scholarly journals Design of impact dampers for transporting cargoes by two-link vehicles

2021 ◽  
Vol 2 (7 (110)) ◽  
pp. 85-94
Author(s):  
Ihor Vikovych ◽  
Ljubomyr Krainyk ◽  
Roman Zinko ◽  
Vitalij Popovych ◽  
Orest Horbai
Keyword(s):  
Rational Design ◽  
The Body ◽  
Design Parameters ◽  
Viscoelastic Damping ◽  
Impact Loads ◽  
Vibration Protection ◽  
Rational Design Parameters ◽  
Transition Modes ◽  
Impact Phenomena ◽  
The Impact

This paper considers the influence of the transitional modes of movement (acceleration, braking) of a multi-link vehicle on the vibration protection of transported non-fixed or partially fixed cargoes. The impact phenomenon, in this case, can be strengthened by the existence of coupling mechanisms between the links of a multi-link vehicle. To reduce such horizontal impact loads, it is advisable to use elements with viscoelastic damping in the coupling devices of a multi-link vehicle. To study the actual impact phenomena during the transportation of non-fixed or partially fixed cargoes under the extreme modes of movement of two-link vehicles, it is proposed to use a flat two- and three-mass dynamic model with viscoelastic damping. At the same time, the theory of elastic impact has been applied while the elastic-damping characteristics of vehicles' suspensions were not taken into consideration. It has been shown that the reported research results make it possible to estimate the approximate values of the mechanical parameters for restrictive devices that protect non-fixed or partially fixed cargoes from impact, during the transition modes of transportation, depending on the conditions of motion. This practically makes it possible to select the rational design parameters for the elements of viscoelastic restrictive devices, in particular elastic elements and dampers, in order to reduce impact loads on non-fixed heavy cargoes during transportation under extreme modes of movement. Based on this study, a procedure of vibration protection of non-fixed or partially fixed cargoes in the body of a two-link vehicle during its uneven movement has been proposed, which implies determining the maximum dynamic loads on these cargoes as well as the possibility of choosing the rational design parameters for restrictive devices in order to prevent or reduce the impact of these cargoes hitting the restrictive devices

scholarly journals ON THE ISSUE OF DETERMINING THE CRITICAL CUTTING SPEED OF THE MECHANISM FOR FORMING AND TRIMMING THE FALSE EDGE OF THE DORNIER RAPIER LOOM

2021 ◽  
Vol 53 (3) ◽  
pp. 37-40
Author(s):  
Svitlana V. Bukina ◽  
Tatiana A. Sitnikova
Keyword(s):  
Rational Design ◽  
Mutual Influence ◽  
Cutting Speed ◽  
Design Parameters ◽  
Working Process ◽  
Forming Mechanism ◽  
Rational Design Parameters ◽  
Calculation Results ◽  
Knife Blade ◽  
The Impact

In this paper, an attempt is made to develop a method for determining the critical cutting speed of the threads of the false edge of the edge-forming mechanism of the weaving rapier machine. The proposed calculation method takes into account the impact nature of the cutting process at a critical speed, which allows taking into account the mutual influence of the parameters of the working process and more fully assess the mechanics of this process, in which the intensity of the cutting force and the value of the contact stress take the maximum value. The paper calculates the critical cutting speed for some of the main types of threads used and the parameters of the knife blade. The presented calculation results can be used to select rational design parameters of the knife blade, depending on the type of processed threads, when designing and researching new edge-forming mechanisms on looms.

scholarly journals MOVEMENT STABILITY OF A SECTION OF THE MACHINE FOR BLACK FALLOW CULTIVATION IN A LONGITUDINAL-VERTICAL PLANE

2020 ◽  
Author(s):  
Volodymyr Bulgakov ◽  
Semjons Ivanovs ◽  
Volodymyr Nadykto ◽  
V. Kaminsky ◽  
L. Shymko ◽  
...  
Keyword(s):  
Mathematical Model ◽  
Rational Design ◽  
Vertical Plane ◽  
Design Parameters ◽  
Field Investigations ◽  
Special Machine ◽  
Rational Design Parameters ◽  
Movement Stability ◽  
The Impact ◽  
Angle Of Rotation

One of the tasks of using the black fallow in agricultural production is the weed control and the moisture conservation in the soil. Application of the most advanced soil cultivation technologies ensures preservation of no more than 75% of precipitations in the soil. To improve the state of this issue, we have developed a special machine for processing the black fallow. A mathematical model has been developed that describes the dynamics of the movement of the harrow section in a longitudinal-vertical plane, and its solution is given, which allows investigation of the impact of this or that design parameter upon the dynamics of the angle of rotation in time. The adequacy of the developed mathematical model is confirmed by special laboratory and field investigations of the created experimental machine. With rational design parameters the rotation angle of the harrow section in a longitudinal-vertical plane will not exceed – 3º, and the time of its exit to the equilibrium position will not exceed 16...17 s.

