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The purpose of this paper is the presentation of a technique to be integrated in a numerical airfoil optimization scheme, for the exact satisfaction of a strict equality cross-sectional area constraint.

An airfoil optimization framework is presented, based on Area-Preserving Free-Form Deformation (AP FFD) technique. A parallel metamodel-assisted differential evolution (DE) algorithm is used as an optimizer. In each generation of the DE algorithm, before the evaluation of the fitness function, AP FFD is applied to each candidate solution, via coupling a classic B-Spline-based FFD with an area correction step. The area correction step is achieved by solving a sub problem, which consists of computing and applying the minimum possible offset to each one of the free-to-move control points of the FFD lattice, subject to the area preservation constraint.

The proposed methodology is able to obtain better values of the objective function, compared to both a classic penalty function approach and a generic framework for handling constraints, which suggests the separation of constraints and objectives (separation-sub-swarm), without any loss of the convergence capabilities of the DE algorithm, while it also guarantees an exact area preservation. Due to the linearity of the area constraint in each axis, the extraction of an inexpensive closed-form solution to the sub problem is possible by using the method of Lagrange multipliers.

AP FFD can be easily incorporated into any 2D shape optimization/design process, as it is a time-saving and easy-to-implement repair algorithm, independent from the nature of the problem at hand.

The proposed methodology proved to be an efficient tool in facing airfoil design problems, enhancing the rigidity of the optimal airfoil by preserving its cross-sectional area to a predefined value.

A methodology for designing and printing three-dimensional (3D) objects with specified printing-direction using fused deposition modeling (FDM), which was proposed by a previous paper, enables the expression of natural directions, such as hair, fabric or other directed textures, in modeled objects. This paper aims to enhance this methodology for creating various shapes of generative visual objects with several specialized attributes.

The proposed enhancement consists of two new methods and a new technique. The first is a method for “deformation”. It enables deforming simple 3D models to create varieties of shapes much more easily in generative design processes. The second is the spiral/helical printing method. The print direction (filament direction) of each part of a printed object is made consistent by this method, and it also enables seamless printing results and enables low-angle overhang. The third, i.e. the light-reflection control technique, controls the properties of filament while printing with transparent polylactic acid. It enables the printed objects to reflect light brilliantly.

The proposed methods and technique were implemented in a Python library and evaluated by printing various shapes, and it is confirmed that they work well, and objects with attractive attributes, such as the brilliance, can be created.

The methods and technique proposed in this paper are not well-suited to industrial prototyping or manufacturing that require strength or intensity.

The techniques proposed in this paper are suited for generatively producing various a small number of products with artistic or visual properties.

This paper proposes a completely different methodology for 3D printing than the conventional computer-aided design (CAD)-based methodology and enables products that cannot be created by conventional methods.

The aim of this paper is to explore a method of predicting the amount of personalized bra cup dart in the 3D virtual environment for supporting the made‐to‐measure research of the optimum fitted brassiere pattern design.

Very useful enhanced FFD (free‐form‐deformation) techniques used in both computer animation and geometric modeling were skillfully transplanted to the female breast model deformation. Meanwhile, on the basis of 3D scan and surface modeling technologies, the realization approach of the abstract female breast model library focusing on the individual variations of shapes and sizes was presented. Then according to the principle of isometric area and flabellate segments, the personalized bra cup dart quantity and its distributive information were provided by 3D‐2D transformation.

The paper finds that personalized female breast shapes and various aesthetic breast forms sculpted by different bras could be interactively simulated. Accordingly, the amount of corresponding individual bra cup dart and its distributive information were provided. The cup darts were mainly distributed below the bust line. Moreover, dart shapes were curvy.

The principles of virtual breast library construction and 3D‐2D transformation are also suitable for other parts of the human body such as buttocks, abdomen and, etc. for intimate apparel research.

The method of predicting the personalized bra cup dart quantity based on the 3D virtual breast model library was delivered for the first time. The novel findings provided an important guideline for designers to improve the well‐fitted bra pattern design technique. Furthermore, it would reduce the manufacturing cost without keeping physical dummies.

The purpose of this paper is to illustrate the generation of basic garment pattern using three‐dimensional body measurement data.

A pre‐defined garment model is deformed using free‐form deformation method and the model is flattened to generate flat patterns.

The paper finds that individual basic garment patterns are automatically generated and verified to be well fit on human subjects.

The current approach is to focus on the generation of basic bodice patterns; however, other patterns can also be generated by this method by preparing more garment models.

This method can reduce the time required to design basic patterns as well as enhance their fitness.

The automatic generation of individually fitted garment pattern is one of the most important steps in future garment production process.

Focuses on the development and testing of software for reading and formatting digitized data and exporting it to rapid prototyping (RP). Research and development over two years has involved the implementation of special computer‐aided sculpting software that runs on UNIX workstations and which imports 3D polygonal mesh data in STL, OBJ and DXF formats, then re‐shapes it, much like the pushing and pulling on the surface of a rubber membrane. Specifying a wall thickness gives the model volume, prior to exporting an STL file. Describes how data has been imported form laser digitizing systems, had its shape changed and then how RP parts have been created from the model data.

The purpose of this paper is to develop a software can generate helmet mold from three-dimensional (3D) human body scan data.

