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Article
Publication date: 9 August 2021

Lijun Chao, Zhi Xiong, Jianye Liu, Chuang Yang and Yudi Chen

To solve problems of low intelligence and poor robustness of traditional navigation systems, the purpose of this paper is to propose a brain-inspired localization method of the…

Abstract

Purpose

To solve problems of low intelligence and poor robustness of traditional navigation systems, the purpose of this paper is to propose a brain-inspired localization method of the unmanned aerial vehicle (UAV).

Design/methodology/approach

First, the yaw angle of the UAV is obtained by modeling head direction cells with one-dimension continuous attractor neural network (1 D-CANN) and then inputs into 3D grid cells. After that, the motion information of the UAV is encoded as the firing of 3 D grid cells using 3 D-CANN. Finally, the current position of the UAV can be decoded from the neuron firing through the period-adic method.

Findings

Simulation results suggest that continuous yaw and position information can be generated from the conjunctive model of head direction cells and grid cells.

Originality/value

The proposed period-adic cell decoding method can provide a UAV with the 3 D position, which is more intelligent and robust than traditional navigation methods.

Details

Aircraft Engineering and Aerospace Technology, vol. 93 no. 7
Type: Research Article
ISSN: 1748-8842

Keywords

Article
Publication date: 1 June 2012

Jin Sun, Xiaobo Chen, Xiaoyong Lu and Juntong Xi

The purpose of this paper is to describe a processing system for 3D dress geometry modelling and texture mapping.

Abstract

Purpose

The purpose of this paper is to describe a processing system for 3D dress geometry modelling and texture mapping.

Design/methodology/approach

Since the range image and its corresponding texture from one direction could be acquired by areal 3D scanner simultaneously, the texture can be integrated into the range image exactly. In the geometry modelling stage, the graph‐based algorithm is used for multi‐view registration. In order to enhance its robustness, a method for judging bad pairwise registration is proposed based on the computation of two views' overlapping percentage. In order to enrich its completeness, combined the graph analysis with the metaview method is used to deal with the measurement data for local details. In the texture mapping stage, based on grid search structure, the method of solving the Poisson equation for the colour field that best fits the colour gradients can produce a seamlessly textured surface quickly.

Findings

Results show that the processing system can provide a 3D textured dress geometry model with no seams and low distortion successfully.

Practical implications

The processing system can provide an accurate 3D dress geometry model, which can be used to modify the further design or virtual try.

Originality/value

A 3D dress geometry model with no seams and low distortion provides the fashion designer with not only the visual effects, but also accurate data used for design modification.

Details

International Journal of Clothing Science and Technology, vol. 24 no. 2/3
Type: Research Article
ISSN: 0955-6222

Keywords

Article
Publication date: 18 April 2016

Valery Gitis, Alexander Derendyaev and Arkady Weinstock

This paper aims to describe two Web-based technologies of geographic information systems (GIS) to be used in monitoring and analysis of environmental processes, proposed by the…

Abstract

Purpose

This paper aims to describe two Web-based technologies of geographic information systems (GIS) to be used in monitoring and analysis of environmental processes, proposed by the authors. The technologies analyze the temporal aspect of the process together with the spatial aspect, which defers them from most other works on environmental processes, as these are usually limited either to spatial statistics or to temporal statistics. The approach is instrumental in dynamically finding the relationships between the processes and predicting critical incidents.

Design/methodology/approach

Often, the study of natural processes is limited to the analysis of their spatial properties presented by individual time series. The principal idea of this approach consists in supplementing this traditional analysis with the analysis of time fields. In this way, the authors are able to analyze temporal and spatial properties of environmental processes together.

Findings

The paper presents two technologies which provide the analysis of spatial and temporal data obtained in natural environment monitoring. The discussed spatio-temporal data mining methods are shown to enable the research into environmental processes, and the solution of practical issues of critical situation forecasts.

Originality/value

The paper discussed Web-based GIS technologies for the analysis of the temporal aspect of the environmental process together with the spatial aspect. Application examples demonstrate the ability of this approach to find the relationships in dynamics of the processes and to predict critical incidents.

Details

International Journal of Web Information Systems, vol. 12 no. 1
Type: Research Article
ISSN: 1744-0084

Keywords

Article
Publication date: 9 February 2018

Qiang Zhou, Danping Zou and Peilin Liu

This paper aims to develop an obstacle avoidance system for a multi-rotor micro aerial vehicle (MAV) that flies in indoor environments which usually contain transparent…

Abstract

Purpose

This paper aims to develop an obstacle avoidance system for a multi-rotor micro aerial vehicle (MAV) that flies in indoor environments which usually contain transparent, texture-less or moving objects.

Design/methodology/approach

The system adopts a combination of a stereo camera and an ultrasonic sensor to detect obstacles and extracts three-dimensional (3D) point clouds. The obstacle map is built on a coarse global map and updated by local maps generated by the recent 3D point clouds. An efficient layered A* path planning algorithm is also proposed to address the path planning in 3D space for MAVs.

