scholarly journals Dynamic Processes of Loader Cranes Manipulators with Excessive Backlashes and Elastic Damping in Their Hinges

2019 ◽  
Vol 64 (1) ◽  
pp. 7-14
Author(s):  
Alexander V. Lagerev ◽  
Igor A. Lagerev
Keyword(s):  
Mathematical Model ◽  
Dynamic Loading ◽  
Structural Design ◽  
Impact Load ◽  
Dynamic Processes ◽  
Effective Solution ◽  
Complete Elimination ◽  
Quantitative Characteristics ◽  
Motion Parameters ◽  
Oscillatory Processes

This research is aimed at developing a mathematical model and the methodology for computer simulation of hydraulically driven manipulators of mobile cranes having excessive backlashes in cylindrical joints. The authors proposed a structural design and considered the mechanism of reducing the additional impact load in the hinges by means of elastic damping of oscillatory processes. This method allows estimating the degree of influence of the backlash and stiffness of the elastic damper on the change in the quantitative characteristics of the dynamic loading of the manipulators metalwork and the motion parameters of the transported load. While in operation, the excessive backlashes may cause an increase in the level of dynamic loading of manipulators up to 2 times or more. However, the rational choice of the elastic dampers stiffness allows an effective solution to this problem to the point of complete elimination of the additional impact load.

TO THE STABILITY OF TANK VEHICLES IN THE BRAKE MODE

2019 ◽  
pp. 27-32
Author(s):  
Denys Popelysh ◽  
Yurii Seluk ◽  
Sergyi Tomchuk
Keyword(s):  
Mathematical Model ◽  
Control Systems ◽  
Distribution Systems ◽  
Traffic Accidents ◽  
Road Traffic ◽  
Center Of Mass ◽  
Dynamic Processes ◽  
Course Stability ◽  
The Stability ◽  
Tank Vehicles

This article discusses the question of the possibility of improving the roll stability of partially filled tank vehicles while braking. We consider the dangers associated with partially filled tank vehicles. We give examples of the severe consequences of road traffic accidents that have occurred with tank vehicles carrying dangerous goods. We conducted an analysis of the dynamic processes of fluid flow in the tank and their influence on the basic parameters of the stability of vehicle. When transporting a partially filled tank due to the comparability of the mass of the empty tank with the mass of the fluid being transported, the dynamic qualities of the vehicle change so that they differ significantly from the dynamic characteristics of other vehicles. Due to large displacements of the center of mass of cargo in the tank there are additional loads that act vehicle and significantly reduce the course stability and the drivability. We consider the dynamics of liquid sloshing in moving containers, and give examples of building a mechanical model of an oscillating fluid in a tank and a mathematical model of a vehicle with a tank. We also considered the method of improving the vehicle’s stability, which is based on the prediction of the moment of action and the nature of the dynamic processes of liquid cargo and the implementation of preventive actions by executive mechanisms. Modern automated control systems (anti-lock brake system, anti-slip control systems, stabilization systems, braking forces distribution systems, floor level systems, etc.) use a certain list of elements for collecting necessary parameters and actuators for their work. This gives the ability to influence the course stability properties without interfering with the design of the vehicle only by making changes to the software of these systems. Keywords: tank vehicle, roll stability, mathematical model, vehicle control systems.

scholarly journals Analysis on Force Transmission Characteristics of Two-Legged Shield Support under Impact Loading

2018 ◽  
Vol 2018 ◽  
pp. 1-10 ◽  
Author(s):  
Qing-liang Zeng ◽  
Zhao-sheng Meng ◽  
Li-rong Wan ◽  
Cheng-long Wang
Keyword(s):  
Structural Design ◽  
Load Transfer ◽  
Impact Load ◽  
Force Transmission ◽  
Full Account ◽  
Flexible Bodies ◽  
Powered Support ◽  
Structural Design Optimization ◽  
Hinge Points ◽  
The Impact

To study the load transfer characteristics of a two-legged shield powered support, a numerical simulation model of the support was established using the multibody dynamics software ADAMS. The model took full account of the hydraulic-elastic deformation characteristics of the support, as a series spring-damper system was used to replace the leg and the equilibrium jack. The canopy, goaf shield, lemniscate bars, and equilibrium jack are equivalent to flexible bodies. The setting force of the leg was provided by the preload of the equivalent spring, the static roof load was simulated using a slope signal, and the impact load was simulated using a step signal. Using the model, the impact and excitation effects of each hinge joint of the support were analyzed under different impact load conditions across the canopy. The results show that the location of the impact load affects the force transmissions of all hinge points of the support. Both the impact effect and the excitation effect are at a minimum when the impact force is located near the leg action line. These results are useful for the adaptive control and structural design optimization of the support.

