Space Aircraft Research Articles

Design and optimization of three segmented thermoelectric generator for nuclear reactor application

With the scientific exploration in deep space and deep sea, traditional fossil energy and solar energy cannot supply energy for deep space aircrafts and deep sea vehicles continuously, new energy power systems with the features of long endurance, high reliability and high energy density are imperative. Small nuclear reactor has become one of the best solutions for deep space energy demand in the future due to its strong environmental adaptability and long-life time. To improve the reliability of the static heat pipe reactor, the thermoelectric generators (TEGs) are utilized to convert fission heat into electrical energy. Focusing on the demands of improving the conversion efficiency, a new three segmented TEG is proposed based on the Bi2Te3, CoSb3 and Half-Heusler thermoelectric materials in this paper. Combined with the application requirements of heat pipe reactor, the geometric configuration such as different heights and the cross-sectional area of the three different materials in the PN legs is designed and optimized under different heat flux boundary conditions. The influences of contact electrical resistance and contact thermal resistance on the conversion efficiency have been investigated. When the contact electrical resistivity increases from 0.01 μΩ cm2 to 1000 μΩ cm2, the conversion efficiency loss increases from 2.6% to 80.1%. As the surface roughness rises from 0.1 μm to 100 μm, the conversion efficiency loss increases from 0.9% to 42.7%. Based on the heat flux boundary conditions provided by the heat pipes, the thermoelectric conversion performances of three segmented TEG under different external loads are investigated. Through the geometric optimization of the three segmented TEG with total height 20 mm, the thermoelectric conversion efficiency improves from 6.9% to 15.34%. For the simulation heat flux density conditions of 70 kW m−2, 75 kW m−2, 80 kW m−2, 85 kW m−2 and 90 kW m−2, the maximum output power of a thermoelectric generator can reach 8.56W, 9.71W, 10.85W, 12.00W, and 13.11W, respectively. The output characteristics of the three segmented TEGs meet the design demands of the static conversion system.

The role of commercialization of high technologies in scientific and production cooperation

The article reveals the role and importance of types of high-tech products, taking into account international practice, domestic official statistics and classification of goods of foreign economic activity. It is established that in some cases innovative and high-tech products are identified. It is revealed that currently the most high-tech is the production of basic pharmaceutical products and pharmaceuticals, biotechnology, the production of computers, electronic and optical products; production of various air and space aircraft. The key regional leaders in the production of high-tech products in the world by region are considered. Based on the results of the consideration of the content of the concepts “innovation” and “technology”, “commercialization of innovations” and “commercialization of high-tech products”, the author’s vision of interpretations is proposed, with the justification that innovativeness actually acts as an additional feature of high-tech products. A study of the types of commercialization of high-tech products was conducted, according to the results of which the author’s classification was proposed according to the content, level of efficiency, number of subjects of commercialization, geographical coverage of subjects of commercialization and methods of financing.

Pengaturan Tentang Penerbangan Komersial Dan Tanggung Jawab Negara

Introduction: In transportation activities, the risk of an accident is an unavoidable thing so that unification of arrangements regarding this matter is an absolute thing to do.Purposes of the Research: This study aims to find out and examine how the regulation regarding the flight of commercial aircraft in the air space of a country is reviewed from international law and how the form of state responsibility when a commercial aircraft is shot down is reviewed from international law Methods of the Research: This writing uses a normative type of legal research, which is carried out by studying theories, concepts, legal principles, and laws and regulations. In this study, the author used 2 approaches, namely the statutory approach, and the case approach.Results of the Research: The results showed that the International air law Regulation related to the parties' obligation to regulate the safety of commercial flights crossing its airspace must be in accordance with the Chicago Convention of 1944. These arrangements are made so that flights that cross the airspace of other countries can be kept safe and secure. Iran's shooting down of Ukrainian plane PS752 has violated provisions in the 1944 Chicago Convention on its airspace in an armed dispute. Therefore, Iran must take responsibility for this incident. In the future, firmness and increased cooperation with various parties are needed so that safety and security in international flights and national flights can be achieved.

