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The purpose of this paper is to provide a detailed insight into the global military robot industry with an emphasis on products and their applications.

Following an introduction which includes a brief historical account, this provides an industry overview, including various market dimensions and a discussion of the geopolitical and technological factors driving market development. The three following sections provide details of land, airborne and marine robots, their capabilities and deployments in recent conflicts. Finally, brief conclusions are drawn.

Military robots which operate on land, in the air and at sea constitute a multi-billion dollar industry which is growing rapidly. It is being driven by geopolitical tensions, notably the military-technology arms race between China and the USA and the conflict in Ukraine, together with technological progress, particularly in AI. Many robots possess multi-functional capabilities, and the leading application is presently intelligence, surveillance and reconnaissance. An increasing number of heavily armed robots are being developed, and AI has the potential to impart these with the capacity to deliver lethal force without human intervention. Although heavily criticised in some quarters, this capability has probably already been deployed on the battlefield. With ever-growing military budgets, escalating political tensions and technological innovations, robots will play an increasingly significant role in future conflicts.

This provides a detail account of military robots and their role in modern warfare.

Tandem wing aircrafts belong to an unconventional configurations group, and this type of design is characterised by a strong aerodynamic coupling, which results in lower induced drag. The purpose of this paper is to determine whether a certain trend in the wingspan impact on aircraft dynamic stability can be identified. The secondary goal was to compare the response to control of flaps placed on a front and rear wing.

The aerodynamic data and control derivatives were obtained from the computational fluid dynamics computations performed by the MGAERO software. The equations of aircraft longitudinal motion in a state space form were used. The equations were built based on the aerodynamic coefficients, stability and control derivatives. The analysis of the dynamic stability was done in the MATLAB by solving the eigenvalue problem. The response to control was computed by the step response method using MATLAB.

The results of this study showed that because of a strong aerodynamic coupling, a nonlinear relation between the wing size and aircraft dynamic stability proprieties was observed. In the case of the flap deflection, stronger oscillation was observed for the front flap.

Results of dynamic stability of aircraft in the tandem wing configuration can be found in the literature, but those studies show outcomes of a single configuration, while this paper presents a comprehensive investigation into the impact of wingspan on aircraft dynamic stability. The results reveal that because of a strong aerodynamic coupling, the relation between the span factor and dynamic stability is nonlinear. Also, it has been demonstrated that the configuration of two wings with the same span is not the optimal one from the aerodynamic point of view.

A computational fluid dynamics based parametric analysis for shell and helical tube heat exchanger (SHTHE) using CuO/water and Al₂O₃/water nanofluids is the main purpose of the present work. The parameters having impact on the performance of a heat exchanger have been studied in depth. As the solid nanoparticle shows higher thermal conductivity compared to liquid particles, inclusion of this nanoparticle into the base fluid significantly enhances the thermal conductivity of the liquid. Incorporation of nanofluid in the heat exchanger can increase its performance.

The simulation is performed in Solid-Works flow simulation, and the performance of SHTHE is observed by varying the pitch of helical tube from 0.013 to 0.018 m and coil diameter from 0.0813 to 0.116 m, keeping the other parameters constant. The tube side and shell side flow rate is kept as 2 LPM.

The results indicate that the effectiveness of the heat exchanger increases with the increase of pitch and coil diameter. The maximum effectiveness of 0.5022 for CuO/water and 0.4928 for Al₂O₃/water nanofluid is observed at a pitch of 0.018 m and the coil diameter of 0.116 m.

It is observed that CuO/water nanofluid shows better performance compared with Al₂O₃/water nanofluid. For a coil diameter of 0.116 m and pitch of 0.018 m, the SHTHE with CuO/water nanofluid shows 1.82% greater effectiveness compared to the effectiveness with Al₂O₃/water nanofluid.

The purpose of this paper is to provide an insight into the present-day state of bin picking by considering research, technology, products and applications.

Following a short introduction, this first provides examples of recent bin picking research. It then discusses a selection of commercial product developments and applications. Finally, brief conclusions are drawn.

