bluuebunny/crossref_metadata_2025 huggingface dataset:
Investigations of Movement Focusing Lens by Total Station Influence on the Vertical Index Error
Authors: Nikonov A. V. , Ryabova N. M. , Smirnov A. D. , Iskakov D. M. , Barannikov D. A.
Published: October 2022

If it is necessary to determine the heights of a large number of points, it is effective to use fan-shaped trigonometric leveling. The length of sights can change within a wide range, so it is important to know what influence the movement of the focusing lens in the vertical index error of the total station can have. The aim of the study is to determine the dependence of vertical index error on the distance to the surveying target. Three total stations were used in the work, the vertical index error was determined when the target was located at a distance of 3 to 100 m. It was established that when the target is moved in the distance range from 3 to 15 m, vertical index error change by 5-10ʹʹ. In each total station when moving the focusing lens, the location of vertical index error changes individually.
Overview of the main socio-economic indicators displayed on thematic maps
Authors: Mironova S. A. , Radchenko L. K.
Published: October 2022

In order to study and analyze socio-economic indicators displayed on thematic maps of different regions of the Russian Federation, a number of thematic maps presented in atlases are analyzed: Novosibirsk region, Republic of Buryatia, Amur region. The methods of cartographic representation of indicators on maps are determined. The main socio-economic indicators on the considered maps are revealed in accordance with the indicators presented by Rosstat. As a result, conclusions are drawn about the most used cartographic methods of depicting socio-economic indicators on thematic maps and about cartographic solutions for transmitting additional information in the form of various techniques. Analytical, synthetic and cartographic methods were used in the study.
Correction of FAGN points velocities by results of GNSS measurements
Authors: Gienko E. G.
Published: October 2022

The method of determining the velocities of the Fundamental Astronomical and Geodetic Network (FAGN) points from the coordinates time series obtained from processing GNSS measurements is considered. The criteria for estimation the quality of the solution, the issues of adequate estimation of accuracy and data control are presented. Proposals for the compilation of a priori weight matrix of measurements and velocities are considered. The importance of preliminary detection and exclusion of rough measurements is noted. The results of determining the OXTK point velocities are presented, the analysis of the results is demonstrated. It is proposed to use the decision analysis tools discussed in the article when automating the process of determining the FAGS points velocities, and the listed criteria for evaluating the results should be displayed in reports. It is recommended to publish on the RGS-center website not only the coordinates and velocities of the FAGS points, but also their average square errors.
Use of automated geodetic devices when assembling technological equipment
Authors: Skripnikov V. A. , Skripnikova M. A. , Andosova A. M. , Sladkevich O. A.
Published: October 2022

The article considers the method of determining the geometric parameters of technological equipment with the use of automated total stations. It analyses the results of production work to determine the spatial position of the equipment. It is noted that under certain conditions, the use of total stations allows determining the spatial position of control points on the equipment with the necessary accuracy. The preliminary investigations of accuracy by all modes of measurements distances and angles in the laboratory conditions and conditions, as close as possible to real are recommended. To perform measurements at short distances, an improved measurement technique is proposed. The peculiarity of the proposed technique is that during measurements it is proposed to use simultaneously a high-precision automated total station and a high-precision digital level. The article gives the results of measurements. It is established that the considered technique makes it possible to increase the accuracy of determining the control points’ marks on the equipment.
Development of a technological scheme for creating vertical topographic plans
Authors: Ustavich G. A. , Khlebnikova T. A. , Astapov A. M.
Published: October 2022

On a modern industrial site, it is regularly necessary to solve a number of tasks related to work on vertical objects (reconstruction of facades, installation and replacement of communications of industrial enterprises, etc.). Modern approaches to the creation of geodetic materials for solving these tasks do not meet modern requirements and do not provide the necessary level of informativeness. The authors of the article propose to use a new type of materials - vertical engineering topographic plans of scales 1: 500 and 1: 200. As a basis for a vertical engineering topographic plan, it is proposed to use orthophotomaps, digital models obtained using materials from unmanned aerial systems (UAS), converted standard topographic plans. The results of the processing of survey materials of civil buildings, obtained by means of UAS, are presented. The fundamental possibility of using survey materials to obtain vertical engineering and topographic plans at scales of 1: 500 and 1:2 00 is revealed.
Creation of control network for aerial surveys in open-pit workings using UAV
Authors: Khmyrova E. N. , Tutanova M. S. , Tokar D.
Published: October 2022

