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Adaptive bump inlet can adaptively change the shape of inlet bump surface according to the flight speed of aircraft, ensuring that the inlet has good inlet-engine match performance in a wide speed range. This paper aims to use a composite flexible skin reinforced by shape memory alloy (SMA) fiber as the deformable structure at bump surface to realize the adjustable bump surface of adaptive bump inlet.

According to the deformation and load-bearing requirements of adaptive bump, SMA is applied to the design of adaptive bump inlet due to its characteristic of super-elasticity. A kind of SMA fiber is studied. A composite flexible skin reinforced by SMA is proposed, and its mechanical properties are analyzed. On this basis, an adaptive bump inlet is designed in which the composite flexible skin reinforced by SMA is used as bump surface, and the shape of the bump surface is adjusted by way of pressuring. The design scheme and specific parameters of the adaptive bump are given.

An adaptive bump surface that meets the design requirements of the inlet is designed, which can effectively adjust the inlet throat area with a throat area change rate of 20%.

An adaptive bump inlet with composite flexible skin as a deformable structure at bump surface is designed, and SMA is applied as the reinforcing fiber.

To ensure accurate position and force control of massage robot working on human body with unknown skin characteristics, this study aims to propose a novel intelligent impedance control system.

First, a skin dynamic model (SDM) is introduced to describe force-deformation on the human body as feed-forward for force control. Then a particle swarm optimization (PSO) method combined with graph-based knowledge transfer learning (GKT) is studied, which will effectively identify personalized skin parameters. Finally, a self-tuning impedance control strategy is designed to accommodate uncertainty of skin dynamics, system delay and signal noise exist in practical applications.

Compared with traditional least square method, genetic algorithm and other kinds of PSO methods, combination of PSO and GKT is validated using experimental data to improve the accuracy and convergence of identification results. The force control is effective, although there are contour errors, control delay and noise problems when the robot does massage on human body.

Integrating GKT into PSO identification algorithm, and designing an adaptive impedance control algorithm. As a result, the robot can understand textural and biological attributes of its surroundings and adapt its planning activities to carry out a stable and accurate force tracking control during dynamic contacts between a robot and a human.

The purpose of this paper is to use numerical methods early in the airframe design process and access the structural performance of wing leading edge devices made of different materials and design details, under bird strike events.

Explicit finite element analysis was used to numerically model bird strike events.

Structural performance charts related to materials and general design details were drawn to explore the design space dictated by the current applicable airworthiness requirements.

This paper makes use of the current capability in the numerical tools available for structural simulations and exposes the existing limitations in the terms of material modelling, material properties and fracture simulation using continuum damage mechanics. Such results will always be in the need of fine-tuning with experimental testing, yet the tools can shed some light very early in the design process in a relative inexpensive manner, especially for design details down selection like materials to use, structural thicknesses and even design arrangements.

Bird strike simulations have been successfully used on aircraft design, mainly at the manufactured articles design validation, testing and certification. This paper presents a hypothetical early design case study of leading edge devices for appropriate material and skin thickness down selection.

Wearables are gaining prominence in the health-care industry and their use is growing. The elderly and other patients can use these wearables to monitor their vitals at home and have them sent to their doctors for feedback. Many studies are being conducted to improve wearable health-care monitoring systems to obtain clinically relevant diagnoses. The accuracy of this system is limited by several challenges, such as motion artifacts (MA), power line interference, false detection and acquiring vitals using dry electrodes. This paper aims to focus on wearable health-care monitoring systems in the literature and provides the effect of MA on the wearable system. Also presents the problems faced while tracking the vitals of users.

MA is a major concern and certainly needs to be suppressed. An analysis of the causes and effects of MA on wearable monitoring systems is conducted. Also, a study from the literature on motion artifact detection and reduction is carried out and presented here. The benefits of a machine learning algorithm in a wearable monitoring system are also presented. Finally, distinct applications of the wearable monitoring system have been explored.

According to the study reduction of MA and multiple sensor data fusion increases the accuracy of wearable monitoring systems.

This study also presents the outlines of design modification of dry/non-contact electrodes to minimize the MA. Also, discussed few approaches to design an efficient wearable health-care monitoring system.

