Dynamic analysis on rigid-flexible coupled multi-body system with a few flexible components

This document researches on the improved deployable planar truss mechanism design and builds an dynamic equation of the model based on Lagrange equation in the multi-body system dynamic theory. The dynamic model is established to simulate the motion of the system and calculate the force condition of members respectively by ADAMS. Finally, the significant references for the elasto-dynamic analysis and optimization design of the truss mechanism will be provided.

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Dualities in the Analysis of Mechanisms With Multiple Loops and Parallel Mechanisms With Loops in Their Connecting Chains

Volume 2: 28th Biennial Mechanisms and Robotics Conference, Parts A and B ◽

10.1115/detc2004-57039 ◽

2004 ◽

Author(s):

Koichi Sugimoto

Keyword(s):

Dynamic Analysis ◽

Parallel Mechanism ◽

Jacobian Matrix ◽

Parallel Mechanisms ◽

Body System ◽

Multi Body ◽

The Relationship

There exists a duality relationship between a twist and a wrench in the dynamics of a mechanism or a multi-body system. Using this relationship, the coordinate-free expressions for the dynamic analysis of multi-loop mechanisms is derived. In the analysis, a Jacobian matrix expressing the relationship among loops is defined, and it is clarified, by using this matrix, that both twists and wrenches can be easily analyzed based on the duality relationship among them. A parallel mechanism having connecting chains with loops is also analyzed, and it is shown that the same procedure can be applied to a parallel mechanism with connecting chains, each loop of which has a motion space that is different from that of the mechanism.

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Dynamic analysis and vibration control of a multi-body system using MSC Adams

Latin American Journal of Solids and Structures ◽

10.1590/1679-78251598 ◽

2015 ◽

Vol 12 (8) ◽

pp. 1505-1524 ◽

Cited By ~ 1

Author(s):

M. Naushad Alam ◽

Adnan Akhlaq ◽

Najeeb ur Rahman

Keyword(s):

Dynamic Analysis ◽

Vibration Control ◽

Body System ◽

Multi Body

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Wear predictions for cams in line contacts based on multidisciplinary simulation

Industrial Lubrication and Tribology ◽

10.1108/ilt-04-2014-0034 ◽

2015 ◽

Vol 67 (2) ◽

pp. 159-165 ◽

Cited By ~ 2

Author(s):

Wenjie Qin ◽

Lunjing Duan

Keyword(s):

Finite Element ◽

Numerical Calculation ◽

Dynamic Analysis ◽

Boundary Lubrication ◽

Contact Analysis ◽

System Dynamic ◽

Body System ◽

Content Type ◽

Cam Follower ◽

Multi Body

Purpose – This paper aims to present the model and method involving multi-body system dynamic analysis, finite element quasi-statics contact analysis and numerical calculation of elastohydrodynamic lubrication (EHL), according to the cam wear prediction using Archard’s model. Cam–follower kinematic pairs always work under wear because of concentrated contacts. Given that a cam and follower contact often operates in the mixed or boundary lubrication regime, simulation of cam wear is a multidisciplinary problem including kinematic considerations, dynamic load and stress calculations and elastohydrodynamic film thickness evaluations. Design/methodology/approach – Multi-body system dynamic analysis, finite element quasi-statics contact analysis and numerical calculation of EHL are applied to obtain the dynamic loads, the time histories of contact pressure and the oil film thicknesses in cam–follower conjunctions to predict cam wear quantitatively. Findings – The wear depth of the cam in the valve train of a heavy-load diesel engine is calculated, which is in good agreement with the measured value in the practical test. The results show that the cam–tappet pair operates under a mixed lubrication or boundary lubrication, and the wear depths on both sides of the cam nose are extremely great. The wear of these points can be decreased significantly by modifying the local cam profile to enlarge the radii of curvature. Originality/value – The main value of this work lies in the model and method involving multi-body system dynamic analysis, finite element quasi-statics contact analysis and numerical calculation of EHL, which can give good prediction for the wear of cam.

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Dynamic Performance of High-Speed Electric Multiple Unit within Multi-Body System Simulation

Recent Patents on Mechanical Engineering ◽

10.2174/2666145412666190923104415 ◽

2019 ◽

Vol 12 (4) ◽

pp. 339-349

Author(s):

Junguo Wang ◽

Daoping Gong ◽

Rui Sun ◽

Yongxiang Zhao

Keyword(s):

High Speed ◽

Rapid Development ◽

Dynamic Performance ◽

Body System ◽

High Speed Railway ◽

Evaluation Indexes ◽

Actual Operation ◽

Multiple Unit ◽

The Stability ◽

Multi Body

Background: With the rapid development of the high-speed railway, the dynamic performance such as running stability and safety of the high-speed train is increasingly important. This paper focuses on the dynamic performance of high-speed Electric Multiple Unit (EMU), especially the dynamic characteristics of the bogie frame and car body. Various patents have been discussed in this article. Objective: To develop the Multi-Body System (MBS) model of EMU, verify whether the dynamic performance meets the actual operation requirements, and provide some useful information for dynamics and structural design of the proposed EMU. Methods: According to the technical characteristics of a typical EMU, a MBS model is established via SIMPACK, and the measured data of China high-speed railway is taken as the excitation of track random irregularity. To test the dynamic performance of the EMU, including the stability and safety, some evaluation indexes such as wheel-axle lateral forces, wheel-axle lateral vertical forces, derailment coefficients and wheel unloading rates are also calculated and analyzed in detail. Results: The MBS model of EMU has better dynamic performance especially curving performance, and some evaluation indexes of the stability and safety have also reached China’s high-speed railway standards. Conclusion: The effectiveness of the proposed MBS model is verified, and the dynamic performance of the MBS model can meet the design requirements of high-speed EMU.

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Impact of Increased Travel Speed of a Transportation Set on the Dynamic Parameters of a Mine Suspended Monorail

Energies ◽

10.3390/en14061528 ◽

2021 ◽

Vol 14 (6) ◽

pp. 1528

Author(s):

Kamil Szewerda ◽

Jarosław Tokarczyk ◽

Andrzej Wieczorek

Keyword(s):

Computational Model ◽

Travel Speed ◽

Body System ◽

Emergency Braking ◽

System Method ◽

Underground Coal Mines ◽

Program Environment ◽

Underground Transportation ◽

Multi Body ◽

Transportation Routes

The method of increasing the efficiency of using one of the most common means of auxiliary transport in underground coal mines—suspended monorails—is presented. Increase of velocity is one of the key parameters to improve the efficiency and economical effect related with the underground auxiliary transport. On the other hand, increasing the velocity results in bigger value of force acting on the suspended monorail route and its suspensions. The most important issue during increasing the velocity is ensuring the required safety for the passengers and not overloading the infrastructure. In order to analyze how increasing velocity influences the level of loads of the route suspension and the steel arch loads, the computational model of suspended monorail was developed. The computational model included both the physical part (embedded in the program environment based on the Multi-Body System method) and the components of the monorail control system. Two independent software environments were cooperating with each other through the so-called co-simulation. This model was validated on the base of results obtained on the test stand. Then, the numerical simulations of emergency braking with different values of velocity were conducted, which was not possible with the use of physical objects. The presented study can be used by the suspended monorail’s producers during the designing process, and leads to increase the safety on underground transportation routes.

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