To assess the condition of the instrument array at the Aksu field, the earth's surface has been monitored since 2018. The territory of the mining and technical facilities of the Aksu deposit is characterized by a varying degree of complexity of the relief and a variety of the structure of the composing rocks. At the first stage, instrumental geodetic monitoring was organized to identify active deformations on the object under study using observation profile lines located in the zone of Earth surface movements. Based on the monitoring results, an assessment of the condition of the instrument array of the deposit was carried out and decisions were made on systematic observations of the movement of the Earth's surface using digital aerial photography. A deformation monitoring program has been developed at the site under study, including a project for creating a geometric pattern of signs and a zone of possible and existing deformations has been determined. Aerial photography was carried out with the help of UAVs at intervals every half a year starting in 2020. According to the results of aerial survey, local zones of new deformations on the earth's surface were obtained, as a result of mining underground work at the Aksu mine. Monitoring continues, the next flight of aerial photography is planned for May-June 2022.
The study of 3D modelling accuracy using terrestrial laser scanning data of Geomax Zoom 300
Authors: Altyntsev M. A. , Geraschenko G. D.
Published: October 2022

One of the tasks solved by terrestrial laser scanning data is three-dimensional modeling of territories. Due to the high density of the resulting point cloud, it is possible to create three-dimensional models of objects with a high level of detail. To date, a large number of models of laser scanners have been released, the technical characteristics of which can be significantly distinguished. To understand the possible accuracy of constructing three-dimensional modes based on the data of a certain laser scanner model and where the scan positions should be placed, a number of studies have to be preliminary performed. The accuracy analysis of the laser scanning data obtained using Geomax Zoom 300 and the results of three-dimensional modeling based on control measurements is carried out. Recommendations have been proposed for the use of this laser scanner model to construct 3D models of maximum possible accuracy and detail.
Regulatory framework for the formation of the system information security of a nuclear facility
Authors: Kuznetsova E. A. , Fionov A. N.
Published: October 2022

The vulnerability of nuclear facilities to deliberate attack raises concerns in the field of nuclear safety. After all, most nuclear facilities are vulnerable to attacks that can lead to widespread radioactive contamination. If the use of nuclear energy is to expand significantly, nuclear facilities must be extremely protected from attacks that can release huge amounts of radioactivity into the community. This article will consider the main regulatory documents that will be the basis for the formation of an information security system for nuclear facilities. The purpose of the work is to analyze the regulatory framework in the field of information security in relation to facilities implementing various nuclear technologies. The task is to develop technical requirements for information security systems that take into account the specifics of such objects.
Home Computer Security
Authors: Markelova E. B. , Popkov G. V.
Published: October 2022

Our life is firmly connected with information technologies: messengers, social networks, online stores - we use all these means of communication and communication on a daily basis. That is why information security plays an important role. Taking into account the rapid development of information technologies, it is becoming increasingly difficult to protect information, which is why the need to protect a computer from unauthorized access, theft of confidential information, exposure to malware is a priority in the field of computer technology and information security. This article presents the main threats to the security of a home computer, presents the results of a comparative analysis of ways to protect a home computer from virus, spyware, hacker, advertising and spam attacks, as well as from unauthorized access to information stored on a personal computer.
Research of firmware of PON routers for software bookmarks
Authors: Peshkow D. E. , Shabrova A. V.
Published: October 2022

Network routers are an integral part of any corporate and home network. The number of devices in an organization's network can number in the dozens and it is not always possible to monitor the relevance of versions or their security. This is often used by malefactors and unscrupulous manufacturers. And in order not to prevent the consequences of a hacker attack, it is necessary to carry out activities in a timely manner to ensure information security. And you need to start with network devices and their diversity. Each such device has a firmware that specialists can check and detect both vulnerabilities and planned software bookmarks, such as backdoors, in it. To simplify and speed up this work, you can use a firmware scanner.
Ranking of security measures of significant objects of critical information infrastructure
Authors: Sitskaya A. V. , Selifanov V. V.
Published: October 2022

One of the main tasks of the state is the proper functioning of internal systems that provide a decent standard of living for citizens. But what actually ensures the functioning of the activities of the state in various areas? Critical information infrastructures and their significant objects, as well as telecommunication networks used to organize the interaction of such objects, have become one of the main support systems. Order of the FSTEC of Russia No. 239 contains protection measures, but does not describe methods for assessing the effectiveness of protection of significant objects of critical information infrastructure, which in turn casts doubt on the quality of assessment of built protection systems. This article discusses the ranking of threats and the development of a method for evaluating the effectiveness of the built protection system based on weighting factors. The developed method is based on the methodology for assessing the level of security protection of the information system of the Central Bank of Russia
Research on Information Security Risk Assessment Techniques
Authors: Smirnov R. A. , Novikov S. N.
Published: October 2022

The emergence of new technologies not only generates new methods of attacks, but also expands the existing list of threats, and, as you know, each threat can be carried out by a large number of different attacks. To date, there are methods based on various approaches to the study of information security threats, such as: assessment of the relevance of information security threats according to the FSTEC methodology of Russia, ATT&CK Matrix for Enterprise, Howard-Longstaff incident taxonomy, information security threat assessment study based on a security model. All of the above methods can be divided into two groups of threat assessment: quantitative and qualitative. In this connection, there is a need to conduct their research. The article presents a study of methods for assessing information security threats, conducted in various ways.
Problems of geoinformation modeling of metropolis infrastructure accessibility for people with limited mobility
Authors: Cilichenko A. A.
Published: October 2022