Инновационные технологии повышения производительности и качества механической обработки полимерных композиционных материалов

An urgent problem for improving the efficiency and machining operation quality for new polymer composite materials (PCM) based on carbon fiber in the operation of rocket and space equipment and aircraft engineering parts is solved in the article. One of the breakthroughs of the Russian domestic engineering is the introduction of wing elements of the new MS-21 civil airliner, the production of noise suppression bodies, compressor blades and other parts of gas turbine engines made of carbon fiber, requiring high-quality and productive machining. Machining operation of these products involves difficulties caused by the requirements of the design documentation to ensure the necessary degree of roughness, soundness of the machined surface and high strength of the finish-machined component. This article presents the results of a study of the application of high-performance technology of sequential blade-abrasive processing of carbon fiber-based PCM products. This article presents the results of a study of the application of high-performance technology of sequential blade-abrasive operation of carbon fiber-based PCM products. The rational geometry of the blade cutting tool for primary machining of the PCM is determined. An adequate empirical mathematical model of cutting modes influence on the surface layer roughness in the milling operation has been developed, as well as rational processing modes have been determined.
 The results of experimental studies of the abrasion of PCM with rigid grinding wheels made of white electrocorundum, green silicon carbide and elborum are presented. The dependences of the surface layer roughness on the grinding modes are given. According to the research results and the developed mathematical model, the rational characteristics of grinding wheels and processing modes are determined. For the first time, the issues of the influence of machining defects on the strength of PCM are viewed. Comparative tensile and tear strength tests of samples made by traditional edge cutting machining and sequential edge-cutting-abrasive operation are presented. The increase in tensile and tear strength of PCM parts manufactured according to the technology of sequential edge-cutting-abrasive operation by 20.30% compared to traditional edge-cutting operation has been proved.

Mathematical modeling of movement of multi-rotor type aircraft

The problem of determining the features and setting the problem of mathematical modeling of multirotor aircraft (LA) is considered. Differences of their mathematical models from the classical mathematical models of aircraft and single-rotor helicopter type aircraft are considered. The analysis and substantiation of the forces and moments acting on a multirotor aircraft are carried out, taking into account the peculiarities of considering the corresponding coordinate systems necessary for studying the spatial motion of the aircraft. The problem of controlling the trajectory motion of an aircraft is formulated taking into account the rotation of its structure around the center of mass. Based on the consideration of the structural diagram of one of the most common four-rotor aircraft (quadcopter), a scheme for creating control forces and moments acting on the aircraft, under the influence of which the aircraft’s trajectory in space changes, is substantiated. The main mathematical dependences characterizing the kinematics of the motion of a multi-rotor aircraft are given. On the basis of the analysis carried out, a generalized block diagram of the control process for such an aircraft is substantiated and presented. To test the performance and adequacy of the mathematical model, a study was made of the movement of a quadrocopter in a vertical plane between given points in space in accordance with the law of forced control, which ensures the movement of an aircraft in space with maximum speed. The computer simulation of the obtained analytically mathematical dependences showed that this approach is applicable to the construction of mathematical models of the motion of multirotor type aircraft of various design layouts.

Preface

The International Conference on Aerospace, Aerodynamics and Mechatronics Engineering has been successfully held two times, and has attracted various promising researchers who are developing new directions in the field of aerospace, aerodynamics and mechatronics engineering.The 2023 2nd International Conference on Aerospace, Aerodynamics and Mechatronics Engineering (AAME 2023), held in Beijing, China from April 21st to 23rd, 2023, is meant to unite researchers, experts, professors and academic staff as well as a wide range of participants of professional community from China and other countries concerned. AAME 2023, with more than 100 participants, was held to further enhance aerospace technology and its application as well as the potential business or research contact among all the participants.The highly eventful program of the Conference, the list of well-established organizations-participants and devoted engagement of many colleagues throughout all the stages of the Conference’s preparation instill confidence in practical importance of mutual initiative. The framework of the Conference comprises keynote speeches, oral presentations, and academic investigation, discussing open and significant problems facing aerospace, aerodynamics and mechatronics engineering, proposing innovative ideas and approaches to solution of the problems, and considering new possibilities of application and development of cutting-edge aerospace technology.The Conference has become one of the venues for demonstrating scientific achievements of international class by leading scientists and young scholars and would facilitate the strengthening of academic cooperation, meanwhile the Conference proceedings would be expressed in the form of international scientific publishing. Various topics of the papers, gone through a vigorous peer review process, are covered in the proceedings, including: Rocket Theory and Design, Developments in New Space Communication Techniques, Aircraft Navigation and Positioning Technology, Microelectronics Manufacturing Engineering Signal Processing, Vacuum Electronic Technology, etc.On behalf of the Conference Organizing Committee, we would like to thank the referees for their efficient and thoughtful actions. We are grateful to the members of the Technical Program Committee for their efforts in making and shaping the program for AAME 2023. Particularly, we acknowledge the publishing support from the members of Journal of Physics: Conference Series.We hope that the future AAME will be as successful and stimulating, as indicated with the contributions presented in this volume.The Committee of AAME 2023List of Committee Member is available in this pdf.

