bluuebunny/crossref_metadata_2025_split huggingface dataset:
Quantitative Identification of Vehicle Rattle Sources Using CAE and Experimental Tools
Authors: Her Jen Yaun , Hsieh Shang-Rou , Moore James A. 
Published: February 2021

Abstract
Vehicle rattle noise, generated when parts impact each other due to road, wind or powertrain induced vibration excitation, has become one of the major customer concerns in recent years. Traditional find and fix methods for rattle problems rely on a subjective assessment in identifying and locating the rattle before corrective action is taken. This paper presents a simple technique to quantitatively determine the location and strength of rattle using a microphone and an accelerometer. A CAE tools had also been introduced to identify potential rattle hot spots early in the design process before prototype vehicle have been built. The correlation between the experimental technique and CAE prediction for identifying rattle sources in a prototype vehicle is also presented.
Self-Compensating Control for Suppression of Rotational Speed Variation Excited by Reduction Gear Mechanism
Authors: Itoh Masahiko , Kasei Shinji , Fukada Shigeo 
Published: February 2021

Abstract
In servo-controlled mechanical systems, such as industrial machines and robots, several kinds of gear reducers are proposed and employed selectively. It is known that these gear reducers generate speed and torque variations due to their element error, alignment error, etc., which result in excitations of undesirable vibrations in driven machines. This paper presents a control technique for suppressing such vibration source in the gear reducers themselves, especially relating to excitations in a lower-frequency range. This technique is based on a self-compensating control applied to the gear reducer. This control loop has band-pass filters whose center frequencies track changes in the motor speed and gain adjusters. A gear reducer referred as harmonic drive type being taken up, theoretical approaches are performed on the stability and other performances of the control systems. Simulations and experiments show satisfactory control results in constant speed, acceleration and deceleration states of the motor.
Sliding Mode Control With Pre-Filter for Spillover and Chattering Suppression
Authors: Ito Takayuki , Nonami Kenzo 
Published: February 2021

Abstract
We discuss the sliding mode control to suppress a spillover phenomena caused by truncation of the higher flexible modes for a flexible system. We propose a new method to suppress a higher frequency region including a truncated flexible modes and chattering by filtering control inputs through low-pass filter. And also, we can easily design a control system and apply for an actual system. We have verified from simulations and experiments for flexible structure that the proposed method has good performance and is very useful for spillover suppression.
Fuzzy Changing Stiffness Control of the Unstable Vibration of a Centrifuge Rotor
Authors: Yuan Y. , Liu S. Y. , Wen B. C. 
Published: February 2021

Abstract
Fuzzy control theory is used to control the unstable vibration of a centrifuge rotor by means of changing support stiffness. The solid–liquid coupling equations of a centrifuge rotor are presented. A fuzzy changing stiffness controller with changeable control rules is designed. Parameters of the controller are optimized by an optimization method. This control method is realized on a horizontal centrifuge rotor. Experimental results show that fuzzy changing stiffness control (FCSC) can stabilize the unstable vibration of a centrifuge rotor effectively.
Development of an Active Mass Damper for Stabilizing the Load Suspended on a Floating Crane
Authors: Iwasaki Itaru , Tanida Koji , Kaji Sokichi , Mutaguchi Masao 
Published: February 2021

Abstract
To minimize the necessity to suspend shackling work floating crane on account of vessel rolling, an active mass damper system was developed to attenuate oscillation of the sling frame under which the shackles are suspended. The motion of actual floating crane under sea wave was measured to determine the mechanism of sling frame oscillation, and to verify from theoretical analysis the effectiveness of installing an active mass damper on the sling frame. For further ascertaining damper performance, a 1/40 size model of the crane barge mounted with the damper was tested in tank, which indicated reduction to 1/3 – 1/2 of sling frame oscillation, with good agreement between the theoretically estimated and measured results. Test at sea on actual floating crane equipped with active mass damper system confirmed that actuation of the system would reduce to roughly 1/2 the oscillation of sling frame.
Control Performance of Hadamard-Weighted H2 Controller for Multiple-Input Structure System
Authors: Watanabe Toru 
Published: February 2021