The accessibility of the infrastructure of settlements for low-mobility groups of the population still remain relevant in the Russian Federation. The state program Accessible Environment, which has been operating since 2011, is aimed at solving this problem. The cartographic and geodetic industry can and should contribute to the implementation of the program, since spatially coordinated information about the accessibility of the territory allows you to visualize and assess the current state of the territory, outline optimal ways to solve the problem of accessibility, build accessible routes when planning the movement of citizens around the city. The author suggests using the methods of mobile laser scanning to obtain a digital model of the surveyed travel route. A technological scheme for constructing a geoinformation model of the accessibility of the territory using three-dimensional laser scanning methods is presented.
Categorization of CII objects in the defense industry
Authors: Cypkina A. V. , Shaburova A. V.
Published: October 2022

In modern times, critical information infrastructures of enterprises are increasingly being attacked. Each time these attacks become more malicious. Since the organization's activities directly depend on the smooth operation of its information systems, it is necessary to ensure the safety of these facilities. This article discusses the main stages of categorization of critical information infrastructure objects. We also study the items necessary for organizations to perform, which by default belong to the field of activity that falls within the critical information infrastructure. An example of such an organization in this article is a military-industrial enterprise, which has its own main features when carrying out the categorization procedure. The relevance of the topic of categorizing critical information infrastructure is explained by the importance of the defense industry in ensuring the national security of the Russian Federation.
Preparation and performance of work to increase the accuracy of the reference torrential installation in accordance with the state verification scheme
Authors: Shakalov K. A. , Vikhareva N. A.
Published: October 2022

Carrying out primary analysis and studies of factors leading to an increase in the error of reference flowing installations, including the main contribution of the error of reference flow meters. The influence of the geometric characteristics of the measuring section, of local hydraulic resistances, as well as the influence of the location of reference flow meters on the parameters of the volumetric flow rate of the liquid are investigated. By taking into account the factors under study, prepare work to change the design and component composition, which will increase the accuracy of the standard torrential installation in accordance with the state verification scheme.
Problems of formalization of ISMS processes
Authors: Antipov V. E. , Selifanov V. V.
Published: October 2022

This article raises the problem of formalization of processes in the information security management system. The question of the necessity and importance of the stage of formalization of processes, the study and analysis of national and international standards is considered. In the course of the work, approaches to the development of an information security management system were analyzed, as well as national standards ГОСТ Р ИСО/МЭК 27001-2006, ГОСТ Р ИСО/МЭК 27002-2012 and ГОСТ Р ИСО/МЭК 27005-2010, which are the main ones when creating an information security management system (ISMS) and approaches to assessing its risks. Taking into account the provisions of national standards, as well as having studied different approaches to the development of ISMS, practical recommendations for the formalization of ISMS processes have been formed in this article. All recommendations are aimed at ensuring the safety of employees and the organization, while implementing formalization processes for the appropriate information security management system. Also, using the example of one security measure from the ISO/IEC 27001 standard, one of the ways to implement the policy regarding the formalization of the processes affecting the presented measure is presented.
Development of a Universal Algorithm for Determining the Spatiо-Temporal State of Man-Made Systems Based on Time Series of Geodetic Measurements
Authors: Golub E. F. , Bugakova Т. Yu.
Published: October 2022

The complexity of modern man-made systems (engineering structures) is associated with issues of safety of their operation. The effects of endogenous and exogenous factors lead to a change in the state of systems. In this regard, there is a need to improve methods and means of determining the condition of structures to ensure the safety of their operation. The article discusses the methods of geodetic measurements of the spatio-temporal states of engineering structures, provides an analysis of data processing software, and draws conclusions about the advantages and disadvantages of modern software. Based on the research, a complex algorithm that allows unifying the procedure for determining the spatial and temporal state of engineering structures of different shapes and designs, taking into account the individual selection of mathematical algorithms for assessing and timely warning of emergency situations is offered. The conceptual scheme of the complex algorithm includes the procedure of actions and a set of mathematical models, which makes it possible to determine the spatial and temporal state of engineering structures of any design for a wide range of purposes.
Issues of formation of risk management of significant objects of critical information infrastructure
Authors: Kidyaeva S. M. , Shaburova A. V. , Selifanov V. V.
Published: October 2022

