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Missouri University of Science and Technology

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Articles 1501 - 1530 of 2222

Full-Text Articles in Mechanical Engineering

Utilization Of A Piezoelectric Polymer To Sense Harmonics Of Electromagnetic Torque, Jason Neely, Steven Pekarek, Daniel S. Stutts, Philip Beccue Sep 2003

Utilization Of A Piezoelectric Polymer To Sense Harmonics Of Electromagnetic Torque, Jason Neely, Steven Pekarek, Daniel S. Stutts, Philip Beccue

Mechanical and Aerospace Engineering Faculty Research & Creative Works

In this paper, the use of a piezoelectric polymer material to measure the harmonics of electromagnetic torque produced by a permanent magnet synchronous machine is described. The advantages of the polymer include low cost, durability, and flexibility. In addition, wide-bandwidth sensors are relatively easy to design and couple to drive system hardware for harmonic evaluation or to use in feedback-based control. To illustrate the use of the polymer, the electrical and mechanical properties of three sensors are described. The results of time-domain simulation and hardware experiments are used to validate that the voltage obtained from the sensors is linearly related …

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Application Of A Diagnostic Tool In Laser Aided Manufacturing Processes, Sashikanth Prakash, Mallikharjuna Rao Boddu, Frank W. Liou Aug 2003

Application Of A Diagnostic Tool In Laser Aided Manufacturing Processes, Sashikanth Prakash, Mallikharjuna Rao Boddu, Frank W. Liou

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Lasers play a vital role in producing parts with high dimensional accuracy, strength and quality in today's rapid prototyping industry. In the process of Laser Metal Deposition, many problems are encountered where the part quality does not meet the required standards. This could be due to the nonconformity of control parameters or unnecessary interactions between the control factors. This paper discusses the implementation of Dr. Genichi Taguchiï's optimization techniques using Design of Experiments (DOE) where a series of fractional factorial experiments are performed on the laser deposition process. The results from these experiments are evaluated with respect to the rate …

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Modeling For The Control Of The Laser Aided Manufacturing Process (Lamp), Mallikharjuna R. Boddu, Vishnu P. Thayalan, Robert G. Landers Aug 2003

Modeling For The Control Of The Laser Aided Manufacturing Process (Lamp), Mallikharjuna R. Boddu, Vishnu P. Thayalan, Robert G. Landers

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Many state-of-the-art Rapid Prototyping (RP) technologies adopt lasers to fabricate 3-D solid parts by material deposition in layers. The ability of these RP technologies to control the process requires a thorough understanding of the process mechanics. This paper presents the analysis of an analytical, dynamic model explaining the complex phenomenon of Laser Aided Manufacturing Process (LAMP). The equilibrium of the dynamic model is analyzed and dynamic simulations are performed to determine its stability characteristics. This model forms the basis for the real-time control of the LAMP.

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Process Control Of Laser Metal Deposition Manufacturing -- A Simulation Study, Robert G. Landers Aug 2003

Process Control Of Laser Metal Deposition Manufacturing -- A Simulation Study, Robert G. Landers

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The laser metal deposition process is a rapid manufacturing operation capable of producing functional prototypes with complex geometries and thin sections. This process inherently contains significant uncertainties and, therefore, extensive experimentation must be performed to determine suitable process parameters. An alternative is to directly control the process on-line using feedback control methodologies. In this paper, a nonlinear control strategy based on feedback linearization is created to automatically regulate the bead morphology and melt pool temperature. Extensive simulation studies are conducted to validate the control strategy.

