scholarly journals Mathematical model for determining the design parameters of an inflatable payload-bearing space platform

2021 ◽  
Vol 2021 (4) ◽  
pp. 66-78
Author(s):  
E.O. Lapkhanov ◽  
◽  
O.S. Palii ◽  
Keyword(s):  
Mathematical Model ◽  
Satellite System ◽  
Inertia Tensor ◽  
Parameter Analysis ◽  
Design Parameters ◽  
Space Technology ◽  
Wide Range ◽  
Distributed Satellite ◽  
The Mathematical Model ◽  
Space Platform

The development and application of inflatable space structures is of considerable interest in modern space science and technology. Today, these structures enjoy wide application from aerodynamic inflatable deorbit means to inflatable residential sections for the International Space Station. This is because the masses of inflatable structures are smaller in comparison with others, which in turn minimizes the cost of their orbital injection. In view of the considerable interest in orbital constellations, the authors of this article propose the use of an inflatable space aerodynamic system as a platform for a payload. In doing so, we obtain a distributed satellite system on an inflatable space platform. The advantage of this technology is that it assures the maintenance of the relative position of the elements (payload) of a distributed satellite system of this type with minimal energy consumption. In its turn, to analyze the features of the operation of a particular space technology, its mathematical model is required. Because if this, the aim of the article is to develop a mathematical model for estimating the design parameters of an inflatable payload-bearing space platform. The mathematical model of the operation of an inflatable payload-bearing space platform developed in this work consists of three modules: a module of orbital motion, a module of calculation of the thermodynamic parameters of the inflatable platform, and a module of calculation of its variable inertia tensor. The article also identifies four gas modes of operation of the inflatable segment of the space platform and gives the inertia tensor as a function of the ambient temperature, which is necessary for further research. It should be noted that the application of the mathematical model allows a priori analysis of a wide range of inflatable space platform design parameters. On this basis, a design parameter analysis method that uses this model was developed. The application of this method may greatly simplify further research into the synthesis of an angular motion controller for an inflatable payload-bearing space platform, the choice of the design parameters of inflatable segment shell materials, and the study of the platform operation in different gas modes.

Robust sideslip angle observer of commercial vehicles based on cornering stiffness estimation using neural network

2022 ◽  
pp. 095440702110724
Author(s):  
Chenyu Zhou ◽  
Liangyao Yu ◽  
Yong Li ◽  
Jian Song
Keyword(s):  
Neural Network ◽  
Mathematical Model ◽  
Stability Control ◽  
Estimation Accuracy ◽  
Accurate Estimation ◽  
Commercial Vehicles ◽  
Sideslip Angle ◽  
The Neural Network ◽  
Wide Range ◽  
The Mathematical Model

Accurate estimation of sideslip angle is essential for vehicle stability control. For commercial vehicles, the estimation of sideslip angle is challenging due to severe load transfer and tire nonlinearity. This paper presents a robust sideslip angle observer of commercial vehicles based on identification of tire cornering stiffness. Since tire cornering stiffness of commercial vehicles is greatly affected by tire force and road adhesion coefficient, it cannot be treated as a constant. To estimate the cornering stiffness in real time, the neural network model constructed by Levenberg-Marquardt backpropagation (LMBP) algorithm is employed. LMBP is a fast convergent supervised learning algorithm, which combines the steepest descent method and gauss-newton method, and is widely used in system parameter estimation. LMBP does not rely on the mathematical model of the actual system when building the neural network. Therefore, when the mathematical model is difficult to establish, LMBP can play a very good role. Considering the complexity of tire modeling, this study adopted LMBP algorithm to estimate tire cornering stiffness, which have simplified the tire model and improved the estimation accuracy. Combined with neural network, A time-varying Kalman filter (TVKF) is designed to observe the sideslip angle of commercial vehicles. To validate the feasibility of the proposed estimation algorithm, multiple driving maneuvers under different road surface friction have been carried out. The test results show that the proposed method has better accuracy than the existing algorithm, and it’s robust over a wide range of driving conditions.