With the increasing number of attacks related to information security, enterprises need to review the principles of risk management, to maintain the relevance and increase the reliability of information security management system. The article considers topical issues of risk management of significant objects of critical information infrastructure. International standards on information security ISO/IEC27001-2021, ISO/IEC 27005-2010 and requirements of the Federal Law of July 26, 2017. № 187-FL "On the security of critical information infrastructure of the Russian Federation". In particular, the rules of categorization of critical information infrastructure objects approved by the Government Decree of February 8, 2018. № 127 «On approving the rules of categorizing objects of critical information infrastructure of the Russian Federation, as well as the list of indicators of criteria for the significance objects of critical information infrastructure of the Russian Federation and their values were analyzed» regarding information security risk management are analyzed. A comparative table of the risk management process for an organization that has significant critical information infrastructure facilities and the categorization process for critical information infrastructure facilities is presenting. Developed recommendations for maintaining the relevance of risk management of critical information infrastructure entities.
Proposal to modify the Russian standard for electronic digital signature in order to eliminate the broadband covert channel
Authors: Klevtsov A. A. , Fionov A. N.
Published: October 2022

Most digital signature algorithms have the ability to organize hidden channels for transmitting information. Their presence was revealed after the publication of a digital signature scheme based on the El-Gamal cipher. The bandwidth of these channels ranges from a few bits (narrowband channels) to 256-512 bits (broadband channels). The literature describes several ways to eliminate broadband channels with the help of a supervisor. The analysis of existing methods of elimination of hidden channels in digital signature algorithms is given. The shortcomings of the existing schemes are revealed. A method of modification of the Russian standard of electronic digital signature GOST R 34.10-2012 has been developed in order to eliminate the broadband hidden channel. The method provides for the presence of a supervisor who does not participate in the formation of the signature and can check signed messages for the absence of hidden channels.
Analysis of bacterial diversity associated with commercial broiler chicken in Lahore, Pakistan
Authors: Azam Farhana , Tanveer Sana , Ali Basharat
Published: October 2022

Chicken (Gallus gallus domesticus) is the most widely domesticated animal worldwide. Food biosafety is a great concern for consumers, producers, and public health organizations around the world. The poultry sector contributes 3.1% to the GDP of Pakistan. Infections caused by bacteria and viruses in poultry pose a serious threat to consumer health and economic burden in Pakistan while accurate figures are still unknown due to several factors, including inadequate surveillance, management, monitoring, and infection control. The chicken samples were procured from Shadman, Moon, Karim Block, Tollinten, Jallo and Wapda Town meat market of Lahore, Pakistan. Overall, 63 bacterial strains were isolated from complex and selective media and further processed for characterization. The 16S rRNA gene sequencing of bacterial strains were exhibiting genetic similarity with Proteus, Shigella, Providencia, Escherichia, Citrobacter, Klebsiella, Myroides, Enterococcus, Serratia, Staphylococcus, Bacillus, Macrococcus and Kluyvera. Bacterial strains were evaluated for antibiotic susceptibility testing, swarming motility, and biochemical tests. Antibiotic susceptibility was tested by using discs of tetracycline, gentamycin, streptomycin and chloramphenicol. Bacterial strains were recorded as resistant to all antibiotics except chloramphenicol. It was confirmed that chicken meat was infested with potential opportunistic human pathogens. To overcome the foodborne illnesses and to control the microbial load, food safety measures should be taken by following the standard protocols. In Pakistan, slaughterhouse environment, their sanitary conditions, storage, and transportation may be responsible in spreading the pathogens to food products.
A Time-Domain Finite-Difference Method for Bending Waves on Infinite Beams on an Elastic Foundation
Authors: Stampka Katja , Sarradj Ennes
Published: October 2022

To model the vibration and structure-borne sound excitation and propagation of a railway rail, it can be modeled as an infinite beam on an elastic foundation. Existing analytical or numerical models are either formulated in the frequency domain or consider only finite beams in the time domain. Therefore, a time-domain approach for bending wave propagation on an effectively infinite beam on an elastic foundation is proposed. The approach makes use of an implicit finite-difference method that allows for varying properties of the beam and the foundation along the length of the beam. Strategies for an efficient discretization are discussed. The method is validated against existing analytical models for a single layer and two layers, as well as continuous and discrete support. The results show very good agreement, and it can be concluded that the proposed method can be seen as a versatile method for simulating the behavior of a beam on different kinds of elastic foundations.
Study on Fault Detection of Plastic Micro-Drive System: An Experimental Analysis of Grille Controller
Authors: Huang Qingqing , Li Jing , Zhang Ziqiang , Liu Xin , Luo Jiufei , Zhang Bin
Published: October 2022