The current corrosion maintenance philosophy reflected in aviation regulations and recommended practices does not stimulate progress in corrosion related technology. A US Air Force (USAF)‐sponsored survey has recommended re‐examination of corrosion maintenance policies and practices to identify lower cost alternatives, and has encouraged research into tools and techniques that reduce maintenance costs while preserving safety. In particular, these include models to predict the impact of existing corrosion damage on structural integrity, methods of predicting corrosion growth rates and nondestructive inspection systems capable of providing corrosion metrics. The Institute for Aerospace Research of the National Research Council Canada (IAR/NRC) has pioneered work on the application of enhanced visual methods for corrosion detection in lap joints and the assessment of the impact of corrosion on lap‐joint structural integrity. The role of these enhanced visual methods in the new corrosion management is described.

The seams of slim fit outdoor pants can be uncomfortable or even restrict body movement. To reduce discomfort, the authors need to determine optimal cutting lines in various designs that do not interfere with body movement. The purpose of this paper is to apply skin deformation mapping during movement to the ergonomic design of outdoor pants, focusing in particular on the 2D pattern generation of the crotch area in a 3D shape during movement.

A 3D shape and skin length deformation of the lower body were observed, including the crotch area, which is difficult to examine on the human body. To design ergonomic and streamlined outdoor pants, the authors selected seam lines where the changes in skin deformation are at their minimum based on the skin deformation mapping. In addition, the inseam along the medial thigh close to the crotch was removed to adjust the skin length of these areas, thereby increasing the extensible area of fabric necessary to adjust to a skin deformation. After selecting the seam lines, each of the 3D pattern blocks was generated by means of a 2D flattening method. In addition, the stress distribution of overlapped replica blocks along the crotch line during the 2D flattening process is a main independent factor to avoid deteriorating lower body movement as well as a good appearance.

Based on the results of skin deformation mapping of a human subject, this study suggested that it is best that the design line crosses where there is no skin deformation possible. And the pants were developed without the inner seam line at the upper medial thigh because of skin deformation of a large range of ±6 percent in the upper medial thigh during a 90° knee flexion or in the squatting down position. In a wear test, the developed 3D pattern without an inseam was rated higher than that with an inseam. This verified that removing the inseam, to prevent skin deformation of the medial upper thigh during knee flexion and squatting, is a logical decision. Regarding the correction of the overlapping area during arrangement of the replica, the appearance of the front of the pants was improved when 80 percent of the overlapping area was distributed near the point of the error source, which is the front of the male’s crotch line.

In this study, the crotch area, which has been difficult to observe in previous studies, were observed thoroughly and it was found that the length of the crotch curve did not increase during movement. In addition, skin deformation was mapped during a 90° knee flexion or in the squatting down position. It is expected that the overall process of developing 3D streamlined outdoor pants from 3D skin deformation mapping can be expanded to the development of patterns for other customized functional pants.

The purpose of this paper is to describe the pre‐design and sizing of a smart leading edge section which is developed in the project SADE (Smart High Lift Devices for Next Generation Wings), which is part of the seventh framework program of the EU.

The development of morphing technologies in SADE concentrates on the leading and trailing edge high‐lift devices. At the leading edge a smart gap and step‐less droop nose device is developed. For the landing flap a smart trailing edge of the flap is in the focus of the research activities. The main path in SADE follows the development of the leading edge section and the subsequent wind tunnel testing of a five meter span full‐scale section with a chord length of three meters in the wind tunnel T‐101 at the Russian central aero‐hydrodynamic institute (TsAGI) in Moscow.

The presented paper gives an overview over the desired performance and requirements of a smart leading edge device, its aerodynamic design for the wind tunnel tests and the structural pre‐design and sizing of the full‐scale leading edge section which will be tested in the wind tunnel.

SADE aims at a major step forward in the development and evaluation of the potential of morphing airframe technologies.

This paper aims to propose a framework for optimizing the pose in the assembly process of the non-ideal parts considering the manufacturing deviations and contact deformations. Furthermore, the accuracy of the method would be verified by comparing it with the other conventional methods for calculating the optimal assembly pose.