Abstract
In this study, a design method of a controller taking account of integrity is presented using Hadamard weighted H2 control theory. Numerical calculations are carried out by using a structure model with an active dynamic vibration absorber (ADVA) and an active vibration isolator (AISO). It is shown that the controller designed by using the proposed method realizes higher integrity than the ordinary weighted H2 controller, though it requires more amount of control inputs to achieve same vibration reduction effect in average.
Order Reduction of Controller Based on LMIs Improving Error Bounds
Authors: Saragih Roberd , Kazuo Yoshida 
Published: February 2021

Abstract
In this paper, we propose an order reduction method of controller based on combination of the alternating projection method and the balanced truncation. In this method both the errors of controller and the closed-loop system caused by the reduced-order controller can be improved simultaneously. By using a generalized Bounded Real Lemma, a feasible reduced-order controller can be derived. The sufficient condition for the existence of a reduced-order controller leads to a non-convex feasibility problem. To solve the problem, we can use an improved computational scheme based on the alternating projection method. But it is needed so much time to solve the problem if compared by the other methods. To validate the proposed method, some numerical calculations and simulations are carried out.
Development and Testing of Variable Gain Control Algorithms for Seismic Response Control of a Full-Scale Structure
Authors: Iemura Hirokazu , Igarashi Akira , Inoue Yutaka , Sakamoto Mitsuo 
Published: February 2021

Abstract
In order to use Active Mass Dampers (AMD) for the seismic response control of structures, excessive auxiliary mass displacements must be avoided even under a high level of excitation, which becomes a critical factor in the event of strong earthquakes. The control algorithm for the full-scale multi-story steel frame test structure at Disaster Prevention Research Institute, Kyoto University, takes advantage of a nonlinear control scheme based on a variable gain method to overcome this difficulty. The nonlinear control used in the test achieves effective use of AMD with a limited displacement range of the auxiliary mass for structures under various levels of seismic input. The structural control test is conducted to verify the efficiency of the variable gain control scheme when used with the full-scale test structure. The test result using a seismic record shows the effectiveness of the control method, especially when subjected to a strong earthquake excitation.
Implementation of Non-Reflecting Boundaries in a Space-Time Finite Element Method for Structural Acoustics
Authors: Thompson Lonny L. 
Published: February 2021

Abstract
This paper examines the development and implementation of second-order accurate non-reflecting boundary conditions in a time-discontinuous Galerkin finite element method for structural acoustics in unbounded domains. The formulation is based on a multi-field space-time variational equation for both the acoustic fluid and elastic solid together with their interaction. This approach to the modeling of the temporal variables allows for the consistent use of high-order accurate adaptive solution strategies for unstructured finite elements in both time and space. An important feature of the method is the incorporation of temporal jump operators which allow for discretizations that are discontinuous in time. Two alternative approaches are examined for implementing non-reflecting boundaries within a time-discontinuous Galerkin finite element method; direct implementation of the exterior acoustic impedance through a weighted variational equation in time and space, and indirectly through a decomposition into two equations involving an auxiliary variable defined on the non-reflecting boundary. The idea for the indirect approach was originally developed in (Kallivokas, 1991) in the context of a standard semi-discrete formulation. Extensions to general convex boundaries are also discussed — numerical results are presented for acoustic scattering from an elongated structure using a first-order accurate boundary condition applied to an elliptical absorbing boundary.
Nonlinear Wave Propagation in Elastic Submerged Cables
Authors: Behbahani-Nejad M. , Perkins N. C. 
Published: February 2021