Findings

The authors conducted a lot of experiments in both static and dynamic scenes. The results show that the obstacle avoidance system works reliably even when transparent or texture-less obstacles are present. The layered A* path planning algorithm is much faster than the traditional 3D algorithm and makes the system response quickly when the obstacle map has been changed because of the moving objects.

Research limitations/implications

The limited field of view of both stereo camera and ultrasonic sensor makes the system need to change heading first before moving side to side or moving backward. But this problem could be addressed when multiple systems are mounted toward different directions on the MAV.

Practical implications

The developed approach could be valuable to applications in indoors.

Originality/value

This paper presents a robust obstacle avoidance system and a fast layered path planning algorithm that are easy to be implemented for practical systems.

Details

Industrial Robot: An International Journal, vol. 45 no. 2
Type: Research Article
ISSN: 0143-991X

Keywords

Article
Publication date: 18 April 2016

Yunlong Tang and Yaoyao Fiona Zhao

This paper aims to provide a comprehensive review of the state-of–the-art design methods for additive manufacturing (AM) technologies to improve functional performance.

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Abstract

Purpose

This paper aims to provide a comprehensive review of the state-of–the-art design methods for additive manufacturing (AM) technologies to improve functional performance.

Design/methodology/approach

In this survey, design methods for AM to improve functional performance are divided into two main groups. They are design methods for a specific objective and general design methods. Design methods in the first group primarily focus on the improvement of functional performance, while the second group also takes other important factors such as manufacturability and cost into consideration with a more general framework. Design methods in each groups are carefully reviewed with discussion and comparison.

Findings

The advantages and disadvantages of different design methods for AM are discussed in this paper. Some general issues of existing methods are summarized below: most existing design methods only focus on a single design scale with a single function; few product-level design methods are available for both products’ functionality and assembly; and some existing design methods are hard to implement for the lack of suitable computer-aided design software.

Practical implications

This study is a useful source for designers to select an appropriate design method to take full advantage of AM.

Originality/value

In this survey, a novel classification method is used to categorize existing design methods for AM. Based on this classification method, a comprehensive review is provided in this paper as an informative source for designers and researchers working in this field.

Details

Rapid Prototyping Journal, vol. 22 no. 3
Type: Research Article
ISSN: 1355-2546

Keywords

Article
Publication date: 1 June 2000

A. Savini

Gives introductory remarks about chapter 1 of this group of 31 papers, from ISEF 1999 Proceedings, in the methodologies for field analysis, in the electromagnetic community…

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Abstract

Gives introductory remarks about chapter 1 of this group of 31 papers, from ISEF 1999 Proceedings, in the methodologies for field analysis, in the electromagnetic community. Observes that computer package implementation theory contributes to clarification. Discusses the areas covered by some of the papers ‐ such as artificial intelligence using fuzzy logic. Includes applications such as permanent magnets and looks at eddy current problems. States the finite element method is currently the most popular method used for field computation. Closes by pointing out the amalgam of topics.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 19 no. 2
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 12 September 2008

Marco Gianinetto

Cartosat‐1 is the first Indian Remote Sensing satellite, developed for topographic mapping, able to collect in‐track high‐resolution stereo images with a 2.5 m pixel size. In the…

Abstract

Purpose

Cartosat‐1 is the first Indian Remote Sensing satellite, developed for topographic mapping, able to collect in‐track high‐resolution stereo images with a 2.5 m pixel size. In the framework of the Cartosat‐1 Scientific Assessment Programme (C‐SAP), the Politecnico di Milano University (Italy) evaluated the performances of the Cartosat‐1 satellite in the generation of digital terrain models (DTMs) from stereo‐couples. The purpose of this paper is to describe in detail the outcomes for the Salon de Provence (France) test site, with respect to existing standards and products actually used in France and also to provide a comparison with the global Shuttle Radar Topography Mission's DTM freely available from by NASA.

Design/methodology/approach

The Cartosat‐1 data processing was done using the commercial off‐the‐shelf software ENVI®, selected for investigating the capabilities and limits of the system using standard image processing tools, so from the point of view of a typical remote sensing user. The data processing involved the following aspects: data pre‐processing; optimization of the DTM's extraction procedure; analysis of the influence of ground control points' (GCPs) in the generated DTMs; analysis of the influence of the DTM's resolution in the elevation accuracy; and post‐processing refinement.

Findings

When generating relative DTMs an error was observed in elevation of some hundreds of meters. After georeferencing, the root mean square error (RMSE) was between 9.0 and 14.2 m and the LE90 between 16.1 and 19.0 m. When generating absolute DTMs, the optimum number of GCPs was found to be 9, with a regular geometric distribution (4.6 m RMSE and 6.5 m LE90 for 10 m grid cell size). Post‐processing may be applied to enhance results (1.6 m RMSE and 2.0 m LE90 for 10 m grid cell size). In this case, the absolute DTMs fulfilled and also overcame the standards required for the IGNs and Spot Image's Reference 3D®.

