Subsystem Design Research Articles

BIM and Mechanical Engineering—A Cross-Disciplinary Analysis

Mechanical Engineering (ME) includes the design, manufacturing, assembly, and maintenance of mechanical subsystems for Architecture, Engineering, Construction, and Owner-Operator (AECO) projects. The intense adoption of information and communication technology in the AECO started with building product modelling, which was originally pioneered in the ME domain (i.e., automotive industry). The complexity and limited openness of product models paved the way for Building Information Modelling (BIM). Today, BIM workflows require an exchange of interoperable architecture, structure, and MEP/HVAC models and their seamless integration into a shared BIM model. Many specialized ME systems exist (i.e., medical gases and vacuum) for which BIM is not mature enough and where the role of BIM has not yet been studied. Therefore, a comprehensive cross-disciplinary analysis on the mutual influence of the BIM and the ME domain is needed for researchers and professionals. It identifies research fields and trends at the intersection of BIM and ME and analyzes their scope, limitations, and requirements for future extensions of BIM for better integration with ME. The analysis is based on an extensive literature search considering the interdisciplinary nature of ME. The initial collection of papers has undergone a rigorous bibliometric analysis that used a text mining approach for validation. Results show the field “Industry 4.0” as the most prosperous BIM influencing research field, followed by “Energy optimisation” and “Environmental Product Declaration”, while identifying “Geometric optimisation” and “Reinforced material” as the trendiest. Finally, conclusions on the impact of BIM on ME were drawn and 11 research opportunities were identified. This paper provides directions for studies where research is focused on the integration of ME systems in BIM workflows and on the extension of BIM capability to model future ME systems.

A Multi-Index Feedback Linearization Control for a Buck-Boost Converter

Due to the nonlinear and nonminimum phase characteristics of the buck-boost converter, the design of its controller has always been a challenging problem. In this paper, a multi-index feedback linearization control strategy is proposed to design the controller of the buck-boost converter. Firstly, by constructing an appropriate output function, the original nonlinear system is mapped into a combination of a linear subsystem and a nonlinear subsystem. Then, according to the structural characteristics of these two subsystems, the linear optimal control theory is adopted for the control design of the linear subsystem to make it have a good output performance, while for the nonlinear subsystem, the coefficient of the output function is adjusted to ensure its stability. Finally, based on the Hartman–Grobman theorem, the internal mechanism and coefficient adjustment basis of the proposed method are revealed; that is, by adjusting the coefficient of the output function and the feedback coefficient of the linear control law, the poles of the system are configured to achieve the purpose of adjusting the static and dynamic performance of the system. The simulation results show the feasibility and superiority of using the multi-index feedback linearization control strategy to design the nonlinear control law of the buck-boost converter.

WITHDRAWN: Parametric analysis of schematic for efficient sub-system design with MOSFET’s scaling factors

Abstract Integrated Circuits (IC) focus on low power devices, as per the demand in industries. In VLSI circuits, for modern applications, power dissipation is an essential constraint as it plays a crucial role in the system’s overall performance estimation. Many techniques, like power gating or clock gating, can be used to reduce unnecessary power consumption. Non-working parts would be switched off during the non-functional period. IC designers are still facing the problem of choosing the best logic among different styles for the set of user-defined constraints. It is easy to select the optimal, with the prior availability of metrics, to make the design efficient. In this paper, the analysis was done on Mentor Graphics EDA Tool with 130nm technology to predict the characterization of given logic with multiple scaling factors and tested through distinct voltages by continuously changing MOSFET dimensions. The clocked CMOS is like CMOS in some conditions at the cost of power dissipation (196.49uW in CCMOS and 100.24nW in CMOS). Pseudo nMOS is suffering from delay variations (with 117.97pS to 503.74 pS) by changing MOS size and input voltage in their characteristics, unlike CMOS logic. It is to notice that the CMOS and clocked CMOS logics are ideal in maintaining constant delays in response to change in FET dimensions or supply voltages. Similarly, pseudo-NMOS logic, otherwise, is a delightful choice to use (with an average power maximum of 108.54 nW) when a constant power dissipation is mandatory from the system even, it’s far operated in vibrant conditions. Identified efficient schematic which is either essential to arrive the most effective sub-system, which in turn increases the overall system performance.