Plastic micro-drive systems are used in an increasing number of applications in manufacturing industries. The operational status of the plastic micro-drive system directly affects the performance of the host system. However, the fault diagnosis of the plastic micro-drive system remains a challenge due to its miniaturization. In this paper, a fault-detection study using the electrical-parameter analysis method is proposed for the grille controller, which provides a basis for typical plastic micro-drive systems. The structure and working principle of grille controllers are analyzed, and typical faults are summarized. Then, the fault-mechanism analysis of typical faults is presented, and the identification indicators of faults are developed. A strategy of fault-feature frequency extraction based on the improved reconstruction method of empirical-mode decomposition (EMD) is proposed. Finally, the experimental results reveal that the proposed indicators and method demonstrate high accuracy for the grille-controller fault detection.
Two-Phase Stator Vibration Amplitude Compensation of Traveling-Wave Ultrasonic Motor
Authors: Gao Xiaochen , Yang Ming , Zhu Yuanfei , Hu Yinghua
Published: October 2022

The consistency of the two-phase mode responses is essential to ensure the mechanical performance and stability of traveling-wave ultrasonic motors. Due to the asymmetry of the stator, inevitable manufacturing errors, or imbalance of the excitation voltages, the amplitudes of the two-phase standing waves cannot be exactly the same, resulting in unstable operating of USM. To improve the stability of the motor and decrease the velocity fluctuation, a closed-loop velocity control scheme considering two-phase consistency compensation based on the vibration amplitude of the stator is proposed. This scheme is implemented under the framework of the stator vibration amplitude-based velocity control and parallel resonance frequency tracking (VCBVF). Based on the relationship between the velocity and stator vibration amplitude (SVA), two-phase excitation signals are adjusted individually and simultaneously. Compared with the single-phase feedback VCBVF control scheme, experimental results show that the proposed scheme can reduce the overshoot from 17.50% to 6.90% and velocity fluctuations from 7.69 rpm to 2.40 rpm, under different load torques. The proposed scheme can compensate for the two-phase electrical inconsistency and improve the velocity stability and output power of motor operation under various conditions.
Enhancement of Shock Absorption Using Hybrid SMA-MRF Damper by Complementary Operation
Authors: Jacob Kiran , Tan Aditya Suryadi , Sattel Thomas , Kohl Manfred
Published: October 2022

A hybrid damper concept is presented here using a combination of a Magnetorheological (MR) Fluid (MRF) and Shape Memory Alloy (SMA)-based energy dissipation. A demonstration is performed utilizing the shear operating mode of the MRF and the one-way effect of the SMA. The damping performance of different MRF-SMA configurations is investigated and the corresponding energy consumption is evaluated. We demonstrate that the operation of MRF and SMA dampers complement each other, compensating for each other’s weaknesses. In particular, the slow response from the MR damper is compensated by passive SMA damping using the pseudoplastic effect of martensite reorientation, which can dissipate a significant amount of shock energy at the beginning of the shock occurrence. The MR damper compensates for the incapability of the SMA to dampen subsequent vibrations as long as the magnetic field is applied. The presented hybrid SMA-MR damper demonstrates superior performance compared to individual dampers, allowing for up to five-fold reduction in energy consumption of the MR damper alone and thereby opening up the possibility of reducing the construction volume of the MR damper.
Refined Modeling Method and Analysis of an Electromagnetic Direct-Drive Hydrostatic Actuation System
Authors: Lu Jiayu , Gu Chaofan , Zhao Yanjun , Tan Cao , Lu Yingtao , Fu Changzhong
Published: October 2022

The hydrostatic actuation system based on linear actuators improves the complex piston force and long transmission path of the traditional electro-hydrostatic actuator (EHA). However, new nonlinear factors in the linear actuator and direct-driven piston are introduced into the system, which present challenges to system modeling and control. To improve the accuracy of system performance prediction, this paper analyzed the working characteristics of an electromagnetic direct-drive hydrostatic actuation system (EDHAS). A dynamic model of the electromagnetic linear actuator including the LuGre friction model was established. The high-pressure internal leakage of the direct-drive pump was described by an inclined eccentric leakage model. The Karnopp friction model was applied to solve the problem of switching between viscous and sliding friction in a cylinder. The hydraulic components model was established based on AMESim, and the electromagnetic linear actuator model and the system controller model were established in Matlab/Simulink, to establish a refined electromechanical–hydraulic co-simulation model of the EDHAS with electromagnetic, mechanical, hydraulic, and control coupling. A system performance test platform was built. The simulation results of the direct-drive piston displacement, the system pressure, the system flow rate, and the cylinder displacement match well with experimental results, which verifies the validity and accuracy of the refined modeling method.
A Variable Stiffness Actuator Based on Leaf Springs: Design, Model and Analysis
Authors: Lu Yifan , Yang Yifei , Xue Yuan , Jiang Jun , Zhang Qiang , Yue Honghao
Published: October 2022