Mobile Worm-Like Robots for Pipe Inspection

2015 ◽  
pp. 168-218 ◽  
Author(s):  
Sergey Fedorovich Jatsun ◽  
Andrei Vasilevich Malchikov
Keyword(s):  
Mathematical Model ◽  
Control System ◽  
Mobile Robots ◽  
Experimental Studies ◽  
Design Parameters ◽  
Robot Motion ◽  
Robot Dynamics ◽  
Confined Space ◽  
Pipe Inspection ◽  
The Mathematical Model

This chapter describes various designs of multilink mobile robots intended to move inside the confined space of pipelines. The mathematical model that describes robot dynamics and controlled motion, which allows simulating different regimes of robot motion and determining design parameters of the device and its control system, is presented. The chapter contains the results of numerical simulations for different types of worm-like mobile robots. The experimental studies of the in-pipe robots prototypes and their analyses are presented in this chapter.

scholarly journals Parametric Method For Evaluating Optimal Ship Deadweight

2014 ◽  
Vol 21 (2) ◽  
pp. 3-8
Author(s):  
Jan P. Michalski
Keyword(s):  
Mathematical Model ◽  
Closed Form ◽  
Parametric Method ◽  
Freight Rate ◽  
Ship Design ◽  
Design Parameters ◽  
Optimal Value ◽  
Simplifying Assumptions ◽  
The Mathematical Model ◽  
Economic Measure

Abstract The paper presents a method of choosing the optimal value of the cargo ships deadweight. The method may be useful at the stage of establishing the main owners requirements concerning the ship design parameters as well as for choosing a proper ship for a given transportation task. The deadweight is determined on the basis of a selected economic measure of the transport effectiveness of ship - the Required Freight Rate (RFR). The mathematical model of the problem is of a deterministic character and the simplifying assumptions are justified for ships operating in the liner trade. The assumptions are so selected that solution of the problem is obtained in analytical closed form. The presented method can be useful for application in the pre-investment ships designing parameters simulation or transportation task studies.

Engineering Constraint Management Based on an Occurrence Matrix Approach

1993 ◽  
Vol 115 (1) ◽  
pp. 103-109 ◽  
Author(s):  
R. Agrawal ◽  
G. L. Kinzel ◽  
R. Srinivasan ◽  
K. Ishii
Keyword(s):  
Mathematical Model ◽  
Degrees Of Freedom ◽  
Inequality Constraints ◽  
Design Parameters ◽  
Constraint Management ◽  
Management Concepts ◽  
Occurrence Matrix ◽  
Torsion Bar ◽  
The Mathematical Model ◽  
Management Algorithms

In many mechanical systems, the mathematical model can be characterized by m nonlinear equations in n unknowns. The m equations could be either equality constraints or active inequality constraints in a constrained optimization framework. In either case, the mathematical model consists of (n-m) degrees of freedom, and (n-m) unknowns must be specified before the system can be analyzed. In the past, designers have often fixed the set of (n-m) specification variables and computed the remaining n variables using the n equations. This paper presents constraint management algorithms that give the designer complete freedom in the choice of design specifications. An occurrence matrix is used to store relationships among design parameters and constraints, to identify dependencies among the variables, and to help prevent redundant specification. The interactive design of a torsion bar spring is used to illustrate constraint management concepts.

scholarly journals Kinetics of filtration consolidation of water-saturated clay soils

2020 ◽  
pp. 86-95 ◽  
Author(s):  
O. V. Ageikina ◽  
V. V. Vorontsov ◽  
R. R. Sufyanov
Keyword(s):  
Mathematical Model ◽  
Porous Medium ◽  
Saturated Porous Medium ◽  
Experimental Studies ◽  
Saturated Soils ◽  
Consolidation Process ◽  
Filtration Consolidation ◽  
Wide Range ◽  
Water Saturated ◽  
The Mathematical Model

The relevance of the research processes filtration consolidation due to the place of water-saturated soils in various design solutions related to the exploration, production and transportation of hydrocarbons. It should be noted that the diversity of soils led to the emergence of a wide range of mathematical models, obtained on the basis of generalization of experimental data and various assumptions to simplify engineering calculations. The article presents the results of theoretical and experimental studies of the mathematical model of the consolidation process of a water-saturated porous medium. This model is based on simplifying assumptions that are different from those adopted in well-known solutions. A fundamental approach to the formation of the model was developed on the basis of the kinetic representations of chemical reactions used in solving the environmental problems of epoxidation reactions of olefins. We determined the parameters of the mathematical model of the consolidation process of the saturated porous medium of clayey soil and confirmed its adequacy by the research results. In addition, we established the parameters of the field of non-equilibrium filtration, reducing the nonexistent ability of water-saturated soils.

scholarly journals Development and Application of a Thermal Comfort Model in Buildings

