bluuebunny/crossref_metadata_2025 huggingface dataset:
Design, Fabrication and Industrial Application of a Miniature Hovercraft
Authors: Gera Prerna , Sarkar Sayan , Jha Rameshwaranand , Raj Rishi , Bardhan Rishi , Vikas  , Gupta Siddharth
Published: July 2010

The difficult lives of workers in a manufacturing industry can be improved by the use of a simple ‘Hovercraft’. This vehicle runs on air from the pressure lines in any industry. Since there is zero resistance between the smooth surface and the craft, the effort to move very heavy bodies is reduced significantly. The craft with a specially designed skirting shape will allow it to lift the load placed on it with ease. There would be eddy formation and stability would need to be taken into account. Hovercraft has been designed before but its application in industries is of the level of innovation (atleast in India for the moment). Many shapes of the hovercraft can be used and experimented with, but we have mainly stuck to the rectangular one. This technology will be very cheap and will sort out a lot of problems in industries. It will save a chunk of the transportation money. Braking is a big problem in the design, but can be overcome by new types of brakes. As the load taken by the hovercraft is proportional to the size, space limitations also imply. So in all it will, as stated earlier, save time, money and energy of the workers.
Adhesive Density of 11-Mercaptoundecanoic Acid (MUA) and Turnip Yellow Mosaic Virus (TYMV) in Microfluidic Channels
Authors: Wu Chia-Che , Tseng Ping-Kuo , Hou Meng-Jhu , Tsai Ching-Hsiu
Published: July 2010

Recently, there has been an increasing interest to develop rapid, reliable and low-concentration detection methods of micro-organisms involved in bioterrorism, food poisoning, and clinical problems. How to detect virus at concentration below the threshold will be challenging with respect to specificity, selectivity, and sensitivity. Among all parameters, sensitivity is probably the most critical consideration. If the sensitivity is not satisfied for real-time detection, researchers need to duplicate numerous numbers of viruses. However, it will substantially increase processing times and experimental hazard. To increase the sensitivity of virus sensors, this paper discusses how to increase the density of linkers and viruses on sensor’s surface in the microfluidic channels. In the future, researcher could use emerging technology, such as PT-PCR, QCM, C-V and I-V measurements, etc, to detect viruses on sensor’s surface. Usually microorganisms, molecules, or viruses in the fluidic environment are at very low Reynolds numbers because of tiny diameters. At very low Reynolds numbers, viscous forces of molecules and viruses will dominate. Those micro- or nanoparticles will stop moving immediately when flows cease and drag forces disappear. Of course, molecules and viruses are still subject to Brownian motion and move randomly. In order to increase the adhesion density of micro- and nanoparticles on sensor’s surface, designs of the flow movements in microfluidic channel is proposed. Adhesion density of linker 11-mercaptoundecanoic acid (MUA) and turnip yellow mosaic virus (TYMV) with specific quantum dots were measured by confocal microscope. Results show that TYMV and MUA layers disperse randomly by dipping method. Infusion rate, flow rate, and transverse flow could affect the adhesion densities of recognition layers on sensors’ surface. Adhesion densities of MUA and TYMV can be reached 70∼80% by microfluidic method to contrast just 10% by dipping method.
Estimation of the Center of Mass Using Statically Equivalent Serial Chain Modeling
Authors: Cotton Sebastien , Murray Andrew , Fraisse Philippe
Published: July 2010

This paper proposes a new technique to estimate the center of mass (CoM) of mechanical systems defined by an articulated set of rigid bodies. This technique is based on the use of the statically equivalent serial chain, a serial chain representation on any multi-link branched chain. Through the use of this model, and without any knowledge of each individual body’s CoM or CoM location, a simple method to estimate the mechanical system’s CoM is developed. This method is validated with the CoM estimation of the Hoap-3 humanoid robot. A sensitivity calculation for estimating the CoM in this way is also presented.
Variation Analysis of Position, Velocity, and Acceleration of Two-Dimensional Mechanisms by the Direct Linearization Method
Authors: Leishman Robert C. , Chase Kenneth W.
Published: July 2010

Velocity and acceleration analysis is an important tool for predicting the motion of mechanisms. The results, however, may be inaccurate when applied to manufactured products, due to the process variations which occur in production. Small changes in dimensions can accumulate and propagate in an assembly, which may cause significant variation in critical kinematic performance parameters. A new statistical analysis tool is presented for predicting the effects of variation on mechanism kinematic performance. It is based on the Direct Linearization Method developed for static assemblies. The solution is closed form, and may be applied to 2-D, open or closed, multi-loop mechanisms, employing common kinematic joints. It is also shown how form, orientation, and position variations may be included in the analysis to analyze variations that occur in kinematic joints. Closed form solutions eliminate the need of generating a large set of random assemblies, and analyzing them one-by one, to determine the expected range of critical variables. Only two assemblies are analyzed to characterize the entire population. The first determines the performance of the mean, or average assembly, and the second estimates the range of variation about the mean. The system is computationally efficient and well suited for design iteration.
Sensitivity Analysis of Atomic Force Microscope Cantilever Made of Functionally Graded Materials
Authors: Rahaeifard M. , Kahrobaiyan M. H. , Ahmadian M. T.
Published: July 2010

