bluuebunny/crossref_metadata_2025 huggingface dataset:
RoboCamp — Using Robotics to Teach Math, Science, and Engineering Principles
Authors: Vandergriff Katie U. , Cain Linda C.
Published: December 2021

RoboCamp provides an innovative experience in the area of robotics for educators. This fun, hands-on experience strengthens the teachers’ knowledge and skills in science, mathematics, engineering, and telecommunications and prepares them to effectively transfer the experience to students in the classroom.

RoboCamp is supported with a grant from the Tennessee State Department of Education and is a collaborative effort involving the Oak Ridge National Laboratory (ORNL), area school systems, industry supporting robotics, and the Universities of Tennessee and Memphis.

RoboCamp is held on-site at the ORNL and gives the teachers firsthand look at research in action. The teachers work side-by-side with scientists and engineers on robotics-related topics. These topics include the following:

• history and future of robotics;

• science, mathematics, and engineering as they relate to robotics;

• national standards and state and local curriculum frameworks;

• classroom implementation of robotics education utilizing national standards;

• current thinking on pedagogy and assessment; and

• fun, innovative ways to answer the age-old question, “But how do we use it in real life!?!”

RoboCamp participants tour a variety of sites that use robots. These tours include production plants, research facilities, and public schools involved in robotics education. Participants build several kinds of robots based on different operating principles, use computers and the Internet for robotics-related research, and work on a design problem using robotic solutions. Finally, participants work in teams to develop plans to transfer the experience to their schools.

Approximately twenty teachers are selected for participation in RoboCamp. Participants apply, and are selected, as members of a school team. A team is comprised of 3–5 members and may include teachers of the same grade or educators teaching different grades but within a school; teams are encouraged to include administrators and guidance counselors. Participants are paid a stipend and expenses. Teams are solicited statewide.
Design of a Multi-Finger Haptic Interface for Teleoperational Grasping
Authors: Springer Scott L. , Ferrier Nicola J.
Published: December 2021

In this paper the design of a multi-finger force-reflecting haptic interface device for teleoperational grasping is introduced. The haptic interface or “master” controller device is worn on the human operator’s hand and measured human finger positions are used to control the finger positions of a remote grasping manipulator or “slave” device. The slave may be a physical robotic grasping manipulator, or a computer generated representation of a human hand such as used in virtual reality applications. The forces measured by the robotic slave, or calculated for the virtual slave, are presented to the operator’s fingertips through the master providing a means for deeper human sensation of presence and better control of grasping tasks in the slave environments. Design parameters and performance measures for haptic interfaces for teleoperation are discussed. One key performance issue involving the high-speed display of forces during initial contact, especially when interacting with rigid surfaces, is addressed by the present design, reducing slave controller computation requirements and overcoming actuator response time constraints.

The design presented utilizes a planar four-bar linkage for each finger, to represent each finger bend motion as a single degree of freedom, and to provide a finger bend resistance force that is substantially perpendicular to the distal finger pad throughout the full 180 degrees of finger bend motion represented. The finger linkage design, in combination with a remote position measurement and force display assembly, provides a very light weight and low inertia system with a large workspace. The concept of a replicated finger is introduced which, in combination with a decoupled actuator and feed forward control, provides improved performance in transparent free motion, and rapid, stable touch sensation of initial contact with rigid surfaces. A distributed computation architecture with a PC based haptic interface controller and associated control algorithms are also discussed.
Failure Analysis and Design Improvement Considerations of Wood Screw Conveyors
Authors: Murphy Michael J.
Published: December 2021

Screw conveyors are a well know and well recognized means of moving material from one point to another. The wood products industry uses screw conveyors in the transportation of their raw materials throughout the mills. These screw conveyors are typically categorized by the common name of “wood screws”. Failures of wood screws are usually related to the imposed operating loads. Many wood screws are subjected to abnormally high loads that are sometimes not anticipated in the original design. Wood screws are also subjected to the effects of fatigue due to rotation. An unconventional new wood screw design was used at one location to address a condition of reoccurring failures and increase the reliability of the mill’s feeder system. This new design deviated from the popular method of fabricating the screw from one continuous piece of seamless pipe. Instead the new screw was fabricated by welding together pipe of two different wall thicknesses. The new screw design used one piece of thicker wall thickness pipe in the center one-third section and used two pieces of the original wall thickness pipe at each end. This design modification increased the section modulus and decreased the deflection of the screw at the center, but did not alter the existing drive and support arrangement of the screw. The welds between the different wall thickness sections of pipe were located at the quarter points which are away from the highly stressed areas of the center section of the screw.
Modeling and Optimization of Nozzle Design in Planar Flow Melt Spinning
Authors: Chen J. S.-J. , Tseng A. A.
Published: December 2021