Dynamic Loading Approach for Structural Evaluation of Ultra Large Container Carriers

2005 ◽  
Author(s):  
Bill Shi ◽  
Donald Liu ◽  
Christopher Wiernicki
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Dynamic Loading ◽  
Impact Load ◽  
Failure Mechanisms ◽  
Direct Calculation ◽  
Element Analysis ◽  
Design Philosophy ◽  
Non Linear ◽  
Large Container

The emerging global economic needs are driving the designs for the next generation of ocean going vessels. Current ultra-large container carrier (10,000 TEU plus) designs are considerably larger and more complex than any currently in service. Proper and rational classification assessment requires that first principles based direct calculation methods be used to augment the standard classification review. The design philosophy behind the ABS Dynamic Loading Approach enables comprehensive identification of potential failure mechanisms. The scope of the necessary engineering assessment encompass full-ship finite element analysis under non-linear sea loads, spectral fatigue analysis, finite element lashing analysis, free and forced vibration analysis, and transient and impact load analysis. This paper describes key aspects of the DLA design philosophy such as non-linear sea loads, load combinations, various applications derived from full-ship finite element analysis. Several examples are given to highlight some critical failure mechanisms to be considered for ultra-large container carriers.

Simulation of oscillatory processes in the MVSTUDIUM package

2022 ◽  
Vol 14 (4) ◽  
pp. 139-148
Author(s):  
Aleksandr Poluektov ◽  
Konstantin Zolnikov ◽  
V. Antsiferova
Keyword(s):  
Mathematical Model ◽  
Friction Force ◽  
Computer Models ◽  
3D Models ◽  
Oscillatory Process ◽  
Suspension Point ◽  
Factors Affecting ◽  
2D And 3D ◽  
The Mathematical Model ◽  
Oscillatory Processes

The mathematical model and algorithms of oscillatory movements are considered. Various factors affecting the oscillatory process are considered. Oscillatory movements are constructed in the MVSTUDIUM modeling environment. The schemes of three computer models demonstrating oscillatory processes are determined: a model of a pendulum with a non-movable suspension point, a model of a pushing pendulum with friction force and a model of a breaking pendulum. Classes are being built to execute models with embedded properties, as well as with the ability to export the created classes to other models, and embed classes created by the program developer into the model. Creation of 2D and 3D models of oscillatory processes, an experiment behavior map and a virtual stand.

scholarly journals Generalization of research results on the dynamics of continuous wide-strip hot-rolling mills

2018 ◽  
pp. 275-289
Author(s):  
V.V. Verenev
Keyword(s):  
Mathematical Model ◽  
Hot Rolling ◽  
Large Data ◽  
Dynamic Processes ◽  
Technological Parameters ◽  
Rolling Moment ◽  
Rolling Mills ◽  
Wide Strip ◽  
The Impact ◽  
First Time

The aim of the work is to summarize the results of experimental-industrial and theoretical studies of dynamic processes in wide-strip hot rolling mills 1680, 1700, 2000 and 2500. We describe the methods of collecting, storing, identifying, visualizing and mathematical processing of large data arrays, which made it possible to establish new laws and correlations of technological parameters. New results related to the peculiarities of transient processes, their patterns and the use of the latter for the purpose of diagnosing technology and equipment condition are presented. Vibrodynamic processes are described when the strip is captured by the rollers. For the first time, a correlation between the maximum peak moment when the strip is captured and the static rolling moment on the 1680 mill is obtained and substantiated by measuring and statistical modeling. A new mathematical model of the roll line is developed, incorporating the equations of dynamic processes in gears and axles of the gearbox. For the first time, the dynamics of the formation of intercellular tensions in the process of sequential filling and release with a 6-cell band is shown. A complete mathematical model and a computer program for the dynamic interaction of six-group stands of a rolling strip have been developed. A new line of research has been proposed, which includes the search, substantiation and testing of new methods and methods for diagnosing the technical condition of rolling mills based on the use of transients and their parameters in various modes of equipment operation. Proposed and tested in industrial conditions at the mills 1680 and 1700-M are effective ways to reduce the impact loads during the period of the strip capture by the rollers.