The purpose of this paper is the enhancement of the AFM sensitivity through the selection of an optimized FGM micro cantilever beam. In this paper, resonant frequencies and sensitivities of first two modes of micro cantilever which is made of functionally graded materials are investigated and a relationship is developed to evaluate the sensitivity of FGM micro cantilever. Effect of volume fraction of materials and surface contact stiffness on the resonant frequencies and sensitivities are studied. The rectangular FGM beam is modeled by an Euler-Bernoulli beam theory. It is assumed that beam is made of a mixture of metal and ceramic with properties varying through the thickness following a simple power law of n. This variation is a function of the volume fraction of the beam material constituents. The interaction between AFM tip and surface is modeled by a linear spring which expresses the contact stiffness. Results show that, increasing the ceramic volume fraction increases the resonant frequencies of both modes 1 and 2. When contact stiffness is small, for both modes, as ceramic volume fraction increases, sensitivities decreases, while for large contact stiffness, as ceramic volume fraction increases the sensitivities will be increased. Results also show that at each contact stiffness, there is a unique value of n at which the sensitivity is maximized. Using these values for n, the high quality and high contrast images can be obtained.
Customer-Centric Product Modeling for Rapid Product Identification in One-of-a-Kind Production
Authors: Hong G. , Xue D. , Tu Y. L.
Published: July 2010

One-of-a-kind production (OKP) is a new manufacturing paradigm to produce customized products based on requirements of individual customers while maintaining the quality and efficiency of mass production. In this research, a customer-centric product modeling scheme is introduced to model OKP product families by incorporating the customer information. To develop this modeling scheme, data mining techniques, including fuzzy pattern clustering method, and hybrid attribute reduction method, are employed to achieve the knowledge from the historical data. Based on the achieved knowledge, the different patterns of OKP products are modeled by different sub-AND-OR trees trimmed from the original AND-OR tree. Since only partial product descriptions in a product family are used to identify the optimal custom product based on customer requirements, the efficiency of custom product identification process can be improved considerably. A case study to identify the optimal configuration and parameters of window products in an industrial company is used to demonstrate the effectiveness of the introduced approach.
Improvement of Bending Fatigue Strength for Hybrid Cords With Carbon and Glass Fibers
Authors: Furusawa Masamori , Tsukada Yuuya , Morimoto Takuya , Iizuka Hiroshi
Published: July 2010

Synchronous belts are rubber-composite materials with rubber, helical cords and facing fabrics. The helical cord is the tension member of the belt and is made of glass fibers, aramid fibers, or steel wires. Recent trends require increasingly high stiffness for the rubber belts. The use of carbon fibers and hybrid cords with carbon fibers are considered to be an effective way to achieve high stiffness for helical cords. This paper presents the study is to improve the bending fatigue strength of hybrid cords, where the center strand is made of carbon fibers, and the outer strands are made of glass fibers. The optimum cord composition for good bending fatigue durability is discussed following experimentation, mechanical analysis using a simplified mechanical model and FEM analysis. The model reasonably explained the initiation of the fatigue failure initiation site in the hybrid cords. The optimum cord composition was proposed for the bending fatigue strength basing on the simplified mechanical model. This was verified by experimental data showing good fatigue life. The use of such helical cords can considerably extend the operating life of synchronous belts.
Robust H-Infinity Control of an Over-Head Crane System With Parametric Uncertainties
Authors: Moradi Hamed , Haji Hajikolaei K. , Bakhtiari-Nejad Firooz
Published: July 2010

To achieve high positioning accuracy, short transportation time and small swing angle of an overhead crane system, both motion and stabilization control strategies are required. Under different loading condition, an over-head crane system may experience a range of parameter variation. Consequently, to enhance both efficiency and safety and to extend the system application to other engineering fields, a robust controller is required. In this paper, an over-head crane is modeled as a nonlinear two degrees of freedom system with parametric uncertainties. The force exerted on trolley is considered as the control input of the system. Applying an inversed-base controller based on μ-analysis, robust stability and nominal performance are achieved for the perturbed plants. Using μ-synthesis with DK-iteration algorithm, an optimal robust controller is designed which guarantees the robust performance too.
The Product Innovation Engineering Program: Promoting Creativity, Synthesis and International Collaboration
Authors: Grimheden Martin
Published: July 2010

