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Article
Publication date: 13 March 2024

Ziyuan Ma, Huajun Gong and Xinhua Wang

The purpose of this paper is to construct an event-triggered finite-time fault-tolerant formation tracking controller, which can achieve a time-varying formation control for…

Abstract

Purpose

The purpose of this paper is to construct an event-triggered finite-time fault-tolerant formation tracking controller, which can achieve a time-varying formation control for multiple unmanned aerial vehicles (UAVs) during actuator failures and external perturbations.

Design/methodology/approach

First, this study developed the formation tracking protocol for each follower using UAV formation members, defining the tracking inaccuracy of the UAV followers’ location. Subsequently, this study designed the multilayer event-triggered controller based on the backstepping method framework within finite time. Then, considering the actuator failures, and added self-adaptive thought for fault-tolerant control within finite time, the event-triggered closed-loop system is subsequently shown to be a finite-time stable system. Furthermore, the Zeno behavior is analyzed to prevent infinite triggering instances within a finite time. Finally, simulations are conducted with external disturbances and actuator failure conditions to demonstrate formation tracking controller performance.

Findings

It achieves improved performance in the presence of external disturbances and system failures. Combining limited-time adaptive control and event triggering improves system stability, increase robustness to disturbances and calculation efficiency. In addition, the designed formation tracking controller can effectively control the time-varying formation of the leader and followers to complete the task, and by adding a fixed-time observer, it can effectively compensate for external disturbances and improve formation control accuracy.

Originality/value

A formation-following controller is designed, which can handle both external disturbances and internal actuator failures during formation flight, and the proposed method can be applied to a variety of formation control scenarios and does not rely on a specific type of UAV or communication network.

Details

Aircraft Engineering and Aerospace Technology, vol. 96 no. 3
Type: Research Article
ISSN: 1748-8842

Keywords

Article
Publication date: 8 April 2024

Yimei Chen, Yixin Wang, Baoquan Li and Tohru Kamiya

The purpose of this paper is to propose a new velocity prediction navigation algorithm to develop a conflict-free path for robots in dynamic crowded environments. The algorithm…

Abstract

Purpose

The purpose of this paper is to propose a new velocity prediction navigation algorithm to develop a conflict-free path for robots in dynamic crowded environments. The algorithm BP-prediction and reciprocal velocity obstacle (PRVO) combines the BP neural network for velocity PRVO to accomplish dynamic collision avoidance.

Design/methodology/approach

This presented method exhibits innovation by anticipating ahead velocities using BP neural networks to reconstruct the velocity obstacle region; determining the optimized velocity corresponding to the robot’s scalable radius range from the error generated by the non-holonomic robot tracking the desired trajectory; and considering acceleration constraints, determining the set of multi-step reachable velocities of non-holonomic robot in the space of velocity variations.

Findings

The method is validated using three commonly used metrics of collision rate, travel time and average distance in a comparison between simulation experiments including multiple differential drive robots and physical experiments using the Turtkebot3 robot. The experimental results show that our method outperforms other RVO extension methods on the three metrics.

Originality/value

In this paper, the authors propose navigation algorithms capable of adaptively selecting the optimal speed for a multi-robot system to avoid robot collisions during dynamic crowded interactions.

Details

Industrial Robot: the international journal of robotics research and application, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0143-991X

Keywords

Open Access
Article
Publication date: 18 February 2020

Danah Ali Alenezi

This study aims to examine the nexus of the US rebalance strategy to Asia and the US–China rivalry in the South China Sea (SCS) from the perspective of the offensive realism…

10867

Abstract

Purpose

This study aims to examine the nexus of the US rebalance strategy to Asia and the US–China rivalry in the South China Sea (SCS) from the perspective of the offensive realism theory.

Design/methodology/approach

The study depends on the descriptive approach that deals with the analysis and description of the phenomenon. Also, the study uses the qualitative method to analyze the primary sources concerning the rebalance.

Findings

The study has found four results: first, the rebalance strategy to Asia is a comprehensive strategy to contain China’s rise. Second, China’s offensive strategy in the SCS since 2008 has been the main driver of launching the rebalance. Third, offensive realism presents a convenient analysis to understand the rebalance, China’s offensive strategy in the SCS, and the US–China rivalry in the SCS. Forth, SCS is one of the most important venues of the US–China rivalry for global hegemony.

Research limitations/implications

Limited to the period from 2009 to 2016. The Obama Era.

Originality/value

This study highlights the centrality of the SCS in the US–China global rivalry that has not been yet well researched.