Abstract
This paper analyzes the coupled nonlinear tangential-normal waves that propagate along underwater cable suspensions. Taken with the recently developed linear theory governing the in-plane structural waves (3) and an analysis of nonlinear out-of-plane waves for submerged cables (2), this investigation contributes further understanding toward a nonlinear three-dimensional theory for wave propagation along fluid loaded cables. The nonlinearities present in the in-plane model render the cable/fluid model intractable by exact analytical methods. A numerical solution is pursued in this study using finite difference algorithms. To this end, an infinite cable domain is divided to two sub domains, namely an interior (finite computational) domain and exterior (infinite far field) domain. Closed-form solutions for the approximate linear theory are employed for the far field in constructing nonreflecting boundary conditions for the computational domain. Numerical results highlight the governing role of nonlinear hydrodynamic drag for underwater cable suspentions.
Analysis of Dynamic Force Between Teeth Walls in Scroll Compressors by Elastic Contact Modelling
Authors: Suzuki Takayuki , Sato Kazuhiro 
Published: February 2021

Abstract
The new dynamic behavior model for excited force in scroll compressors has been developed. We were not satisfied with the results of our previous analysis model as the contact area between the teeth walls of the scrolls was limited to one point. In our new analysis model, we consider the contact at several points and the linear elastic model at contact points. Force excited at contact points between the teeth walls of the two scroll elements contributes to the level of noise radiated from the scroll compressors. By using our model, the excited force at contact points between each element in the scroll compressors can be calculated and therefore aid us in our efforts at noise and vibration reduction. This paper describes the equation of the dynamic behavior model derived from the motion of elements : an orbiting scroll, an oldham ring, a slider block, and a crank shaft. Also the theoretical and experimental results are discussed.
Experimental and Numerical Studies of Friction-Induced Oscillations of a Pin-on-Disk Apparatus
Authors: Tworzydlo W. W. , Hamzeh O. N. , Zaton W. , Judek T. , Loftus H. 
Published: February 2021

Abstract
The paper presents coordinated experimental and numerical studies of friction-induced vibrations of a pin-on-disk apparatus. The primary objective is to verify and expand the understanding of friction-induced vibrations, and to confirm validity of the analytical predictive technology. A special experimental apparatus was built, which possesses desirable qualities of mechanical simplicity and controllable dynamic characteristics. For this apparatus, an analytical model was devised, taking into consideration both the dynamics of the mechanical system and strongly nonlinear constitutive properties of the contact interface. These properties were determined through asperity-based homogenization approach. By variation of selected details of the apparatus, both stable and unstable configurations of the system were devised and tested. The experimental observations correlate very well with analytical predictions of dynamic instability and of limit cycle oscillations.
Periodic Optimal Control of Dampers
Authors: Kasturi Prakash S. , Dupont Pierre E. 
Published: February 2021

Abstract
Optimal control of dampers has been proposed to mitigate vibration effects in mechanical systems. In many cases, systems are subject to periodic forcing and the goal is to maximize the energy dissipated by the damper. In contrast to prior work utilizing instantaneous or infinite-time-horizon optimization, this paper employs periodic optimal control to maximize the energy dissipated per cycle. For single degree of freedom systems in which the maximum allowable control effort is of the same order as the forcing magnitude, a state-dependent singular control law is shown to deliver maximum energy dissipation. Alternate control laws are proposed for situations when rattlespace requirements dictate damper displacements other than that of the singular solution.
Light-Induced Non-Contact Actuation and Control With Photostrictive Actuators
Authors: Tzou H. S. , Liu B. J. 
Published: February 2021

