Science topic

# Multibody System Dynamics - Science topic

Multibody System Dynamics, approaches to compute equations of motion of an multibody system, MR.

Questions related to Multibody System Dynamics

Hello all,

I am working on a thermal model in Ansys Fluent 2019 R3, with the geometries of 4 cylinders of different lengths. Three cylinders form an inner tube and one cylinder as an outer tube.

All are considered as a single part.

It is a multiphase model with one material in the inner tubes and another material in the outer tube. I have chosen inner tubes as one cell zone and outer tube as another cell zone. When I gave inlets with a certain velocity and the heat boundary condition on one wall of the inner tubes (mostly first or second tube). I cannot see any heat flow. Moreover, I see a phase distribution issue even after mentioning different cell zones.

Could anyone suggest to me or help me, what could be the reasons for these issues? I have revised many videos and multiple papers regarding the problem. But, I see no useful information.

Any sought of help is highly appreciated.

Thank you

Rajesh

I am looking for an open source software to carry out generic multibody simulations.

A mechanism is moving in a particular pattern. There is a real time video of the same with red color markers are stick to each links. Is there any image processing tool or software which can capture the movement of links and give its change in position, velocity and acceleration? So that the results can be used to co relate rigid body/ multibody dynamic model results.

I have started a research on the modeling of multibody systems dynamics, and since dynamics mean to determine the Differential Equations of Motion, i am called to make the resolution of these OEM.

I need to know how to do so, so i started working on an easy example, but i find it difficult because i have no background on mathematics especially numerical integration.

My question is how to proceed to solve a DAE numerically using one of these methods ; Runge kutta, Adams - Bashford or Moulton, Central differences or Gaussian method?

Actually, I was reading Shabana’s Book: Computational dynamics, John Wiley & Sons. 2010. As I'm investigating the dynamics of a multi-body system (having rigid and flexible structures).

*This code was introduced in chapter 9 of Shabana's book with some demonstrations of different parts of the code and it's usage. Yet, to my best knowledge, it was not mentioned from where to get this code*.**I would like to know where may I find this code, and/or other alternatives with similar or more capabilities?**Hi,

I built a Simulink vehicle model with Dugoff's tire model that requires two parameters to calculate Fx and Fy; namely, the longitudinal stiffness and the cornering stiffness. Now I would like to verify my Simulink model by comparing the results with MSC ADAMS. ADAMS does not have Dugoff's tire model. How can I get these two parameters from ADAMS ?

why we prefer sliding joints in bridges?

Hi everyone.

I try to find some simple method to measure body-posture. We know a lot of them, but they are either low objective (aspect-based methods) or very difficult and expensive (Formetric 4D). Some advice...?

I know about nice resarch from Australia (https://bmcmusculoskeletdisord.biomedcentral.com/articles/10.1186/1471-2474-9-113), but I miss some more informations and all my attempts to contact authors ended up failing.

Thanks in advance, Lenka

what are the implications behind choosing Extraction and Rotation methods while doing EFA?

Applications of Differential-Algebraic Equations: Examples and Benchmarks

Editors:

Steve Campbell, Achim Ilchmann, Volker Mehrmann, and Timo Reis

The planned volume in the DAE-FORUM series will encompass prototypical, innovative and emerging examples and benchmarks of DAEs such as electrical networks, chemical reactors, multibody systems, multiphysics models, to name but a few. Applications may be to a particular problem or to another area of mathematics or science.

Each article (15-40 pages) should start with a modelling section explaining whether the model is prototypical and for which applications it is used, followed by a mathematical analysis, and - if appropriate - a discussion of the numerical aspects including simulation. Benchmark examples are welcome. All chapters in this upcoming issue of DAE-F will be published “OnlineFirst” with an individual DOI, i.e. contributions are visible and citable already before completion of the book.

We have a number of authors already, but we are open to consideration of additional contributors, especially in new applications. If you would like to suggest any names for our consideration, please feel free to suggest them along with their area of application.

If you are interested in contributing, you may submit your manuscript directly via the link http://www.editorialmanager.com/daef/default.aspx until August 1, 2017, choosing the article type “Special Issue: Benchmarks in DAEs” from the drop down menu in the submission system. If you would like to discuss your project with us, please feel free to contact any of the four editors.

Note: If the Springer link is not active yet it will be very soon?

I am looking for a software which will help me analyse simple to complex mechanisms with ease. It will be advantageous such software also support co-simulations.

Hello.

I have a mechanical system that can inflate a rubber film by air (in real). My rubber film is not uniform and when inflated it deforms differently based on the thickness. Now, I need to model how the deformed shaped will look during inflation and the active pressure of different area on the rubber surface.

Any idea?

Thanks in advance!

Except John Sterman Book entitled “Business Dynamics: Systems Thinking and Modeling for a Complex World” that I use it as a master Reference in our class, what books are useful for teaching Purposes?

Do you know a book with many Teaching Examples and Exercises of Model that has Hierarchy of complexity for Student?

In your University what books are as a main references and basis of content?

Having a family of vector fields (non-linear, 2d), depending on several control parameters with degenerate fixed points for some values of these, how can we determine the bifurcation type from the normal form?

I have intrinsic yaw-pitch-roll data for the initial and final position of a rigid body and I want to find the yaw-pitch-roll values halfway. Can I just linearly interpolate the yaw-pitch-roll values?

I would imagine this is done quite often in robotics, 3D graphics, gait analysis and other multibody mechanics applications, so any insight would be appreciated.

Thanks.

I want to model a cart with wheels in MATLAB SimMechanics and it is important for me that use wheels, not a prismatic joint instead of wheels.

And then I can apply torque by a DC motor to wheels.

Looking for subroutine to separate coordinate into depended and in-depended in the case of multibody analysis field.

I would like to transfer transient analysis results from Finite Element Analysis Tool to MultiBody Dynamic Tool.

What is the difference between Prismatic (linear) joint and screw joint in both kinematic and dynamic? Could I use the prismatic joint to get the same behavior of screw joint?