Introduction of additional inertial couplings in mathematical models of problems of vibration protection and vibration isolation

Для создания виброакустической защиты судового оборудования необходимо учитывать потоки колебательной энергии, распространяющиеся от источников как через опорные и неопорные связи, так и в виде воздушного шума. В работе представлены математические модели оценки эффективности амортизирующих креплений виброактивных механизмов морских объектов по колебательной мощности, учитываемые при обучении разрабатываемой нейросетевой системы классификации морских целей. Теоретические разработки в области виброзащиты и виброизоляции во многом имеют междисциплинарный характер и опираются на методы теории механизмов и машин, теоретической механики, теории колебаний, теории управления, используются методы инфорьт мационные технологии для оценки, поиска и выбора рациональных проектно-конструкторских решений. Создание амортизирующих устройств, способных защитить объекты от вибраций и ударов и, вместе с тем, обладающих ограниченными размерами, является сложной технической проблемой. В связи с этим первостепенное значение приобретают вопросы теории и расчета адаптивных виброзащитных систем. To create vibro-acoustic protection of ship equipment, it is necessary to take into account the flows of vibrational energy propagating from sources both through support and non-support connections, and in the form of air noise. The paper presents mathematical models for evaluating the effectiveness of shock-absorbing fasteners of vibro-active mechanisms of marine objects by vibrational power, which are taken into account when training the developed neural network system for classifying marine targets. Theoretical developments in the field of vibration protection and vibration isolation are largely interdisciplinary in nature and are based on the methods of the theory of mechanisms and machines, theoretical mechanics, vibration theory, control theory, information technology methods are used to evaluate, search and select rational design solutions. The creation of shock-absorbing devices that can protect objects from vibrations and shocks and, at the same time, have limited dimensions is a complex technical problem. In this regard, the issues of the theory and calculation of adaptive vibration protection systems are of paramount importance.

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Method of experimental evaluation of the efficiency coefficient of vibration protection of the rope-rod coupling "MAMSAR+A" of the diesel generator set DGA-8.83

MORSKIE INTELLEKTUAL`NYE TEHNOLOGII ◽

10.37220/mit.2021.52.2.038 ◽

2021 ◽

pp. 88-95

Author(s):

М.А. Минасян ◽

А.М. Минасян ◽

Ц. Цзэн

Keyword(s):

Experimental Evaluation ◽

Vibration Isolation ◽

Experimental Studies ◽

Original Method ◽

Efficiency Coefficient ◽

Diesel Generator ◽

Vibration Protection ◽

Rigid Connection ◽

Two Stages

Объектом исследования является опытный образец запатентованной канатностержневой муфты (КСМ) «MAMSAR+А» в качестве привода дизель-генераторного агрегата ДГА-8,83 мощностью 9,56 кВт при частоте вращения 1500 мин-1 с дизелем 2Ч 8,5/11 и генератором «ГК-5,6». Целью исследования является экспериментальная оценка коэффициента эффективности вибрационной защиты КСМ. Поставленная цель достигается разработкой и реализацией оригинальной методики экспериментальной оценки коэффициента эффективности КСМ с анализом и выводами результатов экспериментальных исследований. Экспериментальные исследования проводятся в два этапа. Первый этап – с упругим соединением КСМ, второй этап – с жестким соединением. Оригинальность методики экспериментальной оценки коэффициента эффективности вибрационной защиты КСМ главным образом заключается в том, что между двумя этапами экспериментальных исследований КСМ не демонтируется. Следовательно, качество центровки не нарушается. Усредненный коэффициент эффективности виброизоляции КСМ составляет от 3 до 8 дБ. The object of this research is a prototype of the patented wire rope coupling (KSM) "MAMSAR+A" as a drive for a diesel-generator unit DGA-8.83 with a power of 9.56 kW at a speed of 1500 min-1 with a 2CH 8.5/11 diesel engine and a generator "KG-5.6". The aim of the research is to experimentally evaluate the efficiency coefficient of vibration protection of the KSM. This goal is achieved by developing and implementing an original method for experimental evaluation the efficiency coefficient of the KSM with analysis and conclusions of the results of experimental studies. Experimental studies are conducted in two stages. The first stage - with an elastic connection of the coupling, the second stage - with a rigid connection. The originality of the method of experimental evaluation of the efficiency coefficient of vibration protection of the KSM mainly lies in the fact that the KSM is not dismantled between the two stages of experimental research. Therefore, the quality of alignment is not violated. The average coefficient of vibration isolation efficiency of the KSM is from 3 to 8 dB.

