes the main parameters such as the roughness of the contact surfaces, the nonlinear friction law, the contact stiffnesses in normal and tangential direction. The decreasing characteristic of the friction coefficient with respect to the relative velocity has to be modeled in a sufficient way. With respect to the dissipation of energy, the hysteretic behavior is studied with respect to the normal and tangential direction. Separation of the contact is included.
This point contact model is be applied to real dynamical contact problems. In the first example, a simple impact oscillator with an elastic contact is used to check the overall modeling with respect to the elastic normal contact. Then, a self excited friction oscillator is investigated with respect to the tangential contact. Here, the modeling of surface waviness leads to high periodic solutions, which is also observed within the experiments. In both examples, the comparison of measurements and calculated phase plots is good.
Furthermore, the influence of wear on to the surface profile, contact area and normal pressure distribution is investigated. From here, it follows, that friction leads to time dependent systems.
On Equivalence of the Moving Mass and Moving Oscillator Problems
Authors: Pesterev Alexander V. , Bergman Lawrence A. , Tan Chin An , Tsao T.-C. , Yang Bingen 
Published: November 2020

Abstract
Asymptotic behavior of the solution of the moving oscillator problem is examined for large values of the spring stiffness for the general case of nonzero beam initial conditions. In the limit of infinite spring stiffness, the moving oscillator problem for a simply supported beam is shown to be not equivalent in a strict sense to the moving mass problem; i.e., beam displacements obtained by solving the two problems are the same, but the higher-order derivatives of the two solutions are different. In the general case, the force acting on the beam from the oscillator is shown to contain a high-frequency component, which does not vanish, or even grows, when the spring coefficient tends to infinity. The magnitude of this force and its dependence on the oscillator parameters can be estimated by considering the asymptotics of the solution for the initial stage of the oscillator motion. For the case of a simply supported beam, the magnitude of the high-frequency force linearly depends on the oscillator eigenfrequency and velocity. The deficiency of the moving mass model is noted in that it fails to predict stresses in the bridge structure. Results of numerical experiments are presented.
Effects of Boundary Flexibility in the Moving Oscillator Problem
Authors: Tan Chin An , Chen Yonghong , Bergman Lawrence A. 
Published: November 2020

Abstract
In this paper, the problem of an oscillator moving across an elastically supported Euler-Bernoulli beam is examined. The oscillator is modeled by a one-degree-of-freedom sprung mass and the end supports are modeled by linear springs in the transverse direction. Solution for the response of the beam is represented by an eigenfunction expansion series. Numerical results are obtained for the eigenvalues and the response of the elastically supported beam, and the interaction force (force in the oscillator spring). To guide the discussion, a critical value of the support stiffness is determined from the plot of the first natural frequency versus the support stiffness. Effects of the boundary flexibility on the maximum beam response and the maximum interaction force are discussed as a function of the speed and the oscillator frequency. The boundary flexibility is shown to have a significant implication in the design analysis of the moving oscillator problem, especially for shorter span beam structures.
Aquatic Mobile Robot Using Waving Motion of a Flexible Fin
Authors: Muramatsu Koichi , Watanabe Masahiro , Kobayashi Nobuyuki 
Published: November 2020

Abstract
This paper deals with an experimental study of propulsive performance of aquatic mobile robot using waving motion of a flexible plate modeled on the flexible caudal fin of fish. The flexible plate is attached at the trailing edge of the oscillating robot body in the shape of wing pitching and heaving around the leading edge of the body, and the waving motion of the flexible plate is excited by motion of the oscillating body. In the experiment, first, the propulsion force and the side force generated by the waving motion of the flexible plate are measured for various length, exciting frequency and flexibility of the flexible plate in stationary water in a channel. Secondly, the swimming speed and propulsive efficiency are examined. As a result, it is found that the propulsive performance of the robot using flexible plate is higher than that of the rigid plate. And the high propulsive performance of propulsive efficiency of 62% and mean swimming speed of 0.3m/s are obtained by using the waving motion of the flexible plate.
Sensorless Modal Stabilization for Three-Link Robotic Arm With Elastic Wrist Drive Belt
Authors: Hosek Martin 
Published: November 2020

Abstract
A control system for a three-link direct-drive robotic manipulator with inherent structural flexibilities is presented. The structural flexibilities introduce undesirable vibration modes which may affect operation of the robot motion controller, resulting in destabilization of the closed-loop system. This represents a major limiting factor for implementation of a conventional controller designed solely for the rigid body dynamics of the robotic manipulator. The fundamental idea in the presented approach is to use a composite controller which consists of a trajectory-tracking section designed for the rigid-body dynamics and a vibration-damping compensator added for attenuation of the dominant flexible dynamics. The vibration damping compensator operates on estimated states of the dominant flexible dynamics obtained from a reduced-order state observer. A mechanism is implemented which allows the robotic manipulator to move through or hold in positions where the dominant flexible dynamics is unobservable and uncontrollable. Results of laboratory tests document that the presented approach leads to improved stability and control performance.