Abstract
Non-contact light activated distributed opto-electromechanical actuators represent a new class of precision distributed actuator which are based on the photodeformation process and controlled by high energy lights, e.g., lasers and ultra-violet lights. Fundamental opto-thermo-electromechancial constitutive relations are discussed and formulations of optically induced control forces and moments introduced. Mathematical modeling and analysis of distributed opto-electromechanical shell actuators are presented. A generic distributed photo-actuation theory is proposed and the closed-loop opto-thermo-electromechancial equations of circular cylindrical shells are derived. The systems equations reveal the couplings among elasticity, photodeformation, pyroelectricity, and thermoelasticity. Active distributed control of flexible cylindrical shells using segmented distributed opto-electromechanical shell actuators are investigated and the control effectiveness is evaluated. Membrane and bending control effects are evaluated. Time history analyses of independent modal control reveal that the Lyapunov control is more effective than the proportional feedback control.
Vibration Control of a Multi-Layer Piezoelectric Cylindrical Shell
Authors: Qiu Jinhao , Tani Junji 
Published: February 2021

Abstract
Equations of motion for multi-layer piezoelectric cylindrical shells and the equations of the integrated piezoelectric sensors are derived. The state equation is obtained by solving the equations of motion with modal expansion method. The feedback control, feedforward control, and their combination are applied in the control of forced vibration of the piezoelectric cylindrical shell with integrated sensor and actuators. The simulation and experimental results show that good control effectiveness can be obtained by using the integrated piezoelectric sensor and actuators in conjunction with the combination of feedback and feedforward control methods.
Actuator Placement in Smart Structures by Discrete-Continuous Optimization
Authors: Gabbert U. , Schulz I. , Weber C.-T. 
Published: February 2021

Abstract
Multi-functional smart materials, which can be used as conventional load bearing structural elements as well as actuators and sensors — e.g. as part of a multi-layered composite — in conjunction with suitable control systems are the basis of the development of adaptive structural systems for shape control, vibration damping etc. The effectiveness of an adaptive structural system depends decisively on the placement of the actuators and sensors. In the present paper a general mathematical method for the determination of an optimal actuator placement is given, which takes advantage of additional mechanical information about the structural behavior, i.e. the sensitivity of the system with respect to the design variables. Following concepts of geometry and topology optimization in the present paper an optimization strategy is presented for the simultaneous determination of the discrete positions of the actuators as well as the continuous parameters of the control law. For the verification of the optimization strategy a complete variant test of the ten-bar-truss problem is analyzed. The results of the optimization strategy match the results of the variant test.
On Experiments of Adaptive Control for Structure Vibration
Authors: Ma Kougen , Peng Fujun , Gu Zhongquan , Chen Xi 
Published: February 2021

Abstract
The paper summarized the experimental studies of adaptive structure vibration control in Nanjing University of Aeronautics and Astronautics (NUAA). Two kinds of experimental setups are constructed, i.e. an adaptive feedback control setup and an adaptive feedforward control setup. The former is used for free vibration control, and the control law is realized by the Intel 80X87 floating point processor. A Single Input and Single Output (SISO) control strategy is presented and extended to Multi-Input and Multi-Output (MIMO) systems. Its adaptabilities to the locations of sensors and actuators are also evaluated. The latter is suitable for forced vibration control, e.g. periodic vibration control and random vibration control. Its theoretical base is adaptive filtering theory. Its data acquisition and control law calculation are finished by the master/slave computers. The master computer — an IBM PC or a compatible PC — is responsible for data acquisition, and the slave computer — the TMS320C30 Digital Signal Processor (DSP) — calculates the control law. The results for both periodic vibration control and random vibration control are shown.
Optimal Tracking Servo-System by Means of Sliding Mode Control
Authors: Uchida Hiroaki , Nonami Kenzo 
Published: February 2021

Abstract
This paper dealt with design scheme of sliding mode optimal tracking control in which the hyperplane is designed to follow the desired trajectory without time-delay. At first, we designed the servo system by applying conventional optimal tracking control, H1 and H∞ optimal tracking control. Secondly, we show the design method of sliding mode optimal tracking control. Thirdly, we carried out the simulation to verify the validity of the design method. In the simulation, three patterns were examined by using H2 norm. The trajectory following and the robust performance in the difference of the design methods were clarified by the simulations. Finally, we applied these control methods to a quadruped locomotion robot.
Sliding Mode Control of Motion and Vibration Without Sensors
Authors: Ohnuki Osamu , Nonami Kenzo 
Published: February 2021