Ceramics Based on Reaction-Bonded Boron Carbide for Heat Protection Coatings of Space Aircraft

Ceramics Based on Reaction-Bonded Boron Carbide for Heat Protection Coatings of Space Aircraft

Measurements and analysis of solar spectrum in near space

The experiment for measuring the solar spectrum at different latitudes and altitudes was conducted to obtain a suitable Air Mass Zero (AM0) standard solar cell calibration strategy with high altitude balloon flight calibration method. This is the world’s first acquisition of solar spectrum data at an altitude of 35 km using high-altitude balloon platform. The solar spectrum at the upper boundary of the atmosphere was measured and the spectral distribution was obtained from 20 to 35 km during the ascent. The results show that spectral distribution at 35 km is almost equivalent to that of AM0, the peak irradiance at 35 km is close to that of AM0, and the highest peak of this spectrum is at 450.2 nm. Comparing the results taken at different altitude, the effect of ozone, oxygen and water vapor is clearly seen. The measurement methods and results discussed in this paper can assist in verifying the accuracy of space solar cell calibration using high-altitude balloons. It could also provide a reference for the design of photovoltaic energy systems for near space aircrafts. Finally, the results taken from the launch site may be of use for the air quality monitoring and the design of photovoltaic system used in ground-based solar power generation in the Qinghai-Tibet Plateau.

Microstructural Evolution and Mechanical Properties of Ti2AlNb/GH99 Superalloy Brazed Joints Using TiZrCuNi Amorphous Filler Alloy

Dissimilar materials brazing of Ti2AlNb alloy to GH99 superalloy is of great pragmatic importance in the aerospace field, especially the lightweight space aircraft components manufacturing. In this work, TiZrCuNi amorphous filler alloy was used as brazing filler, and experiments were carried out at different brazing temperatures and times to investigate the changes in interfacial structures and properties of the joints. The typical interfacial microstructure was Ti2AlNb alloy/B2/β/Ti2Ni (Al, Nb) + B2/β + (Ti, Zr)2(Ni, Cu) + (Ti, Zr)(Ni, Cu)/(Cr, Ni, Ti) solid solution + (Ni, Cr) solid solution/GH99 superalloy when being brazed at 1000 °C for 8 min. The interfacial microstructure of the joints was influenced by diffusion and reaction between the filler alloy and the parent metal. The prolongation of brazing process parameters accelerated the diffusion and reaction of the liquid brazing alloy into both parent metals, which eventually led to the aggregation of (Ti, Zr)2(Ni, Cu) brittle phase and increased thickness of Ti2Ni (Al, Nb) layer. According to fracture analyses, cracks began in the Ti2Ni (Al, Nb) phase and spread with it as well as the (Ti, Zr)2(Ni, Cu) phase. The joints that were brazed at 1000 °C for 8 min had a maximum shear strength of ~216.2 MPa. Furthermore, increasing the brazing temperature or extending the holding time decreased the shear strength due to the coarse Ti2Ni (Al, Nb) phase and the continuous (Ti, Zr)2(Ni, Cu) phase.

DEVELOPMENT OF A SIMULATION MODEL FOR REGULATION OF THE ANGLE OF ROLL OF A QUADCOPTER USING A PID CONTROLLER

Autopilot systems typically consist of an “inner loop” that provides stability and control, as well as an “outer loop” that handles mission-level objectives such as waypoint navigation. Unmanned aerial vehicle (UAV) autopilot systems are predominantly implemented using a control system with proportional, integral, and differential controllers that have demonstrated accuracy under stable conditions. A simulation model of the angle of roll of a quadcopter based on a PID controller was developed and investigated. The model reflects in two-dimensional space of the angles of inclination of the quadcopter. Several methods for calculating the coefficients of PID controllers are considered and the choice of the optimal one for solving the set task is made. Simulation modeling was carried out to stabilize the quadcopter in roll. For this purpose, a JavaScript page with a virtual quadcopter was written. The constructed simulation model allows you to visually evaluate the oscillations of the aircraft in space, which significantly reduces the time and cost of setting up the PID controller.

