bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Survey of Part Presentation, Feeding and Fixturing in Automated Assembly Systems
Authors: Yeong Mengyik , Ruff Larry , De Vries Warren R. 
Published: April 2021

Abstract
The development of feeding, presentation and fixturing systems are essential in achieving the integration of design and manufacture. A bibliography of over 150 items serves as the basis of this survey of trends in the development of these systems for assembly. Recent technical literature, indicative of academic research and available commercial hardware systems are reviewed. While the emphasis of this paper is on presenting primarily mechanical solutions to the part feeding, presentation and fixturing problem, many papers which focus on AI, vision and knowledge-based systems are also included in the bibliography. In reviewing this literature, it is found that while many solutions have been presented, more work is needed toward fundamental understanding of the mechanics of feeding, presenting and fixturing, so that analysis and modeling can replace some of the re-design steps. This will aid in reducing the lead time by allowing systems to be designed from CAD data, rather than having to wait for prototype parts.
A Motion Synthesis Technique for Control of Planar Robots
Authors: Shirkhodaie Amir , Soni A. H. 
Published: April 2021

Abstract
Planar algebraic curves (polynomial, parametric type) are frequently required to be generated to manufacture specific geometric surface characteristics of the machine parts. Precision, accuracy, and speed are in general prime requisites. However, flexibility also becomes mandatory in today’s industry environment. A planar three degree of freedom robot is designed and fabricated with a built in forward and inverse kinematic algorithm. The robot may be programmed to generate planar enveloping curves where in the generator (tool) is an infinite line. Several examples are presented in this paper to illustrate the forward and inverse design of this particular planar robot for generation of algebraic curves.
Redundancy Compensation in Control of Multiple Arms
Authors: Shirkhodaie Amir , Soni A. H. 
Published: April 2021

Abstract
During manipulation of an object grasped at N locations by end-effectors of N robots, relaxation of assumption on invariant grasping locations of end-effectors Is too realistic. When coordinating end-effectors take infinitesimal displacements at the contact grasping locations with a rigid object, a slippage occurs which undesirably induces some redundancy in closed form kinematics/dynamics formulation of the entire robotic system. Particularly, in force/position control of multiple coordinating robot arms such an affect produces Inevitable impulsive reaction forces/moments which need to be compensated for in global control strategy of the system. In this paper, we have presented a control strategy with a Dynamic Redundancy Compensator (DRC) for cartesian space control of the coordinating multiple robots manipulating a common object. The proposed control scheme embeds dynamics of the individual coordinating robot arms and dynamically is capable to compensate for the kinematic/dynamic redundancies while preserving optimum forces/torques distribution between the end-effectors of robot arms. The results of study has been demonstrated on control of two robot arms manipulating a common object through prescribed coordinated motions.
Distributed Piezoelectric Neurons and Muscles for Shell Continua
Authors: Tzou H. S. 
Published: April 2021

Abstract
Conventional shell continua are passive, which do not possess any sensation and action/reaction capabilities. In this paper, distributed piezoelectric layers coupled with conventional elastic shell distributed systems are used as distributed “neurons” (sensors) and “muscles” (actuators) for structural monitoring and actuation of shells. New theories on distributed “neural” sensation and actuation of shells are developed based on a generic shell continuum coupled with piezoelectric neurons and muscles. Open and closed loop system dynamic equations are also derived. The system equations are further transferred to state equations. The derived theories can be directly simplified to a broad class of geometries, cylindrical shells, spherical shells, conical shels, zero-curvature shells (i.e., plates: rectangular, circular, etc.), beams, etc. Applications of the theories to a cylindrical shell using four system parameters, two Lame’s parameters and two radii of curvature, are demonstrated.
Theory on Hexagonal Symmetrical Piezoelectric Thick Shells Applied to Smart Structures
Authors: Tzou H. S. , Zhong J. P. 
Published: April 2021

