Stick-slip algorithm in a tangential contact force model for multi-body system dynamics

This work deals with a methodology to assess the influence of the spherical clearance joints in spatial multibody systems. The methodology is based on the Cartesian coordinates, being the dynamics of the joint elements modeled as impacting bodies and controlled by contact forces. The impacts and contacts are described by a continuous contact force model that accounts for geometric and mechanical characteristics of the contacting surfaces. The contact force is evaluated as function of the elastic pseudo-penetration between the impacting bodies, coupled with a nonlinear viscous-elastic factor representing the energy dissipation during the impact process. A spatial four bar mechanism is used as an illustrative example and some numerical results are presented, being the efficiency of the developed methodology discussed in the process of their presentation. The results obtained show that the inclusion of clearance joints in the modelization of spatial multibody systems significantly influences the prediction of components’ position and drastically increases the peaks in acceleration and reaction moments at the joints. Moreover, the system’s response clearly tends to be nonperiodic when a clearance joint is included in the simulation.

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Hertz Contact Force Model With Permanent Indentation in Impact Analysis of Solids

18th Design Automation Conference: Volume 2 — Geometric Modeling, Mechanisms, and Mechanical Systems Analysis ◽

10.1115/detc1992-0189 ◽

1992 ◽

Author(s):

Hamid M. Lankarani ◽

Parviz E. Nikravesh

Keyword(s):

Contact Force ◽

Impact Analysis ◽

Equations Of Motion ◽

Solid Particles ◽

Hertzian Contact ◽

Contact Period ◽

Force Model ◽

Unknown Parameters ◽

Contact Force Model ◽

Energy And Momentum

Abstract A continuous analysis method for the direct-central impact of two solid particles is presented. Based on the assumption that local plasticity effects are the sole factor accounting for the dissipation of energy in impact, a Hertzian contact force model with permanent indentation is constructed. Utilizing energy and momentum considerations, the unknown parameters in the model are analytically evaluated in terms of a given coefficient of restitution and velocities before impact. The equations of motion of the two solids may then be integrated forward in time knowing the variation of the contact force during the contact period. For Illustration, an impact of two soft metallic particles is studied.

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Experimental Validation of a Volumetric Planetary Rover Wheel/Soil Interaction Model

Volume 1: 15th International Conference on Advanced Vehicle Technologies; 10th International Conference on Design Education; 7th International Conference on Micro- and Nanosystems ◽

10.1115/detc2013-13486 ◽

2013 ◽

Author(s):

Willem Petersen ◽

John McPhee

Keyword(s):

Contact Force ◽

Interaction Model ◽

Contact Model ◽

Soil Parameters ◽

Model Parameters ◽

Force Model ◽

Normal Contact ◽

Planetary Rover ◽

Normal Contact Force ◽

Contact Force Model

For the multibody simulation of planetary rover operations, a wheel-soil contact model is necessary to represent the forces and moments between the tire and the soft soil. A novel nonlinear contact modelling approach based on the properties of the hypervolume of interpenetration is validated in this paper. This normal contact force model is based on the Winkler foundation model with nonlinear spring properties. To fully define the proposed normal contact force model for this application, seven parameters are required. Besides the geometry parameters that can be easily measured, three soil parameters representing the hyperelastic and plastic properties of the soil have to be identified. Since it is very difficult to directly measure the latter set of soil parameters, they are identified by comparing computer simulations with experimental results of drawbar pull tests performed under different slip conditions on the Juno rover of the Canadian Space Agency (CSA). A multibody dynamics model of the Juno rover including the new wheel/soil interaction model was developed and simulated in MapleSim. To identify the wheel/soil contact model parameters, the cost function of the model residuals of the kinematic data is minimized. The volumetric contact model is then tested by using the identified contact model parameters in a forward dynamics simulation of the rover on an irregular 3-dimensional terrain and compared against experiments.

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Dynamic analysis of planar mechanical systems with clearance joints using a new nonlinear contact force model

Journal of Mechanical Science and Technology ◽

10.1007/s12206-016-0308-1 ◽

2016 ◽

Vol 30 (4) ◽

pp. 1537-1545 ◽

Cited By ~ 27

Author(s):

Xupeng Wang ◽

Geng Liu ◽

Shangjun Ma

Keyword(s):

Dynamic Analysis ◽

Contact Force ◽

Mechanical Systems ◽

Force Model ◽

Clearance Joints ◽

Contact Force Model ◽

Nonlinear Contact

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With the Backlash Dynamics Simulation of a Crank-Slider Mechanism of the Internal Combustion Engine

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.215-216.1081 ◽

2012 ◽

Vol 215-216 ◽

pp. 1081-1084

Author(s):

Shao Jun Bo ◽

Kui Ji ◽

Juan Tian

Keyword(s):

System Dynamics ◽

Combustion Engine ◽

Dynamics Simulation ◽

Kinematic Pair ◽

Body System ◽

Nonlinear Characteristics ◽

Preliminary Study ◽

Multi Body ◽

Dynamics Models ◽

Crank Mechanism

On the basis of flexible multi-body system dynamics theory, we built flexible multi-body system dynamics models which include a backlash, and to a slider-crank mechanism as the research object, we made a preliminary study on the effect on the flexible components and the backlash of the kinematic pair on mechanical system dynamics characteristics. To consider the backlash of the kinematic pair and component of flexible space can show a preliminary research on the dynamic simulation, and focus on the backlash, friction and gravity field to influence in the dynamic characteristics of the system. The simulation results show that, due to the existence of backlash made the two components frequent collision in the process of the stretching, clearance, flexible and friction are closed, make the system nonlinear characteristics increased.

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Numerical simulation of a sinking ship scenario based on archaeological records

Archaeologia Adriatica ◽

10.15291/archeo.3393 ◽

2021 ◽

Vol 14 (1) ◽

Author(s):

Smiljko Rudan ◽

Irena Radić Rossi

Keyword(s):

Numerical Simulation ◽

System Dynamics ◽

Archaeological Site ◽

3D Modelling ◽

Body System ◽

Standard Practice ◽

The Past ◽

Modern Engineering ◽

The Creation ◽

Multi Body

Over the past decade, photogrammetric recording and virtual 3D modelling have evolved as a standard practice in documenting shipwreck sites. Exploiting the same methods, we can attempt to virtually reconstruct the dynamics of an accident leading to the creation of an archaeological site. By applying modern engineering tools capable of deploying multi-body system dynamics to simulate the damaging, capsizing and/or sinking of a ship, we can model and analyse the various possible scenarios of an incident occurring to an ancient merchantman. Subsequently, we can establish the correlation between the characteristics of the actual shipwreck site, and the outcome of the numerical simulation of the assumed scenario.

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