Development Of Design Methods Research Articles

Designing spline broaches of optimal structure

Methods of designing spline broaches of optimal structure according to smallest length of body are described. Multitude of broach designs may be explained by summation of geometric, structural and operating parameters of working and tail parts. In order to evaluate the efficiency of spline broaches, a system of functions characterizing length of broach, round and chamfer parts in accordance with the cutting pattern is introduced. A system of structural and technological limitations over basic features of broaches is supported. Mathematical optimization model of a broach consisting of a sum of target functions and constraint system is put together. Choice of optimal solution is based on implementation of linear programming algorithms. Optimal methods of designing spline broaches are determined using MS Excel. The developed design method is applicable for comparative evaluation of spline broaches of various designs with various cutting and cut-off patterns and allows to form the entire sum of broach designs according to set input parameters and to choose the most efficient one which would correspond to minimal length of the tool.

Design of a Hand Rehabilitation Device Using integrated Axiomatic and Benchmarking Methods

The diversity of users and market requires that product must be developed based on the customer need. It is a challenge for designers to fully understand the customer need in the product development. Traditional methods of the product development rely on designers’ experience. It is difficulty to generate a consistent design solution by different designers. This paper introduces an integrated approach of axiomatic design and benchmarking methods for product development based on diverse needs. The axiomatic principle is applied to map customer needs into product function requirements. The benchmarking method is used to search product specifications to meet the product function requirements. A hand rehabilitation device is developed using the proposed method. The solution shows effectiveness of the proposed method.

A Systematic Optimization Design Method for Complex Mechatronic Products Design and Development

Designing a complex mechatronic product involves multiple design variables, objectives, constraints, and evaluation criteria as well as their nonlinearly coupled relationships. The design space can be very big consisting of many functional design parameters, structural design parameters, and behavioral design (or running performances) parameters. Given a big design space and inexplicit relations among them, how to design a product optimally in an optimization design process is a challenging research problem. In this paper, we propose a systematic optimization design method based on design space reduction and surrogate modelling techniques. This method firstly identifies key design parameters from a very big design space to reduce the design space, secondly uses the identified key design parameters to establish a system surrogate model based on data-driven modelling principles for optimization design, and thirdly utilizes the multiobjective optimization techniques to achieve an optimal design of a product in the reduced design space. This method has been tested with a high-speed train design. With comparison to others, the research results show that this method is practical and useful for optimally designing complex mechatronic products.

A Hierarchy of Architectural Design Elements for Energy Saving of Tower Buildings in Korea Using Green BIM Simulation

There is a great interest in building information modeling (BIM) and energy saving worldwide. In reality, however, insufficient studies have been conducted on the development of design methods to perform energy performance analysis. Thus, there is a problem that it is difficult to objectively obtain reliability in energy performance assessment of architectural designs such as scale and size of buildings. In addition, the energy performance analysis is considered as a different field from eco-friendly design methods, and there is another problem that low-carbon design methods more dependent on thermal insulation performance and heating ventilation and air-conditioning (HVAC) system than on original design methods are mainly developed. In order to solve this problem, this study aims to develop design methods capable of considering energy performance from the early design stage. Designers are required to intuitively understand the results through energy performance analysis using BIM tools and to reflect them in design. To this end, this study analyzed the correlation with energy performance using only basic architectural design elements with mass buildings. This has the advantage of establishing more free mass design mass design considering energy performance even if design and main structure are yet to be determined.

New design method for multi‐stack disc‐type hysteresis motors based on analytical calculations

Hysteresis motors are widely employed for a variety of high speed applications, thanks to their unique features. Usual design methods could not be used for these motors since the operation mechanism of hysteresis motors is also unique. However, an appropriately developed design method has not been provided by the few relevant published works. This study presents a new iterative design method, which is capable of being used for almost all hysteresis motor structures. Also, it is almost independent of the approach of obtaining the design equations. Multi-stack disc-type slotless structure has been selected as the case study, because of its interesting capabilities. Its design equations are derived by combining the fundamental laws of electromagnetism with the elliptical model of hysteresis loops. Some new techniques are introduced to increase the accuracy of these equations. A sample motor has been designed by applying the direct search optimisation to the proposed design method. The prototyped sample motor has been subjected to various tests. The measured operating characteristics show a great agreement with the design requirements.