Abstract
Smart piezoelectric structures, conventional passive materials integrated with piezoelectric sensors, actuators and control electronics, have great potentials in many engineering applications. This paper is devoted to a new theoretical development of generic piezoelectric shell distributed systems. System electromechanical dynamic equations, three translational coordinates and two rotatory coordinates, and boundary conditions, electric and mechanical, for a thick piezoelectric shell continuum with symmetrical hexagonal structure (Class C6v = 6mm) are derived using Hamilton’s principle and linear piezoelectric theory. The thick shell system equations are simplified to thin piezoelectric shells using Kirchhoff-Love’s assumptions. Converse effect induced electric forces/moments and boundary conditions can be used to alter system dynamics via open or closed loop control systems. Applications of the theories to a thick plate and a spherical shell are demonstrated in case studies.
Piezoelectric Modal Sensor/Actuator Design for Monitoring/Generating Flexural and Torsional Vibrations of Cylindrical Shells
Authors: Sung C. K. , Chen C. F. , Chen S. G. 
Published: April 2021

Abstract
This paper presents a methodology for designing piezoelectric sensors/ actuators in an application to monitor/generate flexural and torsional vibrations of cylindrical Shells. Based upon the classical laminate theory the equations of the electro-mechanical interactions, the constitutive, and the strain-displacement relations of piezoelectric composite cylindrical shells are derived. With these relations the piezoelectric sensor and actuator equations of the cylindrical shell are then developed. The modal sensors/actuators fabricated with PVDF embedded in the composite cylindrical shell capable of monitoring and generating vibrations of a particular mode or several combined modes are also developed. Finally, an experimental rig is designed to generate both the flexural and the torsional vibrations of a. circular cylindrical shaft for examining the capabilities of the modal sensors.
Piezoelectric Devices for Vibration Control on Flexible Structures
Authors: Legrain I. , Destuynder P. 
Published: April 2021

Abstract
A coupled numerical and experimental study, concerning the vibration control, on flexible structures by piezoelectric devices, is presented in this paper. More precisely we studied two cases of structure, a beam and a plate, in several configurations of excitation. The implemented controls, which are closed loop controls, concern always the first vibration modes.
Deflection and Force Experimental Verification of a Semicircular Polymeric Piezoelectric Actuator
Authors: Brei Diann , Blechschmidt James 
Published: April 2021

Abstract
This paper describes a manufacturing technique used to produce semicircular piezoelectric prototypes and the measurement techniques and results for three types of experiments performed to confirm the theoretical models. Since the microactuator design was new, unique and new methods of manufacturing had to be developed. This technique is a four step process that produces a prototype with a thin bonding layer with no bubbles. This prototype was tested and evaluated using three experiments: deflection-voltage, force-voltage, and force-deflection experiments. These experiments verified the theoretical model are correct.
Sensor Mechanics of Distributed Shell Convolving Sensors Applied to Flexible Rings
Authors: Tzou H. S. , Zhong J. P. 
Published: April 2021

Abstract
Observation spillover can introduce system instability to undamped distributed structural systems. This problem can be prevented via modal filtering using distributed piezoelectric modal sensors which are spatially shaped and convoluted such that they are only sensitive to specific modal mode(s). In this paper, detailed electromechanics — sensor mechanics — of spatially distributed piezoelectric shell convolving sensors are analyzed and results presented. It is observed that sensor sensitivity can be classified into two components: 1) the transverse modal sensitivity and 2) the membrane modal sensitivity in which the former is primarily contributed by bending strains and the later is by membrane strains. Design of spatially distributed cosine-shaped convolving sensors for ring structures is proposed and evaluated. Parametric studies suggest that the transverse sensitivity increases and the circumferential sensitivity remained constant when the ring becomes thicker. Both transverse and circumferential sensitivities increase when the piezoelectric layer becomes thicker or with higher piezoelectric constants.
Colocation: Design Constraints for Distributed and Discrete Transducers
Authors: Burke Shawn E. , Hubbard James E. , Meyer John E. 
Published: April 2021