Bin picking has the potential to eliminate repetitive, manual part handling practices in many sectors of the manufacturing and logistics industries. Systems combine robotic gripping and manipulation with machine vision and specialist software and tend to be complex to install and commission. They are produced by robot manufacturers, system integrators, software developers and machine vision specialists and all are constantly developing and improving the technology. These developments are supported by a strong academic research effort, much involving artificial intelligence methods, and while the technology is evolving rapidly, it is yet to reach the point where deployments are routine and widespread.

This provides a timely review of recent bin picking research and commercial developments.

To date, there are no studies in the literature that provide a comprehensive understanding of the interrelationships between the slenderness ratio and the main design criteria in supertall towers (=300 m). In this paper, this important issue was explored using detailed data collected from 75 cases.

This paper was carried out with a comprehensive literature review including the database of the Council on Tall Buildings and Urban Habitat(CTBUH) (CTBUH, 2022), peer-reviewed journals, MSc theses and PhD dissertations, conference proceedings, fact sheets, architectural and structural magazines and other Internet sources. In this study, the case study method was also used to gather and consolidate information about supertall towers to analyze the interrelationships. Cases were 75 supertall buildings in various countries [44 from Asia (37 from China), 16 from the Middle East (6 from Dubai, the United Arab Emirates), 11 from the United States of America and 3 from Russia, 1 from the UK].

The paper's findings highlighted as follows: (1) for buildings in the height range of 300–399 m, the slenderness ratio was usually between 7 and 7.9 and megatall towers were frequently built at a slenderness ratio of 10–15; (2) the median slenderness ratio of buildings in the 400–599 m height ranges was around 8.6; (3) a trend towards supertall slender buildings (=8) was observed in Asia, the Middle East and North America; (4) residential, office and mixed-use towers had a median slenderness ratio of over 7.5; (5) all building forms were utilized in the construction of slender towers (>8); (6) the medium slenderness ratio was around 8 for supertall buildings constructed with outriggered frame and tube systems; (7) especially concrete towers reached values pushing the limits of slenderness (>10) and (8) since the number of some supertall building groups (e.g. steel towers) was not sufficient, establishing a scientific relationship between aspect ratio and related design criteria was not possible.

To date, there are no studies in the literature that provide a comprehensive understanding of the interrelationships between the slenderness ratio and the main design criteria in supertall towers (=300 m). This important issue was explored using detailed data collected from 75 cases.

The purpose of this paper is to investigate a novel approach toward electromagnetic launch.

The field of linear electromagnetic acceleration aims at accelerating macroscopic masses (up to several kg) to speeds in excess of 2 km/s. This can be achieved using accelerators of the railgun type. The innovation of this work lies in the use of multiphase current instead of the classically used quasi-direct current (DC). The approach taken is to work out in a first step the potential performance of such a configuration, for example, by showing that a constant propulsive force can be realized. Next, the necessary changes for the system setup were carefully analyzed. Both the accelerator and the power supply have to be considerably modified with regard to the classical approach.

Thorough analysis of the electromagnetic behavior of the launcher including nonlinear effects lead to an innovative system design which is considered to be the main finding of the work presented here. Moreover, a prototype was build. The preliminary experimental results obtained are in very good agreement with corresponding simulations validating the underlying modeling approach.

For the purpose of this paper, power levels of only 450 kVA are considered. However, this research can be used to design more powerful devices in the future.

While DC powered railguns are modeled very well in a variety of papers, the use of multiphase alternating current is not very well discussed yet. It could be of value for launch scenarios, for which very high speeds are required such as the launch of micro satellites to space.

This paper aims to present a numerical study that investigates the flow of MgO-Al₂O₃/water hybrid nanofluid inside a porous elliptical-shaped cavity, in which we aim to examine the performance of this thermal system when exposed to a magnetic field via heat transfer features and entropy generation.

The configuration consists of the hybrid nanofluid out layered by a cold ellipse while it surrounds a non-square heated obstacle; the thermal structure is under the influence of a horizontal magnetic field. This problem is implemented in COMSOL multiphysics, which solves the related equations described by the “Darcy-Forchheimer-Brinkman” model through the finite element method.