In order to adapt to complex and changeable mechanical conditions and make the deformable mechanisms perform well statically and dynamically, variable stiffness joints have been studied extensively. The variable stiffness actuator is the key driving component to adjust stiffness of the joint. By inserting flexible elements between the driving and driven ends of rigid motion, the variable stiffness actuator makes the joint move precisely and allows humans to interact with machines safely. At present, many kinds of variable stiffness actuators have been applied, among which the way of changing the length of the force arm of leaf springs has obvious advantages. However, overall configuration design, accurate stiffness model, mechanical characteristics and safety analysis have not been studied in depth. This paper investigates a variable stiffness actuator based on leaf spring by design, model and mechanical analysis. The composition and configuration of the actuator is analyzed and optimized. Using the deflection theory of the beam, a new rotational stiffness model of the actuator is established, and a safe position criterion is set up upon the deformation constraint conditions. The variation law of stiffness and the influence of parameters on mechanical characteristics are studied. The finite element analysis method verified the rotational stiffness model, and static test proved that the actuator could effectively work in the joint.
Adhesion State Estimation for Electrostatic Gripper Based on Online Capacitance Measure
Authors: Sîrbu Ion-Dan , Bolignari Marco , D’Avella Salvatore , Damiani Francesco , Agostini Lorenzo , Tripicchio Paolo , Vertechy Rocco , Pancheri Lucio , Fontana Marco
Published: October 2022

Electroadhesion is a suitable technology for developing grippers for applications where fragile, compliant or variable shape objects need to be grabbed and where a retention action is typically preferred to a compression force. This article presents a self-sensing technique for electroadhesive devices (EAD) based on the capacitance measure. Specifically, we demonstrate that measuring the variation of the capacitance between electrodes of an EAD during the adhesion can provide useful information to automatically detect the successful grip of an object and the possible loss of adhesion during manipulation. To this aim, a dedicated electronic circuit is developed that is able to measure capacitance variations while the high voltage required for the adhesion is activated. A test bench characterization is presented to evaluate the self-sensing of capacitance during different states: (1) the EAD is far away from the object to be grasped; (2) the EAD is in contact with the object, but the voltage is not active (i.e., no adhesion); and (3) the EAD is activated and attached to the object. Correlation between the applied voltage, object material and shape and capacitance is made. The self-sensing EAD is then demonstrated in a closed-loop robotic application that employs a robot manipulator arm to pick and place objects of different kinds.
Design and Analysis of a Compliant End-Effector for Robotic Polishing Using Flexible Beams
Authors: Qin Yanding , Wu Haitao , Li Zhiyuan , Sun Ning , Sun Lei
Published: October 2022

The contact force between the polishing tool and the workpiece is crucial in determining the surface quality in robotic polishing. Different from rigid end-effectors, this paper presents a novel compliant end-effector (CEE) for robotic polishing using flexible beams. The flexibility of the CEE helps to suppress the excessive displacement caused by the inertia of the polishing robot and avoids damaging the polishing tool and workpiece surface. In addition, the contact force can also be precisely estimated via the measurement of the CEE’s displacement using a capacitive position sensor. The design, modeling and experimental validation of the CEE are presented. Firstly, the analytical model of the CEE is established using the stiffness matrix method. Subsequently, the analytical model is verified by finite element analysis. Further, a prototype is manufactured, and its characteristics and performance are experimentally tested. The equivalent stiffness is measured to be 0.335 N/μm, and the first natural frequency along its working direction is 42.1 Hz. Finally, the contact force measurement using the CEE is compared with a force sensor. Under open-loop condition, the resolution of the contact force measurement is found to be 0.025 N, which makes the fine tuning of the contact force possible in robotic polishing.
Effects of Flexural Rigidity on Soft Actuators via Adhering to Large Cylinders
Authors: Wang Liuwei , Jiang Qijun , Weng Zhiyuan , Yuan Qingsong , Wang Zhouyi
Published: October 2022

This study proposes a soft pneumatic actuator with adhesion (SPAA) consisting of a top fluidic-driven elastic actuator and four bottom adhesive pads for adhering to large cylinders. Finite element models were developed to investigate the bending properties under positive air pressure and the effect of “rib” height on the flexural rigidity of the SPAA. A synchronous testing platform for the adhesive contact state and mechanics was developed, and the bending curvature and flexural rigidity of the SPAA were experimentally measured relative to the pressure and “rib” height, respectively, including the adhesion performance of the SPAA with different rigidities on large cylinders. The obtained results indicate that the SPAA can continuously bend with controllable curvature under positive air pressure and can actively envelop a wide range of cylinders of different curvatures. The increase in the “rib” height from 4 to 8 mm increases the flexural rigidity of the SPAA by approximately 230%, contributing to an average increase of 54% in the adhesion performance of the SPAA adhering to large cylinders. The adhesion performance increases more significantly with an increase in the flexural rigidity at a smaller peeling angle. SPAA has a better adhesion performance on large cylinders than most existing soft adhesive actuators, implying that is more stable and less affected by the curvature of cylinders. To address the low contact ratio of the SPAA during adhesion, the optimization designs of the rigid–flexible coupling hierarchical and differentiated AP structures were proposed to increase the contact ratio to more than 80% in the simulation. In conclusion, this study improved the adhesion performance of soft adhesive actuators on large cylinders and extended the application scope of adhesion technology. SPAA is a basic adhesive unit with a universal structure and large aspect ratio similar to that of the human finger. According to working conditions requirements, SPAAs can be assembled to a multi-finger flexible adhesive gripper with excellent maneuverability.
Experimental Investigation of a Roughness Element Wake on a Hypersonic Flat Plate
Authors: Han Junhao , He Lin , Xu Xiwang , Wu Zhengbang
Published: October 2022