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Signal Mast Arm Fatigue Failure Investigation, Genda Chen, Michael G. Barker, Lokeswarappa R. Dharani, Christopher W. Ramsay May 2003

Signal Mast Arm Fatigue Failure Investigation, Genda Chen, Michael G. Barker, Lokeswarappa R. Dharani, Christopher W. Ramsay

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The Missouri Department of Transportation (MoDOT) has discovered and documented failures in several cantilever mast arms in the recent years. The failures were primarily by fatigue at the weld of the arm to the base plate attached to the mast. With over 6000 mast arms in service in Missouri, the failures raised concerns with the existing mast arm inventory and future mast arm design. This report presents findings from an effort to determine the cause of unexpected cracking in Missouri mast arms. Three causes of premature failure were investigated: the stress ranges experienced at the weld detail were higher than …

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Solvent And Method For Extraction Of Triglyceride Rich Oil, Shubhender Kapila, Paul Ki-Souk Nam, V. J. Flanigan Apr 2003

Solvent And Method For Extraction Of Triglyceride Rich Oil, Shubhender Kapila, Paul Ki-Souk Nam, V. J. Flanigan

Chemistry Faculty Research & Creative Works

The present invention relates to a solvent for use in extracting oil from an oil bearing material, such as soybeans, with the solvent resulting in the selective extraction of a triglyceride rich oil, which contains 95% or greater triglycerides and non-polar constituents, with the solvent comprised of a hydrocarbon, preferably hexane, and a fluorocarbon, so that the solvent has a viscosity less than 2.6 centipoise and a polarity of less than 0.1. The present invention also relates to a method of using the solvent to extract the triglyceride rich oil, with the method including preferably extracting the oil at a …

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Comparison Of 3-, 5-, And 6-Phase Machines For Automotive Charging Applications, B. Zhang, Hua Bai, Walter Eversman, Ronald J. Krefta, Duane J. Buening, Steven Pekarek, Gregory R. Holbrook Jan 2003

Comparison Of 3-, 5-, And 6-Phase Machines For Automotive Charging Applications, B. Zhang, Hua Bai, Walter Eversman, Ronald J. Krefta, Duane J. Buening, Steven Pekarek, Gregory R. Holbrook

Mechanical and Aerospace Engineering Faculty Research & Creative Works

In this paper, the performance of a 5-phase claw-pole machine/converter system is compared with those of 3-phase and 6-phase systems of the same volume. It is shown that the acoustic output of the 5-phase machine compares favorably with that of the 6-phase machine and is much lower than that of the 3-phase machine over a majority of the operating range. In addition, the output current produced by the 5-phase machine Is, in general, 6-8% higher than those of the 3-phase and 6-phase machines. These results suggest that for maximizing power density while minimizing cost and acoustic noise, 5-phase machines provide …

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A Single-Element Tuning Fork Piezoelectric Linear Actuator, J. Satonobu, K. Nakamura, S. Ueha, Daniel S. Stutts, James R. Friend Jan 2003

A Single-Element Tuning Fork Piezoelectric Linear Actuator, J. Satonobu, K. Nakamura, S. Ueha, Daniel S. Stutts, James R. Friend

Mechanical and Aerospace Engineering Faculty Research & Creative Works

This paper describes the design of a piezoelectric tuning-fork, dual-mode motor. The motor uses a single multilayer piezoelectric element in combination with tuning fork and shearing motion to form an actuator using a single drive signal. Finite-element analysis was used in the design of the motor, and the process is described along with the selection of the device's materials and its performance. Swaging was used to mount the multilayer piezoelectric element within the stator. Prototypes of the 25-mm long bidirectional actuator achieved a maximum linear no-load speed of 16.5 cm/s, a maximum linear force of 1.86 N, and maximum efficiency …

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Approximate Dynamic Programming Based Optimal Neurocontrol Synthesis Of A Chemical Reactor Process Using Proper Orthogonal Decomposition, Radhakant Padhi, S. N. Balakrishnan Jan 2003

Approximate Dynamic Programming Based Optimal Neurocontrol Synthesis Of A Chemical Reactor Process Using Proper Orthogonal Decomposition, Radhakant Padhi, S. N. Balakrishnan