МОДЕЛЬ РУХУ БЕЗПІЛОТНИХ ЛІТАЛЬНИХ АПАРАТІВ НА ОСНОВІ АЛГЕБРИ ДУАЛЬНИХ КВАТЕРНІОНІВ

The widespread use of unmanned aerial vehicles during warfare has intensified the problem of their management, especially when they are used in large groups. One of the main tasks is to ensure coordinated movement of the group's aircraft in space. Optimizing the movement of each device of the group in three-dimensional space is expedient to use mathematical models. The movement of any unmanned aerial vehicle can be presented as a combination of translational and rotational movements, and its speed as a combination of translational and rotational velocities. Previously, these movements were modeled separately using a system of differential equations or quaternions. In this article, a mathematical model of rotational and translational movements of an aircraft based on the algebra of dual quaternions is developed. Dual quaternions consisting of eight scalars are a compact representation of rigid transformations in space. Therefore, their properties determine the advantage in the course of motion simulation, as they reduce the amount of calculations. Thus, with the help of one dual quaternion, it is possible to provide both translational and rotational motions at once, and the operation of non-commutative multiplication of dual quaternions is used to simulate the movement. The model assumes that the real part of the dual quaternion determines the orientation of the UAV in space, and the dual part determines its position in three-dimensional space. In order to connect aircraft coordinate systems with the model, expressions for the transition from aircraft orientation angles (roll, yaw, and pitch) to dual quaternion parameters and vice versa are obtained. The functionality of the proposed model was confirmed using the developed software for modeling the coordinated movement of aircraft. The software is adapted for graphical display of a large number of aircraft in web browsers with WebGl support. Keywords: motion modeling; rotational and translational movement; unmanned aerial vehicles; quaternions; dual quaternions; algebra of quaternions.

Magnetorheological Finishing of Chemically Treated Electroless Nickel Plating

Electroless nickel plating with a nanofinished surface is used in space mirrors, automobile parts, aircraft components, optical instruments, and electronic equipment. Finishing of these components using conventional finishing techniques is limited due to size, shape, material, and process constraints. This work reports the nanofinishing of electroless nickel-plated surfaces using a magnetorheological finishing process where the surfaces are pre-treated with chemicals. The chemicals used in this work are hydrogen peroxide (H2O2) and hydrofluoric acid (HF). The effect of exposure time and concentration on the microhardness and roughness is studied to understand the surface chemistry after chemical treatment. The hydrogen peroxide forms a passivated layer, and it helps in easy material removal. Hydrofluoric acid improves surface quality and also helps in the removal of contaminants. The finished surface is characterized to understand the effect of chemical treatment on the finishing rate and surface topography. Normal and tangential forces are mainly affected by the hardness and surface condition after the chemical treatment. The best combination of parameters (chemical treatment with 1% HF for 30 min) was obtained and finishing was carried out to obtain a nanofinished surface with its areal surface roughness (Sa) reduced to 10 nm.

Radiation‐Tolerant Electronic Devices Using Wide Bandgap Semiconductors

AbstractThe aspiration of electronic technologies that are resistant to high‐energy cosmic radiation is essential for current harsh radiation environment exploration. Integrated circuits mostly require post‐processing after designing, making their structures more complex than the standard systems. Thus, unique designs and strategies are developed to enable the high tolerance of space electronics to radiation in nuclear and avionic applications. The wide bandgap semiconductor (WBG) materials with excellent electronic/optical properties and structural stability are appealing options for radiation‐immune applications. Here, in this article, the development and fabrication of various electronic devices have been reviewed using different wide bandgap materials for radiation‐hardened applications. Detailed investigations are discussed, from the fundamental wide bandgap materials withstanding limited irradiation to the development processes of the electronic devices used in harsh environments. Furthermore, the challenges and future perspectives of the WBG‐based radiation harsh electronic devices are also highlighted in this review with commercial application in space stations and aircraft.