Advancing DSP into HPC, AI, and beyond: challenges, mechanisms, and future directions

Digital Signal Processors (DSPs) have been widely used in embedded domains, delivering high performance with ultra-low power consumption. Such promises make it attractive for more domains that DSP was not an option before. To show how DSP lives up to these promises, we review two milestone DSPs: FT-Matrix and FT-Matrix2, which are designed by National University of Defense Technology with the purpose of advancing DSPs into the era of higher performance computing, AI, and even beyond. We demonstrate that the key challenges lie in the orchestration of huge computation resources and efficient data supply sub-system design. We show the key mechanisms in both FT-Matrix and FT-Matrix2 targeting these challenges, and also come up with possible future directions for enabling DSPs for a wider scope of applications.

Simplified and Precise Design of Crossflow Turbine Power Transmission Components

Despite the merits of small hydropower (SHP), coupled with the perennial inadequate and unreliable electricity supply in SSA, the huge SHP potential in the region is hugely untapped. This is largely attributed to the lack of adequate technical components for the development of SHP turbines, which are: technical personnel, and production facilities in the region. The hydraulic power possessed by flowing water in SHP resources can be harnessed and transformed into usable electrical energy via the deployment of a hydro turbine plant. Commonly used hydro turbines include crossflow (CFT), Pelton, Turgo, and Francis turbines. Amongst these turbines, CFT is mostly applied in low head sites and has efficiency ranging from 70–85%. The CFT power transmission subsystem is considered vital to its performance; the shaft, which transmits the generated motion to drive the alternator, is the most critical part of the CFT transmission subsystem and it requires careful design and production processes. This study centres on the development of a simplified systematic design process for power transmission shaft, pulley, and belt, to facilitate CFT power generation efficiency. .Further, the study is geared towards boosting CFT technology capacity domestically for the benefit of local production. The hydrological properties of the Ayiba SHP site in Osun state, Nigeria, were adopted for this work as a case study. The head and power for this resource are 11.8 m and 122.4 kW, respectively, and are served as the fundamental parameters for the design of the power transmission subsystem. The design computation shows that a shaft of diameter 65 mm and a D-type of V-belt with a corresponding pulley will be required to transmit the generated turbine power to the alternator. A 3-D model was created based on the design values and this was used to validate the integrity of the shaft by static stimulation. The simulation result, which is based on von Mises was satisfactory as the highest stress obtained in the shaft was 205 N/mm2; resulting in a 2.6 factor of safety.

РАЗРАБОТКА КОНЦЕПЦИИ ДВУХФАЗНОЙ СИСТЕМЫ ТЕПЛООТВОДА СПУТНИКА

For spacecraft (SC) with power unit capacity more than 4 ... 6 kW promising construction of thermal control system (TCS) based on two-phase mechanically pumped loops (2PMPL). The development of 2PMPL has been carried out quite intensively since the early '80s. However, so far there are no examples of practical implementation of such high-power systems. One of the main reasons mentioned is the novelty of the system, and insufficient study of its operation in space conditions, which adds risks. The most important component of such systems is a heat rejection subsystem (HRS), whose task is to reject heat from the coolant and radiate it into space. In its turn, HRS is also a system, the design of which requires using a system approach, considering various aspects of its operation. HRS includes a heat-hydraulic network and a radiation heat exchanger (RHE). The key elements of the HRS are condensers (CC), quite new devices for space technology. This paper presents an algorithm for the design and optimization of the heat rejection subsystem (HRS) of a satellite two-phase thermal control system. The methodology of engineering synthesis of complex technical systems and informal procedures for multi-criteria optimization of elements and subsystems at various stages of HRS design is repeatedly used. t is shown that optimization should be carried out both at the level of elements and subsystems, and at the level of the whole thermal control system. As a result of the study, the HRS design is proposed, which uses condensers in the form of smooth steel tubes of constant cross-section and their series-parallel connection scheme in the hydraulic network. Main advantages of the design: traditional for single-phase loops elements are used; operation of elements and subsystems in zero gravity conditions is predictable and allows complete testing on the ground without mandatory flight experiment; the system is operable at high saturation pressures (temperatures) (on ammonia - up to 85℃).