Live Beyond Buildings: The street as the everyday living space in Istanbul, Turkey

This paper attempts to reveal the importance of the everyday temporal living space on the street as the agency to improve the quality of life in the city. The temporal living space is the collective public space that is produced by the local inhabitants as the response to fulfil their sociocultural needs. This study employed time-based behavioural and spatial mappings to reveal how spatial alteration was employed by the locals, producing the particular spatial programming and atmospheres that allowed the interiorization of the street. The mappings would also reveal how the interaction of the local inhabitants within this temporal living space had impacts on the general wellbeing and the spatial identity of the city. The findings of this study were translated into an interior architectural design exercise, by developing design methods that were adopted from the locals’ spatial mechanisms in producing their temporal outdoor living spaces.

Developing design methods of concrete mix with microsilica additives for road construction

Based on the laboratory test results, regression equations having standard cone and concrete strength, to determine the available amount of cement, water and microsilica were obtained. The joint solution of these equations allowed the researchers to develop the algorithm of designing heavy concrete compositions with microsilica additives for road construction.

The Approximate Correctness of Systems Based on δ-bisimulation

The correctness of system is an important attribute to quantify the quality. δ-bisimulation based on complete lattices have been proposed to generalize the classical bisimulation. To analyze the implementations of system approximates its specification step by step, the infinite evolution mechanism of δ-bisimulation is established. Firstly, the relations between the implementations and specification under δ-bisimulation are analyzed, δ-limit bisimulation is defined and some examples of δ-limit bisimulations are given. Then, δ-bisimulation limit is proposed to state the specification is the limit of implementations. Some algebraical properties of δ-bisimulation limit are proved. Finally, in order to use the flexible hierarchic development and modular design methods to archive the limit, the continuous of δ-bisimulation limit under various combinators are showed.

Explicit Input Signal Design for Stable Linear Ensemble Systems

The control of ensemble systems arising in multiple science and engineering domains has recently received increased attention due to a number of newly emerging applications. While structural controllability of linear ensemble systems has been extensively studied, the problem of constructing an actual input signal that will steer an ensemble system between arbitrarily given ensemble states remains a challenging task. In this paper, we consider a class of continuous-time stable linear ensemble systems and design explicit control laws to steer such ensembles between states of interest. The control is synthesized using the discrete-time counterpart of the original continuous-time ensemble system. Simulations are provided to demonstrate the effectiveness of the developed design method.

Flat Panel Light-Field 3-D Display: Concept, Design, Rendering, and Calibration

Recent autostereoscopic 3-D (A3D) displays suffer from many limitations such as narrow viewing angle, low resolution, and shallow depth effects. As these limitations mainly originate from the insufficiency of pixel resources, it is not easy to obtain a feasible solution that can solve all the limitations simultaneously. In many cases, it will be better to find a good compromising design. Generally, the multiview display and the integral imaging display are the representative designs of A3D. However, as they are too canonical and lack flexibility in design, they tend to be a tradeoff. To address these design issues, we have analyzed the multiview display and the integral image display in a light-field coordinate and developed a 3-D display design framework in a light-field space. The developed framework does not use the “view” concept anymore. Instead, it considers the spatial distribution of rays of the 3-D display and provides more flexible and sophisticated design methods. In this paper, the developed design method is explained using a new pixel value assigning algorithm, called the light-field rendering, and vision-based parameter calibration methods for 3-D displays. We have also analyzed the blur effects caused by the depth and display characteristics. By implementing the proposed method, we have designed a 65-in 96-view display with a 4K panel. The developed prototype has showed almost seamless parallax with a high-resolution comparable to the conventional four to five views displays. This paper will be useful to readers interested in A3D displays, especially in the multiview and the integral imaging displays.

Finite-time state estimation for jumping recurrent neural networks with deficient transition probabilities and linear fractional uncertainties

This paper is concerned with the finite-time stability and the finite-time boundedness issues on the estimation problem for a class of continuous-time uncertain recurrent neural networks with Markovian jumping parameters. The uncertain parameters are described by the linear fractional uncertainties and the jumping parameters obey the homogeneous Markov process with possibly deficient probability transition matrix. A full-order state estimator is constructed to estimate the neuron state, in presence of the uncertain and jumping parameters, such that the resulting error dynamics of the state estimation is (i) finite-time stable in the disturbance-free case; and (ii) finite-time bounded in case of exogenous disturbances on the measurements. By employing the Lyapunov stability theory and stochastic analysis techniques, sufficient conditions are established that ensure the existence of the desired finite-time state estimator, and then the explicit expression of such state estimators is characterized in terms of the feasibility to a convex optimization problem that can be easily solved by using the semi-definite programme method. Validity and effectiveness of the developed design method are demonstrated by a numerical example.