Numerical and experimental studies were performed to analyze a planar flow melt spinning process (PFMS) with a focus on the optimal nozzle design. Three-dimensional computational fluid dynamics (CFD) modeling using FIDAP was carried out to analyze the flow distribution in various nozzle shapes including rectangular, trapezoidal, and hemispherical edges. A laser-based Particle Image Velocimetry (PIV) system was developed to measure the velocity field at the nozzle exit. The CFD modeling results were validated by the PIV measurements. It was found that a converging nozzle with diverging edges along with a 30°-injection angle provided the best design. The optimized nozzle was used to produce high quality ribbons as characterized by the surface roughness measurements and micrograph techniques.
Study of Metamodeling Techniques and Their Applications in Engineering Design
Authors: Wang Nanxin , Ge Ping
Published: December 2021

Physics based or mechanistic simulation models are frequently used in current engineering design to generate, evaluate and validate designs in order to shorten the design cycle time and reduce the cost. It often involves solving a set of none linear partial differential equations, which usually requires a lot of computing time to search for a solution. It can not satisfy the need to explore more design alternatives in the early design stage. Metamodeling is an active academic field and is attracting increased attention from the industry. Surrogate models built with the metamodeling techniques provide faster analysis alternatives to the mechanistic models. Using these surrogate models in the early design stage allows engineers to explore more design alternatives with less development time and therefore has the potential to enable better engineering decision to produce quality products for reduced cost. In this paper, we review the existing metamodeling techniques including design of experiments, response surface methodologies, machine learning, and kriging. The paper also documents the results of the performance evaluation of several different metamodeling tools using a vehicle greenhouse example.
Conceptual Process Planning: A Definition and Functional Decomposition
Authors: Feng Shaw C. , Zhang Y.
Published: December 2021

Conceptual process planning is an activity for designers to evaluate manufacturability and the manufacturing cost in the early design stage for mechanical parts production. Since major manufacturing costs of a product are committed in product specification and design, it is critical to be able to assess manufacturability and cost as early as possible in the design process. At the National Institute of Standards and Technology, the Design and Process Planning Integration (DPPI) project addresses the need for improving communication between conceptual design and conceptual process planning activities. Documenting the DPPI foundation, this paper provides a definition of conceptual process planning and describes its functions in an activity model. Also, this paper describes the conceptual process planning prototype system that has been implemented and integrated with a conceptual design system. The prototype system validates the definition, the activity model, and the integration between process planning and design in the early product development stage.
Graph-Based Setup Planning and Tolerance Decomposition for Computer-Aided Fixture Design
Authors: Zhang Y. , Hu W. , Rong Y. , Yen David W.
Published: December 2021

To bridge the gap between computer-aided process planning and computer-aided fixture design, an automated setup planning and tolerance decomposition method is developed in this research. Directed graph is extended to represent feature/ dimension/tolerance relationships (FTG) and datum/machining feature relationships (DMG). According to different production schemes and manufacturing resource capabilities, setup planning principles and algorithms are explored to automatically extract DMG from FTG. Under the true positioning frame (ANSI Y14.5), tolerance decomposition models are concluded to partition a tolerance into interoperable machining errors, such as locating error, tool alignment error, random process error. The setup plan with allowable locating tolerance specifications is the basis for fixture design. The proposed method is verified in a genuine manufacturing enterprise.
Determining Keyhole Stability for Plasma Arc Welding Process Control
Authors: Zhang Shaobin , Zhang YuMing
Published: December 2021

Stability of the keyhole plays a fundamental role in producing quality welds in keyhole plasma arc welding. Currently, keyhole size is assumed to be a measurement of its stability. To verify this idea, keyhole and weld pool were simultaneously imaged from the opposite side of the welding torch. Experimental results revealed that the width of the keyhole was not correlative with the stability of the keyhole: as long as the keyhole mode was maintained, the width remained constant despite the changes in the welding current and speed. However, it can be used to estimate the lower limit of the pool width for preventing keyhole collapse. Also, the upper limit of the pool width for preventing burn-through is approximately fixed for given applications. Hence, in this study, pool width, its upper limit, and keyhole width were used to determine the margins of the process from collapse and burn-through. To measure the state of the stability of the keyhole process, the stability distance and stability factor were proposed. Based on the imaging system used, the state of the stability can be monitored in real-time.
Virtual Rapid Prototyping Holography Basis
Authors: Wang Zhiyan , Guan Chengxiang
Published: December 2021