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The concept of approximate dynamic programming and adaptive critic neural network based optimal controller is extended in this study to include systems governed by partial differential equations. An optimal controller is synthesized for a dispersion type tubular chemical reactor, which is governed by two coupled nonlinear partial differential equations. It consists of three steps: First, empirical basis functions are designed using the "Proper Orthogonal Decomposition" technique and a low-order lumped parameter system to represent the infinite-dimensional system is obtained by carrying out a Galerkin projection. Second, approximate dynamic programming technique is applied in a discrete time framework, followed by the …

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How To Establish Successful Cooperative Student Learning Centers For Stem Courses, Ronald James Bieniek, Douglas R. Carroll, Cesar Mendoza, Oran Allan Pringle, Ekkehard Sinn, Kai-Tak Wan, Donald C. Wunsch Jan 2003

How To Establish Successful Cooperative Student Learning Centers For Stem Courses, Ronald James Bieniek, Douglas R. Carroll, Cesar Mendoza, Oran Allan Pringle, Ekkehard Sinn, Kai-Tak Wan, Donald C. Wunsch

Physics Faculty Research & Creative Works

Students learn more if they are actively involved in the learning process, particularly in a cooperative manner. Several UMR faculty have operated course-based learning centers (LCs) as part of the campus-wide Learning Enhancement Across Disciplines (LEAD) Program of student learning assistance and enhancement. LCs are designed to assist large numbers of students in a cost- and time-efficient manner that promotes student engagement without requiring undue amounts of faculty time. Course instructors spend time in the open learning environment of the LC, in lieu of office hours, guiding students to master course material and skills in their evolution from novice to …

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A Product Architecture-Based Conceptual Dfa Technique, Robert B. Stone, Daniel A. Mcadams, Varghese J. Kayyalethekkel Jan 2003

A Product Architecture-Based Conceptual Dfa Technique, Robert B. Stone, Daniel A. Mcadams, Varghese J. Kayyalethekkel

Mechanical and Aerospace Engineering Faculty Research & Creative Works

A conceptual design for assembly (DFA) method is introduced in this paper. The method incorporates DFA analysis into the conceptual design phase. Current DFA methods, essentially all of which are post-design DFA analyses, are reviewed with emphasis on the popular Boothroyd and Dewhurst method. The product architecture-based conceptual DFA method developed and presented in this article uses two relatively new concepts: the functional basis and the method of module heuristics. The functional basis is used to derive a functional model of a product in a standard language and the module heuristics are applied to the functional model to identify a …

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Modeling Fracture In Laminated Automotive Glazing Impacted By Spherical Featureless Headform, Lokeswarappa R. Dharani, S. R. Mettu, S. Zhao, S. D. Barbat, L. Chai Jan 2003

Modeling Fracture In Laminated Automotive Glazing Impacted By Spherical Featureless Headform, Lokeswarappa R. Dharani, S. R. Mettu, S. Zhao, S. D. Barbat, L. Chai

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Laminated glass consisting of two soda lime glass plies adhered by a polyvinyl butyral interlayer (PVB) is used for automotive glazing. This paper describes the application of a dynamic, nonlinear finite element method to investigate the failure modes of a laminated glass subjected to low-velocity impact with a spherical head form. Crack type, crack location and crack initiation time are evaluated using the maximum principal stress and J-integral criterion. Failure occurred due to flexural stresses and not bearing stresses. the first crack always initiated at the center of the outer impacted ply and PVB interface, and later on the exterior …

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Multidimensional, Time-Accurate Cfd Simulation Of Adsorption/Desorption In A Carbon Canister, Xingyan Bai, Kakkattukuzhy M. Isaac, D. Klein, R. Banerjee, J. Edson, W. Breig, L. Oliver Jan 2003

Multidimensional, Time-Accurate Cfd Simulation Of Adsorption/Desorption In A Carbon Canister, Xingyan Bai, Kakkattukuzhy M. Isaac, D. Klein, R. Banerjee, J. Edson, W. Breig, L. Oliver

