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The purpose of this paper is to focus on solving a fit problem associated with female pants by taking into account the body shape of crotch curves. The patterns of customized pants could be altered with the distance ease (DE) distribution along the crotch curve.

Four pairs of pants with different crotch ease allowances were designed based on a standard mannequin, and used to study how the DE was distributed along the crotch curve at a given ease allowance. The unclothed mannequin and the four pants, which were dressed, respectively, on the mannequin, were scanned consecutively by a body imaging system. The crotch curve of the unclothed mannequin was superimposed on that of each clothed mannequin to exhibit the differences in radial distance so that the DE distribution could be measured.

Through the regression analysis, the prediction models were established to express the relationships between the DE and the ease allowance. These models could be used to estimate the DEs along a crotch curve to reflect its asymmetrical shape when a total allowance was selected. The crotch curves on the pant patterns could be then modified by adding the predicted DEs to the scanned crotch curve.

This study demonstrated a new pattern alteration approach to achieve a better fit for customized female pants based on the 3D scanning data. This approach can be extended to pattern alterations for men’s pants and other shape-critical products.

A MEMS process is described to control diaphragm thickness with an integrated provision for back to front alignment in the fabrication of a polysilicon piezoresistive pressure sensor. The end point detection for the diaphragm etching is suitably incorporated in the process so that it is also used for the back‐to‐front alignment. The proposed process is cost‐effective and suitable for the batch fabrication of the pressure sensor.

The purpose of this research is to study the performance of piezoresistive pressure sensors using polysilicon as the piezoresistive material, which is typically used to measure pressure in high-temperature environments.

The performance of this sensor is enhanced by studying the influence of multi-turn configuration at which the piezoresistors are arranged. Different configurations are studied and compared by laying down their analytical solution.

The validation of analytical results is accomplished through finite element analysis using the software COMSOL Multiphysics. The best configuration, which uses a partial triple-turn configuration, was able to achieve a sensitivity of 116.00 mV/V/MPa over a simulated pressure range of 0 to 500 KPa.

The literature shows the study of single-turn and double-turn meander-shaped configuration of micro-electromechanical systems piezoresistive pressure sensor but multi-turn meander-shaped configuration using a square silicon diaphragm has not been reported. Its study has reflected promising results than its counterparts based on key performance parameters such as sensitivity and linearity and are more effective to be used for automotive, aviation, biomedical and consumer electronics applications.

Structures play a very important role in developing pressure sensors with good sensitivity and linearity, as they undergo deformation to the input pressure and function as the primary sensing element of the sensor. To achieve high sensitivity, thinner diaphragms are required; however, excessively thin diaphragms may induce large deflection and instability, leading to the unfavorable performances of a sensor in terms of linearity and repeatability. Thereby, importance is given to the development of innovative structures that offer good linearity and sensitivity. This paper aims to investigate the sensitivity of a bossed diaphragm coupled fixed guided beam three-dimensional (3D) structure for pressure sensor applications.

The proposed sensor comprises of mainly two sensing elements: the first being the 3D mechanical structure made of bulk silicon consisting of boss square diaphragm along with a fixed guided beam landing on to its center, forming the primary sensing element, and the diffused piezoresistors, which form the secondary sensing element, are embedded in the tensile and compression regions of the fixed guided beam. This micro mechanical 3 D structure is packaged for applying input pressure to the bottom of boss diaphragm. The sensor without pressure load has no deflection of the diaphragm; hence, no strain is observed on the fixed guided beam and also there is no change in the output voltage. When an input pressure P is applied through the pressure port, there is a deformation in the diaphragm causing a deflection, which displaces the mass and the fixed guided beam vertically, causing strain on the fixed guided beam, with tensile strain toward the guided end and compressive strain toward the fixed end of the close magnitudes. The geometrical dimensions of the structure, such as the diaphragm, boss and fixed guided beam, are optimized for linearity and maximum strain for an applied input pressure range of 0 to 10 bar. The structure is also analyzed analytically, numerically and experimentally, and the results are compared.

The structure offers equal magnitudes of tensile and compressive stresses on the surface of the fixed guided beam. It also offers good linearity and sensitivity. The analytical, simulation and experimental studies of this sensor are introduced and the results correlate with each other. Customized process steps are followed wherein two silicon-on-insulator (SOI) wafers are fusion bonded together, with SOI-1 wafer used to realize the diaphragm along with the boss and SOI-2 wafer to realize the fixed guided beam, leading to formation of a 3D structure. The geometrical dimensions of the structure, such as the diaphragm, boss and fixed guided beam, are optimized for linearity and maximum strain for an applied input pressure range of 0 to10 bar.