Requirement derivation of vehicle steering using mechanical four-poles in the presence of nonlinearities

In a recent companion publication, we developed the basic theory for deriving requirements for the dynamic properties of vehicle components. These requirements correspond to targets at vehicle level, but they address stand-alone subsystems being developed simultaneously by different parties. For this purpose, the vehicle, i.e., the coupled system, is divided into subsystems such as the steering and the front axle. The substructuring method used for this was based on the four-pole theory, where frequency-dependent transfer matrices are needed. Thereby, the relevant transfer coefficients of each subsystem were assumed to be linear.In this work, the method is extended to cope with nonlinear behavior of the subsystems. The basic idea is to characterize the nonlinear systems in the frequency domain by their mono-harmonic responses depending on the force level acting at their input. Both virtual and experimental methods can be used to identify the target-relevant four-pole model of the steering and the front axle. To consider nonlinearities in terms of amplitude-dependent behavior, each subsystem is investigated at multiple amplitude levels. As a main difference to the companion publication, the results are not limit curves, but rather limit surfaces in terms of the dynamics of each subsystem over frequency and force amplitude, which serve as envelope to subsystem design. Iterative algorithms are proposed to make the linear four-pole method still applicable to problems with this kind of nonlinearity where higher harmonics resulting from the nonlinearities can be neglected.

Application of Big Data Information System in the Field of Public Utilities Management

With the continuous development of information technology, the management of social issues has entered a new era, and a series of management activities in the field of public service management are also facing new issues. Based on the above background, the purpose of this article is the application of big data information system in the field of public utilities management. This article first discusses the relevant theories of public information resources, including the concepts of public information resources, public information resource integration, public information big data platform, etc., and summarizes and summarizes them; secondly, it focuses on the current status of the integration and application of public information resources And the existing problems, and analyzed the advantages of using big data technology to promote the integration and application of public information resources; then, combining the current status of the integration and application of public information resources and the actual needs of the construction of public information big data platforms, the positioning of the public information big data platform is explained. And the construction content, built the overall construction framework of the public information big data platform, and carried out the functional analysis and design of the various subsystems of the platform; finally, discussed the performance evaluation index system of the public information big data platform, using the analytic hierarchy process and fuzzy The comprehensive evaluation method builds a public information big data platform performance evaluation model. When the number of folds is 2, its prediction accuracy is the highest, reaching 96.91%, which evaluates the construction and operation of the platform.

Design and Fabrication of 3-Axes Mini CNC Milling Machine

The main aims of the current work are to explore the theoretical and technical procedures for design, fabricate, assembly, and testing of the electromechanical subsystems for developing a high precision cost-effective mini three-axis vertical CNC milling machine with an easy interface, high speed, less power consumption, safety and durable for rapid prototyping machining, small parts and engraving small features in the electrical and medical industry. The new Mach3mill G-Code CAD/CAM software package runs on a PC and turns it into a very powerful and economical machine controller. The 3Axis CNC driver board type Kit TB6560 was used as a micro-stepping drive for the smooth drive of the selected stepper motors. The fabricated prototype CNC milling machine with an easy interface that can interpret standard G-M codes. The fabricated machine router was tested and calibrated to determine its accuracy in different position modes for surface flatness, axes perpendicularity, and several geometric accuracies such as positioning, straightness under specific tool paths, and feed rate. The results misalignment lay around +0,01 and -0,01 mm. This means that the fabricated prototype machine movements contain 0.13° tilting on X-axis and 0.22° tilting on Y-axis. After comparison and making the required improvements in both electrical and mechanical design, the machine is in a position to milling a complex contour on soft metals with considerable accuracy and speed.

Research and design of data communication subsystem of urban rail transit CBTC system

With the intensive development of urban rail transit in China, urban rail transit has increasingly become the preferred mode of transportation for citizens due to its convenience and speed. The design and construction of an efficient and highly reliable urban rail transit system has become an urgent requirement for urban rail transit construction. This article mainly introduces the research and design of the data communication subsystem of the urban rail transit CBTC system, and intends to provide some ideas and directions for studying the data communication subsystem of the urban rail transit CBTC system. This article uses a variety of methods, such as consulting literature and information research on trademark system suppliers. The development status of CBTC system and data communication subsystem is analyzed, and the importance of data communication subsystem and the necessity of the entire CBTC system are analyzed. The experimental results of this article show that in the design, development and application engineering of the CBTC system, the DCS subsystem accounts for 55%, the system is complex, and the environment is changeable, occupying an important position. When the DCS has a problem, it may cause drive failure, affect normal functions, cause greater losses, and even cause huge safety accidents. Therefore, the reasonable, reliable and safe design of the DCS subsystem is of great significance.