The Product Innovation Engineering Program, PIEp, is a large, national research and development program aimed at performing a system change of innovation capabilities within Swedish industry and higher education. PIEp is a network of students, researchers and product developers and relies heavily on collaboration with international renowned networks, advisors and universities. This paper aims at introducing PIEp and the fields of PIEp active in engineering education on an international arena. The ambition is to strengthen existing networks and find new partners. One of the ambitions of this paper is further to promote the program with the purpose of finding future collaborative projects, within the context of product innovation engineering education. Also, current activities and results from the first years of operation are presented.
Generation of Under-Actuated Parallel Robots With Non-Holonomic Joints and Kinetostatic Analysis of a Case Study
Authors: Grosch Patrick , Di Gregorio Raffaele , Thomas Federico
Published: July 2010

It will be shown how to generate under-actuated manipulators by substituting non-holonomic spherical pairs (nS pairs) for (holonomic) spherical pairs (S pairs) in fully-parallel manipulators (FPMs). Through this pair substitution, an under-actuated manipulator, previously proposed by one of the authors, will be demonstrated to be generated from an inversion of the 6-3 FPM. Moreover, the kinetostatic analysis of this manipulator will be reconsidered to obtain a simple and compact formulation. This reformulated analysis can be used both in the design of the under-actuated manipulator, and in its control.
On the Design of a Vertical Axis Wind Turbine for Use in Rural Communities
Authors: Johnston Allison , French Jesse , Henshaw John
Published: July 2010

The paper describes the design specifications for a hand built wind turbine that is optimally used in regions such as North East China. The authors have developed a design for a home sized wind turbine. A region with some of the highest wind speeds in the world, North East Jilin is an ideal site for vertical axis wind power. Because of its ability to generate power best in high winds, a Darrieus-type turbine is the modified and tested design. Since it is low to the ground, it can be raised and lowered for maintenance and repair without need of expensive equipment or cranes. The design employs a direct drive shaft that can attach to a water pump, an air compressor, or a car alternator. In this way the owner of the turbine can pump water, compress air, or generate electricity depending on personal need. The turbine was designed considering probable implementation locations, and therefore all materials and fabrication techniques are easily accessible by the rural Chinese. The turbine was constructed and raised, and testing was begun.
Infinitesimal Kinematics Methods in the Mobility Determination of Kinematic Chains
Authors: Rico J. M. , Cervantes J. J. , Tadeo A. , Gallardo J. , Aguilera L. D. , Diez C. R.
Published: July 2010

In recent years, there has been a good deal of controversy about the application of infinitesimal kinematics to the mobility determination of kinematic chains. On the one hand, there has been several publications that promote the use of the velocity analysis, without any additional results, for the determination of the mobility of kinematic chains. On the other hand, the authors of this contribution have received several reviews of researchers who have the strong belief that no infinitesimal method can be used to correctly determine the mobility of kinematic chains. In this contributions, it is attempted to show that velocity analysis by itself can not correctly determine the mobility of kinematic chains. However, velocity and higher order analysis coupled with some recent results about the Lie algebra, se(3), of the Euclidean group, SE(3), can correctly determine the mobility of kinematic chains.
Modified Sky-Hook Control of a Semi-Active Suspension System Using H∞ Robust Control Theory
Authors: Fallah Mohammad Saber , Bhat Rama , Xie Wen-Fang
Published: July 2010

The main focus of the present paper is on the design of a modified sky-hook control of a semi-active Macpherson suspension system by means of H∞ Output Feedback Control (OFC) theory. To this end, a new dynamic model, incorporating the kinematics of the suspension system, is used for the controller design. The combination of a Linear Matrix Inequality (LMI) solver and Genetic Algorithm (GA) is adopted to regulate the static output feedback control gain so that the stability conditions are fulfilled and control objectives are achieved. Meanwhile, a three-dimensional kinematic model of the system is incorporated to investigate the influence of the control force variation on the steering, handling and stability of the vehicle. A geometric relation of the vehicle roll center is employed to study one more extra aspect of the comfort and stability of the vehicle. The results show that the proposed controller improves the kinematic and dynamic performances of the suspension well compared with those of the passive system. Moreover, it is concluded that a superior stability of the vehicle during the cornering can be achieved by adjusting the height of the vehicle roll center passively so that the stability of the vehicle is improved while the forward motion specifications can be modified by an appropriate suspension control design.
Closed-Form Equations of Mass Matrix of the Single-Axis Right Circular Flexure Hinge
Authors: Zhang Xianmin , Hou Wenfeng , Guan Yisheng
Published: July 2010