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Computational fluid dynamics simulations of fixed-bed adiabatic adsorption/desorption processes are presented in this paper. Linear driving force model is used for heat and mass transfer rates. a two-dimensional cylindrical canister and three-dimensional automotive production canister geometry are used to study the adsorption/desorption processes of carbon dioxide in helium carrier gas on Norit B4 activated carbon. the two-dimensional results compare well with the results of Hwang et al. [1]. Computational results as breakthrough curve, adsorption amount and temperature profiles are provided. Results show that non-adiabatic model should be used to fully utilize the activated carbon bed capacity prior to breakthrough. Copyright …

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Experimental Studies Assessing The Repeatability Of A Functional Modeling Derivation Method, Mark A. Kurfman, Michael E. Stock, Robert B. Stone, Jagan Rajan, Kristin L. Wood Jan 2003

Experimental Studies Assessing The Repeatability Of A Functional Modeling Derivation Method, Mark A. Kurfman, Michael E. Stock, Robert B. Stone, Jagan Rajan, Kristin L. Wood

Mechanical and Aerospace Engineering Faculty Research & Creative Works

This paper presents the results of research attempts to substantiate repeatability and uniqueness claims of a functional model derivation method following a hypothesis generation and testing procedure outlined in design research literature. Three experiments are constructed and carried out with a participant pool that possesses a range of engineering design skill levels. the experiments test the utility of a functional model derivation method to produce repeatable functional models for a given product among different designers. in addition to this, uniqueness of the functional models produced by the participants is examined. Results indicate the method enhances repeatability and leads designers toward …

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Mapping Function To Failure Mode During Component Development, Irem Y. Tumer, Robert B. Stone Jan 2003

Mapping Function To Failure Mode During Component Development, Irem Y. Tumer, Robert B. Stone

Mechanical and Aerospace Engineering Faculty Research & Creative Works

When designing aerospace systems, it is essential to provide crucial failure information for failure prevention. Failure modes and effect types of analyses and prior engineering knowledge and experience are commonly used to determine the potential modes of failures a product might encounter during its lifetime. When new products are being considered and designed, this knowledge and information is expanded upon to help designers extrapolate based on their similarity with existing products and the potential design tradeoffs. in this work, we aim to enhance this process by providing design-aid tools which derive similarities between functionality and failure modes. Specifically, this paper …

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Missile Longitudinal Autopilot Design Using A New Suboptimal Nonlinear Control Method, Ming Xin, S. N. Balakrishnan Jan 2003

Missile Longitudinal Autopilot Design Using A New Suboptimal Nonlinear Control Method, Ming Xin, S. N. Balakrishnan

Mechanical and Aerospace Engineering Faculty Research & Creative Works

A missile longitudinal autopilot is designed using a new nonlinear control synthesis technique called the θ-D approximation. The particular θ-D methodology used is referred to as the θ-D H2 design. The technique can achieve suboptimal closed-form solutions to a class of nonlinear optimal control problems in the sense that it solves the Hamilton-Jacobi-Bellman equation approximately by adding perturbations to the cost function. An interesting feature of this method is that the expansion terms in the expression for suboptimal control are nothing but solutions to the state-dependent Riccati equations associated with this class of problems. The θ-D H2 design has the …

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Proper Orthogonal Decomposition Based Modeling And Experimental Implementation Of A Neurocontroller For A Heat Diffusion System, Prashant Prabhat, S. N. Balakrishnan, Dwight C. Look, Radhakant Padhi Jan 2003

Proper Orthogonal Decomposition Based Modeling And Experimental Implementation Of A Neurocontroller For A Heat Diffusion System, Prashant Prabhat, S. N. Balakrishnan, Dwight C. Look, Radhakant Padhi

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Experimental implementation of a dual neural network based optimal controller for a heat diffusion system is presented. Using the technique of proper orthogonal decomposition (POD), a set of problem-oriented basis functions are designed taking the experimental data as snap shot solutions. Using these basis functions in Galerkin projection, a reduced-order analogous lumped parameter model of the distributed parameter system is developed. This model is then used in an analogous lumped parameter problem. A dual neural network structure called adaptive critics is used to obtain optimal neurocontrollers for this system. In this structure, one set of neural networks captures the relationship …