Abstract
Colocated sensors and actuators offer significant robustness and design benefits in distributed parameter vibration control. The concept of colocation is extended to distributed transducers, and combinations of distributed and discrete transducers, affixed to self-adjoint distributed plants. It is shown that sensors and actuators are colocated only when they have both physically coincident spatial apertures and their “spatial derivative orders” are equal: these constraints are expressed mathematically as an integral equation. In satisfying these constraints the resulting transducer-augmented plant, if open-loop stable, is minimum phase. These results are demonstrated by transducer placement studies.
Optimal Placement of Actuators in the Precision Control of Truss Structures
Authors: Das S. K. , Utku S. , Chen G. S. , Wada B. K. 
Published: April 2021

Abstract
Actuator placement criteria in truss structures are based on satisfying two goals: (1) precision control (displacement control) of precision points, and, (2) prestressing control (i.e., creation of initial stresses) to counteract joint looseness. It is shown that stress-free exact displacement control is possible in (a) statically determinate trusses using as many actuators (q) as the number of independent degrees of freedom at precision points (p), i.e., q = p; (b) in statically indeterminate trusses using q = p + r actuators, where r is the degree of redundancy. Using (a) q &lt; p actuators in statically determinate trusses will allow only for approximate displacement control, and, (b) using q &lt; p+r actuators, in statically indeterminate trusses, will allow for: (1) exact, stress-induced displacement control if q &gt; p, with q-p actuators to relieve stress as best as possible; (2) approximate, stress-free displacement control if p &gt; q &gt; r, or, (3) approximate, stress-induced displacement control if q &lt; p and q &lt; r. For prestressing control using actuators, the structure must be indeterminate at least to degree 1. If indeterminate to degree r, it is either possible to (a) exactly control a maximum of r components of member forces (using q = r actuators), or, (b) exactly control all member forces, provided they lie in the column space of the null matrix of the coefficient matrix of bar forces in the force equilibrium equations of the joints (using q = r actuators). By using q &lt; r actuators, it is possible to exactly control only q components of member forces. It is also shown that, with sufficient number of actuators, prestressing control with no disturbance to precision points is possible. Optimal actuator placement schemes are studied for some of the above cases of precision control and prestressing control, based on objectives which are specific to each case. In statically indeterminate truss structures the optimal placement criteria and techniques differ depending on whether the primary determinate structure is known or not. A suboptimal actuator placement solution to the global optimization problem, combining the objectives of displacement control and prestressing control, is suggested (for the case q &lt; p and q &lt; r) by combining the results of the separate optimization problems (displacement control, prestressing control); the suboptimal solution is improved (with respect to global optimum) by iteration.
An Experimental Study of Tendon Vibration Control System for Flexible Space Structures
Authors: Murotsu Yoshisada , Okubo Hiroshi , Senda Kei 
Published: April 2021

Abstract
The idea of a tendon vibration control system for a beam-like flexible space structure has been proposed. To verify the feasibility of the concept, an experimental tendon control system has been constructed for the vibration control of a flexible beam simulating Large Space Structures (LSS). This paper discusses modeling, identification, actuator disposition, and controller design for the experimental system. First, a mathematical model of the whole system of the beam and tendon actuator is developed through a finite element method (FEM). Second, to obtain an accurate mathematical model for designing a controller, unknown characteristic parameters are estimated by using an output error method. The validity of the proposed identification scheme is demonstrated by good agreement between the transfer functions of the experimental system and an identified model. Then, disposition of actuators is discussed by using the modal cost analysis. Finally, controllers are designed for SISO and MIMO systems. The feasibility of the proposed controller is verified through numerical simulation and hardware experiments.
Transient Analysis on Turbo Engine Combustion Flow
Authors: Drakatos P. A. , Giannaras G. , Argyriou A. , Andriotis T. 
Published: April 2021