An algorithm has been developed to divide data into arbitrary number of groups considering the width, length and height of head using the standard normal distribution theory. A basic helmet mold is generated automatically based on the shape of representative convex hull for each group.

It is possible to analyze the 3D human body scan data of groups with various characteristics and apply them to mass customized production of helmet.

This methodology can be applied for designing other products related to the head shape such as goggles and masks by varying the measurement items of the head.

This methodology will enable mass customized production centered on consumers in the production and design of various equipment and goods to be worn on the head.

An algorithm has been developed to define the vertex point, which is the limit of scan data, for the analysis of 3D human body scan data scan data. In addition, a system was developed that can mass-produce customized products by effectively dividing groups while taking into account the physical characteristics of consumers.

The purpose of this paper is to develop a system to design a bulletproof pad for chest protection using three-dimensional body scan data.

Body data were divided into arbitrary number of groups based on the standard normal distribution theory, considering the width and height of the upper body. Several parameters were used to define the cover area of the bulletproof pad, and the shape of this area of each model in a group was averaged to generate the standard bulletproof pad model for that group.

It is possible to use three-dimensional body scan data in the design process of a mass-customized bulletproof pad for chest protection.

It is expected that it would be possible to design not only bulletproof pad but also many kinds of body-related products that need to reflect the shape of body using the methodology developed in this study.

Using this system, the mass customization of special garments and equipment would be possible, which will improve the wearers’ comfort and work efficiency.

Three-dimensional body measurement, parametric definition of cover area and user interface for shape modification developed in this study will facilitate the consumer-oriented product design.

The purpose of this paper is to develop a multi‐purpose body form that could be used to develop different types of garments by putting body skins with ease on the standard body form.

Free form deformation method was used to generate a virtual model upon the basis of the averaged wire frame. The virtual model was made into a real‐life model by a rapid prototyping (RP) process, and then, the standard body form was made by molding the RP. The 3D polygon shell for a body skin got flattened down to 2D patterns and made by a urethane material.

The standard body form developed by using 3D body scan data better represented the characteristics of the body shapes than the previously hand‐made ones. In addition, by standardizing the production of the body form itself, it is now possible to make body forms into the standards and be consistent in their qualities.

This paper presents the methodology of utilizing 3D body scan data in a garment design, which is possible by incorporating advanced 3D modeling technologies and 3D data of a human body in making body forms. For the mass production of a body skin, it is necessary to develop various special materials simulating soft tissues.

The apparel industry can enjoy cost cutting effects by using this multi‐purpose body form. A company does not have to spend money in purchasing different sizes and shapes of body forms, let alone saving the spaces to store them once purchased.

Due to the inability to directly apply an intra-oral image with esthetic restoration to restore tooth shape in the computer-aided design system, this paper aims to propose a method that can use two-dimensional contours obtained from the image for the three-dimensional dental mesh model restoration.

First, intra-oral image and smiling image are taken from the patient, then teeth shapes of the images are designed based on esthetic restoration concepts and the pixel coordinates of the teeth’s contours are converted into the vertex coordinates in the three-dimensional space. Second, the dental mesh model is divided into three parts – active part, passive part and fixed part – based on the teeth’s contours of the mesh model. Third, the vertices from the teeth’s contours of the dental model are matched with ones from the intra-oral image and with the help of matching operation, the target coordinates of each vertex in the active part can be calculated. Finally, the Laplacian-based deformation algorithm and mesh smoothing algorithm are performed.

Benefitting from the proposed method, the dental mesh model with esthetic restoration can be quickly obtained based on the intra-oral image that is the result of doctor-patient communication. Experimental results show that the quality of restoration meets clinical needs, and the typical time cost of the method is approximately one second. So the method is both time-saving and user-friendly.

The method provides the possibility to design personalized dental esthetic restoration solutions rapidly.

The purpose of this review is to comprehensively consider the material properties and processing of additive titanium alloy and provide a new perspective for the robotic grinding and polishing of additive titanium alloy blades to ensure the surface integrity and machining accuracy of the blades.

At present, robot grinding and polishing are mainstream processing methods in blade automatic processing. This review systematically summarizes the processing characteristics and processing methods of additive manufacturing (AM) titanium alloy blades. On the one hand, the unique manufacturing process and thermal effect of AM have created the unique processing characteristics of additive titanium alloy blades. On the other hand, the robot grinding and polishing process needs to incorporate the material removal model into the traditional processing flow according to the processing characteristics of the additive titanium alloy.

Robot belt grinding can solve the processing problem of additive titanium alloy blades. The complex surface of the blade generates a robot grinding trajectory through trajectory planning. The trajectory planning of the robot profoundly affects the machining accuracy and surface quality of the blade. Subsequent research is needed to solve the problems of high machining accuracy of blade profiles, complex surface material removal models and uneven distribution of blade machining allowance. In the process parameters of the robot, the grinding parameters, trajectory planning and error compensation affect the surface quality of the blade through the material removal method, grinding force and grinding temperature. The machining accuracy of the blade surface is affected by robot vibration and stiffness.

This review systematically summarizes the processing characteristics and processing methods of aviation titanium alloy blades manufactured by AM. Combined with the material properties of additive titanium alloy, it provides a new idea for robot grinding and polishing of aviation titanium alloy blades manufactured by AM.