System Analysis and Design of the Geostationary Earth Orbit All-Electric Communication Satellites

With the help of gathered data and formulas extracted from a previous conference paper, the all-electric geostationary Earth orbit (GEO) communication satellite statistical design was conducted and further studied with analytic hierarchy process (AHP) and technique for order of preference by similarity to ideal solution (TOPSIS) methods. Moreover, with the help of previously determined system parameters, the orbital ascension, orbital maintenance and deorbiting specifications, calculations and simulations were persuaded. Furthermore, a parametric subsystem design was conducted to test the methods reliability and prove the feasibility of such approach. The parametric subsystem design was used for electrical power subsystem (EPS), attitude determination and control system (ADCS), electric propulsion, telemetry, tracking and control (TT&C) in conceptual subsystem design level, which highly relies on the satellite type and other specifications, were concluded in this paper; other subsystem designs were not of a significant difference to hybrid and chemical satellites. Eventually, the verification of the mentioned subsystems has been evaluated by contrasting the results with the Space mission engineering: the new SMAD, and subsystem design book reference.

Holistic simulation for integrated vehicle design

A holistic vehicle simulation capability is necessary for front-loading component, subsystem, and controller design, for the early detection of component and subsystem design flaws, as well as for the model-based calibration of powertrain control modules. The current document explores the concept of holistic vehicle simulation by means of reviewing the current trends in automotive system design and available solutions in terms of model interfaces and neutral modelling environments. The review is followed by the presentation of a Simulink-based multi-disciplinary modelling environment (MME) developed by the authors to accommodate simulation work across the vehicle development cycle.

Potrebne mogućnosti razornog projektila za sistem aktivne zaštite

Concept of an active protection system on combat vehicles with high-explosive fragmentation interceptor projectile is presented in this paper. Development process and characteristics of the active protection system are highly dependent on performance characteristics of an interceptor projectile. The interceptor projectile generating frontal spray of steel spherical fragments was considered. The research on design features of contemporary rocket-propelled anti-tank projectiles was done in order to define required capabilities of the projectile for active protection systems. Vulnerability of an anti-tank projectile was analyzed according to its dimensions and design of main subsystems. Representative models of different types of anti-tank projectiles were considered for vulnerability assessment. Results of minimal fragment number density and minimal impact velocity are presented and the most significant conclusions are made.

Dizajn i kompjuterska simulacija automatski kontrolisanog hidromehaničkog sistema za proizvodnju elemenata sita sa klinastim žicom

The article presents a design of mechatronic system used for the production of wire elements used in looped wedge wire screen manufacturing. Details related to the design of the hydromechanical subsystem, the control subsystem, as well as the simulation of the operation process of the entire system are presented

Control system design for steering and depth subsystems of autonomous underwater vehicle

This work seeks to propose the development of a classical-optimized control design scheme for the steering and depth subsystems of autonomous underwater vehicle. Linearization methodological approach is carried out for acquiring the transfer functions to design the convenient P/PD/PID controllers where the gains are optimally adjusted utilizing a graphical tuning technique in LabVIEW. A low pass filter with additional alpha tuning parameter is combined with the derivative action to suppress the expected oscillations entirely. Furthermore, a comparative analysis study with linear quadratic regulator optimal control is established for testing and evaluating the suggested design approach. The effectiveness of the addressed controller strategy is appraised for compensating and rejection of several uncertainties such as fin saturation, angle limitation and sensor measurements noise as they are potentially affecting the system response. The validity of the linearized classical-optimized control design is substantiated with the nonlinear underwater vehicle model through a waypoint guidance scenario under LabVIEW simulation platform. The results revealed a significant improvement in transient and steady state responses and a remarkable enhanced stability for tracking the desired path to different designated waypoints.

Design Process of the avionics subsystem of Colibrí mission: An experience report.

Abstract Universidad Panamericana students are working in the design and build process of a nanosatellite, specifically a CubeSat, a common trend for the aerospace industry that started rising in the last decade. While many of the common problems of an aerospace mission are solved or diminished considerably by the CubeSat standards, there is still a lot of development required to reach each of the objectives of a particular mission, especially those focused on scientific research. Regarding the avionics subsystem, custom development is needed to allow for the integration of the payload subsystem, which is mission specific, as well as general-purpose Commercial Off The Shelf components. Providing a reliable, robust and efficient integration represents the biggest challenge for the design of the avionics subsystem. In this paper the avionics team presents experiences and challenges that they have faced and how they lead to the development of a completely new component, a Printed Circuit Board with a Field-Programmable Gate Array controlling, reading and sampling the fast and heavy data provided by the payload sensors in order to lighten, adequate and deliver the information to and for the satellite On Board Computer. Additionally, the interconnection between all electronic components of the satellite, at physical level (wiring design, environmental and electromagnetic compatibility), as well as the logical compatibility and feasibility of the components that will be exchanging commands and data through different communication protocols. Finally, this paper presents how Colibri Mission has an academic impact since it had to solve those challenges without the experience that most CubeSat missions have, and how the spread of that knowledge opens the CubeSat industry to a country that previously was not able to participate on it.