This paper presents a unique and compact 3D micro-mechanical structure pressure sensor with a rigid center square diaphragm (boss diaphragm) and a fixed guided beam landing at its center, with diffused piezoresistors embedded in the tensile and compression regions of the fixed guided beam. A total of six masks were involved to realize and fabricate the 3D structure and the sensor, which is presumed to be the first of its kind in the fabrication of MEMS-based piezoresistive pressure sensor.

Pressure, being one of the key variables investigated in scientific and engineering research, requires critical and accurate measurement techniques. With the advancements in materials and machining technologies, there is a large leap in the measurement techniques including the development of micro electromechanical systems (MEMS) sensors. These sensors are one to two orders smaller in magnitude than traditional sensors and combine electrical and mechanical components that are fabricated using integrated circuit batch-processing technologies. MEMS are finding enormous applications in many industrial fields ranging from medical to automotive, communication to electronics, chemical to aviation and many more with a potential market of billions of dollars. MEMS pressure sensors are now widely used devices owing to their intrinsic properties of small size, light weight, low cost, ease of batch fabrication and integration with an electronic circuit. This paper aims to identify and analyze the common pressure sensing techniques and discuss their uses and advantages. As per our understanding, usage of MEMS pressure sensors in the aerospace industry is quite limited due to cost constraints and indirect measurement approaches owing to the inability to locate sensors in harsh environments. The purpose of this study is to summarize the published literature for application of MEMS pressure sensors in the said field. Five broad application areas have been investigated including: propulsion/turbomachinery applications, turbulent flow diagnosis, experimentalaerodynamics, micro-flow control and unmanned aerial vehicle (UAV)/micro aerial vehicle (MAV) applications.

The first part of the paper deals with an introduction to MEMS pressure sensors and mathematical relations for its fabrication. The second part covers pressure sensing principles followed by the application of MEMS pressure sensors in five major fields of aerospace industry.

In this paper, various pressure sensing principles in MEMS and applications of MEMS technology in the aerospace industry have been reviewed. Five application fields have been investigated including: Propulsion/Turbomachinery applications, turbulent flow diagnosis, experimental aerodynamics, micro-flow control and UAV/MAV applications. Applications of MEMS sensors in the aerospace industry are quite limited due to requirements of very high accuracy, high reliability and harsh environment survivability. However, the potential for growth of this technology is foreseen due to inherent features of MEMS sensors’ being light weight, low cost, ease of batch fabrication and capability of integration with electric circuits. All these advantages are very relevant to the aerospace industry. This work is an endeavor to present a comprehensive review of such MEMS pressure sensors, which are used in the aerospace industry and have been reported in recent literature.

As per the author’s understanding, usage of MEMS pressure sensors in the aerospace industry is quite limited due to cost constraints and indirect measurement approaches owing to the inability to locate sensors in harsh environments. Present work is a prime effort in summarizing the published literature for application of MEMS pressure sensors in the said field. Five broad application areas have been investigated including: propulsion/turbomachinery applications, turbulent flow diagnosis, experimental aerodynamics, micro-flow control and UAV/MAV applications.

To fabricate submicrometer thin membrane of silicon nitride and silicon dioxide over an anisotropically etched cavity in (100) silicon.

PECVD of silicon dioxide and Silcion nitride layers of compatible thicknesses followed by thermal annealing in nitrogen ambients at 1,000°C for 30 min, leads to stable membrane formation. Anisotropic etching of (100) silicon below the membrane through channels on the sides has been used with controlled cavity dimensions.

Lateral front side etching through channels slows down etching rate drastically. The etching mechanism has been discussed with experimental details.

Vacuum sealed cavity membranes can be realised for micro sensor applications.

The process is new and feasible for micro sensor technologies.

This study aimed to clarify the criteria for subjective evaluation of the similarities and differences between virtual and actual pants and propose a quantitative evaluation method for those similarities and differences based on geometric features related to the evaluation.

Using patterns, we made five pairs of actual pants for a dummy in five fabrics. We simulated virtual pants with a 3-D simulator. Sensory evaluation was conducted with images of the virtual and actual pants: 20 participants compared the images based on a questionnaire. For the structure of evaluation, the authors undertook analysis of variance and principal component analysis. The actual and virtual pants were geometrically compared using the 3-D scanned data. To investigate the relationship between quantitative and sensory evaluation, the authors calculated the correlation coefficients.

The authors found that subjects perceived the differences between actual and simulated pants. When comparing the virtual and actual pants, the criteria for the differences were the silhouette from the front view, hem width, waist and wrinkles. Using differences in the hem width, it would be possible to evaluate the differences between actual and simulated pants. Roughness and smoothness of the silhouette also affected evaluation.