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Hierarchical Optimal Control Of A Turning Process - Linearization Approach, Anand Dasgupta, B. Pandurangan, Robert G. Landers, S. N. Balakrishnan Jan 2003

Hierarchical Optimal Control Of A Turning Process - Linearization Approach, Anand Dasgupta, B. Pandurangan, Robert G. Landers, S. N. Balakrishnan

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Machining process control technologies are currently not well integrated into machine tool controllers and, thus, servomechanism dynamics are often ignored when designing and implementing process controllers. In this paper, a hierarchical controller is developed that simultaneously regulates the servomechanism positions and cutting forces in a lathing operation. The force process and servomechanism system are separated into high and low levels, respectively, in the hierarchy. The high level goal is to maintain a constant cutting force to maximize productivity while not violating a spindle power constraint. This goal is systematically propagated to the lower level and combined with the low level …

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Output Feedback Force Control For A Parallel Turning Operation, Raghusimha Sudhakara, Robert G. Landers Jan 2003

Output Feedback Force Control For A Parallel Turning Operation, Raghusimha Sudhakara, Robert G. Landers

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Parallel machine tools (i.e., machine tools capable of cutting a part with multiple tools simultaneously but independently) are being utilized more and more to increase operation productivity, decrease setups, and reduce floor space. Process control is the utilization of real-time process sensor information to automatically adjust process parameters (e.g., feed, spindle speed) to increase operation productivity and quality. To date, however, these two technologies have not been combined. This paper describes the design of an output feedback controller for a parallel turning operation that accounts for the inherent nonlinearities in the force process. An analysis of the process equilibriums explains …

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Intelligent Strain Sensing On A Smart Composite Wing Using Extrinsic Fabry-Perot Interferometric Sensors And Neural Networks, Kakkattukuzhy M. Isaac, Donald C. Wunsch, Steve Eugene Watkins, Rohit Dua, V. M. Eller Jan 2003

Intelligent Strain Sensing On A Smart Composite Wing Using Extrinsic Fabry-Perot Interferometric Sensors And Neural Networks, Kakkattukuzhy M. Isaac, Donald C. Wunsch, Steve Eugene Watkins, Rohit Dua, V. M. Eller

Electrical and Computer Engineering Faculty Research & Creative Works

Strain prediction at various locations on a smart composite wing can provide useful information on its aerodynamic condition. The smart wing consisted of a glass/epoxy composite beam with three extrinsic Fabry-Perot interferometric (EFPI) sensors mounted at three different locations near the wing root. Strain acting on the three sensors at different air speeds and angles-of-attack were experimentally obtained in a closed circuit wind tunnel under normal conditions of operation. A function mapping the angle of attack and air speed to the strains on the three sensors was simulated using feedforward neural networks trained using a backpropagation training algorithm. This mapping …

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Application Of A Finite Element Model Update Technique To Detect Damage In A Beam Structure, Madhu Kumar Vattipulusu Jan 2003

Application Of A Finite Element Model Update Technique To Detect Damage In A Beam Structure, Madhu Kumar Vattipulusu

Masters Theses

"The interest in the ability to monitor a structure and detect damage at the earliest possible stage is pervasive throughout the civil, mechanical and aerospace engineering communities. The thesis focuses on the application of a finite element model updating technique to monitor and detect damage in beams. A Sensitivity Based Element-by- Element (SBEBE) methodology is chosen as the finite element model updating technique. In this method, damage is detected by updating a finite element model with test data obtained from "healthy" and "damaged" structures and observing the relative changes in the updated finite element models. The performance, efficiency and sensitivity …

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Mechanical Property Characterization Of Mouse Zona Pellucida, Yu Sun, Kai-Tak Wan, K. P. Roberts, J. C. Bischof, B. J. Nelson Jan 2003