The so-called “virtual rapid prototyping” here is about a real 3D product modeling by holography. The basic work is to get large viewable angle and image depth hologram. A new method for recording rainbow hologram is proposed, multiple synthetic slits are created by displacing and multi-exposing an object, to expand hologram’s horizontal and vertical viewable angles, also the position of synthetic slit can be controlled to expand the image depth. There is no lens and real slit adopted for recording.
Hard Turning: Chip Formation Mechanisms and Metallurgical Aspects
Authors: Poulachon Gérard , Moisan Alphonse L.
Published: December 2021

A 100Cr6 (AISI E52100) steel in the hardness range of 180 to 750 HV10 was machined. Quick stop tests were carried out at various hardness values to observe the different chip formation mechanisms. A limit was found between the shearing and cracking chip formation. Experiments on the selected steel at 750 HV10 were carried out at various cutting speeds and feed rates. The “saw tooth chips” obtained were examined geometrically and metallurgically on longitudinal midsections. A relationship has been established between the chip geometry and the cutting conditions. A theoretical study of the chip shape was made, in particular its thickness. The friction stick slip velocities, and the segment apparition frequency were calculated. Each stage of the chip formation could be observed on each micrograph of Q.S.T, especially the crack initiation. A discussion on the apparition of the thin white layers is also proposed.
A Study of Cutting Forces for Milling Plain Carbon Steel Using Chamfered Main Cutting Edge Tools
Authors: Chang Chung-Shin
Published: December 2021

A new face milling model for tool geometries with a chamfered main cutting edge has been constructed. Theoretical values for cutting forces were calculated and compared to the experimental results with S45C medium carbon plate as the workpiece material. Force data from these tests were used to estimate the empirical constants of the mechanical model and to verify its prediction capabilities. A comparison of the predicted and measured forces shows good agreement Special tool holders were designed and manufactured to obtain various tool geometries, including chamfered main cutting edge, radial angle, axial angle and inclination angles. The tips were prepared to the required geometry using a tool grinder.
Cutting Fluid Aerosol Generation due to Spin-Off in Turning Operation: Analysis for Environmentally Conscious Machining
Authors: Chen Zhong , Wong Kinwah , Li Wei , Stephenson David A. , Liang Steven Y.
Published: December 2021

This paper presents an analytical model for the prediction of shop floor aerosol concentration and size distribution due to the spinoff of cutting fluid from a rotational workpiece in a turning operation. Based on atomization theory and principles of fluid motion, the model analyzes the generation of cutting fluid aerosol associated with the rotary disk and liquid sheet formations on the workpiece surface. In coupling with fluid flow rate analysis and Rosin and Rammler distribution model, the airborne particulate concentration and size distribution are expressed in terms of fluid properties, fluid application conditions, and machining process parameters. Experiments were performed with the use of light scattering particle measurement device to calibrate and verify the analytical models. Under various fluid flow rates and workpiece rotational speeds, experimental data have shown reasonable agreement with model predictions. The predictive models developed in this paper can be used as a basis for human exposure and health hazard analysis. It can also facilitate the control and optimization of the use of cutting fluids in achieving a balanced consideration of process productivity and environmental consciousness.
An Orthogonal Cutting Model Based on Finite Deformation Analysis: Part II — Constitutive Equations and Experimental Verification
Authors: Zheng Y. , Sutherland J. W.
Published: December 2021

In Part I of this paper, a model based on finite deformation analysis was developed to predict the forces in an orthogonal cutting operation. In the second part of the paper, the constitutive equations for O1 and L6 tool steels are developed using Hopkinson bar tests. A total of 90 statistically designed orthogonal cutting tests are conducted to investigate the cutting mechanics of O1 and L6 tool steels. Then the cutting model developed in Part I of this paper is applied to simulate all the 90 cutting tests using the measured material constitutive equations. All the measurable model outputs are calculated and compared with the corresponding cutting experiment results. The comparisons show that the cutting model based on finite deformation analysis can be successfully applied to predict the cutting forces, shear angle, and various relationships in machining (orthogonal cutting) tests.
Effects of Cutting Parameters on Chip Side-Curl Mechanisms and Variable Tool-Chip Contact in Turning
Authors: Balaji A. K. , Jawahir I. S.
Published: December 2021

This paper presents the results of an investigative study on the chip side-curling mechanism and the associated variable tool-chip contact in turning operations. The effect of various cutting and tool geometry parameters such as depth of cut-nose radius ratio, feed, inclination angle, etc. on chip side-curling are established in a hierarchical manner. The importance of variable friction at the tool-chip interface along the developed length of the cutting edge is shown from the experimental observations of the tool-chip contact area using a SEM analysis. The significant influence of the radial cutting force component on the resultant chip side-curl is established using a high speed-filming analysis of comparative experiments in tube and bar turning operations.
Implementation of the Latest Breakthrough in the Physics of Materials in Metal Cutting: Analysis and Preliminary Results
Authors: Astakhov Viktor P. , Komarovskiy A. A.
Published: December 2021