DESIGN METHOD OF PIN ENGAGEMENT DRIVE SPROCKETSWITH RUBBER-REINFORCED TRACKS OF TRACTION AND TRANSPORTATION VEHICLES

Nowadays rubber-reinforced tracks found wide application on different purpose traction and transportation vehicles due to well-known advantages, including possibility of their installation instead of metal linked tracks without significant modernization of undercarriages structures. The operational experience of vehicles with rubber-reinforced tracks shows that their construction differences in comparison with metal tracks provide increased loading to crawler outline, especially to drive sprockets. It shows on necessity of individual drive sprockets design for rubber-reinforced tracks. Special methods for this are absent and traditional methods intended for metal tracks do not provide reliability and efficiency of track engagement. The article contains the special designed method of pin engagement drive sprockets with rubber-reinforced tracks engineering. Practically established that rubber-reinforced track bending is going through the broken line in conditional joints and the engagement element with the drive sprocket tooth is spool of inset element with the part of reinforce lay. All the necessary analytical dependences for drive sprockets design and calculation are shown. The optimal values of contact angle for real constructions of rubber-reinforced tracks, when the normal teeth form is provided; analytical dependences of kinematic pitch circle and bottom circle radiuses for different variations of conditional joints are determined. Boundary conditions for optimal values determination of drive sprockets width and thickness and also their heads radius are accounted. The efficient options of drive sprockets teeth profile curves plotting are shown. The developed design method of pin engagement drive sprockets with rubber-reinforced is based on typical methods for metal tracks and takes into account structural features of rubber-reinforced tracks. It provides reliability and efficiency of track engagement and can be used in design process of traction and transportation vehicles undercarriages.

Composite slim floor beams with innovative shear connections

An innovative form of slim floor beams is proposed in which the shear connection is formed by combining the concrete passing through the web openings with a steel tie-bar element. A numerical study was conducted to evaluate the flexural behaviour of these composite shallow cellular beams. The force transferring mechanism, load-bearing capacity and failure patterns of the shear connections were also evaluated. Two different configurations of shear connection were designed and a parametric study was carried out to determine the parameters likely to influence their performance. The findings were incorporated with bending and push-out test results to develop design methods for this form of shear connection. A tentative design procedure for the composite shallow cellular beams is proposed.

Theoretical model for the improved PCC pile using expansive concrete

Conventional PCC pile technique has been widely used as embankment piles for highway construction in China. To further improve the PCC pile capacity, the expansive concrete technique has been applied to the PCC pile to replace the normal concrete recently. The use of expansive concrete for the PCC pile could increase the pile diameter as well as the contact pressure at the pile-soil interface due to the expansion process of concrete, which allows the improved PCC pile to provide higher capacity than the conventional PCC pile. This paper presents a theoretical model for the new improved PCC pile using expansive concrete technique. The model is formulated by assuming the PCC pile installation process as large strain undrained cylindrical cavity expansion and the subsequent pile shaft expansion combined with soil consolidation process is simulated by the small strain cylindrical cavity expansion combined with strain-controlled consolidation. Then, similarity solution technique is used to solve the problem of cavity expansion in modified cam Clay (MCC) model, while the strain-controlled consolidation is calculated through the finite difference method (FDM). Subsequently, the suitability of the cavity expansion solution in the interpretation of the PCC pile installation is verified by comparing the calculated excess pore pressure with the measured value in an instrumented field test. The stress changes and excess pore pressure during the PCC pile installation and subsequent pile shaft expansion are investigated by means of parametric study. The proposed theoretical model first reveals and quantifies the fundamental mechanism of the PCC pile using expansive concrete technique and it provides a theoretical basis for developing design methods of the new improved PCC pile in the future.

Finite dimensional disturbance observer based control for nonlinear parabolic PDE systems via output feedback

This paper considers the problem of finite dimensional disturbance observer based control (DOBC) via output feedback for a class of nonlinear parabolic partial differential equation (PDE) systems. The external disturbance is generated by an exosystem modeled by ordinary differential equations (ODEs), which enters into the PDE system through the control channel. Motivated by the fact that the dominant dynamic behavior of parabolic PDE systems can be characterized by a finite number of degrees of freedom, the modal decomposition technique is initially applied to the PDE system to derive a slow subsystem of finite dimensional ODEs. Subsequently, based on the slow subsystem and the exosystem, a disturbance observer (DO) and a slow mode observer (SMO) are constructed to estimate the disturbance and the slow modes. Moreover, an observation spillover observer (OSO) is also constructed to cancel approximately the effect of the observation spillover. Then, a finite dimensional DOBC design via output feedback is developed to estimate and compensate the disturbance, such that the closed-loop PDE system is exponentially stable in the presence of the disturbance. The condition for the existence of the proposed controller is given in terms of bilinear matrix inequality. Two algorithms based on the linear matrix inequality (LMI) technique are provided for solving control and observer gain matrices of the proposed controller. Finally, the developed design method is applied to the control of a one-dimensional diffusion-reaction process to illustrate its effectiveness.

