Continuous contact force model with an arbitrary damping term exponent: Model and discussion

2021 ◽  
Vol 159 ◽  
pp. 107808
Author(s):  
Jie Zhang ◽  
Can Huang ◽  
Lei Zhao ◽  
Jiejian Di ◽  
Guangping He ◽  
...  
Keyword(s):  
Contact Force ◽  
Force Model ◽  
Damping Term ◽  
Continuous Contact ◽  
Contact Force Model

scholarly journals Dynamics of Multibody Systems With Spherical Clearance Joints

2005 ◽  
Author(s):  
P. Flores ◽  
J. Ambro´sio ◽  
J. C. P. Claro ◽  
H. M. Lankarani
Keyword(s):  
Contact Force ◽  
Multibody Systems ◽  
Contact Forces ◽  
Force Model ◽  
Clearance Joints ◽  
Continuous Contact ◽  
Clearance Joint ◽  
Contact Force Model ◽  
Dynamics Of Multibody Systems ◽  
The Impact

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.

A continuous contact force model for impact analysis

2022 ◽  
Vol 168 ◽  
pp. 108739
Author(s):  
Jie Zhang ◽  
Xu Liang ◽  
Zhonghai Zhang ◽  
Guanhua Feng ◽  
Quanliang Zhao ◽  
...  
Keyword(s):  
Contact Force ◽  
Impact Analysis ◽  
Force Model ◽  
Continuous Contact ◽  
Contact Force Model

scholarly journals A continuous contact force model of planar revolute joint based on fitting method

2017 ◽  
Vol 9 (2) ◽  
pp. 168781401769047
Author(s):  
Yuntao Li ◽  
Qiquan Quan ◽  
Dewei Tang ◽  
Zhonghong Li ◽  
Zongquan Deng
Keyword(s):  
Contact Force ◽  
Contact Stiffness ◽  
Elastic Force ◽  
Contact Model ◽  
Force Model ◽  
Damping Force ◽  
Revolute Joint ◽  
Continuous Contact ◽  
Contact Force Model ◽  
Fitting Method

Both the process of eliminating the clearance in joints and the contact–impact process involve movement of a clearance mechanism, which may reduce transmission accuracy and lengthen the response time. An appropriate continuous contact force model is able to describe the contact phenomena of a joint with clearance in a facile manner. However, two main problems still should be solved in building the continuous contact force model. First, the elastic force parts in previous continuous contact force models for a revolute joint were established by amending the force exponent of the Hertz spherical contact model or by the modified Winkler contact model. Nevertheless, the force exponent is usually given by experience, and the thickness of the elastic layer in the Winkler theory is difficult to determine. Second, for the previous damping force parts of a revolute joint, the hysteretic damping coefficients were obtained by substituting the stiffness coefficient with the contact stiffness of revolute joint directly instead of using the energy conservation method for the complicated form of elastic force model. A feasible continuous contact force model based on a fitting method was proposed to avoid these problems. According to the experimental results, the continuous contact force model can be used to predict the contact characteristics of a planar revolute joint in a facile manner.

Dynamic characteristics of planar linear array deployable structure based on scissor-like element with joint clearance using a new mixed contact force model

2016 ◽  
Vol 230 (18) ◽  
pp. 3161-3174 ◽  
Author(s):  
Bo Li ◽  
San-Min Wang ◽  
Ru Yuan ◽  
Xiang-Zhen Xue ◽  
Chang-Jian Zhi
Keyword(s):  
Contact Force ◽  
Dynamic Characteristics ◽  
Dynamic Performance ◽  
Equations Of Motion ◽  
Contact Model ◽  
Joint Clearance ◽  
Force Model ◽  
Continuous Contact ◽  
Deployable Structure ◽  
Contact Force Model

This paper aims at investigating precisely the dynamic performance of deployable structure constituted by scissor unit mechanisms with clearance joint. Based on the motion law in real joints, the contact model is established using an improved Gonthier nonlinear continuous contact force model, and the friction effect is considered using LuGre model. Moreover, the resulting contact force is suitable to be included into the generalized force of the equations of motion of a multibody system and contributes to replace motion constraints. In the sequel of this process, the effect of joint clearance is successfully introduced into the dynamical model of scissor deployable structure and the dynamic characteristics of deployable structure with joint clearance are obtained using a direct default correction method, which can directly modify the coordinates and speed of the system to avoid the numerical results divergence. Also, the new hybrid contact force model of revolute joint clearance is verified through comparing with the original model. The numerical simulation results show that the improved contact model proposed here has the great merit that predicts the dynamic behavior of scissor deployable structure with joint clearance.

A Contact Force Model With Hysteresis Damping for Impact Analysis of Multibody Systems

1989 ◽  
Author(s):  
H. M. Lankarani ◽  
P. E. Nikravesh
Keyword(s):  
Contact Force ◽  
Impact Analysis ◽  
Multibody System ◽  
Particle Collision ◽  
Dissipated Energy ◽  
Particle Model ◽  
Force Model ◽  
Continuous Contact ◽  
Contact Force Model ◽  
The Impact

Abstract A continuous contact force model for the impact analysis of a two-particle collision is presented. The model uses the general trend of the Hertz contact law. A hysteresis damping function is encorporated in the model which represents the dissipated energy in impact. The parameters in the model are determined, and the validity of the model is established. The model is then generalized to the impact analysis between two bodies of a multibody system. A continuous analysis is performed using the equations of motion of either the multibody system or an equivalent two-particle model of the colliding bodies. For the latter, the concept of effective mass is presented in order to compensate for the effects of joint forces in the system. For illustration, the impact situation between a slider-crank mechanism and another sliding block is considered.