Everyday practice of cutting process planning requires reliable cutting force estimates, which currently can be obtained only from process-dependent machinability databases. The greatest obstacle to developing a more basic, efficient approach is a lack of understanding of material behavior under unique deformation conditions of cutting. The metal cutting process has been defined by the authors earlier as the purposeful fracture of workpiece material and, therefore, a new way to minimize the energy consumption per unit volume of the layer to be removed in cutting should be revealed in order to predict metal cutting performance. Unfortunately, the traditional mechanical metallurgy has too little to be used for such a purpose. This paper deals with practical applications of the equation of state of a solid to the metal cutting process. It is shown theoretically and proven experimentally that the energy consumed in cutting can be effectively controlled by applying external force fields to the workpiece.
High Speed Grinding of Silicon Nitride With Electroplated Diamond Wheels: II — Wheel Topography and Grinding Mechanisms
Authors: Hwang T. W. , Evans C. J. , Malkin S.
Published: December 2021

This is the second in a series of two papers concerned with high speed grinding of silicon nitride with electroplated diamond wheels. In the first paper (Hwang et al., in press), it was shown that grinding of silicon nitride is accompanied by dulling of the abrasive grains and a significant increase in the grinding forces and power. High wheel speed caused more wheel wear, which was attributed to a longer accumulated sliding length between the abrasive grains and the workpiece. This second paper is concerned with the progressive change in wheel topography during grinding and how it affects the grinding process. A statistical model is developed to characterize the wheel topography during grinding in terms of active cutting grains and wear flat area. According to this model, continued grinding is accompanied by an increase in both the number of active grains and the wear flat area on the wheel surface as the wheel wears down. The measured increase in grinding forces and power was found to be proportional to the wear flat area, which implies a constant average contact pressure and friction coefficient between the wear flats and the workpiece. Increasing the wheel speed from 85 m/s to 149 m/s significantly reduced the contact pressure, which may be attributed to a reduction of the interference angle, but had almost no effect on the attritious wear rate of the diamond abrasive. Therefore, more rapid wear of the diamond wheel at higher wheel speeds due to a longer sliding length may be offset by reduced contact pressures and lower grinding forces.
Specific Grinding Energy Causing Thermal Damage in Precision Gear Steels
Authors: Mayer John E. , Price Angie H. , Purushothaman Ganesh K. , Gopalakrishnan Sanjay V.
Published: December 2021

Thermal damage (burn) in carburized and hardened precision gear steels caused by grinding was investigated. Excessive grinding temperatures cause grinding bum and result in excessive scrappage. AISI 9310 and X53 gear steels, used in helicopters and tilt-rotor aircraft, respectively, were prepared and heat-treated by a production partner. Grinding tests were conducted on these steels. Nital etching was used to detect grinding burn. Models were established to predict onset of thermal damage for AISI 9310 and X53 steels based on specific grinding energy determined from grinding force measurements. The models were compared to results published for other steels.
Investigation of the Self-Dressing of Resin Bound Grinding Wheels
Authors: Miller Michele H. , Kakumanu Thrinath S.
Published: December 2021

Wheel self-dressing, a byproduct of wheel wear, is often desirable for maintaining consistent wheel performance. We investigated the self-dressing process by monitoring the cutting force in plunge grinding experiments and by developing a computer model to predict the cutting force as it changes with wheel wear. The experiments show the significant effect of infeed and work material on the evolution of the cutting force. The simulation predicts the effects of infeed, work material strength, and binder strength on the cutting force. In addition, we discuss ways to improve the model and its potential for aiding in the selection of wheel parameters.
Study on Acoustic Emission in the Grinding Process Automation
Authors: Chen Ming , Xue Bing-Yuan
Published: December 2021

Comprehensive experiments have been conducted to investigate the monitoring technique for grinding process automation with acoustic emission (AE) signal. The AE signal generated during the grinding process is analyzed to determine its sensitivity to process. The detection of contact between the grinding wheel and workpiece and in-process prediction of grinding burn have been discussed in sequence. The results have been obtained as follows: (1) AE contact detector can save the non-machine time remarkably, thus high efficiency is available. (2) An effective intelligent sensing system has been developed and grinding burn can predicted. As mentioned above, AE technique has found wide applications in the grinding process automation.
Cost Drivers in Sand Casting Design
Authors: Stoll Henry W.
Published: December 2021

Sand casting offers weight and cost advantages that make it an optimal manufacturing process choice for many situations. However, to fully realize the cost reduction potential of sand casting, the casting designer must specify geometry that is carefully chosen to minimize tooling complexity and lead time and to maximize process yield. This paper systematically explores the sources of cost in sand casting to understand how design decisions impact total cost. A comprehensive cost model for sand casting is proposed, several key design related cost drivers are identified, and the qualitative relationship between the cost drivers and cost sources is discussed.
Collaboration Technologies for Global Manufacturing
Authors: Steves Michelle P. , Knutilla Amy J.
Published: December 2021

