Implicit shape parameterization for Kansei design is a procedure that use 3D-models, or concepts, to span a shape space for surfaces in the automotive field. A low-dimensional, yet accurate shape descriptor was found by Principal Component Analysis of an ensemble of point-clouds, which were extracted from mesh-based surfaces modeled in a CAD-program. A theoretical background of the procedure is given along with step-by-step instructions for the required data-processing. The results show that complex surfaces can be described very efficiently, and encode design features by an implicit approach that does not rely on error-prone explicit parameterizations. This provides a very intuitive way to explore shapes for a designer, because various design features can simply be introduced by adding new concepts to the ensemble. Complex shapes have been difficult to analyze with Kansei methods due to the large number of parameters involved, but implicit parameterization of design features provides a low-dimensional shape descriptor for efficient data collection, model-building and analysis of emotional content in 3D-surfaces.

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We propose a switching control strategy for systems with state and control constraints. Prior studies have proven that switching control strategies have the ability to meet performance objectives, such as fast response and good disturbance rejections, while avoiding constraint violations. The controller is selected on-line from a given set of controllers by supervisory rules based on the concept of a maximal output admissible set. The selected controller needs to be appropriately initialized during switching, but how to decide the controller's initial state is still a problem. This paper proposes a method that utilizes an initial value compensation (IVC) technique for determining the initial state of the controller. The IVC technique has the following features. First, the controller's initial state is chosen according to the plant's initial state. Therefore, the number of variables that the supervisory rules need to consider is reduced. Second, smooth and fast transient responses can be obtained after switching, therefore the region of the closed-loop initial state variables that satisfy the desired response specifications under the given constraints can be expanded. Experimental evaluations of the proposed switching control strategy were performed with a 2.5-inch form-factor hard disk drive.

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To deal with the diversification of consumers' needs and to survive in the severe competitive environment, a grate deal of effort has been paid by manufacturers. Respecting the background, importance of effective lot sizing has been focused. Although variety of lot sizing algorithms has been proposed, most of their objective functions are based on time and quantity criteria. However, it is difficult to select an appropriate criterion universally, because the most important criterion is changed dynamically in real manufacturing environment. Then product cost seems to be a universal criterion, since profit is generally quite important factor in manufacturing enterprises. On the other hand, a concept of Distributed Virtual Factory (DVF) has been proposed as a new simulation environment for evaluating the performance of whole manufacturing systems. By performing simulation with DVF, all the information required to product cost calculation can be obtained. In this study, we propose an effective lot sizing methodology which performs Activity Based Costing (ABC) and minimizes product cost directly. We clarify the validity of the proposed lot sizing method through simulation experiments with DVF.

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This paper presents essence and results of experimental investigations of highly efficient automated internal cylindrical grinding method. The essence of this method consists in the removal of the whole grinding allowance in one pass of a grinding wheel, parallel to preserving the required quality of the surface layer of a workpiece. A grinding wheel applied to the developed method had a zonal diversified internal structure and a properly prepared conical chamfer.

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In this paper a spatial rigid-elastic coupling multibody dynamic model is first developed for the parallel mechanism of a hybrid type parallel kinematic machine. The dynamic characteristics of the parallel mechanism are then investigated in detail, based on the developed dynamic equations and finite element model. Simulation results show that the first three orders of fundamental frequencies are dominant factors that influence the dynamic characteristics of the hybrid type parallel mechanism. The multi-objective optimization model is then presented with consideration of fundamental frequency index, driving force index, workspace index and dexterity index. By a goal attainment method, the optimal results are obtained, which are afterwards verified the global optima by means of multiple initial points analysis. The research of this paper provides a methodology for dynamic modeling and design for the kind of parallel kinematic machines.

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When influence coefficient (IC) method is used in rotor balancing, it is possible that serious errors could be resulted in unbalance determinations due to the contamination of measurements and IC matrix being ill-posed. In this study, the availability of least squares algorithm (LSA) and Tikhonov regularization (TR) is studied by error estimations of unbalance determination with considering measurement errors. Also, the influence of illness of the IC matrix equation on the change of balancing accuracy relative to the measurement error will be simulated. The finite element method is used to analyze unbalance responses of a rotor-bearing system and the analysis results of both TR and LSA are compared in case studies. Furthermore, the validations of both methods are realized by balancing experiments of a rotor kit.

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This paper proposes a simplified analysis model of complex solid structure for three-dimensional bodies (3D-bodies) in the First Order Analysis (FOA). A simplified finite element composed of the beam elements is suggested for the deformation analysis of 3D-bodies by extending concept of conforming beam element for the finite element method (FEM). When a complex solid structure is simplified to an assemblage of simple elements applied element forces such as axial forces, shear forces, bending moments as well as twisting moments, the total stiffness equation for the FOA of the solid structure is constructed approximately and solved for the given boundary and loading conditions by the usual manner of the FEM. Then, the total deformation of the complex structure is estimated by the simplified model and the element forces are calculated in the element level. It is found that the finite element analysis via developed simplified element analysis can estimate deformations of complex 3D-bodies in a rational precision, and the results of the analysis are useful for considering the load transmitting path of the structure and for designing a better structure by changing the stiffness of structural components.

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In order to investigate the influence of shot peening on the surface durability of case-hardened steel gears, the case-hardened steel gears shot-peened with different shot velocities and shot diameters were fatigue-tested using a power circulating type gear testing machine. The hardness, the compressive residual stress and the surface roughness of the gears were increased by shot peening. The cause of failure of all the test gears was pitting due to surface cracking. The surface durability of the gear shot-peened under medium condition in this experimental range was higher than that of the non-peened gear. On the other hand, that of lightly or strongly shot-peened gear was just as high. Judging from the p_max-N curves and also the [A(σ_y/H_V)]_max-N curves, it is denoted in this experimental range that the surface durability of case-hardened steel gears was influenced by the hardness and the surface roughness of the gears. Therefore, it is proposed in this experimental range that the medium shot peening condition, that is, 60m/s shot velocity and 0.6mm shot diameter, should be selected in order to improve the surface durability of case-hardened steel gears.