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Vibration Protection of Sensitive Components of Infrared Equipment in Harsh Environments

Shock and Vibration ◽

10.1155/2001/501572 ◽

2001 ◽

Vol 8 (1) ◽

pp. 55-69 ◽

Cited By ~ 9

Author(s):

A.M. Veprik ◽

V.I. Babitsky ◽

N. Pundak ◽

S.V. Riabzev

Keyword(s):

Vibration Isolation ◽

Harsh Environments ◽

Line Of Sight ◽

Infrared Sensor ◽

Isolation System ◽

Vibration Isolation System ◽

Vibration Isolators ◽

Vibration Protection ◽

Electro Optic ◽

Environmental Vibration

This article addresses the principles of optimal vibration protection of the internal sensitive components of infrared equipment from harsh environmental vibration. The authors have developed an approach to the design of external vibration isolators with properties to minimise the vibration-induced line-of-sight jitter which is caused by the relative deflection of the infrared sensor and the optic system, subject to strict constraints on the allowable sway space of the entire electro-optic package. In this approach, the package itself is used as the first-level vibration isolation stage relative to the internal highly responsive components.It was predicted analytically, and confirmed experimentally, that the proposed vibration isolation system would be capable of a sixfold reduction of the dynamic response of the infrared sensor as compared to the case of rigid mounting of the entire package.

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Application of the parallelogram mechanism with the effect of quasi-zero stiffness in the vibration protection systems of the operator’s chair of a road construction machine

Nauchno-tekhnicheskiy vestnik Bryanskogo gosudarstvennogo universiteta ◽

10.22281/2413-9920-2021-07-02-132-140 ◽

2021 ◽

Vol 7 (2) ◽

pp. 132-140

Author(s):

M.S. Korytov ◽

◽

V.S. Sherbakov ◽

I.E. Pochekueva ◽

◽

...

Keyword(s):

Vibration Isolation ◽

Tensile Force ◽

Road Construction ◽

Negative Stiffness ◽

Force Characteristic ◽

Straight Line Passing ◽

Tension Spring ◽

Vibration Protection ◽

Protection Systems ◽

Isolation Systems

For vibration protection of operators of construction and road machines, a promising direction is the use of passive vibration protection systems based on mechanisms with quasi-zero rigidity. Passive vibration isolation systems, being less complex than active ones, require less frequent maintenance, are cheaper to manufacture and more reliable than active ones. The problem of selecting the optimal, most reliable and simple design of the mechanism with the effect of quasi-zero rigidity remains urgent. In this case, the most widespread use of elements that create negative stiffness. This requires elements with positive stiffness in the mechanism, which complicates the design. More promising structures of mechanisms, where elements with negative stiffness are not separated into a separate structure. In mechanisms such as the parallelogram, studied in this work, a section with quasi-zero stiffness can be provided with just one tension spring, which simplifies the design and reduces the cost of the entire vibration protection system. By the method of direct analytical inference for the presented diagram of a parallelogram mechanism with one spring, analytical expressions are obtained for the tensile force of the spring necessary to compensate for the force of gravity of the chair with the operator on the height of the chair and the length of the spring. As an example, the graphical dependences of the spring tensile force on the chair lift and on the spring’s own length are given as an example. It was found that the static force characteristic of the spring is a straight line passing through the origin. That is, the zero force corresponds to the zero spring length, which is not technically feasible. It is proposed to use a mechanism that replaces the tension spring, which will provide a given power characteristic.

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Synthesis of snubber's spectral characteristics for vibration protection of sensitive components in airborne gyrostabilized electro-optic payloads

Proceedings of the Institution of Mechanical Engineers Part C Journal of Mechanical Engineering Science ◽

10.1243/09544062jmes980 ◽

2008 ◽

Vol 222 (10) ◽

pp. 1885-1897 ◽

Cited By ~ 4

Author(s):

A Veprik ◽

S Djerassy ◽

V Babitsky

Keyword(s):