This paper presents a closed-form expression of the mass matrix of the right circular hinges which are widely used in compliant mechanism systems. The flexure hinge is treated as a two nodes element, in which there are three degrees of freedom at each node. The cosine functions with high-order terms are introduced, and the closed-form expression for each element of the mass matrix of the single-axis right circular flexure hinge is obtained. Based on the closed-form expression, the dynamic equations of motion of a piezodriven 3-DOF compliant precision micro-positioning stage are developed. The lower order modal frequencies are experimentally identified and the dynamic analysis model is proved to be feasible. Dynamic and static output comparisons show that the dynamic analysis is highly necessary for a precision micro-positioning stage. The closed-form expression of the mass matrix of the right circular hinge made it more convenient for dynamic analysis of the compliant mechanisms by using finite element approach.
A Structural Optimization Method for Universal Design of Compliant Mechanism Scissors
Authors: Izui Kazuhiro , Yokota Kiyoshi , Yamada Takayuki , Nishiwaki Shinji , Yoshimura Masataka
Published: July 2010

This paper proposes a structural optimization-based method for the design of compliant mechanism scissors in which the proposed design criteria are based on universal design principles. The first design criterion is the distance from the hand-grip to the center of gravity of the scissors, which should be minimized to reduce the physical effort required of the people using the device. The second design criterion is that of failure tolerance, where the effects of traction applied in undesirable directions upon the performance of the compliant mechanism should be minimized. Based on the proposed design criteria, a multiobjective optimization problem for the universal design of a compliant mechanism scissors is formulated. Furthermore, to obtain an optimal configuration, a new type of topology optimization technique using the level set function to represent structural boundaries is employed. This optimization technique enables rapid verification of resulting design configurations since the boundary shapes of the obtained design solution candidates can be easily converted to finite element models which are then used in large deformation analyses. Finally, the proposed design method is applied to design examples. The optimal configurations obtained by the proposed method provide good universal design performance, indicating the effectiveness and usefulness of the proposed method.
Automated Design of an Industrial Robot Family
Authors: Mandl Clemens , Feng Xiaolong , O¨lvander Johan
Published: July 2010

In this work, a methodology and an integrated tool framework has been developed for automated design of an industrial robot family consisting of four robot members. For each robot, performance requirements concerning payloads, reaches, and time performances are specified. A 3D design tool, namely SolidWorks, has been integrated with robot kinematics and dynamics simulation tools for simultaneous kinematics and dynamics design. A motor library comprising both geometric data and physical data has also been integrated in the tool framework. The automated design of the robot family has been formulated as a multi-objective and mixed variable design optimization problem. The arm modules are treated as continuous design variables while the motors are treated as discrete variables. Due to the characteristics of this mixed variable design optimization problem a genetic algorithm (GA) has been used. This work has successfully demonstrated the feasibility for achieving automatic design of an industrial robot family.
Design Approach of Gear Teeth Number for Vehicle Transmission Considering Human Aural Characteristics
Authors: Araragi Takayuki , Nagata Masaki , Uenishi Yasuhiro , Hirogaki Toshiki , Aoyama Eiichi , Miyazawa Masaya
Published: July 2010

The principal method for reducing meshing transmission error has been to design the gear with as many teeth as possible. However, while such design methods have focused on decreasing gear noise, they have not considered the relationship between gear noise and the background noise of vehicle interiors. Therefore, we propose a new design method of low noise gear that is based on human aural characteristics. The proposed method is a gear design that controls the frequency of the gear noise by changing the number of tooth. First, human aural characteristics were researched in a special acoustic environment in a vehicle. Second, the characteristics of vehicle interior sound were investigated. Third, the relationship between the number of teeth and the sound level of the gear noise was investigated. Finally, we demonstrated that the design of our proposed method, which was effective due to the design of optimum number of gear teeth considering human aural characteristics. It was able to be proven that the case of advancement of vehicle interior sound is achieved by considering human aural characteristic.
Lubricant Influence on Gear Efficiency
Authors: Michaelis Klaus , Ho¨hn Bernd-Robert , Doleschel Andreas
Published: July 2010

Power loss in a transmission is strongly related to the properties of the gear lubricant. Viscosity of the lubricant determines the no-load splash and churning losses. The losses in the EHD regime depend on the base oil type. In the boundary and mixed lubrication regime losses are mainly related to the chemical composition of the additive system. A test method was developed to evaluate the frictional properties of candidate transmission lubricants in relation to a mineral reference oil ISO VG 100 with a typical sulphur-phosphorus additive package. The test results can be expressed in simple correlation factors for no-load, EHD and boundary lubrication conditions, in comparative steady-state temperature development for given mean values of operating conditions, and in a ranking scale of different candidates. For a more detailed analysis of the expected power loss in a transmission in practice the results of the efficiency test can be introduced into an equation for the mean coefficient of gear friction for the respective oil. Thus the test results can be applied to any gear in practice at any operating conditions for any gear geometry. Examples of the influence of viscosity, base oil and additive type on the frictional behavior of gear lubricants and their effect on power loss reduction and energy savings in a gearbox are discussed.
A Screw Theory Approach for the Type Synthesis of Compliant Mechanisms With Flexures
Authors: Su Hai-Jun , Dorozhkin Denis V. , Vance Judy M.
Published: July 2010