The results illustrated as streamlines, isotherms and average Nusselt number, along with the entropy production, are given as functions of: the volume fraction, and shape factor to assess the behaviour of the properties of the nanoparticles. Darcy number and porosity to designate the impact of the porous features of the enclosure, and finally the strength of the magnetic induction described as Hartmann number. The outcomes show the increased pattern of the thermal and dynamical behaviour of the hybrid nanofluid when augmenting the concentration, shape factor, porosity and Darcy number; however, it also engenders increased formations of irreversibilities in the system that were revealed to enhance with the permeability and the great properties of the nanofluid. Nevertheless, this thermal enhanced pattern is shown to degrade with strong Hartmann values, which also reduced both thermal and viscous entropies. Therefore, it is advised to minimize the magnetic influence to promote better heat exchange.

The investigation of irreversibilities in nanofluids heat transfer is an important topic of research with practical implications for the design and optimization of heat transfer systems. The study’s findings can help improve the performance and efficiency of these systems, as well as contribute to the development of sustainable energy technologies. The study also offers an intriguing approach that evaluates entropy growth in this unusual configuration with several parameters, which has the potential to transform our understanding of complicated fluid dynamics and thermodynamic processes, and at the end obtain the best thermal configuration possible.

Abnormal vibrations often occur in the liquid oxygen kerosene transmission pipelines of rocket engines, which seriously threaten their safety. Improper handling can result in failed rocket launches and significant economic losses. Therefore, this paper aims to examine vibrations in transmission pipelines.

In this study, a three-dimensional high-pressure pipeline model composed of corrugated pipes, multi-section bent pipes, and other auxiliary structures was established. The fluid–solid coupling method was used to analyse vibration characteristics of the pipeline under various external excitations. The simulation results were visualised using MATLAB, and their validity was verified via a thermal test.

In this study, the vibration mechanism of a complex high-pressure pipeline was examined via a visualisation method. The results showed that the low-frequency vibration of the pipe was caused by fluid self-excited pressure pulsation, whereas the vibration of the engine system caused a high-frequency vibration of the pipeline. The excitation of external pressure pulses did not significantly affect the vibrations of the pipelines. The visualisation results indicated that the severe vibration position of the pipeline thermal test is mainly concentrated between the inlet and outlet and between the two bellows.

The results of this study aid in understanding the causes of abnormal vibrations in rocket engine pipelines.

The causes of different vibration frequencies in the complex pipelines of rocket engines and the propagation characteristics of external vibration excitation were obtained.

Before designing a navigation system, it is necessary to analyse possible approaches in terms of expected accuracy, existing limitations and economic justification to select the most advantageous solution. This paper aims to collect possible navigation methods that can provide correction for inertial navigation and to evaluate their suitability for use on a manoeuvring tactical missile.

The review of existing munitions was based on data collected from the literature and online databases. The data collected included dimensions, performance, applied navigation and guidance methods and their achievable accuracy. The requirements and limitations identified were confronted with the range of sensor parameters available on the market. Based on recent literature, navigation methods were reviewed and evaluated for applicability to inertial navigation system (INS) correction in global navigation satellite system-denied space.

The performance analysis of existing munition shows that small and relatively inexpensive micro-electro-mechanical system-type inertial sensors are required. A review of the parameters of existing devices of this type has shown that they are subject to measurement errors that do not allow them to achieve the delivery accuracy expected of precision missiles. The most promising navigation correction methods for manoeuvring flying objects have been identified.

The information presented in this paper is the result of the first phase of a project and presents the results of the requirements selection, initial sizing and preliminary design of the navigation system. This paper combines a review of the current state of the art in missile systems and an analysis of INS accuracy including the selection of sensor parameters.

This paper aims to explore how traditional industries revert the trend of decline in sales through rebranding by analyzing the extended case study of the fountain pen industry.

This study analyzes the marketing in case study of the fountain pen industry through two coordinates – symbolizing status and branding nostalgia. The division of analyses in these categories is supplanted by data, such as linear regression to analyze changes in product characteristics.

This study finds that the rebranding of the fountain pen in multiple fitting images – status symbol, object of nostalgia and something scarce and unique – is successful in capturing consumer demand, shaping consumer perceptions and help the mature industry locate as well as enter a niche market.

To the best of the authors’ knowledge, this paper is the first one to explore the business development of traditional industry as a case study of fountain pens from the perspective of marketing and consumer behavior.