One impact of the globalization of manufacturing is the growing requirement for teams that are not co-located to collaborate using shared information. In this paper, we present our approach to instituting and assessing collaboration technologies for manufacturing applications. We provide a brief overview of Computer Supported Cooperative Work (CSCW) and groupware and discuss some potential uses in manufacturing. We describe related research at NIST, focusing on a process engineering collaboration scenario. We also present two approaches to collaboration technology deployment, seeding and accelerated deployment, aimed at reducing deployment costs in the manufacturing environment. Ultimately, the work presented here, in addition to similar systematic deployment and assessment of collaboration tools in other manufacturing scenarios, will provide knowledge that is useful for manufacturers who wish to efficiently deploy and effectively use collaboration technologies.
Modeling and Verification of Interelectrode Gap in Electrochemical Machining With Passivating Electrolyte
Authors: Zhu D. , Rajurkar K. P.
Published: December 2021

The industrial applications of Electrochemical Machining (ECM) technology are limited due to difficulties in tool design, monitoring and control, and sludge generation and disposal. An accurate modeling and prediction of interelectrde gap (i.e. the gap between tool electrode and workpiece electrode) is one of the most important steps to minimize these difficulties. The interelectrode gap distribution depends on electric field distribution which is a function of many process parameters varying in space and time during electrochemical dissolution process. This paper proposes a model and numerical approach to determine the gap distribution. The model is based on determining the electric field in the interelectrode gap and finding a cathode (tool) boundary which will satisfy the Laplace Equation for potential distribution and all other boundary conditions to achieve the desired workpiece shape. The proposed method incorporates the variation of electrochemical machinability and, hence, is applicable to ECM with both non-passivating and passivating electrolytes. The proposed method does not require iterative redesign process, therefore, it provides excellent convergence and computing accuracy. The verification experiments have been conducted using a specially developed electrolytic cell and an industrial scale ECM system. A close agreement has been observed between theoretical and experimental results.
Piezo Actuator Hybrid Modeling for Nonlinear Inverse Control in Diamond Turning
Authors: Song Dongwoo , Li C. James
Published: December 2021

This paper describes a micro-positioning system based on piezo actuators and a spring mechanism, and a hybrid hysteresis model integrating a neural network and Preisach model to identify the inverse dynamics of the micro-positioning system. To improve the workpiece form accuracy in diamond turning, feedforward control using the hybrid inverse model and feedback PID control were applied individually and in combination. The performance of these controllers are compared in actual cutting tests.
Design of Laser Ultrasonic System for In-Process Weld Penetration Monitoring and Control
Authors: Hopko Sandra N. , Ume I. Charles , Erdahl Dathan S.
Published: December 2021

Ultrasonics is a widely used nondestructive testing technique, which is often applied off-line for weld quality inspection. Laser ultrasonic (LU) inspection systems have the potential for on-line application, providing the means to identify unacceptable welds as they are formed. Because LU systems are non-contacting, they can be used for testing moving specimens or for operation in hazardous and/or high temperature environments. A highly versatile system can be created when an optical fiber delivery system is incorporated into the design. Introduction of a focusing objective increases the allowable working distance and permits stronger generation using material ablation as the generating mechanism. This paper describes the development of a laser ultrasonic probe using an optical fiber delivery system with a distal end, focusing objective. The optical fiber delivery system can be configured as a single fiber source, a linear array (fiber bundle) or a phased array. Results include experimentally obtained directivity patterns demonstrating ultrasonic generation using ablation sources. Thermoelastic source results are also included. This paper demonstrates the potential of the fiber tool and presents an overview of the weld control scheme.
Predictive Modeling of Nonlinear Regenerative Chatter via Measurement, Analysis, and Simulation
Authors: Pratt J. R. , Davies M. A. , Kennedy M. D. , Kalmár-Nagy T.
Published: December 2021

A single-degree-of-freedom active cutting fixture is employed to reveal and analyse the hysteretic nature of the lobed stability boundary in a simple machining experiment. Specifically, the seventh stability lobe of a regenerative cutting process is mapped using experimental, analytical, and computational techniques. Then, taking width of cut as a control parameter, the transition from stable cutting to chatter is observed experimentally. The cutting stability is found to possess a substantial hysteresis so that either stable or chattering tool motions can exist at the same nominal cutting parameters, depending on initial conditions. This behavior is predicted by applying nonlinear regenerative chatter theory to an empirical characterization of the cutting force dependence on chip thickness. Time-domain simulations that incorporate both the nonlinear cutting force dependence on chip thickness and the multiple-regenerative effect due to the tool leaving the cut are shown to agree both qualitatively and quantitatively with experiment.
A Control Strategy and Upper Bound Solution for Non-Flat Tool Open Die Forging Automation
Authors: Nye T. J.
Published: December 2021