Extended state observer based robust control of electrical cylinder heavy-load start

Aerospace erection system is applied to space aircraft launching platform, driving space aircrafts from horizontal position to vertical position. Its performance directly determines the reliability, stability and rapidity of launching platform. Electric cylinder has the advantages of high environmental adaptability and high control accuracy, which is gradually used as the actuator in erection system. However, due to the large weight of aircraft, it is difficult to prevent the load from slipping while starting. In this paper, a robust controller is proposed for horizontal position heavy-load start control. Firstly, a control model of a high-power electric cylinder with multiple servo motors in parallel is put forward. After that, based on the backstepping method, in order to suppress the effect of parameter variation, a robust feedback term is designed. In addition, since the external disturbances of the system are difficult to measure, system disturbances are estimated using an extended state observer and incorporated into the controller through feedforward compensation. In the formulated nonlinear control process, parameter change error and noise interference are considered. The controller theoretically guarantees a stable starting process, which is expected to provide a safe and reliable control method for electric cylinder system.

Approach and Landing Aircraft Wake Encounter Risk Based on Reynolds-Averaged Navier-Stokes Numerical Simulation

In order to shorten the wake safe separation, numerical simulation technology with aerodynamic response models and strip models have been combined to calculate wake hazard zone. As a realistic case, a medium aircraft ARJ21 following a heavy aircraft A330-200 is considered, and the Reynolds-averaged Navier-Stokes (RANS) method is used to explore the wake vortex evolution process of the leading aircraft at the decision height. A strip algorithm is proposed to calculate the rolling moment coefficient and overload increment of the ARJ21 after encountering the wake of the front aircraft in the three-dimensional space. The proposed algorithm identifies the area where the wake of the front aircraft can cause risks to the following aircraft and analyzes the evolution process of the hazard zone of the section where the decision height is located. The minimum safe separation of the ARJ21 following the A330-200 is 1.32 nmile, which is 26.4% of the ICAO separation standard of 5 nmile. When the average runway occupancy time (ROT) is reduced to match the separation of 1.32 nmile, the capacity of runway 02R/20L in Tianfu International Airport could theoretically reach 102.37 sorties/h under this aircraft pair combination. Compared to original 27 sorties/h, the runway capacity can be improved up to 279.14%, which will increase the airport operation efficiency.

Review of Vent Systems of Space Vehicle, Spacecraft and Aircraft

The main focus of the review article is to present the vent system of space vehicle and spacecraft. Quasi-one dimensional, quasi-steady and isentropic analytical and computational fluid dynamics equations are employed to compute differential pressure inside the compartment. Discharge characteristics of vent system depend on geometry, location of vent and external environment. An inverse analysis is performed to estimate the discharge coefficient using measured and computed compartment differential pressure time history. The reconstructed differential pressures of the compartment are compared with pre- and post-flight data. The differential pressure and the rate of pressure drop in the compartments are analysed via isentropic equations. A numerical scheme based on compressible gas dynamics relation is discussed for pressurization of aircraft cabin. The vent valve with a spring loaded butterfly valve can be evaluated using the isentropic relations.

DUG Insight: A software package for big-data analysis and visualisation, and its demonstration for passive radar space situational awareness using radio telescopes

As the demand for software to support the processing and analysis of massive radio astronomy datasets increases in the era of the SKA, we demonstrate the interactive workflow building, data mining, processing, and visualisation capabilities of DUG Insight. We test the performance and flexibility of DUG Insight by processing almost 68,000 full sky radio images produced from the Engineering Development Array (EDA2) over the course of a three day period. The goal of the processing was to passively detect and identify known Resident Space Objects (RSOs: satellites and debris in orbit) and investigate how radio interferometry could be used to passively monitor aircraft traffic. These signals are observable due to both terrestrial FM radio signals reflected back to Earth and out-of-band transmission from RSOs. This surveillance of the low Earth orbit and airspace environment is useful as a contribution to space situational awareness and aircraft tracking technology. From the observations, we made 40 detections of 19 unique RSOs within a range of 1,500 km from the EDA2. This is a significant improvement on a previously published study of the same dataset and showcases the flexible features of DUG Insight that allow the processing of complex datasets at scale. Future enhancements of our DUG Insight workflow will aim to realise real-time acquisition, detect unknown RSOs, and continue to process data from SKA-relevant facilities.