2022 ◽  
Vol 7 ◽  
pp. 1
Author(s):  
Andrés Vilaboa Díaz ◽  
Pastora M. Bello Bugallo
Keyword(s):  
Mathematical Model ◽  
Thermal Comfort ◽  
Thermal Inertia ◽  
Design Parameters ◽  
System Response ◽  
Thermal Mass ◽  
The European Union ◽  
External Temperature ◽  
Temperature Variations ◽  
The Mathematical Model

Buildings are one of the systems that more energy consumed in the European Union. The study of the thermal envelope is interesting in order to reduce the energy losses. For that, a mathematical model able to predict the system response to external temperature variations is developed. With the mathematical model, different thermal envelope elements of a building based on the lag and the cushioning of the resultant wave can be characterized. In addition, it is important to analyse where the insulation is placed, because when the insulation is outside and the thermal mass is inside, the system produces a response with smooth temperature variations than when the insulation is inside. Therefore, placing the outside insulation generates more steady indoor temperatures, increasing the thermal comfort inside the building. To complete the mathematical model that allows predicting the temperature inside a building taking into account the solar inputs and the thermal inertia of the building. This study will help to establish the optimum design parameters in order to build sustainable and comfortable buildings. Furthermore, it will take one step forward in the construction of nearly Zero-Energy Buildings.

scholarly journals MATHEMATICAL AND PHYSICAL BASIS FOR DEVELOPING A SIMULATOR FOR TOWING AND PULLING OF WHEELED AND TRACKED MACHINES

2021 ◽  
Vol 5 (4) ◽  
pp. 135-139
Author(s):  
Alexander Serhieiev ◽  
Andriy Krivoshapka ◽  
Oleksandr Isakov ◽  
Vyacheslav Lysenko ◽  
Viktor Moskalenko ◽  
...  
Keyword(s):  
Mathematical Model ◽  
Physical Basis ◽  
Design Parameters ◽  
System Of Equations ◽  
Aramid Fibers ◽  
Tracked Vehicles ◽  
General Scientific ◽  
And Performance ◽  
The Mathematical Model ◽  
Physical Quantities

The subject matter of the article is the towing and pulling of wheeled and tracked vehicles with the use of cable ropes and dynamic slings. The goal of the study is to determine the mathematical and physical basis for the development of a simulator for towing and pulling wheeled and tracked vehicles for researching to study the possibility of using aramid fibers of cable-ropes and dynamic slings. The tasks to be solved are: based on the analysis of the main roads and ground characteristics to formalize the list of calculated parameters and physical quantities determine the amount of evacuation work when pulling, towing and transporting wheeled and tracked vehicles; to develop a mathematical model that describes the process of pulling and towing wheeled and tracked vehicles using cable ropes and dynamic slings. General scientific and special methods of scientific knowledge are used. The following results are obtained. By analyzing the main characteristics of roads and ground, a formalized list of design parameters and physical quantities that determine the volume of evacuation work during the towing and pulling of wheeled and tracked vehicles was obtained. Mathematical model, describes the process of pulling and towing wheeled and tracked machines using cable ropes and dynamic slings have been  compiled as a system of equations with different order. analyzed existing technology for the production of aramid fibers, their strengths and weaknesses, and formed a research polygon with regard to the peculiarities of the operation of wheeled and tracked vehicles. Existing technology for the production of aramid fibers, their strengths and weaknesses, and formed a research polygon with regard to the peculiarities of the operation of wheeled and tracked vehicles have been analyzed. Conclusions. The main roads and ground characteristics  that determine the vehicles. evacuation conditions are the following: the type of road or ground, their possibility depending on the season and precipitation, the presence of ascents and descents, as well as the nature of road (ground) interaction with caterpillars determined by resistance coefficients. movement and traction. The mathematical model of pulling a wheeled and tracked vehicle using cable ropes and dynamic can be presented as a system of equations: the jerk carried out by the machine in time reflected third-order differential equation, assuming that all the energy accumulated by the cable is numerically equal to the work of moving stuck machine, corresponds to the equality of the corresponding integrals; the properties of aramid fibers that affect the strength and performance characteristics of cable ropes can be formally expressed through the elongation of the cable. Analysis of strength and service properties of aramid fibers opens the way to improvement of manufacturing technology of cable ropes and dynamic slings for pulling and towing of wheeled and tracked vehicles.