Details

Review of Economics and Political Science, vol. 9 no. 2
Type: Research Article
ISSN: 2356-9980

Keywords

Article
Publication date: 5 October 2023

Oke Hendra, Benny Kurnianto and Ika Endrawijaya

This study aimed to develop an adapted collaborative governance model for aviation human resource development in Indonesia's approved training organisations (ATO), considering the…

Abstract

Purpose

This study aimed to develop an adapted collaborative governance model for aviation human resource development in Indonesia's approved training organisations (ATO), considering the expected changes in the industry due to advanced technologies. The model, based on Ansell and Gash's approach, emphasizes multi-stakeholder collaboration to ensure workforce development aligns with industry and regulatory standards and accommodates technological advancements.

Design/methodology/approach

Qualitative methods, such as in-depth interviews and focus group discussions, were employed to collect and analyse data.

Findings

The results indicated that collaborative governance is a valuable tool for cultivating competent human resources and facilitating industry improvement in the face of rapid technological change.

Originality/value

The proposed model contributes significantly to the field by promoting inclusive and effective human resource development through the Centre for Aviation Human Resource Development (CAHRD), thereby preparing the Indonesian aviation industry for the impact of advanced technologies. Furthermore, this study contributes to the enhancement of Ansell and Gash's collaborative governance theoretical framework by effectively addressing its empirical gaps concerning vocational education and training challenges within Indonesia's air transportation sector.

Details

Higher Education, Skills and Work-Based Learning, vol. 14 no. 2
Type: Research Article
ISSN: 2042-3896

Keywords

Article
Publication date: 16 June 2022

Vinícius Barbosa Henrique and Marlene Salete Uberti

The cadaster goes through its fifth wave of updating, seeking agility and efficiency in cadastral registration. However, despite recent advances in remote sensors and the low cost…

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Abstract

Purpose

The cadaster goes through its fifth wave of updating, seeking agility and efficiency in cadastral registration. However, despite recent advances in remote sensors and the low cost of remotely piloted aircraft systems (RPAS), on-site visits are still used to complete the cadastral form. Thus, this work aims to employ techniques and methodologies for remote characterization of buildings for cadastral updating purposes, reducing the need to enter the parcels.

Design/methodology/approach

The research tools used were: RPAS and MMS (mobile mapping systems), making a three-dimensional model with RPAS data, and analyzing the results from these platforms. With the 3D model, it was possible to extract measurements and characteristics.

Findings

The analysis of the 3D model with the aerial photographs obtained better results in the characterization of the buildings and is the most indicated according to the study. There were difficulties in identifying some features, such as windows frames, and it was proposed to analyze the photographs without processing, to mitigate these identifications. The cadaster form was successfully completed using a combination of the techniques in this study.

Originality/value

This study brings a first proposal for the characterization of parcels for cadastral purposes, by remote sensing techniques, reducing the entry in the parcels for filling cadastral forms, with the evaluation of the proposal in the Brazilian case.

Details

International Journal of Building Pathology and Adaptation, vol. 42 no. 2
Type: Research Article
ISSN: 2398-4708

Keywords

Executive summary
Publication date: 17 April 2024

CHINA/UNITED STATES: Military ties will improve

Details

DOI: 10.1108/OXAN-ES286483

ISSN: 2633-304X

Keywords

Geographic
Topical
Article
Publication date: 29 March 2024

Zhuoer Yao, Zi Kan, Daochun Li, Haoyuan Shao and Jinwu Xiang

The purpose of this paper is to solve the challenging problem of automatic carrier landing with the presence of environmental disturbances. Therefore, a global fast terminal…

Abstract

Purpose

The purpose of this paper is to solve the challenging problem of automatic carrier landing with the presence of environmental disturbances. Therefore, a global fast terminal sliding mode control (GFTSMC) method is proposed for automatic carrier landing system (ACLS) to achieve safe carrier landing control.

Design/methodology/approach

First, the framework of ACLS is established, which includes flight glide path model, guidance model, approach power compensation system and flight controller model. Subsequently, the carrier deck motion model and carrier air-wake model are presented to simulate the environmental disturbances. Then, the detailed design steps of GFTSMC are provided. The stability analysis of the controller is proved by Lyapunov theorems and LaSalle’s invariance principle. Furthermore, the arrival time analysis is carried out, which proves the controller has fixed time convergence ability.