This paper presents a screw theory based approach for the type synthesis of compliant mechanisms with flexures. We provide a systematic formulation of the constraint-based approach which has been mainly developed by precision engineering experts in designing precision machines. The two fundamental concepts in the constraint-based approach, constraint and freedom, can be represented mathematically by a wrench and a twist in screw theory. For example, an ideal wire flexure applies a translational constraint which can be described a wrench of pure force. As a result, the design rules of the constraint-based approach can be systematically formulated in the format of screws and screw systems. Two major problems in compliant mechanism design, constraint pattern analysis and constraint pattern design are discussed with examples in details. This innovative method paves the way for introducing computational techniques into the constraint-based approach for the synthesis and analysis of compliant mechanisms.
A Low-Cost Tool for Gathering and Interpreting the Mobility Needs of Wheelchair Users in India
Authors: Pearlman Jon , Cooper Rory , Chhabra H. S. , Jefferds Alexandra , Anbarasan Ilanagai
Published: July 2010

Collecting and interpreting customer needs using traditional product development tools can be difficult or impossible when there is a large geographic, cultural, or social gap between the customer and product designer. As part of a project to design an electric powered wheelchair (EPW) for Indians with disabilities, we piloted a new approach to gather and interpret customer needs. First, we distributed cameras to manual wheelchair users at the Indian Spinal Injury Center in New Delhi, India, and asked subjects take photos and write descriptions of accessibility barriers in and around their homes. The film was then processed; photos were de-identified and integrated into an internet-based questionnaire. Individuals with expertise in wheelchair use and design, and home modifications were recruited to participate in the questionnaire where they identified and ranked the accessibility barriers in each of 50 images which were randomly selected from the full database. Thirty cameras were received, yielding approximately 500 photos which were integrated into the questionnaire. A total of 72 subjects from 8 countries participated in the questionnaire. Using cluster analysis, we developed unique groupings for accessibility barriers based on their severity and prevalence. These groupings provided valuable and relevant information to develop and prioritize the design specifications of the EPW.
UAS Mission Path Planning System (MPPS) Using Hybrid-Game Coupled to Multi-Objective Optimiser
Authors: Lee DongSeop , Periaux Jacques , Gonzalez Luis Felipe
Published: July 2010

This paper presents the application of advanced optimization techniques to Unmanned Aerial Systems (UAS) Mission Path Planning System (MPPS) using Multi-Objective Evolutionary Algorithms (MOEAs). Two types of multi-objective optimizers are compared; the MOEA Non-dominated Sorting Genetic Algorithms II (NSGA-II) and a Hybrid Game strategy are implemented to produce a set of optimal collision-free trajectories in three-dimensional environment. The resulting trajectories on a three-dimension terrain are collision-free and are represented by using Be´zier spline curves from start position to target and then target to start position or different position with altitude constraints. The efficiency of the two optimization methods is compared in terms of computational cost and design quality. Numerical results show the benefits of adding a Hybrid-Game strategy to a MOEA and for a MPPS.
An Approach to Support the Implementation of Product Configuration Tools
Authors: Raffaeli Roberto , Mengoni Maura , Germani Michele , Mandorli Ferruccio
Published: July 2010

Companies applying mass customization paradigm regard the design process as a configuration task where the solution is achieved through the extraction of a new instance from a modular product structure. In this context product configuration management tools are evermore important. Although tools have been already proposed, they fail in real industrial contexts. Main causes are recognizable in high efforts in systems implementation and lack of flexibility in products updating. This research aims to develop an approach to overcome drawbacks and simplify the implementation and the use of product configuration systems also in redesign activities. The paper initially reviews existing systems in terms of design knowledge representation methods and product structure formalization techniques. Then, an approach based on Configuration Virtual Prototypes which store and manage different levels of knowledge, is presented. In particular, a framework is outlined in order to represent design data and its formalization in configuration tools. Three different domains are managed and connected via Configuration Virtual Prototypes: Product Specifications, Geometrical Data and Product Knowledge. Specifically, geometrical data aspects are analyzed in detail providing approaches for eliciting knowledge introduced by parametric template CAD models. The approach will be exemplified through a real application example where an original tool has been developed on the based of the described method. Benefits of the system will be shown and briefly discussed, in particular in terms of reachable flexibility in solutions.
Comparison of Methods for Large Deflection Analysis of a Cantilever Beam Under Free End Point Load Cases
Authors: Morsch Femke M. , Tolou Nima , Herder Just L.
Published: July 2010