Mechanical Property Characterization Of Mouse Zona Pellucida, Yu Sun, Kai-Tak Wan, K. P. Roberts, J. C. Bischof, B. J. Nelson

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Previous intracytoplasmic sperm injection (ICSI) studies have indicated significant variation in ICSI success rates among different species. In mouse ICSI, the zona pellucida (ZP) undergoes a "hardening" process at fertilization in order to prevent subsequent sperm from penetrating. There have been few studies investigating changes in the mechanical properties of mouse ZP post fertilization. To characterize mouse ZP mechanical properties and quantitate the mechanical property differences of the ZP before and after fertilization, a microelectromechanical systems-based multiaxis cellular force sensor has been developed. A microrobotic cell manipulation system employing the multiaxis cellular force sensor is used to conduct mouse ZP …

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Nonlinear H Infinity Missile Longitudinal Autopilot Design With Θ-D Method, Ming Xin, S. N. Balakrishnan Jan 2003

Nonlinear H Infinity Missile Longitudinal Autopilot Design With Θ-D Method, Ming Xin, S. N. Balakrishnan

Mechanical and Aerospace Engineering Faculty Research & Creative Works

In this paper, a new nonlinear control synthesis technique, the theta- D method, is employed to design a missile longitudinal autopilot. The θ-D technique yields suboptimal solutions to nonlinear optimal control problems in the sense that it provides approximate solution to the Hamilton-Jacobi-Bellman (HJB) equation. Semi-global asymptotic stability can be achieved by manipulating the perturbation terms which are added to the cost function in developing a series solution. Furthermore, this method can be used to provide an approximate closed-form solution to the state dependent Riccati equation. The particular θ-D methodology adopted in this paper is referred to as θ-D H …

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Photoreflectance Spectroscopy Of Strained (In)Gaasn/Gaas Multiple Quantum Wells, J. B. Heroux, Xiaodong Yang, W. I. Wang Oct 2002

Photoreflectance Spectroscopy Of Strained (In)Gaasn/Gaas Multiple Quantum Wells, J. B. Heroux, Xiaodong Yang, W. I. Wang

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The effect of a variation of the indium and nitrogen concentrations in Inᵪ Ga1-x As1-y Ny /GaAs multiquantum wells grown by molecular beam epitaxy is studied systematically by room temperature photoreflectance spectroscopy. The band gap redshift caused by a nitrogen fraction of 1.5% decreases by as much as 30% as the indium fraction increases from 0% to 20%. A moderate increase of electron effective mass (Δmₑ ~ 0.03m₀) is found in all samples containing nitrogen (y ≳ 1%). In compressively strained quantum wells, the energy separation between the first confined heavy and light hole energy levels decreases …

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Composite Structures Using Asphalt Based Roofing Scrap Materials: Eiera -- Final Report, V. J. Flanigan, K. Chandrashekhara, Susan L. Murray Sep 2002

Composite Structures Using Asphalt Based Roofing Scrap Materials: Eiera -- Final Report, V. J. Flanigan, K. Chandrashekhara, Susan L. Murray

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The uses of recycled materials in composites provide the potential for large cost savings and a solution to the ever-growing disposal problem. Shingles contain petroleum based binders and fillers, which used as a valuable resource in composite production. Composites offer inherent advantages over traditional materials in regard to corrosion resistance, design flexibility and extended service life. Use of scrap-roofing shingles as a core material in glass fiber reinforced composite materials offer potential low cost composite products such as sound barrier system, railroad ties and other building materials including blocks. In the present work, processes have been developed for shredding scrap …

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Laser Aided Part Repair -- A Review, Jinglei Wang, Sashikanth Prakash, Yashodhan Joshi, Frank W. Liou Aug 2002

Laser Aided Part Repair -- A Review, Jinglei Wang, Sashikanth Prakash, Yashodhan Joshi, Frank W. Liou