An experimental investigation was performed on the wake flow field of an isolated roughness element of a flat plate at Mach 6 by employing the nanoparticle-based planar laser scattering (NPLS) approach. The three-dimensional features and causes of the flow field structure were scrutinized by transient flow field images of roughness elements on various planes. The time-resolved NPLS technique was implemented to examine the time evolution characteristics of the wake flow field of roughness elements. In the following, the process of dynamic evolution of large-scale vortex structures in the wake flow field was methodically assessed. Additionally, the influences of roughness element heights on the wake vortex structure were evaluated and the obtained results were compared.
Numerical Investigation on Aerodynamic Characteristics of an Active Jets-Matrix Serving as Pitch Control Surface
Authors: Tian Songyan , Duan Yanhui , Chen Hongbo
Published: October 2022

To facilitate future Hypersonic Flight Vehicle (HFV) implementation with high maneuverability throughout its reentry trajectory, an Active Jets-Matrix (AJM) is designed to serve as the flapless pitch control surface. The AJM consists of four control groups composed in total of 48 supersonic nozzles. The AJM aims to utilize the jet flow-interaction-induced additional control moment to improve the control efficiency during atmospheric entry. A comparative research method is employed to study the eight simulation cases for three different HFV configurations (baseline, mechanical control surface with 30° deflection, and the AJM configuration) and two AJM control moment adjustment strategies (nozzle chamber pressure regulation and discretized nozzle group on–off control). A conventional in-house computational fluid dynamics (CFD) solver with the two-equation SST turbulence model is employed to undertake the simulation tasks. Simulation results indicate that: (a) only the AJM configuration is capable of trimming the HFV in pitch channel; (b) nonlinearity exists between the augmentation moment and the specific control variable from respective adjustment strategies; (c) the chamber pressure regulation strategy bears higher overall efficiency, while the discretized control strategy induces more intense local jet-flow interaction. With a maximum control moment augmentation of 1.58, the AJM presents itself as a competitive candidate for future HFV flapless control methods.
Closed-Form Analysis of Thin-Walled Composite Beams Using Mixed Variational Approach
Authors: Bae Jae Seong , Jung Sung Nam
Published: October 2022

An analytical methodology is developed for thin-walled composite beams with arbitrary geometries and material distributions. The approach uses a mixed variational theorem which sets the shell displacements, and the shear stress resultants and hoop moments as the unknowns to obtain the stiffness constants at the level of Timoshenko–Vlasov beam. All the field equations and the continuity conditions that should be satisfied over the shell wall are derived in closed form as the part of the analysis. Numerical simulations are conducted to show the validity of the proposed analysis. The comparison of the predicted stresses and the stiffness constants indicates close correlation with those of the detailed finite element (FE)-based analysis and up-to-date beam approaches. Symbolically generated stiffness constants and the sectional warping deformation modes of coupled composite beams are presented explicitly to illustrate the strength of the proposed theory.
Data-Driven Transition Models for Aeronautical Flows with a High-Order Numerical Method
Authors: Chen Yanjun , Wang Shengye , Liu Wei
Published: October 2022

Over the past years, there has been innovative ideas about data-driven turbulence modeling proposed by scholars all over the world. This paper is a continuity of these significant efforts, with the aim of offering a better representation for turbulence physics. Previous works mainly focus on turbulence viscosity or Reynolds stress, while there are few works for turbulence transition. In our work, two mapping functions between average flow parameters and transition intermittency, a virtual physical quantity describing the amount of turbulence at a given position, are refactored, respectively, with neuron networks and random forests. These two functions are then coupled with the Spalart–Allmaras (SA) model to reconstitute two models for transition prediction. To demonstrate that these two coupled models provide improved prediction accuracy on transition compared with previous SA models, we conduct test cases all under a high-order weighted compact nonlinear scheme (WCNS). The prediction results of both coupled models significantly improved the capture of natural transitions occurring in the flows. Furthermore, the interpolation generalisation and extrapolation generalisation abilities of the coupled models are also demonstrated in this paper. The results emphasize the potential for machine learning as a supplementary in turbulence transition modeling.
Terminal Traffic Situation Prediction Model under the Influence of Weather Based on Deep Learning Approaches
Authors: Yuan Ligang , Zeng Yang , Chen Haiyan , Jin Jiazhi
Published: October 2022