The open die forging process can provide a number of benefits if its costs can be made competitive through automation. This paper describes a control strategy for automated open die forging forming sequence generation. An upper bound solution for forging with radiused tools is developed, along with a method for using this solution to estimate forming results, a necessary component of the control strategy. Model predictions are compared to physical experimental data using plasticine, and show good agreement.
Mechanical Properties and Cutting Performances of High Purity Polycrystalline cBN Compact
Authors: Uesaka Shinya , Sumiya Hitoshi
Published: December 2021

Mechanical properties and cutting performances of high purity polycrystalline cBN (PcBN) compacts synthesized by the direct conversion method from hexagonal BN under high pressure and high temperature have been investigated. The hardness and transverse rupture strength (TRS) of the compacts in the temperature range of 293 to 1473 K depend strongly on the cBN grain size and the amount of residual hBN in the compact. The fine-grained (< 0.5 μm) and high purity (> 99.9%) PcBN compacts synthesized at 7.7 GPa and about 2550 K. has the highest hardness and TRS at any temperature. All high purity PcBN compacts have high thermal conductivity above 300 W/m.K and show excellent thermal crack resistance in high speed wet cutting of gray cast iron and milling of steel, which are difficult for the conventional cutting tool materials. Especially, the fine-grained compact, which has high strength, exhibits excellent cutting performances.
Design Criteria for Hardturning Machines
Authors: Yasui Shouri , Sakai Kazutoshi
Published: December 2021

The benefits of hardturning include reduced setup costs; shorter tool change times; improved squareness by virtue of the ability to machine cylinder I.D., O.D. and face in one chucking; low energy consumption and elimination of the need to handle grinding sludge and waste fluid.

Hardturning has typically been used as a replacement for grinding, in the processing of fitting surfaces or clad surfaces, and other such relatively straightforward applications not requiring sliding. In recent years, however, due to advances in servo and other machine technology, and tool material improvements (CBN, ceramics), hardturning has entered the realm of finishing curved and complex shaped surfaces that have sliding and rolling contacts.

This paper will present the machine characteristics developed to meet the ever increasing demand for hardturning process accuracy, and introduce each of the factors which ultimately affected the design of machine components, providing examples where appropriate.
Experimental Investigation of Thermo-Mechanical Characteristics in Laser-Assisted Machining of Silicon Nitride Ceramics
Authors: Lei Shuting , Shin Yung C. , Incropera Frank P.
Published: December 2021

Laser-assisted machining (LAM) of silicon nitride (Si3N4) is evaluated for its potential to become an economically viable process in fabricating precision ceramic parts. On-line measurements of cutting force and workpiece temperature are performed, and tool wear and surface integrity are examined. Tool wear characteristics are determined as a function of workpiece temperature, which is measured on-line using a laser pyrometer. Tool wear/failure mechanisms are characterized using optical microscopy, while application of scanning electron microscopy to heated and machined surfaces, as well as to chips, is used to infer material removal mechanisms and the extent of damage caused by LAM. The sub-surface damage of parts produced by LAM is compared with that of typical ground parts.
A New Perspective of Residual Stress Induced by Machining and Grinding
Authors: Liu C. Richard , Yang Xiaoping
Published: December 2021

Residual stress is one of the most important factors affecting product surface integrity. Every machining operation produces a distinctive residual stress in the surface layer. The surface residual stress produced by grinding and face turning were measured in very small surface areas at several locations of each sample using X-Ray diffraction technique. Significant point-to-point residual stress variations were found in the ground surfaces, which poses a potential hazard to applications requiring high surface integrity. On the other hand, only small point-to-point residual stress variations were found in the face turned surface. An explanation to this phenomenon has been given. Residual stress on seven samples undergone multiple-pass grinding were also measured, the results of which show that final residual stress distribution on a ground workpiece depends on the initial residual stress, the number of grinding pass, as well as grinding conditions. It is suggested that single-point cutting be used in place of abrasive grinding.
Achieving Precision Grinding Quality by Hard Turning
Authors: Jochmann Sven , Wirtz Holger
Published: December 2021