Abstract
One of the most important technical problem is the moniroting of the combustion flow, concerning the aircraft turbo-engine during its continuous operation.
Considering the combustion process as a dynamic excitation, we measure the noise and the vibration on chosen points on the engine. By doing that we come to conclusions concerning the combustion flow. In this experimental work appear the spectra of the noise and vibration measurements as a parameters of engine revolutions (R.P.M.).
The spectra of random combustion forces and spectra of noise and vibration borne noise structure are investigates using transient analysis.
Their analysis by P.C. and the construction 3-D diagrams which combine the noise level, the vibration level and the R.P.M., give us important information about the interdependance of the above sizes and the combustion flow. The measurements take place on the F-104 G Starfighter aircraft with the General Electric-J79 turboengine, which is the oldest military aircraft in today use.
The Quantification of Internal Noise Levels and Wall Pressure Spectra in Industrial Gas Pipelines
Authors: Norton M. P. , Pruiti A. 
Published: April 2021

Abstract
This paper addresses the issue of quantifying the internal noise levels/wall pressure fluctuations in industrial gas pipelines. This quantification of internal noise levels/wall pressure fluctuations allows for external noise radiation from pipelines to be specified in absolute levels via appropriate noise prediction models. Semi-empirical prediction models based upon (i) estimated vibration levels and radiation ratios, (ii) semi-empirical transmission loss models, and (iii) statistical energy analysis models have already been reported on by Norton and Pruiti 1,3 and are not reported on here.
The Importance of Transient Analysis on Internal Combustion Engines Structures
Authors: Drakatos P. A. , Haidas S. 
Published: April 2021

Abstract
Because of difficulties of applying Transient Analysis in complex structure we use a set up of instruments by exploiting the experimental results of known structures of engines.
Considering the combustion process as a dynamic excitation, we measure the noise and teh vibration on chosen points on a Spark Ingnition (S.I) engine and a Compression Ingnition engine (C.I). By doing that we come no conclusions concerning the combustion flow.
In this experimetnal work appear the spectra of the noise and vibration measurements in connection with the R.P.M. fo the engine. From the comparison between the spectra, we extract important results concerning the chanage of the combustion flow in every different type of engine in several stages.
The mesurements have been taken on a S.I. and C.I. engine in Special Engineering Laboratory.
The Use of Noise and Vibration Analysis on the Hydraulic Networks
Authors: Drakatos P. A. , Drakatos S. P. 
Published: April 2021

Abstract
This paper is concerned with Analysis of Vibration and Noise in a hydraulic networks. In the analysis it is tried to find the discrete frequencies. So, we are able to recognize the damages or to redesign the system. The most important effectiveness on the system ought to the flow in the phase of vorticity.
Research on Structure Optimization of the Engine Using Noise and Vibration Analysis
Authors: Drakatos P. A. , Drakatos S. P. 
Published: April 2021

Abstract
One of the useful problems in the engines is its operation optimization.
During combustion we use mixture of oil and soy-oil in a stroke internal combustion engine (S.I.C.E. during its continuous operation.
Considering the combustion process as a dynamic excitation, we measure the noise and the vibration on chosen points on a S.I.C.E. By doing that we come to conclusions concerning the combustion flow.
In this experimental work appear the spectra of the noise and vibration measurements in connection with the R.P.M. of the engine. The comparison between the diagrams in the case of the simple combustion and the comubstion of the mixture give us important information about the influence of mixutre in the S.I.C.E.
So, we can have results on the structure optimization of the engines.
Research on Air-Burned Gases Compressible Flow As a Function of Engine Sound Spectrum
Authors: Drakatos P. A. , Giannaras G. , Argyriou A. , Andriotis T. 
Published: April 2021

Abstract
The aerodynamic flow resulting from engine combustion flow is researched.
Considering the combustion process as a dynamic excitation, we measure the noise and the vibration on chosen points on the burned-gases flow. By doing that we come to conclusions concerning the combustion flow and the after-burning.
In this experimental work appear the spectra of the noise measurements in connection with the R.P.M. of the engine. It is tried to find the function of air compressible flow concerned with mechanical situation and combustion flow of the engine.
The comparison between the spectra give us important information about the interdependance between the noise and the combustion flow in the combustion chamber and the after burner. The measurements take place on several situation engine.
Shock and Sine Response of Rigid Structures on Nonlinear Mounts
Authors: Dufour R. , Hagopian J. Der , Pompei M. , Garnier C. 
Published: April 2021