First, the surface morphology of the parts with manufacturing deviations would be modeled to obtain the skin model shapes that can characterize the specific geometric features of the part. The model can provide the basis for the subsequent contact deformation analysis. Second, the simulated non-nominal components are discretized into point cloud data, and the spatial position of the feature points is corrected. Furthermore, the evaluation index to measure the assembly quality has been established, which integrates the contact deformations and the spatial relationship of the non-nominal parts’ key feature points. Third, the improved particle swarm optimization (PSO) algorithm combined with the finite element method is applied to the process of solving the optimal pose of the assembly, and further deformation calculations are conducted based on interference detection. Finally, the feasibility of the optimal pose prediction method is verified by a case.

The proposed method has been well suited to solve the problem of the assembly process for the non-ideal parts with complex geometric deviations. It can obtain the reasonable assembly optimal pose considering the constraints of the surface morphological features and contact deformations. This paper has verified the effectiveness of the method with an example of the shaft-hole assembly.

The method proposed in this paper has been well suited to the problem of the assembly process for the non-ideal parts with complex geometric deviations. It can obtain the reasonable assembly optimal pose considering the constraints of the surface morphological features and contact deformations. This paper has verified the method with an example of the shaft-hole assembly.

The different surface morphology influenced by manufacturing deviations will lead to the various contact behaviors of the mating surfaces. The assembly problem for the components with complex geometry is usually accompanied by deformation due to the loading during the contact process, which may further affect the accuracy of the assembly. Traditional approaches often use worst-case methods such as tolerance offsets to analyze and optimize the assembly pose. In this paper, it is able to characterize the specific parts in detail by introducing the skin model shapes represented with the point cloud data. The dynamic changes in the parts' contact during the fitting process are also considered. Using the PSO method that takes into account the contact deformations improve the accuracy by 60.7% over the original method that uses geometric alignment alone. Moreover, it can optimize the range control of the contact to the maximum extent to prevent excessive deformations.

The purpose of this paper is to set up a new framework to enable direct modifications of volume meshes enriched with semantic information associated to multiple partitions. An instance of filleting operator is prototyped under this framework and presented in the paper.

In this paper, a generic mesh modification operator has been designed and a new instance of this operator for filleting finite element (FE) sharp edges of tetrahedral multi-partitioned meshes is also pro-posed. The filleting operator works in two main steps. The outer skin of the tetrahedral mesh is first deformed to round user-specified sharp edges while satisfying constraints relative to the shape of the so-called Virtual Group Boundaries. Then, in the filleting area, the positions of the inner nodes are relaxed to improve the aspect ratio of the mesh elements.

The classical mainstream methodology for product behaviour optimization involves the repetition of four steps: CAD modelling, meshing of CAD models, enrichment of models with FE simulation semantics and FEA. This paper highlights how this methodology could be simplified by two steps: simulation model modification and FEA. The authors set up a new framework to enable direct modifications of volume meshes enriched with semantic information associated to multiple partitions and the corresponding fillet operator is devised.

The proposed framework shows only a paradigm of direct modifications of semantic enriched meshes. It could be further more improved by adding or changing the modules inside. The fillet operator does not take into account the exact radius imposed by user. With this proposed fillet operator the mesh element density may not be enough high to obtain wished smoothness.

This paper fulfils an identified industry need to speed up the product behaviour analysis process by directly modifying the simulation semantic enriched meshes.

The purpose of this paper is to propose a new model for optimizing pre-joining processes quickly and accurately, guiding workers to standardized operations. For the automatic riveting in panel assemblies, the traditional approach of determination of pre-joining processes entirely rests on the experience of workers, which leads to the improper number, location and sequence of pre-joining, the low quality stability and the high repair rate in most cases.

The clearances computation with the complete finite element model for every process combination is time-consuming. Therefore a fast pre-joining processes optimization model (FPPOM) is proposed. This model treats both the measured initial clearances and the stiffness matrices of key points of panels as an input; considers the permissive clearances as an evaluation criterion; regards the optimal number, location and sequence as an objective; and takes the neighborhood-search-based adaptive genetic algorithm as a solution.

A comparison between the FPPOM and complete finite element model with clearances (CFEMC) was made in practice. Further, the results indicate that running the FPPOM is time-saving by >90 per cent compared with the CFEMC.

This paper provides practical insights into realizing the pre-joining processes optimization quickly.

This paper is the first to propose the FPPOM, which could simplify the processes, reduce the degrees of freedom of nodes and conduct the manufacturers to standardized manipulations.