Design of a New Multi-Channel High-Low Pressure Micro-Ejection System

2011 ◽  
Vol 189-193 ◽  
pp. 4313-4317
Author(s):  
Wei Yang ◽  
Qiang Yin ◽  
Kun Wang Niu ◽  
Jiao Zhang ◽  
Wen Dong Zhang
Keyword(s):  
Mathematical Model ◽  
Numerical Analysis ◽  
Structural Design ◽  
Structural Characteristics ◽  
Low Pressure ◽  
Classical Trajectory ◽  
Design Methods ◽  
Analysis And Design ◽  
Bullet Velocity

According to the structural characteristics of the multi-channel high-low pressure micro-ejection system,this paper sets up mathematical model of the trajectory based on the classical trajectory theory,makes numerical analysis to prove the rationality of the structural design,tests the pressure and bullet velocity of the launching system.The results show that the analysis and design methods of the multi-channel high-low pressure micro-ejection system are reasonable and reliable.

Research on Vibration Bench of Vehicle Suspension by Finite Element

2013 ◽  
Vol 312 ◽  
pp. 258-261
Author(s):  
Xian Yu Liu
Keyword(s):  
Mathematical Model ◽  
Finite Element ◽  
Stress Field ◽  
Structural Design ◽  
Transformation Process ◽  
Vehicle Suspension

By establishing and analyzing mathematical model for vibration bench of vehicle suspension, this paper optimized and simulated vibration bench of vehicle suspension based on finite element. As a result, the paper got stress field and its distribution during transformation process and set a foundation for structural design of vibration bench of suspension.

Design Method of Self-Loading Device of the Side-Crane Used for Container

2012 ◽  
Vol 466-467 ◽  
pp. 951-955
Author(s):  
Jun Qing Zhan ◽  
Xiao Mei Feng ◽  
Li Shun Li ◽  
Xiang De Meng
Keyword(s):  
Mathematical Model ◽  
Structural Design ◽  
Design Method ◽  
The Self ◽  
Design Calculation ◽  
Force Analysis ◽  
Loading Device ◽  
Calculation Results ◽  
The Mathematical Model ◽  
Flat Ground

The self-loading device used for side-crane is put forward. Its structure is presented. Based on the force analysis when the side-crane works at flat ground, the mathematical model is established when the crane working at uneven ground. And the design calculation is performed. The self-loading device’s optimal design is accomplished. Based on the above calculation results, the self-loading prototype is manufactured. And the design method can be adopted to the similar equipment’s structural design.

MODELLING THE INTERACTION BETWEEN RAILWAY WHEEL AND RAIL

Transport ◽  
2008 ◽  
Vol 23 (3) ◽  
pp. 236-239 ◽  
Author(s):  
Stasys Dailydka ◽  
Leonas Povilas Lingaitis ◽  
Sergey Myamlin ◽  
Vladimir Prichodko
Keyword(s):  
Mathematical Model ◽  
Operating Conditions ◽  
Rolling Stock ◽  
Dynamic Processes ◽  
Running Speed ◽  
Railway Wheel ◽  
The Real ◽  
The Impact ◽  
Railway Rolling Stock

The article presents a mathematical model for assessing the real operating conditions of railway rolling stock, taking into account the situations when the wheel loses contact with rail. The obtained amplitudinal fluctuation characteristics depend on the set roughness function and the running speed of the wheel. When calculating dynamic processes, the contact between wheel and rail should be considered unstable. With the increase of speed, the impact of this instability increases.

PID Control for Magnetorheological Elastomer Absorber with Impact Load

2011 ◽  
Vol 121-126 ◽  
pp. 1734-1738 ◽  
Author(s):  
Jie Fu ◽  
Miao Yu ◽  
Zhi Wei Xing
Keyword(s):  
Numerical Simulation ◽  
Mechanical Property ◽  
Mathematical Model ◽  
Control Strategy ◽  
Pid Control ◽  
Pid Controller ◽  
Impact Load ◽  
Variable Stiffness ◽  
Impact Testing ◽  
Magnetorheological Elastomer

In this paper, a semi-active impact control system, which consists of a new Magnetorehological elastomer (MRE) absorber with variable stiffness, is proposed and its vibration control with impact load is investigated. An impact testing platform is established and mechanical property of fabricated MRE is tested. Based on Newton’s law the appropriate mathematical model of MRE absorber system is established. PID controller for MRE absorber system is designed to reduce the effect of impact load. Finally, the effectiveness of control strategy is verified by numerical simulation.

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