Making Up 3D Bodies

2021 ◽  
Vol 4 (2) ◽  
pp. 1-9
Author(s):  
Kiona Hagen Niehaus ◽  
Rebecca Fiebrink
Keyword(s):  
Software Tool ◽  
The Body ◽  
Design Parameters ◽  
Artistic Practice ◽  
Human Form ◽  
Modeling Systems ◽  
Exploratory Approach ◽  
Disability Status ◽  
High Level ◽  
The Impact

This paper describes the process of developing a software tool for digital artistic exploration of 3D human figures. Previously available software for modeling mesh-based 3D human figures restricts user output based on normative assumptions about the form that a body might take, particularly in terms of gender, race, and disability status, which are reinforced by ubiquitous use of range-limited sliders mapped to singular high-level design parameters. CreatorCustom, the software prototype created during this research, is designed to foreground an exploratory approach to modeling 3D human bodies, treating the digital body as a sculptural landscape rather than a presupposed form for rote technical representation. Building on prior research into serendipity in Human-Computer Interaction and 3D modeling systems for users at various levels of proficiency, among other areas, this research comprises two qualitative studies and investigation of the impact on the first author's artistic practice. Study 1 uses interviews and practice sessions to explore the practices of six queer artists working with the body and the language, materials, and actions they use in their practice; these then informed the design of the software tool. Study 2 investigates the usability, creativity support, and bodily implications of the software when used by thirteen artists in a workshop. These studies reveal the importance of exploration and unexpectedness in artistic practice, and a desire for experimental digital approaches to the human form.

scholarly journals TO THE DEVELOPMENT OF SOIL TILLAGE WORKING UNITS ON THE BASIS OF FIELDS SOLIDGRAMS

2018 ◽  
Vol 13 (2) ◽  
pp. 100-106 ◽  
Author(s):  
Юрий Казаков ◽  
Yuriy Kazakov ◽  
Владимир Медведев ◽  
Vladimir Medvedev ◽  
Алексей Терентьев ◽  
...  
Keyword(s):  
Degrees Of Freedom ◽  
Rational Design ◽  
Soil Tillage ◽  
Design Parameters ◽  
Factors Affecting ◽  
Rational Design Parameters ◽  
Automatic Adaptation ◽  
Cultivation Technology ◽  
Elastic Characteristics

When solving engineering problems in soil cultivation, soil resistivity is applied. The use of solidograms is more preferable in the construction of soil-working tools and the operation of agricultural machinery. The developed technologies and instruments for continuous layerwise determination of the longitudinal hardness of the arable layer make it possible to obtain soil maps by hardness, to create a database. Factors affecting hardness variability include crop cultivation technology, row spacing, parameters, number and gauge of movers of mobile power tools and agricultural tools, the width of the technological track. The influence of the degrees of freedom of the working units on the intensity of loosening of the soil, the magnitude and nature of the change in the traction resistance, both as a separate working unit and the entire implement, is considered. A combined working unit consisting of a cutaway knife, a built-in drainer, a spring bender on a spring-loaded draft, which creates conditions for the realization of low-intensity types of deformation, the Baushinger effect is proposed. The advantage of the working unit is the continuous automatic adaptation of geometric parameters. For design and strength calculation of such working units, synthesis of elastic characteristics, it is recommended to use methods of the theory of random oscillations. The force and kinematic perturbation of the oscillations is caused by the variability of the hardness of the arable layer, the speed of movement of the working organ, the vibrorheological properties of the soil, and the parameters of the elastic characteristics of the system of springs. The rationale for the smoothing capability of the dynamical system being designed is substantiated by justifying rational design parameters, selecting the material, determining the system parameters by known characteristics at the input and output.

scholarly journals Multi-section coupling device for aggregation of modern seeding machines

2021 ◽  
Vol 1 (25) ◽  
pp. 140-149
Author(s):  
G.G. Parkhomenko ◽  
◽  
S.I. Kambulov ◽  
I.V. Bozhko ◽  
◽  
...  
Keyword(s):  
Technological Process ◽  
Rational Design ◽  
Climatic Conditions ◽  
Design Parameters ◽  
Coupling Device ◽  
Rational Design Parameters ◽  
High Level ◽  
Relationship Of ◽  
The Relationship

Choosing rational design parameters of the coupling device for multi-section aggregation of seeders, it is possible to ensure full loading of the power unit while maintaining quality indicators of the technological process at a sufficiently high level. Foreign aggregates are not suitable for use in the Russian Federation due to the different soil and climatic conditions. Purpose of the study: to develop an effective device for multi-section aggregation suitable for domestic modern seeding machines. Subject of the research: the relationship of design parameters and modes of operation of the device for multi-section aggregation of seeders with indicators of the technological process of sowing. A monographic survey of known structures has been carried out, a device for multi-section aggregation of seeding machines has been substantiated by the design and construction method, indicators of the technological process of sowing have been experimentally obtained. The developed coupling device for multi-section aggregation consists of a central frame resting on the wheels and articulated side sections: left and right, which fold when transporting the seeding unit. The total working width of the seeding unit is up to 12.5 meters. According to the research results, the quality of the technological process by the seeding devices meets the regulatory requirements. The instability of the total seeding (0.6–1.1 % for barley and 0.4–0.7 % for wheat) is within the tolerance (up to 3 percent); uneven seeding between devices 3.9–4.2 percent (barley) and 2.6–4.2 percent (wheat) corresponds to the norm (up to 5 percent). The number of seeds embedded at a predetermined depth of the soil corresponds to the required (not less than 80 percent) and was 81.8–83.9 percent for barley and 80.1–83.3 percent for wheat. Not embedded seeds were found in the soil.