The objective of this paper is to present a comparative analysis for large deflections of a cantilever beam under free end point load. pseudo rigid body model (PRBM), non-linear beam theory numerically solved with integration (NLBT-NUM), linear beam theory (LBT), finite element modeling (FEM) using an available commercially FEM package, non-linear beam theory solved with direct nonlinear solution (NLBT-DNS) and experimental evaluation (EXP), have been implemented. For the purpose of comparison, the relation between the displacements, rotating angle of the tip and applied force were calculated and shown graphically. The accuracy of the path of the tip as a function of the force is compared with the NLBT-NUM, which is taken as a reference. In addition, computation times and implementation convenience were recorded. In the case of a perpendicular load, the PRBM is accurate and has little computation time. The NLBT-NUM, NLBT-DNS and FEM analysis are accurate, but the computation time is longer. The NLBT-DNS has been introduced for the first time and provides semi-exact closed form solutions for both horizontal and vertical position. In case of a non-perpendicular load, the NLBT-NUM and FEM analysis are the only accurate methods while computation time is less for the numerical solution. In conclusion, the PRBM and the FEM are recommended for the cases of perpendicular load and non-perpendicular load respectively. Finally, it can be concluded that the more accurate methods take more computation time, and that the accuracy is affected by load cases.
Efficient Simulation of Parallel Kinematic Machine Tools
Authors: Kipfmu¨ller Martin , Munzinger Christian
Published: July 2010

Today’s machine tool industry mainly consists of small and medium-sized enterprises. Thus, the simulation of new products often does not seem to be cost effective due to the small number of items produced and the high cost of simulation tools. Nevertheless, the use of simulation tools is essential in order to tap the full potential of new challenging concepts like parallel kinematic machines. This paper presents a simulation method supporting the development process of parallel kinematic machine tools from the first concept to the prototype. In order to render the method applicable for the machine tool industry, a special focus is placed on tool efficiency. A modular modeling concept will ensure that the structure of the first kinematic model of the concept phase can be enhanced during the development process and developed into more detailed models, e.g. for dimensioning calculations or to study the dynamic behavior of machine tools. Thus, the method efficiently supports the whole development process with a simulation model gradually increasing in detail according to the requirements of the machine tool designer.
Spring-to-Spring Balancing as Energy-Free Adjustment Method in Gravity Equilibrators
Authors: Barents Rogier , Schenk Mark , van Dorsser Wouter D. , Wisse Boudewijn M. , Herder Just L.
Published: July 2010

Generally, adjustment of gravity equilibrator to a new payload requires energy, e.g. to increase the pre-load of the balancing spring. A novel way of energy-free adjustment of gravity equilibrators is possible by introducing the concept of a storage spring. The storage spring supplies or stores the energy necessary to adjust the balancer spring of the gravity equilibrator. In essence the storage spring mechanism maintains a constant potential energy within the spring mechanism; energy is exchanged between the storage and balancer spring when needed. Various conceptual designs using both zero-free-length springs and regular extension springs are proposed. Two models were manufactured demonstrating the practical embodiments and functionality.
Dynamic Analysis of a Specific 2PRR Robotic Manipulator
Authors: Voglewede Philip A. , Copsey Robert
Published: July 2010

Parallel mechanisms including the 2PRR have opened new horizons for the industrial robotics designer. Enhancements in terms of speed, stability, precision and cost reduction are attainable when compared to higher degree of freedom serial designs. This comes at the cost of a reduced workspace and a more challenging dynamic analysis. The nature of the closed kinematic chain dictates that the application of Newton-Euler analysis methods becomes cumbersome, as the systems of equations describing the dynamics must be solved simultaneously. Moreover, the use of these methods within the context of the parallel mechanism fails to provide designer with the insights apparent from an explicit model. The application of Lagrangian analysis techniques to this robotic linkage is sought as a means of both simplifying the solution of the resulting dynamics and gaining the perspective which only the insight offered by an explicit model can provide.
Design Fixation on Non-Verbal Stimuli: The Influence of Simple vs. Rich Pictorial Information on Design Problem-Solving
Authors: Cardoso Carlos , Badke-Schaub Petra , Luz Ana
Published: July 2010

During design problem-solving designers frequently come across a variety of rich visual displays. While browsing for different external sources of information, pictorial representations of existing concepts take a relevant prominence. However, once designers start devising new solution ideas to design problems, they often become particularly influenced by the exemplars they come across. Inadequate and excessive reuse of existing (parts of) available solutions has been described as design fixation. Such behaviour has been discussed having an impact on creativity and innovation. The study presented here investigates the influence that two different types of pictorial representations (simple and rich stimuli) of a particular solution had upon industrial design students during an ideation phase. The findings clearly demonstrate high levels of design fixation on the pictorial examples utilised. The results also show the presence of both detrimental and beneficial aspects on the quality of the ideas generated. Lastly, the outcome of this study reports on how the originality of the solutions created by the groups primed with existing solutions was significantly hindered. Reasons for the occurrence of design fixation are discussed in light of its implications to design quality and originality; and ultimately, to the use of pictorial information in design practice.
Simulation and Optimization of the Water-Jet Cleaning Process
Authors: Krishnamurthy Adarsh , Li Wei , McMains Sara
Published: July 2010