In the past decade, the technology of finish machining hardened steels with geometrically defined cutting edges has been developed. Due to its high potential to increase productivity as well as competitiveness, research and development has focused on enlarging the use of hard turning for components with very high requirements on surface quality (Rz < 1 μm), form and shape tolerances (IT3 - IT5). In this paper, a detailed comparison on achievable workpiece quality for finish grinding with Al2O3- and CBN-wheels and finish hard turning is presented. It will be shown that finish hard turning is today capable of achieving and maintaining workpiece qualities within the same high range like finish grinding processes.
Evaluating Variation Reduction Process Control Strategies Through System Modeling
Authors: Suri Rajiv , Otto Kevin
Published: December 2021

This paper presents a method for using a system model to reduce end-of-line variation in a sheet stretch-forming manufacturing system. An integrated set of mathematical models representing the operations in a system can be effectively used to select among four variation reduction strategies: robust process design, input variation reduction, feed-forward control, and feedback control. To compare these alternatives, models that predict both quality characteristic nominal values and standard deviations of the work-in-process are required. Numerical simulation using these models allows for evaluation and comparison of each strategy prior to any activity on the shop floor. This approach is demonstrated on a sheet stretch-forming manufacturing system from the aerospace industry. A feed-forward strategy is selected as having the greatest potential for this system. A subsequent experimental validation on the shop floor showed a 30% reduction in strain variation on a batch of production parts.
Design and Analysis of a New High Performance Electrohydraulic Actuator
Authors: Habibi Saeid , Goldenberg Andrew
Published: December 2021

This paper describes a new high performance robotic actuation system that presents a powerful alternative to existing commercial systems. This actuation system is self-contained and combines the benefits of conventional hydraulic and direct drive electrical actuators, namely high torque/mass ratio and modularity. It is referred to as the ElectroHydraulic Actuator (EHA) and results from the fusion of the above mentioned technologies. EHA is a unique device with its own characteristics and requires hydraulic components that are specifically tailored to its needs. To fulfill these requirements, a new symmetrical Linear Actuator (SLA) was designed as a sub-component of EHA. Experimental data from a prototype of EHA are reported.
Design Methodology for Fluid Power Systems Using Hypermedia
Authors: Hughes Edmund J. , Richards Thomas G. , Tilley Derek G.
Published: December 2021

Fluid power system design is a skilful and complex task requiring significant practical experience and heuristic knowledge gained over many years. Industries specifying and/or designing fluid power systems in their products are at risk should they lose key personnel with this knowledge. This problem is compounded by a lack of formal training at the graduate level, creating a shortfall in qualified fluid power designers.

Design support tools that assist and guide designers in their work, as part of a Concurrent Engineering approach, should be capable of providing both good practice guidance and a framework into which product specific information can be stored for later reuse. This paper discusses the early development of a fluid power system design tool that seeks to offer this support using a methodology developed in hypermedia.
A Future Micro Hydro-Propulsive System
Authors: Bayandor Javid , Abanteriba Sylvester , Bates Ian
Published: December 2021

This paper discusses the development of production of a new type of hydro-propulsive system for the generation of the power. First, the principles which seek to quantitatively describe the behavior of this unconventional system are established. A brief description of the mechanical design is included. A parametric study of the major influences on the performance of the system has been carried out and discussed. Finally, the comparison of theoretical simulation and experimental is indicated and discussed in detail.
Two-Level Hierarchical Control of Hydraulic Elevator Speed
Authors: Ran Longlin , Yang Huayong
Published: December 2021

The speed control of hydraulic elevators is usually carried out by PID controllers. But as the system properties slowly changes with the working situation, the control result is not satisfactory after long time operation. In this paper, a two-level hierarchical controller consist of an intelligent PI controller and a simple upper level expert controller is introduced. The expert controller is based on the expert knowledge accumulated from research experiences on the speed control of hydraulic elevators. The controller is realized on a small chip computer system, which is cheap and flexible to use.
Motion Synchronization of Multiple Hydraulic Actuators: A Linear Multivariable Approach
Authors: Sun Hong , Chiu George T.-C.
Published: December 2021

The electro-hydraulic (EH) synchronized motion of two linear ram type hydraulic actuators is considered in this paper. It is shown that the combined system of the load and the hydraulic actuators is unstable and requires additional mechanical and/or electronic synchronization. Two EH synchronization control methods, multivariable pole placement (MPP) and Linear Quadratic Integration (LQI), are presented based on a linearized multivariable model. It is shown that the synchronization error can be penalized implicitly or explicitly using multivariable control designs. Simulation results demonstrated that decoupled control as well as flow divider techniques can not adequately address the motion synchronization issue. Both multivariable control approaches showed significant improvement compared with individual controlled cylinders.
Innovative Design of Manufacturing Systems
Authors: Tsourikov Val , Devoino Igor
Published: December 2021