Originality/value

This paper describes the outcomes of the C‐SAP led by the International Society for Photogrammetry and Remote Sensing and the Indian Space Research Organisation for evaluating the capabilities of the last Cartosat‐1 satellite. The aim is to provide remote sensing users a comprehensive study about the potentialities and limits of the Cartosat‐1 images for multi‐resolution DTM generation (from 5 to 90 m grid cell size).

Details

Sensor Review, vol. 28 no. 4
Type: Research Article
ISSN: 0260-2288

Keywords

Article
Publication date: 4 January 2021

Huichao Wang, Qin Lian, Dichen Li, Chenghong Li, Tingze Zhao and Jin Liang

Reconstructing multi-layer tissue structure using cell printing to repairing complex tissue defect is a challenging task, especially using in situ bioprinting. This study aims to…

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Abstract

Purpose

Reconstructing multi-layer tissue structure using cell printing to repairing complex tissue defect is a challenging task, especially using in situ bioprinting. This study aims to propose a method of in situ bioprinting multi-tissue layering and path planning for complex skin and soft tissue defects.

Design/methodology/approach

The scanned three-dimensional (3D) point cloud of the skin and soft tissue defect is taken as the input data, the depth value of the defect is then calculated using a two-step grid division method, and the tissue layer is judged according to the depth value. Then, the surface layering and path planning in the normal direction are performed for different tissue layers to achieve precise tissue layering filling of complex skin soft tissue defects.

Findings

The two-step grid method can accurately calculate the depth of skin and soft tissue defects and judge the tissue layer accordingly. In the in situ bioprinting experiment of the defect model, the defect can be completely closed. The defect can be reconstructed in situ, and the reconstructed structure is basically the same as the original skin tissue structure, proving the feasibility of the proposed method.

Originality/value

This study proposes an in situ bioprinting multi-tissue layering and path planning method for complex skin and soft tissue defects, which can directly convert the scanned 3D point cloud into a multi-tissue in situ bioprinting path. The printed result has a similar structure to that of the original skin tissue, which can make cells or growth factors act on the corresponding tissue layer targets.

Details

Rapid Prototyping Journal, vol. 27 no. 2
Type: Research Article
ISSN: 1355-2546

Keywords

Article
Publication date: 1 February 1987

Ajay Kela, Mukul Saxena and Renato Perucchio

This paper deals initially with a new algorithm for generating automatically, from solid models of mechanical parts, finite element meshes that are organized as spatially…

Abstract

This paper deals initially with a new algorithm for generating automatically, from solid models of mechanical parts, finite element meshes that are organized as spatially addressable quaternary trees (for 2D work) or octal trees (for 3D work). Because such meshes are inherently hierarchical as well as spatially addressable, they permit efficient substructuring techniques to be used for both global analysis and incremental re‐meshing and re‐analysis. The paper summarizes the global and incremental techniques, and presents some results from an experimental closed loop 2D system in which meshing, analysis, error evaluation, and re‐meshing and re‐analysis are done automatically and adaptively. The paper concludes with a progress report on a 3D implementation.

Details

Engineering Computations, vol. 4 no. 2
Type: Research Article
ISSN: 0264-4401

Article
Publication date: 18 July 2020

Arash Shahin, Ashraf Labib, Ali Haj Shirmohammadi and Hadi Balouei Jamkhaneh

The aim of this study is to develop a 3D model of decision- making grid (DMG) considering failure detection rate.

Abstract

Purpose

The aim of this study is to develop a 3D model of decision- making grid (DMG) considering failure detection rate.

Design/methodology/approach

In a comparison between DMG and failure modes and effects analysis (FMEA), severity has been assumed as time to repair and occurrence as the frequency of failure. Detection rate has been added as the third dimension of DMG. Nine months data of 21 equipment of casting unit of Mobarakeh Steel Company (MSC) has been analyzed. Then, appropriate condition monitoring (CM) techniques and maintenance tactics have been suggested. While in 2D DMG, CM is used when downtime is high and frequency is low; its application has been developed for other maintenance tactics in a 3D DMG.

Findings

Findings indicate that the results obtained from the developed DMG are different from conventional grid results, and it is more capable in suggesting maintenance tactics according to the operating conditions of equipment.

Research limitations/implications

In failure detection, the influence of CM techniques is different. In this paper, CM techniques have been suggested based on their maximum influence on failure detection.

Originality/value

In conventional DMG, failure detection rate is not included. The developed 3D DMG provides this advantage by considering a new axis of detection rate in addition to mean time to repair (MTTR) and failure frequency, and it enhances maintenance decision-making by simultaneous selection of suitable maintenance tactics and condition-monitoring techniques.

Details

International Journal of Quality & Reliability Management, vol. 38 no. 2
Type: Research Article
ISSN: 0265-671X

Keywords

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