Mechanical components are cleaned after manufacturing processes like casting and machining using high pressure waterjets that help in both dislodging and removal of contaminants. In order to understand the dynamic relationships that exist in an actual cleaning process, it is essential to visualize the interaction of the water-jet with the part geometry. To aid in this, we have developed a simplified model of the water-mill that simulates the cleaning process on parts represented using standard CAD geometries. Our model of the cleaning process approximates the water-jets in a water-mill as a set of rays originating from the nozzles and evaluates the pressure the water-jet exerts when it hits the surface of the part. This model can be used to understand the effect of kinematic parameters like nozzle diameter and standoff distance on cleaning. Furthermore, this model can be used to optimize these parameters. Any standard optimization technique can be used for this optimization. As proof of concept, we used a Genetic Algorithm (GA) to optimize the process parameters for the simplified cleaning process on a flat plate and a curved surface. Analysis of the results indicates that the obtained solution is theoretically an optimum.
Stiffness and Mass Detection of Nano Layers Using Piezoresponse Force Microscopy
Authors: Bashash Saeid , Salehi-Khojin Amin , Jalili Nader , Thompson Gary Lee , Vertegel Alexey , Mu¨ller Maren , Berger Rudieger
Published: July 2010

Piezoresponse force microscopy (PFM) is proposed in this article as a new technique for identification of elastically distributed thin layers on top of microcantilever sensors. Using the conventional actuation methods such as base excitation, the ratio of stiffness over the layer mass per unit length affects the resonant frequencies of the system as a single parameter. However, due to tip/sample elastic contact in PFM, these two parameters can be separately identified using the frequency shifts before and after attaching the layer. The concept is theoretically proven here using the modal analysis of the system. For practical verification, three gold-coated AFM microcantilevers were primarily tested for their initial resonant frequencies. The Focused Ion Beam (FIB) technique was then employed to deposit thin layers of Pt-based material in different configurations on the cantilevers’ surfaces. The microcantilevers were then reexamined for their new resonances, and the properties of the deposits were identified using a robust system identification procedure. Results indicate acceptable estimation of the cantilevers’ added mass and stiffness, making the technique suitable for detection of elastically distributed biological species.
Tele-Operated Microsystems Laboratory
Authors: Sivakumar Ganapathy , Mulsow Matt , Mellinger Aaron , Lacouture Shelby , Dallas Tim
Published: July 2010

This paper presents the architecture for a remotely controllable and interactive MEMS laboratory. There have been significant advances in computer simulations of MEMS devices, but laboratory testing of devices still plays a crucial role in developing a detailed understanding of MEMS performance. New computer and networking technologies, have allowed the construction of remotely controllable labs for fields spanning education and technology. The main idea of this work is to allow a user in any part of the globe to carry out real-time experiments on a MEMS device using a computer with internet connectivity. The user also has the option of using a commercially available haptic device to feel the magnified nano/micro-scale forces associated with the devices while actuating them. The present interface was tested on a two degree-of-freedom (XY) electrostatic MEMS positioning microstage and a MEMS microgripper.
Gait and Gait Transition for a Robot With Two Actuated Spoke Wheels
Authors: Wang Ya , Ren Ping , Hong Dennis
Published: July 2010

This paper presents work on the gait and gait transition analysis for a novel mobile robot that uses two actuated spoke wheels. Gait transitions, known as acyclic feed forward patterns, allow the robot to switch from one type of gait to another during walking and turning. The mobile robot IMPASS (Intelligent Mobility Platform with Active Spoke System) uses a unique mobility concept for locomotion, thus gait transition plays an important role in generating gait patterns to walk and turn. The primary focus of this paper is how to perform gait transition between gaits in walking direction. First, the basic gait patterns for steering and straight line walking are presented. More specifically, the critical gait parameterizations and the possible foot positions in different gait patterns to produce capable steering locomotion over terrain are presented. Since IMPASS is expected to utilize its metamorphic configurations to carry out gait transitions, the extending forward and inverse analyses are also presented based on previous work about topology classification and mobility analysis for IMPASS. Then the gait transition analysis and simulation of typical patterns are performed. The results from this work lay the foundation for the future research on trajectory and path planning for IMPASS.
A Strategic Idea Generation Method for Eco-Business Planning
Authors: Kondoh Shinsuke , Mishima Nozomu
Published: July 2010