Microelectromechanical Gyrovertical

Gyroscopic verticals (gyroverticals) are designed to determine the direction of the true vertical on moving objects. Being one of the devices of the orientation system of a moving object, they are used as sensors for the roll and pitch angles of an aircraft (or sensors of similar angles for other moving objects) and serve to create a platform stabilized in the horizon plane on a moving object. The electrical signals taken from the measuring axes of the device are used in flight, navigation, radar systems, visual indicators, etc. Gyroscopic stabilization systems are widely used as the basis of integrated management systems on aircraft and miniature unmanned aerial vehicles for generating signals proportional to the angular deviations of the aircraft in space in terms of roll and pitch angles and for stabilizing and controlling the position in space of optical equipment. At present, sensors based on the technologies of microelectromechanical systems are widely used in small aircraft. Their important advantage is small weight and size characteristics, and the main disadvantage is low accuracy. Such sensors are used in navigation systems and automatic control systems of aircraft. In particular, algorithms for calculating the orientation angles of an unmanned aerial vehicle are known, using information from microelectromechanical angular velocity sensors. However, due to large drifts, an error accumulates in time and, as a result, the operating time is limited.

Prototype of Mobile Meter Waveband Radar with Improved Functionality

Actual stage of meter waveband radar evolution is the design of mobile radar with improved surveillance functions, as well as signal generation and processing. Such radars measure coordinates of aircraft in 3D space with adaptive change of operation frequency, parameters of probing signal, and polarization. Except radiolocation tasks, such radars allow to carry out integral information processing, EM analysis, ELINT, as well as jamming and clutter canceling, and must have height mobility and secrecy properties. The achievement of these properties is possible due to the application of digital antenna arrays with digital solid-state Tx/Rx modules, modular construction of all radar subsystems, digital beamforming technology, adoptive algorithms of space-time, and statistical processing of received signals. The prototype of meter-wavelength band radar system with height effectivity and informativity of radiolocation receiving, with the capability of fast moving and deploying is review in this article. The proposed radar system allows to provide measuring coordinates of an aircraft in 3D space, large distance detection, tracking and targeting of all types of aircrafts (including stealth aircrafts), carry out integral processing of radiolocation information, ELINT, EM analysis, as well as jamming and clatter canceling.

Determination of coordinates of unmanned aircrafts by means of kinematic projection

A methodology for determining the mechanical trajectory and spatial coordinates of unmanned aircrafts by means of kinematic projection is described. The suggested methodology consists in the formation of two moving independent centers of kinematic projection by launching intercepting drones into space. Electromagnetic radio waves emitted by unmanned aircrafts pierce an unknown flying object and generate two independent projecting rays intersecting at the place of searching a flying object. At that, the instantaneous (at a certain moment) projection of the point of spatial location of the searched object will be located in an imaginary `picture plane' on the line connecting the projections of the points created by projecting rays of the intercepting drones. Since all the objects of projection are mobile in this case, the whole projection of the trajectory of the searched object will be displayed on the operator's monitor. The formation of a `more picture-like plan' perpendicular to the main one will allow us to build an axonometric view not only for the projection, but directly for the aircraft spatial movement trajectory. Every point of this trajectory gives us information about `instant' coordinates of the location of the aircraft in space. Velocity is calculated as the ratio of spatial displacement of a flying object to the duration of movement. The scientific novelty of the method of determining the trajectories, velocities, and coordinates of an unmanned aircraft consists in the combination of radar detection of a moving object with kinematic design used for its implementation in order to calculate instantaneous coordinates of the object. This methodology solves the problem of determining more accurately the coordinates of flying objects that are not clearly and qualitatively displayed on radar monitors due to small size, mass, and specific materials used in manufacture. At the same time, the influence on the accuracy of determining the coordinates of unmanned aircrafts reflected from the fixed obstacles placed on the relief surface of earth was established. The results of this study can be used in practice in military science, for example, during the anti-terrorist operation in the occupied territories of Ukraine, with the aim to detect and neutralize enemy reconnaissance unmanned aircrafts. The use of this method in aerial photography for clear fixation of drone coordinates during aerial surveys for terrain topography is also promising.