Effective shear connection for shallow cellular composite floor beams

Shallow cellular composite floor beam is a new type of composite floor beam that usually consists of a structural steel beam with regularly spaced web openings and concrete slab casted above the steel decking. In this study, the shear transferring mechanisms of shallow cellular composite beams design with innovative shear connection systems are investigated. A detailed finite element analysis program was performed to investigate the force transferring mechanism, load bearing capacity and failure behavior of the shear connections under direct longitudinal shear forces by simulating the push-out tests. Four different configurations of shear connections (web opening configurations) were designed and an intensive parametric study was conducted to determine the material and geometric parameters that likely influence the behavior of the shear connection. Finally, the findings from this investigation are incorporated with the bending and push-out test results to develop design methods for this form of shear connection. The failure mechanisms of the shear connection were confirmed, and it was also revealed that this type of shear connection is effectively capable to provide the desired shear resistance and ductile behavior if designed properly.

Sampled-Data Stabilization for Fuzzy Genetic Regulatory Networks with Leakage Delays.

This paper deals with the sampled-data stabilization problem for Takagi-Sugeno (T-S) fuzzy genetic regulatory networks with leakage delays. A novel Lyapunov-Krasovskii functional (LKF) is established by the non-uniform division of the delay intervals with triplex and quadruplex integral terms. Using such LKFs for constant and time-varying delay cases, new stability conditions are obtained in the T-S fuzzy framework. Based on this, a new condition for the sampled-data controller design is proposed using a linear matrix inequality representation. A numerical result is provided to show the effectiveness and potential of the developed design method.

Design method and modeling verification for the uniform air flow distribution in the duct ventilation

Uniform air flow distribution is an important and fundamental issue to miscellaneous equipments. The detailed design method and design principle are presented in this work. The practical application for uniform air flow distribution is conducted according to the employed design method. Finite volume method (FVM) is used to verify the designed validation. The numerical treatment of convection terms in governing equations is based on the quadratic upwind interpolation of convective kinematics (QUICK) scheme. The well-know semi-implicit pressure-linked equation (SIMPLE) algorithm is used to treat the coupling of pressure and velocity fields. It is found that the design method is validated for the uniform air flow distribution. The unbalance rate of air flow distribution is less than 10%. Moreover, the uniform of air flow distribution can be further improved by adding vertical baffles. The developed design method is of great significance to obtain uniform air flow distribution.

Robust [formula omitted] control for T–S fuzzy systems subject to missing measurements with uncertain missing probabilities

In this paper, the robust output feedback H∞ control problem is investigated for a class of uncertain Takagi–Sugeno (T–S) fuzzy systems with missing measurements. In the underlying systems, both system parameters and missing probabilities are assumed to be effected by norm-bounded uncertainties which may reflect the reality more closely. The main purpose of this paper is to design a robust output feedback fuzzy controller such that the closed-loop system is asymptotically mean-square stable, and the disturbance rejection attenuation is constrained to a given level by means of the H∞ performance index. Sufficient conditions are established via intensive analysis for the existence of the output feedback fuzzy controller, and the corresponding solvability conditions for the desired controller gains are derived. An illustrative example is provided to show the effectiveness of the developed design method.

Improvement of convergence behavior for adaptive feed-forward control with initial values design in hard disk drives

This paper introduces an improvement method of convergence behavior for adaptive feed-forward control in hard-disk-drives (HDDs). To increase a data capacity of HDDs, head-positioning-control system must compensate for any disturbances which worsen the positioning accuracy. Especially, it is important to compensate for external disturbances in the head positioning system of 2.5 type HDDs. Previous studies proposed an adaptive feed-forward control method to compensate for the external disturbances. However, the control method have problems with respect to convergence in the adaptive algorithm. To overcome the problems, we have developed design method of initial values for the adaptive feed-forward control by using data-driven design method. The initial values designed by proposed method can improve the convergence behavior for the adaptive algorithm.