Investigation of Squeeze Film Damping and Associated Loads

2017 ◽  
Author(s):  
Per Johansen ◽  
Niels C. Bender ◽  
Anders H. Hansen ◽  
Lasse Schmidt
Keyword(s):  
Squeeze Film ◽  
Design Parameters ◽  
Impact Loads ◽  
Fast Switching ◽  
Damping Effect ◽  
Squeeze Film Damping ◽  
Inherent Feature ◽  
Pressure Dependency ◽  
Gap Height ◽  
The Impact

Digital hydraulics have attracted attention towards fast switching valves and the increased focus on reliable fluid power entail that the lifetime of such valves is of great concern. An inherent feature of most valves for digital hydraulics is that of a mechanical end stop. Consequently, the squeeze film damping associated with end stops of switching valves is an interesting topic. This damping effect is perceived as beneficial for high lifetime and low impact sound, as the consequence of lowering the impact velocity at the mechanical end stops. In this paper the squeeze film damping effect is reviewed with a focus on maximum surface stresses. Using the Barus relation for viscosity-pressure dependency and different film geometries, the classical lubrication theory is applied together with the equation of motion, to obtain the gap height motion equation, both for the iso-viscous and piezo-viscous case. In consequence, this enable insights concerning the influence of piezo-viscosity on this damping effect. These models are used to investigate the loads, which the approaching surfaces experiences. Based on Hertzian theory, comparisons of impact loads and the dynamic squeeze loading are performed, whereby the relation between design parameters and the relative severity of these occurrences are analyzed.

An Experimental Investigation of Wave Impact Loads on a Slender Horizontal Cylinder

2014 ◽  
Author(s):  
Joseph F. Haley ◽  
Chris Swan ◽  
Richard Gibson
Keyword(s):  
Water Surface ◽  
Impact Load ◽  
Horizontal Cylinder ◽  
The Body ◽  
Impact Loads ◽  
Wave Impact ◽  
Wide Range ◽  
Wave Event ◽  
Vector Sum ◽  
The Impact

This paper concerns the difficulties arising in the prediction of the impact loads associated with an extreme wave event. A new set of experimental observations are presented. These concern the impact loads arising on a slender horizontal cylinder located at varying elevations above the still water level. The experimental observations incorporate a wide range of wave forms. In each case, data is provided describing (i) the incident water surface profiles, (ii) the incident fluid velocities and (iii) the load components acting on the cylinder. Comparisons between the measured data and the classical impact load solutions confirm a number of important departures. In particular, it is shown that as the wave becomes very steep (approaching the breaking limit) the vector sum of the horizontal and vertical velocity components at the water surface may deviate significantly from the normal to the local water surface. In such cases it becomes unclear exactly what direction the impact force acts. The present data suggests that this is, in part, dependent on the rate of inundation of the body. Furthermore, the present results also show that if the direction of the force is correct modelled, the variations in the predicted loading (or slamming) coefficient are much reduced.

scholarly journals APPLICATION OF KINEMATIC STABILITY ANALYSIS IN DETERMINING RATIONAL DESIGN PARAMETERS OF CAREER STEPS

2021 ◽  
Vol 445 (1) ◽  
pp. 135-143
Author(s):  
S. А. Sedina ◽  
G. B. Abdikarimova ◽  
A. A. Altayeva ◽  
N. D. Rakhimov
Keyword(s):  
Rational Design ◽  
Open Pit ◽  
Design Parameters ◽  
Optimal Parameters ◽  
Stability Parameters ◽  
Failure Patterns ◽  
Safe State ◽  
Rational Design Parameters ◽  
The Stability

The main factor that determines the stability of the pit benches in rocky and semi-rocky rocks is geological and structural since potential collapse prisms of a particular configuration are formed by differently oriented ruptured faults (cracks) with certain spatial relationships between themselves and the pit surface. Evaluation of possible planar, wedge-shaped, and overturning collapses of individual benches is carried out by analyzing the parameters of structural disturbances identified within the rock mass of the studied section of the open pit relative to the orientation of open pit edges. The article presents the results of the analysis of the kinematic stability of the optimal parameters of the benches on the example of the Kurzhunkul open pit, which ensures their stability on the limiting contour. A sequence of actions is proposed for determining the stability parameters of rock benches in a quarry. Performing a kinematic analysis based on the identified systems of cracks allows us to determine the probable failure patterns of the slopes of the benches and select the calculation schemes for their stability to substantiate their optimal parameters and make decisions on their stabilization. Geological and structural zoning of the quarry space according to this method allows analyzing the holding capacity of safety berms to control detected collapses, to highlight benches that need to be brought into a safe state with the determination of their stable parameters, and to recommend options for optimizing the design profile.

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