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Speed and efficiency are necessary in the field of mechanical design. CAD/CAM/CAE technologies have advanced and attention has also been paid to increasing the efficiency of data sharing and agent processes in the web environment. In this paper, Semantic Web technology is used to enable the sharing of metadata. The metadata consists of design documents and design formulas, with additional semantic information inserted. Mathematical information is expressed by adding metadata into conventional mechanical design formulas using a Resource Description Framework (RDF). The design formulas are later written in MathML (Mathematical Markup Language) for the sake of data sharing. In this way, data sharing and advanced searching is made easy, because the relevant information is made machine readable in the web environment. The calculation of design formulas is made possible using a mathematical processing system, thus increasing the efficiency of mechanical design.

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The vibration of the helical gear system is generated by three kinds of excitation. The first cause is a displacement excitation due to the tooth surface error. The second is a parametric excitation by the periodical change of the tooth mesh stiffness. The third is a moving load on the tooth surface during the progress of mesh of the teeth. In mesh of a pair of helical gears, the composite load of the distributed load along a contact line moves its operating location from one end of face width to the other end during the process of mesh progress. This moving load causes fluctuation of bearing load that excites the housing. Therefore, it is important to treat gear mesh excitation as moving load problem. For this purpose, a tooth mesh model, in which three different types of excitations above are incorporated, is proposed. In this model, a pair of gear tooth is represented by the multiple springs and the moving load can be taken into account by the multiple mesh excitation forces that have the phase differences from each other. This model is applied to the vibration analysis of a single stage gearbox. The analytical and experimental results show that this method is accurate and effective enough for practical use.

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It is known that detachment waves are generated on the surface of a soft material when it is slid on a hard surface under certain conditions. In the present study, the variation in the contact area that arises when a plate of a cross-linked polymer, poly-dimethylsiloxane (PDMS), is slid in contact with a glass hemisphere has been measured every 2 ms using a microscope and high-speed camera. The measurements elucidate that the behavior of the PDMS surface under sliding friction is divided into three modes. In mode I, a detachment wave is generated and it propagates across the contact zone. In mode II, a detachment wave is generated but does not propagate perfectly. In mode III, no detachment waves are generated. The Young modulus and load control the generation of detachment waves, but the contribution of the former is approximately 8 orders of magnitude larger than that of the latter.

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This paper studied the material ordering and inventory control of supply chain systems. The effect of controlling policies is analyzed under three different configurations of the supply chain systems, and the formulated problem has been solved by using an evolutional optimization method known as Differential Evolution (DE). The numerical results show that the coordinating policy with the incentive scheme outperforms the other policies and can improve the performance of the overall system as well as all members under the concept of supply chain management.

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In this paper we propose an algorithm for learning from positive examples only, based on a modified cognitive control model. This problem arises when positive examples are readily available while negative examples are difficult or impossible to obtain. In particular, we are motivated by an application of the proposed algorithm to learning strategies from real-life optimisation problem solutions provided by skilled humans. Using a packing problem as an example, we performed an experiment in which the performance of the proposed algorithm was compared to that of one-class Support Vector Machines and auto-encoding neural network algorithms. The results of the experiment show that the proposed algorithm compares favourably to the other two algorithms.

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A vibration-assisted tapping system has been developed in which a piezoelectric-zirconate-titanate (PZT) oscillator applies small-amplitude vibrations to a workpiece and a torque transducer measures the time-evolving torque during the tapping process. To investigate the roles of metalworking fluids, four different metalworking conditions have been examined: without metalworking fluids (dry), with an additive-free fluid (base oil), with an oiliness-agent-containing fluid (fluid A), and with an extreme-pressure-agent-containing fluid (fluid B). The time evolutions of the tapping torque have been obtained for tapping M3 threads in S45C steel with varying vibration amplitudes, vibration frequencies, and tapping speed. It has been found that the present system decreases the tapping torque; in particular, a decrement of up to 14% in the tapping torque is obtained for fluid A using 800-Hz vibrations with an amplitude of 5 μm at a tapping speed of 3 rpm. Increments in the vibration amplitude and frequency lead to decrements in the tapping torque, but the effect of the vibration tends to fade with increasing tapping speeds. It appears that vibrations enhance not only the physical effects but also the chemical effects of metalworking fluids.

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A high positioning accuracy of feeding system is one of heavy component in precision machine systems, and its compensation method for positioning accuracy is also an important technique in feeding systems. The compensation method provides the prediction of positioning errors and correction of positioning accuracy in control systems. In this paper, a two-dimensional compensation method for XY feed system in CO₂ laser machine will be introduced. First, positioning errors of XY tables are measured by a CCD image processing system, by using a standard specimen. Then the two-dimensional compensation function can be determined from the two-dimensional positioning errors curve of the XY feeding system-the system responsible for correcting the positioning error of the XY table. Finally, the position error of XY feeding system that used the method to correct its positioning errors is measured by a HP 5519A Interferometer, and verified that it effectively increased the positioning accuracy of XY table. According to the compensation experiments, the X-axis of the XY feeding system decreased from 7 microns to 2.8 microns and the Y-axis is from 17 microns to 2.6 microns. In addition, the compensation method does not decrease the perpendicular accuracy and the repeatability accuracy of XY feeding systems.

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