Abstract
The dynamic environment of embarqued structures such as radars or more generally electronic equipments consists of impacts, sine and large power spectrum excitations. Under these real conditions and amongst different kinds of isolation, the passive damper with nonlinear parameters can provide good performances. This paper is concerned with the dynamic behavior of rigid bodies on highly nonlinear mounts. The numerical simulation and the experiment carried out, show that the load-deflection behavior of the dampers have to be slightly ajusted with respect to impact vibrations to obtain a well designed behavior.
Analysis of Base Excitation As an Uncertain Function With Specified Bounds on it and its Derivatives
Authors: Elishakoff Isaac , Pletner Baruch 
Published: April 2021

Abstract
In this paper the uncertainty in the base excitation of a lumped parameter structure is model led_as a function with specified bounds. Namely, the bounds are imposed on base acceleration, velocity or displacement. The investigation focuses on how global knowledge on the response is modified when global information on the excitation is increased. In particular, the maximum possible response the structure may develop is evaluated under the assumption that only the bound on base acceleration is known; then the maximum response is modified under the assumption that in addition to the base acceleration bound, the bounds on base velocity and displacement are specified.
Dynamic Properties of Rigid Body and Supports From Vibration Measurements
Authors: Pandit Sudhakar M. , Yao Ying-Xian , Hu Zhi-Quan 
Published: April 2021

Abstract
A method is presented to get the dynamic characteristics of a multi-DOF rigid body structure from the measured vibration data. These characteristics include the mass, center of gravity, moment of inertia and the principal axes of the body, stiffness, damping, the center of stiffness in any direction, moment of stiffness, center of damping and moment of damping, and the principal axes of the supports. The method is capable of representing structures with various DOFs, from 2 up to 6. The mass M, stiffness K, and damping C (or M−1K and M−1C) matrices are obtained first based on measured vibration data by Data Dependent Systems (DDS) methodology which is accurate even for highly damped structures. Relationships between the physical characteristics and these matrices have been derived so that the physical characteristics can be obtained by solving simultaneous linear equations. It is also possible to determine the characteristics up to 5 individual springs and dashpots to provide a basis for improvement in the structure’s performance.
Dynamic Analysis of Engine-Mount Systems
Authors: Ashrafiuon Hashem , Nataraj C. 
Published: April 2021

Abstract
This paper examines the forced response of an airplane engine supported by an elastic foundation. It is assumed that the vibrations of the engine and the foundation are small enough such that the equations of motion are linear. The engine is modeled as a rigid body connected to the foundation by standard industrial rubber mounts which act as three dimensional springs with a significant amount of hysteresis damping. Three fundamental models of the foundation are considered: rigid, statically flexible, and dynamically flexible. In the flexible cases, the foundation is modeled as a clamped circular plate, infinite plate, or any structure identified by a finite element stiffness matrix. In all cases, the mass, stiffness, and damping matrices of the engine-mount system are constructed and the frequency response to the rotating unbalance is determined. For the infinite and clamped circular plate cases, analytical methods are used to determine the real and imaginary parts of the flexibility matrix at different frequencies in response to the harmonic forces transmitted to the plate through the rubber mounts. It is shown here that the foundation elasticity may have a significant effect on the engine vibration and the mounting forces transmitted from the engine to the structure. It is also shown that only the dynamic model of the foundation is able to capture the correct response of the system at frequencies close to the foundation’s natural frequencies.
Vibration Analysis Methods Applied to Forensic Engineering Problems
Authors: Saczalski Kenneth J. , Loverich Eugene B. 
Published: April 2021

Abstract
Forensic engineering problems are reviewed to demonstrate how vibration analysis methods can be utilized in certain instances to determine cause of system failures and injury mechanics associated with certain vehicular accidents. A brief overview of injury criteria and biomechanical analysis methods for evaluation of motor vehicle occupant kinematics induced by shock impact loadings is also included.