Abstract
In this paper, a method to realize the motion and vibration control without sensors is proposed. Sensorless control is generally realized by estimating the state of the system from the measured current in the actuator by means of an observer. It is possible to estimate all state variables because of dynamic interaction in the controlled object. Then we realize nonlinear robust control system based on the observer. In this paper, first we formulate sensorless control system. As controlled objects we deal with a multi-degree-of-freedom structure as a vibration control problem and a single link robot arm as a motion control problem, respectively, and we carry out numerical simulations. Moreover, we also verify the possibility of realization of sensorless control by experiments.
Control System Design of Frequency-Feedback Magnetic Bearings
Authors: Mizuno Takeshi , Araki Kenji , Namiki Hirotaka 
Published: February 2021

Abstract
The structures and features of control system are discussed for active magnetic bearings (AMBs) with frequency type of displacement sensors. The control systems are classified according to the signal conversions performed there. One of them uses a counter circuit for converting the frequency to a digital format, and the converted signal for digital signal processing. It is also pointed out that self-sensing operation can be realized by using hysteresis amplifiers because their switching rates are sensitive to load impedance. A digital self-sensing AMB, which uses a counter circuit for interface and hysteresis amplifiers for energizing the electromagnets, is manufactured for experimental study. The experimental results show that accurate suspension can be achieved with the proposed digital control system.
Real-Time Recursive Least Squares Identification and Control of Lathe Chatter: Implementation and Performance Issues
Authors: Zhang Shilong , Ousterhout Karl B. 
Published: February 2021

Abstract
In most machining processes, the large amounts of energy that are required to accomplish the machining can lead to the development of self sustained vibrations (chatter). If chatter does develop, it severely limits the production capabilities of the machine tool — typically resulting in longer production cycles and increased tool wear rates. In this paper, a method of controlling lathe chatter is proposed, simulated, and experimentally verified. To eliminate the chatter, a feed-forward digital controller and electro-hydraulic cutting tool actuator is employed. To account for the time varying nature of the tool/workpiece dynamics, a recursive least squares parameter estimation technique is used to estimate the dynamics of the machining process in real-time. These parameter estimates are then used by the digital controller to control the cutting force at the cutting tool/workpiece interface.
Using Phase Space Reconstruction to Track Parameter Drift in a Nonlinear System
Authors: Cusumano J. P. , Chelidze D. , Hecht N. K. 
Published: February 2021

Abstract
A model-based experimental method for tracking parameter drift in nonlinear dynamical systems is described. Local linear tracking models are constructed using data sampled over a fast time scale. These models are used to analyze data from systems with parameters which evolve over a slow time scale according to a “hidden” rate law. The method is applied to a numerical study of a nonlinear electrical circuit with a variable resistance as the drifting parameter. The mean-square tracking model prediction error is shown to follow successfully both ramped and sinusoidal parameter variations, suggesting that, at least in the cases studied, the method provides an invertible mapping between the parameter space and the observable space. Thus it should be possible to extract rate information about hidden drift, a requirement for true prediction.
The Double Seesaw Oscillator in a Windfield: Theory and Experiments
Authors: van der Burgh A. H. P. , Haaker T. I. , van Oudheusden B. W. 
Published: February 2021

Abstract
In this paper the dynamics of an oscillator with two degrees-of-freedom of a double seesaw type in a windtunnel is studied. Model equations for this aeroelastic oscillator are derived and an analysis of these equations is given for the non-resonant case. A typical result is a (local codimension two) bifurcation which describes the transfer from the unstable equilibrium state to one of the two normal modes of the oscillator. Some experimental results are presented from which on may conclude that more accurate model equations should be developed.