The authors clarified the evaluation criteria for the similarities and differences between virtual and actual pants. The authors proposed a quantitative evaluation method for the similarities and differences between virtual and actual garment based on our criteria. This study will be of benefit to 3-D simulator users and developers.

The purpose of this paper is to present a selective wet‐etching method of boron doped low‐pressure chemical vapour deposition (LPCVD) polysilicon film for the realization of piezoresistors over the bulk micromachined diaphragm of (100) silicon with improved yield and uniformity.

The method introduces discretization of the LPCVD polysilicon film using prior etching for the grid thus dividing each chip on the entire wafer. The selective etching of polysilicon for realizing of piezoresistors is limited to each chip area with individual boundaries.

The method provides a uniform etching on the entire silicon wafer irrespective of its size and leads to economize the fabrication process in a batch production environment with improved yield.

The method introduces one extra process step of photolithography and subsequent etching for discretizing the polysilicon film.

The method is useful to enhance yield while defining metal lines for contact purposes on fabricated electronic structures using microelectronics. Stress developed in LPCVD polysilicon can be removed using proposed approach of discretization of polysilicon film.

The work is an outcome of regular fabrication work using conventional approaches in an R&D environment. The proposed method replaces the costly reactive ion etching techniques with stable reproducibility and ease in its implementation.

The purpose of this paper is to show that a new size labelling system based on the data gathered by [TC]² in the Size USA, Let's Size up America survey would better serve the female population than the system currently in use.

Based on previous research conducted on [TC]² data and on pants measurements in the Canadian market, a new labelling system is proposed where size information is provided with three specific body measurements along with a female silhouette pictogram.

The paper demonstrates that a size label showing three pants measurements: pants waist, approximate hips, and inseam length, accompanied by a silhouette identifying where these measures were taken, is highly predictive of fit.

The study was limited to lower body (pants) for female.

A change to such a size‐labelling system would allow the apparel industry to move towards mass customisation at minimal costs. It would be more effective for the apparel order givers and retailers, enabling them to target whichever market they wish yet convey the necessary fit information in a generally accepted format. This system would also be more efficient as it would reduce the consumer time spent in fit identification and merchandise returns, in the case of internet or catalogue sales. As a corollary, it would increase both consumer shopping experience satisfaction and industry profitability.

The study proposes a new labelling system.

The purpose of this paper is to propose an interactive 2D–3D garment parametric pattern-making and linkage editing scheme that integrates clothing design, simulation and interaction to design 3D garments and 2D patterns. The proposed scheme has the potential to satisfy the individual needs of fashion industry, such as precise fit evaluation of the garment, interactive style editing with ease allowance and constrained contour lines in fashion design.

The authors first construct a parametric pattern-making model for flat pattern design corresponding to the body dimensions. Then, the designing 2D patterns are stitched on a virtual 3D mannequin by performing a virtual try-on. If the customer is unsatisfied after the virtual try-on, the adjustable parameters (appearance parameters and fit parameters) can be adjusted using the 2D–3D linkage editing with hierarchical constrained contour lines, and the fit evaluation tool interactively provides the feedback.

The authors observed that the usability and efficiency of the existing garment pattern-making method simplifies the garment pattern-making process. The authors utilize an interactive garment parametric flat pattern-making model to generate an individualized garment flat pattern that effectively adjust and realize the local editing of the garment pattern-making. The 2D–3D linkage editing is then employed, which alters the size and shape of garment pattern for a precise human model fit of the 3D garment using hierarchical constrained contour lines. Various instances have validated the effectiveness of the proposed scheme, which can increase the reusability of the existing garment styles and improve the efficiency of fashion design.

First, the authors do not consider the garment pattern-making design of sophisticated styles. Second, the authors do not directly consider complex garment shapes such as wrinkles, folds, multi-layer models and fabric physical properties.

The authors propose a pattern adjustment scheme that uses the 3D virtual try-on technology to avoid repetitions of reality-based fit tests and garment sample making in the designing process of clothing products. The proposed scheme provides interactive selections of garment patterns and sizes and renders modification tools for 3D garment designing and 2D garment pattern-making. The authors present the 2D–3D interactive linkage editing scheme for a custom-fit garment pattern based on the hierarchical constraint contour lines. The spatial relationship among the human body, pattern pieces and 3D garment model is adequately expressed, and the final design result of the garment pattern is obtained by constraint solving. Meanwhile, the tightness tension of different parts of the 3D garment is analyzed, and the fit and comfort of the garment are quantitatively evaluated.