Research of Riveting Structure Identification and Characteristic Parameter Analysis Based on SVM

2014 ◽  
Vol 1049-1050 ◽  
pp. 1554-1557
Author(s):  
Jian Feng Yang ◽  
Gang Jiang ◽  
Jian Fei Chen
Keyword(s):  
Mathematical Model ◽  
Image Processing ◽  
Research Result ◽  
Characteristic Parameter ◽  
Parameter Analysis ◽  
Structure Identification ◽  
Support Vector ◽  
Vector Machines ◽  
Set Up ◽  
The Mathematical Model

In order to help department to make a decision whether the equipment need maintenance, some people trained the sample of characteristic parameter for riveting structure, and set up the model to recognize target by computer vision. However, we are difficult to find the research result about the affiliation between the characteristic parameter of the riveting structure and the model. In this paper, we make the image processing first, and use SVM (Support Vector Machines) algorithm to train the sample of characteristic parameter for rivet head. Finally, we research the affiliation between the characteristic parameter for the rivet head and the mathematical model, and test the accuracy of the model.

Design and Modeling of an Experimental ROV with Six Degrees of Freedom

Drones ◽  
2021 ◽  
Vol 5 (4) ◽  
pp. 113
Author(s):  
Aleksey Kabanov ◽  
Vadim Kramar ◽  
Igor Ermakov
Keyword(s):  
Mathematical Model ◽  
Degrees Of Freedom ◽  
Experimental Tests ◽  
Underwater Vehicles ◽  
Six Degrees Of Freedom ◽  
Functional Capabilities ◽  
Classical Design ◽  
Wide Range ◽  
Reduced Costs ◽  
The Mathematical Model

With the development of underwater technology, it is important to develop a wide range of autonomous and remotely operated underwater vehicles for various tasks. Depending on the problem that needs to be solved, vehicles will have different designs and dimensions, while the issues surrounding reduced costs and increasing the functionality of vehicles are relevant. This article discusses the development of inspection class experimental remotely operated vehicles (ROVs) for performing coastal underwater inspection operations, with a smaller number of thrusters, but having the same functional capabilities in terms of controllability (as vehicles with traditionally-shaped layouts). The proposed design provides controllability of the vehicle in six degrees of freedom, using six thrusters. In classical design vehicles, such controllability is usually achieved using eight thrusters. The proposed design of the ROV is described; the mathematical model, the results of modeling, and experimental tests of the developed ROVs are shown.

Mathematical modeling of articulated passenger train spatial vibrations

2021 ◽  
Vol 2021 (2) ◽  
pp. 91-99
Author(s):  
O. Markova ◽  
◽  
H. Kovtun ◽  
V. Maliy ◽  
◽  
...  
Keyword(s):  
Mathematical Model ◽  
Differential Equations ◽  
Dynamic Characteristics ◽  
High Speed ◽  
Ride Quality ◽  
Railway Transport ◽  
Passenger Train ◽  
Wide Range ◽  
Random Track Irregularities ◽  
The Mathematical Model

The problem of high-speed railway transport development is important for Ukraine. In many countries articulated trains are used for this purpose. As the connections between cars in such a train differ from each other, to investigate its dynamic characteristics not a separate car, but a full train vibrations model is necessary. The article is devoted to the development of the mathematical model for articulated passenger train spatial vibrations. The considered train consists of 7 cars: one motor-car, one transitional car, three articulated cars, one more transitional car and again one motor-car. Differential equations of the train motion along the track of arbitrary shape are set in the form of Lagrange’s equations of the second kind. All the necessary design features of the vehicles are taken into account. Articulated cars have common bogies with adjoining cars and a transfer car and the cars are united by the hinge. The operation of the central hinge between two cars is modeled using springs and dampers acting in the horizontal and vertical directions. Four dampers between two adjacent car-bodies act as dampers for pitching and hunting and are represented in the model by viscous damping. The system of 257 differential equations of the second order is set, which describes the articulated train motion along straight, curved, and transitional track segments with taking into account random track irregularities. On the basis of the obtained mathematical model the algorithm and computational software has been developed to simulate a wide range of cases including all possible combinations of parameters for the train elements and track technical state. The study of the train self-exited vibrations has shown the stable motion in all the range of the considered speeds (40 km/h – 180 km/h). The results obtained at the train motion along the track maintained for the speedy motion have shown that all the dynamic characteristics and ride quality index insure train safe motion and comfortable conditions for the travelling passengers.

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