Environmental consciousness has gained increasing interest in recent years, and product life cycle design that aims to maximize total value while minimizing environmental load and costs should be implemented. To achieve that, the processes of idea generation and decision-making for eco-business strategies, as well as the design of a target product and its life cycle options, should be systematically supported. This paper proposes a strategic decision-making method for eco-business planning so that a designer can easily find a set of eco-business ideas that effectively improve environmental and economic performance simultaneously. A decision-making procedure based on this method is also illustrated with a simplified example of a laptop computer business.
History and Creativity in Mechanical Engineering Education
Authors: Rosa Francesco , Rovida Edoardo
Published: July 2010

In spite of its common perception as a static matter, the history of mechanical engineering is always a surprisingly rich source of ideas and constructive solutions. In fact, a historical perspective leads to a deeper understanding of the reasons why some technical solutions are commonly adopted, and that may not emerge from a technical and economical analysis of the present situation. Moreover, the power of invention of a “creative engineer” is limited to what can actually be done and is useful; therefore his/her creativity relies on a wide and deep technical knowledge. These two apparently simple and obvious considerations are the starting points to establish a relationship between history and creativity in the mechanical engineering field. The introduction of the historical heritage in purposely developed courses to stimulate the creativity of young engineers is one of the beneficial effects of this association. The breadth of the historical heritage is the more evident difficulty of this approach. The proposed way to overcome this difficulty, making it more easily accessible especially for younger engineers, consists in organizing the historical heritage in archives and data-bases. Two strategies (named abstraction and evaluation) to develop new solutions starting from the results of the search in these data-bases are also presented and discussed. This approach has been introduced in the syllabus of the courses “History of mechanical engineering” and “Design Methods” that are comprised in the Master of Science in the Mechanical Engineering Programme of the Politecnico di Milano.
Product Function: Component Modeling Using Rough Sets
Authors: Miwa Toshiharu , Aoyama Hideki
Published: July 2010

The acceleration of the product development cycle continues to be a significant challenge for manufacturing firms around the world. The misunderstanding of important relationships between product functions and components leads the delay of product development. The present paper describes an identification method of the relationships between product functions and components at the early stage of product development. The proposed product function-component modeling method using rough sets theory extracts the characteristic relationships between product functions and components from a small amount of the qualitative and linguistically-expressed knowledge data. The advantage of using the rough sets is that the combination of necessary and possible sets (lower and upper approximations) represents the vague knowledge. The present paper describes an example of a conventional cutting process with 6 manufacturing parameters that this method contributes to the identification of cutting mechanism from a small amount of sampling data (7% of whole event) compared to the conventional statistical modeling method.
A Comparative Study of Data-Intensive Demand Modeling Techniques in Relation to Product Design and Development
Authors: Tucker Conrad S. , Hoyle Christopher , Kim Harrison M. , Chen Wei
Published: July 2010

This paper presents a comparative study of choice modeling and classification techniques that are currently being employed in the engineering design community to understand customer purchasing behavior. An in-depth comparison of two similar but distinctive techniques — the Discrete Choice Analysis (DCA) model and the C4.5 Decision Tree (DT) classification model — is performed, highlighting the strengths and limitations of each approach in relation to customer choice preferences modeling. A vehicle data set from a well established data repository is used to evaluate each model based on certain performance metrics; how the models differ in making predictions/classifications, computational complexity (challenges of model generation), ease of model interpretation and robustness of the model in regards to sensitivity analysis, and scale/size of data. The results reveal that both the Discrete Choice Analysis model and the C4.5 Decision Tree classification model can be used at different stages of product design and development to understand and model customer interests and choice behavior. We however believe that the C4.5 Decision Tree may be better suited in predicting attribute relevance in relation to classifying choice patterns while the Discrete Choice Analysis model is better suited to quantify the choice share of each customer choice alternative.
Conservative Prediction via Safety Margin: Design Through Cross-Validation and Benefits of Multiple Surrogates
Authors: Viana Felipe A. C. , Picheny Victor , Haftka Raphael T.
Published: July 2010

The use of surrogates for facilitating optimization and statistical analysis of computationally expensive simulations has become commonplace. Usually, surrogate models are fit to be unbiased (i.e., the error expectation is zero). However, in certain applications, it might be interesting to safely estimate the response (e.g., in structural analysis, the maximum stress must not be underestimated in order to avoid failure). In this work we use safety margins to conservatively compensate for fitting errors associated with surrogates. We propose the use of cross-validation for estimating the required safety margin for a given desired level of conservativeness (percentage of safe predictions). We also check how well we can minimize the losses in accuracy associated with conservative predictor by selecting between alternate surrogates. The approach was tested on two algebraic examples for ten basic surrogates including different instances of kriging, polynomial response surface, radial basis neural networks and support vector regression surrogates. For these examples we found that cross-validation (i) is effective for selecting the safety margin; and (ii) allows us to select a surrogate with the best compromise between conservativeness and loss of accuracy. We then applied the approach to the probabilistic design optimization of a cryogenic tank. This design under uncertainty example showed that the approach can be successfully used in real world applications.