Environmental Conditions ◽

Vibration Isolation ◽

Spectral Characteristics ◽

Low Frequency ◽

Primary Objective ◽

Vibration Protection ◽

Low Frequency Vibration ◽

Electro Optic ◽

Critical Components ◽

Optimal Approach

Low-frequency vibration isolation of airborne gyrostabilized electro-optic payloads is the ultimate and proven solution aimed at improving their imagery performance, primarily during a quiet cruise flight. This portion of the airborne mission is characterized by rather moderate environmental conditions, under which vibration mounts operate in a linear working range within the predefined working rattle space, which eventually results in better performances. Compliant snubbers are indispensable emergency components in such vibration protection arrangements primarily needed during exposure to the extreme environmental conditions typical of the relatively short periods of airborne missions such as take-off, landing, weapon application, etc. Their primary objective is to protect these soft vibration mounts and prevent their bottoming and disintegration without any impulsive accelerations that compromise the integrity of the payload frame and fragile internal components mounted upon it. The optimal approach for designing a snubbed vibration isolator, delivering a fail-safe environment for both the payload frame and critical components subjected to tight constraints imposed on the size, weight, and price does not seem to exist. It is intended to devise the optimal design approach and to demonstrate its application on low-frequency vibration mounted electro-optic payload comprising the vibration sensitive integrated dewar-detector-cooler assembly.

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Protection of precision spacecraft equipment from internal sources of vibration

Spacecrafts & Technologies ◽

10.26732/j.st.2021.4.05 ◽

2021 ◽

Vol 5 (4) ◽

pp. 217-226

Author(s):

Yu. A. Zhukov ◽

E. B. Korotkov ◽

S. A. Matveev ◽

N. S. Slobodzyan ◽

O. V. Shirobokov

Keyword(s):

Vibration Isolation ◽

Vibration Suppression ◽

Thermal Control ◽

Vibration Source ◽

Electric Pump ◽

Pump Unit ◽

Isolation System ◽

Vibration Isolators ◽

Vibration Protection ◽

Vibration Dampers

The work is devoted to the protection of a spacecraft from the influence of unacceptable internal vibration sources. The urgency of reducing the vibration activity on board the spacecraft to improve the accuracy of the target equipment is indicated. A particular problem of vibration protection of the spacecraft platform from a vibration source – an electric pump unit of a liquid thermal control system – is being solved. The basic requirements for electric pump unit vibration protection have been determined. Possible ways to reduce the level of vibration excited by the electric pump unit on the surface of the spacecraft fixation are considered. Particular attention is paid to such vibration protection methods as damping and vibration isolation, implemented by installing special vibration protection devices between the source (electric pump unit) and the object (spacecraft) – vibration isolators and vibration dampers. The principles of operation of vibration dampers and vibration isolators, the most common materials for vibration dampers are described. Examples of constructive solutions for linear single-axial vibration isolators are considered, recommendations for the use of promising products are developed. Particularemphasis is placed on the use of metal rubber as a material for vibration isolators. With regard to a specific design of electric pump unit, a diagram of the spatial structure of vibration isolation is proposed. Formulas for calculation are given in detail, a mathematical model of the vibration isolation system is developed. The procedure for calculating the parameters of the system has been formed. Based on the model, the maximum possible level of vibration suppression in the mid-frequency region was determined. Minimum required number of operable pixels was identified for monitoring the water surface with sufficient accuracy and reliability.

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Indirect Control of Oscillations: Elements of Theory

SPIIRAS Proceedings ◽

10.15622/sp.18.1.148-175 ◽

2018 ◽

Vol 18 (1) ◽

pp. 148-175

Author(s):

Vladimir Chernyshev ◽

Leonid Savin ◽

Olga Fominova

Keyword(s):

Vibration Isolation ◽

Dynamic Properties ◽

Harmonic Balance Method ◽

Frequency Region ◽

Optimal Sequence ◽

Isolation System ◽

Vibration Isolation System ◽

Basic Model ◽

Indirect Control ◽

Vibration Protection

A brief review of the main research areas in the field of controlled vibration protection systems is given. It is shown that Vibration systems with indirect control processes of oscillations allow with a minimum expenditure of energy to ensure programmable switching parameters and structures, in which the dissipative restoring and inertial forces generated on the basis of active impact. Within synthesis of indirect control the chains of new auxiliary mathematical constructs for finding optimal synthesizing functions of the elastic-damping units parameters control are obtained. It enabled to separate a base model with intermittent damping and base model with impulse trap. As a result of the study, based on the harmonic balance method, the dynamic properties of the basic model with intermittent damping, calculation formulas are obtained for determining the parameters of the compensation effect and calculating the dynamic coefficient. It is established that, with an optimal sequence of damping switching, the resonant phenomena are eliminated, and the transient processes decay within one period of the kinematic perturbation. The basic model with a pulse trap imitates the limiting variant of intermittent damping and realizes the process of superimposing constraining bonds, the sequence and duration of which are new variables essentially increasing controllability. And for indirect pulse control, there exicts a certain minimum of power consumption independent of the achieved effect of vibration protection. A regulated increase in the duration of the application of the restraining coupling in the low-frequency region and a decrease in this duration in the high-frequency region provides a monotonically decreasing dependence on the dynamic coefficients over the entire frequency range. An example of a solution to the optimization problem of controlling the damping process for a basic model of a vibration isolation system is considered. It is established that intermittent damping is an indispensable feature of the optimality of the vibration isolation system: the damper switches on when the sign of the object's speed has changed and turns off when the object's displacement sign has changed.