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Laser aided part-repair is an emerging trend that has great potential for future industrial applications. Part-repair technologies are currently used in repairing military and civilian equipment. The focus of this paper is to review the current repair processes, which use the laser-aided metal deposition technology. Many metal parts, which are worn by continual use, can be restored to working condition by the deposition of metal with a laser and machining. This not only extends the life of the part, but also, saves on cost. A comparison between various processes, their parameters, efficiency, cost, and etc. are also presented. The process …

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Object-Oriented Modeling And Fauly Detection Of A Powder Feeder For A Laser Metal Deposition System, Robert G. Landers, Michael Gene Hilgers, Frank W. Liou, Bruce M. Mcmillin Aug 2002

Object-Oriented Modeling And Fauly Detection Of A Powder Feeder For A Laser Metal Deposition System, Robert G. Landers, Michael Gene Hilgers, Frank W. Liou, Bruce M. Mcmillin

Mechanical and Aerospace Engineering Faculty Research & Creative Works

One of the most critical components of a laser metal deposition system is the powder feeder unit. Techniques are required to efficiently design and analyze these systems and to ensure fault tolerance during the operation. In this paper, a model of the powder feeder unit, based on object- oriented abstractions of it components, is developed. This model is modular in that specific components can be efficiently updated or replaced with components that perform a similar function. In addition, the model can be used for simulation allowing for efficient design and analysis. Assurance of the correctness of the powder feeder system …

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System Integration And Real-Time Control Architecture Of A Laser Aided Manufacturing Process, Mallikharjuna R. Boddu, Robert G. Landers, Srinivas Musti, Sanjeev Agarwal, Jianzhong Ruan, Frank W. Liou Aug 2002

System Integration And Real-Time Control Architecture Of A Laser Aided Manufacturing Process, Mallikharjuna R. Boddu, Robert G. Landers, Srinivas Musti, Sanjeev Agarwal, Jianzhong Ruan, Frank W. Liou

Mechanical and Aerospace Engineering Faculty Research & Creative Works

This paper discusses a hybrid deposition–removal manufacturing system being developed at the University of Missouri--Rolla. The system consists of a laser system, five-axis CNC machining center, and powder feeder system. A description of the control software, real-time control architecture, and integration of various subsystems to build the hybrid system is given. The interaction of the real-time controller with various sensors and subsystems to monitor and regulate the process is presented. The communication between integrated process planning for the system and real–time control is also discussed in this paper.

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Investigation Of Part Accuracy And Surface Roughness In Rapid Freeze Prototyping Based Investment Casting, Qingbin Liu, Ming-Chuan Leu, Stephen M. Schmitt Aug 2002

Investigation Of Part Accuracy And Surface Roughness In Rapid Freeze Prototyping Based Investment Casting, Qingbin Liu, Ming-Chuan Leu, Stephen M. Schmitt

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The study as described in this paper is aimed at investigating the dimensional accuracy and surface finish of metal parts made by investment casting with ice patterns generated by rapid freeze prototyping. The process of investment casting with ice patterns is described and contrast with conventional investment casting with wax patterns is made. The selection of binder material for ceramic slurries and the need for an interface agent to separate the ice pattern from the ceramic slurry in the mold making process are discussed. The accuracy and surface finish of ice patterns and of the metal castings are presented and …

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A Study On Effects Of Process Parameters In Rapid Freeze Prototyping, Frances D. Bryant, Guanghua Sui, Ming-Chuan Leu Aug 2002

A Study On Effects Of Process Parameters In Rapid Freeze Prototyping, Frances D. Bryant, Guanghua Sui, Ming-Chuan Leu

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Rapid Freeze Prototyping (RFP) is a relatively new solid freeform fabrication process, which builds a three-dimensional part according to a CAD model by depositing and freezing water droplets layer by layer. A study on the effects of RFP process parameters including the nozzle scanning speed, droplet size, and droplet frequency in building ice parts with a single-nozzle work head is made. Presented in this paper are the results of this study which indicate that these process parameters determine the ice layer thickness and ice line width, which in turn determine the surface roughness and the waiting time required after depositing …

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