Findings

The numerical simulations are conducted. The simulation results reveal that the proposed method can guarantee a finite convergence time and safe carrier landing under various conditions. And the superiority of the proposed method is further demonstrated by comparative simulations and Monte Carlo tests.

Originality/value

The GFTSMC method proposed in this paper can achieve precise and safe carrier landing with environmental disturbances, which has important referential significance to the improvement of ACLS controller designs.

Details

Aircraft Engineering and Aerospace Technology, vol. 96 no. 3
Type: Research Article
ISSN: 1748-8842

Keywords

Article
Publication date: 13 April 2023

Sadia Samar Ali, Shahbaz Khan, Nosheen Fatma, Cenap Ozel and Aftab Hussain

Organisations and industries are often looking for technologies that can accomplish multiple tasks, providing economic benefits and an edge over their competitors. In this…

Abstract

Purpose

Organisations and industries are often looking for technologies that can accomplish multiple tasks, providing economic benefits and an edge over their competitors. In this context, drones have the potential to change many industries by making operations more efficient, safer and more economic. Therefore, this study investigates the use of drones as the next step in smart/digital warehouse management to determine their socio-economic benefits.

Design/methodology/approach

The study identifies various enablers impacting drone applications to improve inventory management, intra-logistics, inspections and surveillance in smart warehouses through a literature review, a test of concordance and the fuzzy Delphi method. Further, the graph theory matrix approach (GTMA) method was applied to ranking the enablers of drone application in smart/digital warehouses. In the subsequent phase, researchers investigated the relation between the drone application's performance and the enablers of drone adoption using logistic regression analysis under the TOE framework.

Findings

This study identifies inventory man agement, intra-logistics, inspections and surveillance are three major applications of drones in the smart warehousing. Further, nine enablers are identified for the adoption of drone in warehouse management. The findings suggest that operational effectiveness, compatibility of drone integration and quality/value offered are the most impactful enablers of drone adoption in warehouses. The logistic regression findings are useful for warehouse managers who are planning to adopt drones in a warehouse for efficient operations.

Research limitations/implications

This study identifies the enablers of drone adoption in the smart and digital warehouse through the literature review and fuzzy Delphi. Therefore, some enablers may be overlooked during the identification process. In addition to this, the analysis is based on the opinion of the expert which might be influenced by their field of expertise.

Practical implications

By considering technology-organisation-environment (TOE) framework warehousing companies identify the opportunities and challenges associated with using drones in a smart warehouse and develop strategies to integrate drones into their operations effectively.

Originality/value

This study proposes a TOE-based framework for the adoption of drones in warehouse management to improve the three prominent warehouse functions inventory management, intra-logistics, inspections and surveillance using the mixed-method.

Details

Benchmarking: An International Journal, vol. 31 no. 3
Type: Research Article
ISSN: 1463-5771

Keywords

Open Access
Article
Publication date: 16 March 2023

Imoh Antai and Roland Hellberg

The total defence (TD) concept constitutes a joint endeavour between the military forces and civil defence structures within a TD state. Logistics is essential for such joint…

Abstract

Purpose

The total defence (TD) concept constitutes a joint endeavour between the military forces and civil defence structures within a TD state. Logistics is essential for such joint collaboration to work; however, the mismatch between military and civil defence logistics structures poses challenges for such joint collaboration. The purpose of this paper is to identify logistics concept areas within the TD framework that allow for military and civil defence collaborations from a logistics operations perspective.

Design/methodology/approach

Pattern-matching analysis is used to compare patterns found in the investigated case with those prescribed from the literature and predicted to occur. The study seeks to identify logistics concepts within TD from the literature and from the events describing the Swedish response to the Covid-19 pandemic. Pattern matching thus allows for the reconciliation of logistics concepts from the literature to descriptions of how the response was handled, albeit under a TD framework.

Findings

Findings show quite distinct foci between the theoretical and observational realms in terms of logistics applications. While the theoretical realm identifies four main logistics concepts, the observational realm identifies five logistics conceptual themes. This goes on to show an incongruence between the military and civil parts of the TD.

Research limitations/implications

This study provides basis for further research into the applications and management of logistics activity within TD and emergency response.

Originality/value

Logistics applications within TD have not, until now, received much attention in the literature. Given this knowledge gap, this study is of original value.

Details

Journal of Humanitarian Logistics and Supply Chain Management, vol. 14 no. 2
Type: Research Article
ISSN: 2042-6747

Keywords

Abstract

Details

Time of Death
Type: Book
ISBN: 978-1-80455-006-9

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