In order to quantify the degree of influence of weather on traffic situations in real time, this paper proposes a terminal traffic situation prediction model under the influence of weather (TSPM-W) based on deep learning approaches. First, a feature set for predicting traffic situations is constructed based on data such as weather, traffic demand, delay conditions, and flow control strategies. When constructing weather data, a terminal area weather quantification method (TAWQM) is proposed to quantify various weather feature values. When constructing the traffic situation label, fuzzy C-means clustering (FCM) is used to perform cluster analysis on the traffic situation, and the traffic situation is marked as bad, average, or good. Accordingly, the multi-source data is fused as the input vector, based on the combined prediction model of convolutional neural network (CNN) and gated recurrent unit (GRU), TSPM-W is constructed. Finally, based on the historical operation data of the Guangzhou Baiyun International Airport terminal area, the proposed data set is used to predict the traffic situation time series at intervals of 1 h, 3 h, and 6 h. The comparative experimental results show that the proposed time series prediction model has higher prediction accuracy than other existing prediction methods. The proposed dataset is able to more accurately predict the traffic situation in the terminal area.
Rotating Detonation Combustion for Advanced Liquid Propellant Space Engines
Authors: Heister Stephen D. , Smallwood John , Harroun Alexis , Dille Kevin , Martinez Ariana , Ballintyn Nathan
Published: October 2022

Rotating (also termed continuous spin) detonation technology is gaining interest in the global research and development community due to the potential for increased performance. Potential performance benefits, thrust chamber design, and thrust chamber cooling loads are analyzed for propellant applications using liquid oxygen or high-concentration hydrogen peroxide oxidizers with kerosene, hydrogen, and methane fuels. Performance results based on a lumped parameter treatment show that theoretical specific impulse gains of 3–14% are achievable with the highest benefit coming from hydrogen-fueled systems. Assessment of thrust chamber designs for notional space missions shows that both thrust chamber length and diameter benefits are achievable given the tiny annular chamber volume associated with the rotating detonation combustion. While the passing detonation front drastically increases local heat fluxes, global energy balances can be achieved if operating pressures are limited to be comparable to existing or prior space engines.
Comparative Analysis of Real-Time Fault Detection Methods Based on Certain Artificial Intelligent Algorithms for a Hydrogen–Oxygen Rocket Engine
Authors: Huang Peihao , Wang Tao , Ding Lin , Yu Huhuang , Tang Yong , Zhou Dianle
Published: October 2022

The real-time fault detection and diagnosis algorithm of a liquid rocket engine is the basis of online reconfiguration of guidance and the control system of a launch vehicle, which is directly related to the success or failure of space mission. Based on previous related works, this paper carries out comparative experimental studies of relevant intelligent algorithm models for real-time fault detection engineering application requirements of a liquid hydrogen–oxygen rocket engine. Firstly, the working state and detection parameters’ selection of a hydrogen–oxygen engine are analyzed, and the proposed three real-time intelligent fault detection algorithm model design methods are elaborated again. Fault detection calculation and analysis are carried out through normal test data and fault test data. The comparative analysis results of real-time intelligent fault detection algorithm models is presented from three dimensions: detection time, fault detection, and stability and consistency. Finally, based on a correlation analysis, a comprehensive intelligent fault diagnosis model design framework is given to further solve the requirements of real-time fault detection and diagnosis engineering development of a liquid rocket engine, a complex piece of equipment.
Thermal Benefits of a Cooling Guide Vane for an Electrical Machine in an Electric Ducted Fan
Authors: Hu Xuanyang , Qian Yuping , Dong Chaofan , Zhang Yangjun , Wang Changjiang , Zhuge Weilin
Published: October 2022

Equipped with a distributed electric propulsion system, eVTOL is the primary vehicle for future urban air mobility. The electrical machine determines the weight of the distributed electric propulsion system, and the cooling capability determines the electrical machine’s weight. The electrical machine with air cooling is preferred for eVTOL due to its simplicity and light weight. This paper presents a new air-cooling system for an electrical machine in an electric ducted fan propulsion system. The novel cooling system consists of a cooling guide vane with a heat pipe (CGVHP), which is located downstream of the ducted fan rotating blade. The heated end of the heat pipe is inserted into the stator end windings and the cold end is inserted into the cooling guide vane. The heat generated in the windings is transmitted to the cooling guide vane by the heat pipe and dissipated by the forced convection using low-temperature air passing through the ducted fan. The cooling performance of the cooling guide vane with the heat pipe was numerically simulated, considering several critical design factors. The simulation results showed that the proposed CGVHP can be helpful for reducing the winding temperature of the electrical machine by over 25.5 °C at the peak power condition of 15.7 kW.