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Bench for the study of static and dynamic indicators of vibration isolators

10.36652//0042-4633-2020-4-36-40 ◽

2020 ◽

pp. 36-40

Author(s):

P.V. Sirotin ◽

I.YU. Lebedinskiy ◽

M.M. Jileykin ◽

M.I. Syisoev

Keyword(s):

Vibration Isolation ◽

Test Bench ◽

Operating Conditions ◽

Technological Equipment ◽

Vibration Isolator ◽

Vibration Isolators ◽

Vibration Protection ◽

Dynamic Indicators

A test bench is developed to evaluate the properties of vibration mounts intended for vibration isolation of units, assemblies and workplaces of vehicle operators and technological equipment. The estimation of static and dynamic indicators of vibration isolators under loading close to operating conditions is presented. Keywords vibration isolator, vibration protection, vibration mount stiffness, damping, bench. [email protected]

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Discrete-continual mathematical models in solving vibration protection problems of building structures

MATEC Web of Conferences ◽

10.1051/matecconf/201821206003 ◽

2018 ◽

Vol 212 ◽

pp. 06003 ◽

Cited By ~ 1

Author(s):

Vladimir Sobolev

Keyword(s):

Mathematical Models ◽

Vibration Frequency ◽

Dynamic Interaction ◽

Technological Equipment ◽

Building Structures ◽

Load Bearing ◽

Industrial Structures ◽

Vibration Protection ◽

Protection Systems

The paper outlines the method of forming mathematical models for the dynamic interaction of the vibroactive technological equipment with load-bearing structures of industrial structures on the basis of discrete-continual approximations previously developed by the author. Ways of implementing methods in the formation of vibration protection systems of structures are provided in the paper. The features of systems’ functioning and their sensitivity to fluctuating vibration frequency processes are also described.

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Simulation model of a chair vibration protective mechanism with a part of quasi-zero-stiffness for the operator of a road-building machine

Nauchno-tekhnicheskiy vestnik Bryanskogo gosudarstvennogo universiteta ◽

10.22281/2413-9920-2020-06-04-486-496 ◽

2020 ◽

Vol 6 (4) ◽

pp. 486-496

Author(s):

M.S. Korytov ◽

◽

V.S. Sherbakov ◽

I.E. Pochekueva ◽

◽

...

Keyword(s):

Mathematical Model ◽

Vibration Isolation ◽

Degree Of Freedom ◽

Protection System ◽

Production Factor ◽

Protective Mechanism ◽

Static Force ◽

Vertical Movements ◽

Vibration Protection ◽

Protection Systems

Vibrations of construction and road machinery components that occur during their operation are a harmful production factor for machine operators, therefore, their reduction can be considered a very urgent task. The main route of vibration transmission is through vibration isolation systems for the operator’s seat and cab. The easiest and most cost-effective way to isolate the operator from vibration is through his seat by reducing vibration. The simplest and most reliable vibration protection systems with one degree of freedom limited by vertical movements of the chair can be used for the chairs. Vibration protection mechanisms and systems with quasi-zero rigidity are considered promising. They provide constant static force over a certain range of movement of the object. The task of developing mathematical models describing vibration protection systems with quasi-zero rigidity is urgent. In the Matlab software package using the Simscape library for modeling physical elements, a simulation mathematical model of the vibration protection system of a chair with one degree of freedom has been developed. The base of the chair in the developed model performs harmonic sinusoidal movements. The output parameters of the developed mathematical model are the time dependences of the chair coordinates and accelerations. The blocks used in the model are described, the static force characteristics are given, given using the Hermite spline. The model includes a block of hard movement restrictions. An example of using the developed simulation mathematical model of the chair is given. The developed model makes it possible to specify both the dimensions of the quasi-zero stiffness section and the shape of the curves of the force static characteristics of the vibration protection system. It can be integrated into higher level models.

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