A Contact Force Model With Hysteresis Damping for Impact Analysis of Multibody Systems

1990 ◽  
Vol 112 (3) ◽  
pp. 369-376 ◽  
Author(s):  
H. M. Lankarani ◽  
P. E. Nikravesh
Keyword(s):  
Contact Force ◽  
Impact Analysis ◽  
Multibody System ◽  
Particle Collision ◽  
Dissipated Energy ◽  
Particle Model ◽  
Force Model ◽  
Continuous Contact ◽  
Contact Force Model ◽  
The Impact

A continuous contact force model for the impact analysis of a two-particle collision is presented. The model uses the general trend of the Hertz contact law. A hysteresis damping function is incorporated in the model which represents the dissipated energy in impact. The parameters in the model are determined, and the validity of the model is established. The model is then generalized to the impact analysis between two bodies of a multibody system. A continuous analysis is performed using the equations of motion of either the multibody system or an equivalent two-particle model of the colliding bodies. For the latter, the concept of effective mass is presented in order to compensate for the effects of joint forces in the system. For illustration, the impact situation between a slider-crank mechanism and another sliding block is considered.

Non-linear continuous-contact-force model for low-speed front-to-rear vehicle impact

2007 ◽  
Vol 221 (10) ◽  
pp. 1197-1208 ◽  
Author(s):  
I Han
Keyword(s):  
Contact Force ◽  
High Speed ◽  
Force Model ◽  
Injury Biomechanics ◽  
Low Speed ◽  
Continuous Contact ◽  
Acceleration Pulse ◽  
Rear Impact ◽  
Contact Force Model ◽  
Non Linear

The most common kind of vehicular accident is the low-speed front-to-rear impact that results in a high proportion of insurance claims and whiplash-associated disorders. The low-speed collisions have specific characteristics that differ from high-speed collisions and must be treated differently. This paper presents a fundamental non-linear continuous-contact-force model for the low-speed front-to-rear impact to simulate the accelerations, the velocities, and the contact force as functions of time. A smoothed Coulomb frictional force is used to represent the effect of braking, which was found to be significant in simulating low-speed front-to-rear impact. The intervehicular contact force is modelled using non-linear damping and spring elements with coefficients and exponents. This paper presents a method of estimating analytically the stiffness and damping coefficients. The exponent of the non-linear contact force model was determined to match the overall acceleration pulse shape and magnitude. The model can be used to determine ∇ V values and peak accelerations for the purpose of accident reconstruction and for injury biomechanics studies.

A Novel Continuous Contact Force Model for Multibody Dynamics

2011 ◽  
Author(s):  
Margarida Machado ◽  
Paulo Flores
Keyword(s):  
Kinetic Energy ◽  
Multibody Dynamics ◽  
Contact Force ◽  
Contact Process ◽  
Coefficient Of Restitution ◽  
Dissipated Energy ◽  
Damping Factor ◽  
Force Model ◽  
Continuous Contact ◽  
Contact Force Model

A general and comprehensive analysis on the continuous contact force models in multibody dynamics is presented and a novel contact force model is proposed. The force models are developed based on the foundation of the Hertz law together with a hysteresis damping parameter that accounts for the energy dissipation during the contact process. In a simple way, these contact force models are based on the analysis and development of three main issues: (i) the dissipated energy associated with the coefficient of restitution that includes the balance of kinetic energy and the conservation of the linear momentum between the initial and final instant of contact; (ii) the stored elastic energy, representing part of initial kinetic energy, which is evaluated as the work done by the contact force developed during the contact process; (iii) the dissipated energy due to internal damping, which is evaluated by modeling the contact process as a single degree-of-freedom system to obtain a hysteresis damping factor. This factor takes into account the geometrical and material properties, as well as the kinematic characteristics of the contacting bodies. The proposed contact force model has the great merit that can be used for contact problems involving materials with low or moderate values of coefficient of restitution. This contact force model is suitable to be included into the equations of motion of a multibody system and contributes to their stable numerical resolution. Two demonstrative examples of application are used to provide the results that support the analysis and discussion of procedures and methodologies adopted in this work.

scholarly journals Dynamics of Multibody Systems With Spherical Clearance Joints

2006 ◽  
Vol 1 (3) ◽  
pp. 240-247 ◽  
Author(s):  
P. Flores ◽  
J. Ambrósio ◽  
J. C. P. Claro ◽  
H. M. Lankarani
Keyword(s):  
Contact Force ◽  
Multibody Systems ◽  
Contact Forces ◽  
Force Model ◽  
Clearance Joints ◽  
Continuous Contact ◽  
Clearance Joint ◽  
Contact Force Model ◽  
Dynamics Of Multibody Systems ◽  
The Impact

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, with 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, with 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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