This paper focuses on a knowledge-based approach to innovative design of manufacturing systems and processes. Innovative design includes three major steps: Functional Analysis of the manufacturing process; Innovative Concept Search in the semantic knowledge base of technical and scientific effects and New Concept selection using quantitative as well as qualitative data.
A Model for Conceptual Design Methodology
Authors: Condoor Sridhar S. , Weber Richard G.
Published: December 2021

Conceptual design is the seminal phase in the design process. This phase determines the level of product innovation, the efficiency of the product, and the effectiveness of the down-stream stages of the design process. It has tremendous leverage on the final product performance, cost, and time-to-market. To improve the efficiency of the conceptual design process, the paper combines the parameter analysis methodology with a fundamental insight from robust design. Parameter analysis is a generic design methodology that aids in systematically developing an idea into a viable design. It is particularly useful in creating innovative conceptual designs. Robust design is, often, used after finalizing the conceptual design. Robust design improves the product quality by first reducing the variability in product performance and then, tuning the low variability performance onto the target. The paper presents guidelines for executing the parameter analysis methodology which in turn provides consistent or low variability performance by considering robustness in the very early phases of the design process. The paper illustrates this process with two case studies. The case studies also show how to qualitatively optimize a conceptual design by developing the overall concept before details.
Concurrent Cost Calculations With a Feature-Based CAD System
Authors: Leibi Peter , Hoehne Guenther , Hundal Mahendra
Published: December 2021

The paper describes a procedure for calculating costs concurrent with the design process. The different modules of the computer program “IKF” are described. The modules include those for cost calculation, comparison and forecast. Form features are used for cost determination by classifying each feature and storing it in the detailed production plan. The production processes then follow from the list of stored features. The cost program takes the individual geometric data, e.g., part length, from the CAD program. The latter contains data sets, that describe the feature’s dimensions. The production time for the form feature is then calculated. From the time expenditures and the machine rates the program calculates the production costs for the given feature. Prior to developing the computer program a manual procedure was designed and developed. Upon testing, the group not using IKF took 40–50% more time and designed products that were about 80% costlier than the group using the IKF system. This procedure was then used as the model for the cost modules in a feature-based CAD program. Test cases dealing with sheet-metal design are described which demonstrate and quantify the advantages of this system.
Some Limitations of TRIZ Tools and Possible Ways of Improvement
Authors: Kosse V.
Published: December 2021

The Ideation/TRIZ Methodology has grown into the most powerful engineering problem solving methodology. However, experienced users may discover some limitations of TRIZ tolls, such as empty cells in the Contradiction Matrix, missing physical effects in the library of physical effects. In this paper possible ways of improvement of the Contradiction Matrix as well as special physical effects to complement the list of physical effects and phenomena are discussed.
An Analytical-Experimental Study for the Determination of the Effective Thermal Conductivity of High Porosity Fibrous Foams
Authors: Bhattacharya Anandaroop , Calmidi Varaprasad V. , Mahajan Roop L.
Published: December 2021

In this paper, we present a comprehensive analysis for estimating the effective thermal conductivity of high porosity fibrous foams. Commercially available fibrous foams form a complex array of interconnected fibers with an irregular lump of metal at the intersection of two fibers. In our theoretical analysis, we represent this structure by a model consisting of two-dimensional hexagonal arrays where the fibers form the sides of the hexagons. The lump is taken into account by considering a square, hexagonal or circular blob of metal at the intersection. The analysis shows that the effective thermal conductivity of the foam depends strongly on the porosity and the ratio of the cross-sections of the fiber and the intersection. It has no systematic dependence on pore density. Further, the choice of the geometric configuration of the intersection affects the estimate of the effective thermal conductivity. Experimental data with aluminum and Reticulated Vitreous Carbon (RVC) foams, using air and water as fluid media are used to validate the analytical predictions. Finally, the experimental results are used to arrive at a simple, closed-form empirical correlation for estimating the effective thermal conductivity in terms of the porosity, and the solid and fluid conductivities.
Solar Radiation Thruster Performance Analysis With Energy Storage in Porous Material
Authors: Chen Yen-Sen , Liu Jiwen , Wei Hong
Published: December 2021

The objective of this study is to develop analytical codes to support the design effort of the Shooting Star Flight Experiment’s rocket engine. Numerical models can augment the design effort by providing insight into fluid dynamics issues. Then, the design team can utilize the developed code to assess the design parameters and the engine performance as well as other issues related to thermal propulsion. The physical models developed in this study are: (a) a radiation model based on a GRASP code for general multi-block curvilinear coordinates and with a time accurate Crank-Nicholson marching scheme for heat conduction to model the absorber component of the engine; and (b) a fluid dynamics computational model using the Navier-Stokes equations, porosity factors and drag forces terms for simple one-dimensional simulations to complete three-dimensional modeling of the Shooting Star Engine internal flows.