СТРУКТУРА И ИЕРАРХИИ ИНФОКОММУНИКАЦИОННЫХ СИСТЕМ В СИСТЕМАХ ПОМОЩИ ВОДИТЕЛЮ КАК ШАБЛОНЫ ПРОЕКТИРОВАНИЯ ПОДСИСТЕМ БЕСПИЛОТНЫХ ТРАНСПОРТНЫХ СРЕДСТВ

The article presents the structure of infocommunication systems of unmanned transport systems developed by the author, which combines the main information subsystems of the control loop in Advanced driver-assistance systems (ADAS) and shows their interaction. The analysis of the architecture of the ADAS system as a complex system from the point of view of the application of Mesarovich's theory of hierarchical multilevel systems is given (also known as stratification process) - as a result of which ADAS infocommunication systems are presented in the form of a hierarchy of the strata-layers-echelons type. Such a representation has scientific novelty as the application of stratification methods to the description of ADAS infocommunication systems and practical value in the design of the ADAS architecture and the creation of templates for the design of unmanned transport systems infocommunication subsystems.

Modeling and Compensation of Time-Delay Effects in HILS of Aerospace Systems

The flight subsystems of aerospace vehicle must be introduced in Hardware In Loop Simulation (HILS) testbed prior to actual field tests to evaluate their performance in real-time scenario. This helps greatly in the design and development of vehicle subsystems. The HILS results are suffering due to unwanted diverging oscillations, which limit the HILS testbed effectiveness in evaluating the actual performance of embedded systems of Aerospace vehicle. It is found that the oscillations are due to the time delay introduced in HILS testbed. In this paper different delay compensation methods were highlighted. The Non Real Time simulation (NRT) testbed was developed and modeling of the delay effect is done by simulating the diverging oscillations. A suitable compensation method is also implemented in NRT simulation. The same compensation method was implemented in actual real-time HILS also to see its effectiveness.

Design of Microwave Photonic Subsystems Using Brillouin Scattering

With the rapid development of microwave photonic functionalities to support 5G and defence systems, there has been an increased interest in employing stimulated Brillouin scattering (SBS)-based functionalities to perform tasks that are currently difficult to achieve with conventional electronic devices. Several advances have been made using on-chip SBS to demonstrate RF frequency phase shifters, bandpass and bandstop filters, measurement systems, and delay lines. In this article, we provide an overview of some of these developments made possible by strong on-chip SBS gain. We also provide the reader with design guidelines on the selection of the appropriate waveguide geometry, subsystem design, and analog photonic link configurations to aid them in the realisation of their requisite MWP subsystem. We also focus on some of the design trade-offs that need to be considered when using integrated SBS.

Performance Enhancement of a Sludge Continuous Feed Heat Pump Drying System by Air Deflectors and Auxiliary Cooling Subsystems

This study proposes an improved design for a typical sludge continuous feeding drying system connected with three air-source heat pumps. The system’s performance was further improved using air-deflectors on the drying chamber’s internal sidewalls, enhancing the heat and mass transfer between the conveyor sludge and circulating airflow. In this study, numerical analysis was performed to elucidate the deflector designs on the airflow field and thermal temperature field distributions in the drying chamber. The specific moisture extraction rate (SMER) value was quantified to evaluate the system’s overall improvement during experiments. With a suitable deflector design, the average percent water content in sludge could be further reduced to 22.2% with drying time of 18.3 h, and the SMER value could be enhanced from 1.38 kg/kWh to as high as 1.83 kg/kWh with an increment of 32.44%. Moreover, to prevent overloading and frequent shutdown of the compressors, an auxiliary cooling subsystem was designed to attain stable operational conditions. By the auxiliary cooling subsystem design, the compressors’ shutdown can be avoided, the temperature difference between airflow inlets and outlet of the drying chamber can be increased, and SMER value can be further increased to a value of 1.94 kg/kWh.