Drift Turning of Lateral Guided Vehicle With Sensor Steering Mechanism: Variable Kinetic Friction Model

2005 ◽  
Author(s):  
Yoshihiro Takita ◽  
Hisashi Date
Keyword(s):  
Friction Force ◽  
Coulomb Friction ◽  
High Speed ◽  
Static Friction ◽  
Friction Model ◽  
Tire Model ◽  
Kinetic Friction ◽  
Steering Mechanism ◽  
Three Stages ◽  
Coulomb Friction Model

In a previous paper, the simulated loci of high-speed cornering did not correspond with experimentally obtained results because the tire model used only the sticking in the Coulomb friction model. If the centrifugal force becomes larger than the cornering force of the tires, then the vehicle does not maintain the desired course. The cornering force is affected by the sticking or slipping condition of the tires. In order to simulate the high-speed cornering trajectory, the present paper assumes three stages of friction: low kinetic friction force at the beginning of slipping, the period of kinetic friction force, and the return to the static friction condition at small slip angles. In addition to the Rear motor Rear drive (RR) type vehicle, the Front motor Front drive (FF) type vehicle with a Sensor Steering Mechanism (SSM) and a 4-wheel steering mechanism is developed. In the experiments of present paper, both of these robots are run on an oval course at high speed. Numerical simulation and experimental results indicate effective prediction by the friction model.

Studies of Stick-Slip Friction, Presliding Displacement, and Hunting

2000 ◽  
Vol 124 (1) ◽  
pp. 111-117 ◽  
Author(s):  
Ruh-Hua Wu ◽  
Pi-Cheng Tung
Keyword(s):  
Coulomb Friction ◽  
High Speed ◽  
Experimental Studies ◽  
Friction Model ◽  
Smooth Transition ◽  
Stick Slip ◽  
Modified Model ◽  
Cyclic Motion ◽  
Coulomb Friction Model ◽  
The Stability

This paper presents the studies of stick-slip friction, presliding displacement and its influence on hunting. Experimental studies reveal that presliding displacement could affect the stability of hunting. A modified Coulomb friction model integrating presliding displacement in the microsliding regime is proposed to demonstrate such effect. Finally, step responses obtained from experiments and from the modified model are compared. These comparisons yield the conclusion that the transition of friction between the sticking state and the sliding state is smooth and continuous, not abrupt. Such a smooth transition of friction is critical to the studies of systems performing high-speed cyclic motion.

Analysis, Design, and Modeling of a Rotary Vane Engine (RVE)

2004 ◽  
Vol 126 (4) ◽  
pp. 711-720 ◽  
Author(s):  
B. V. Librovich ◽  
A. F. Nowakowski
Keyword(s):  
Coulomb Friction ◽  
Simple Structure ◽  
Dynamical Behavior ◽  
Friction Model ◽  
Reciprocating Engine ◽  
Torque Transmission ◽  
Analysis Design ◽  
Work Units ◽  
Coulomb Friction Model ◽  
Moving Parts

This paper introduces a mathematical model to analyze the dynamic behavior of a novel rotary vane engine (RVE). The RVE can be considered to have a number of advantages when compared to a majority of other reciprocating engine types. The advantages are found in the simple structure and the small number of moving parts. In this paper the geometrical structure and dynamical behavior of engines with a different number of work units is considered in detail. This has been examined through a study of torque transmission with a particular reference to how this is affected by the noncircular geometry of gear pitch curves. Using the Coulomb friction model, consideration has been given to the mechanical power loss due to friction in different parts of the engine, which must be taken into account. The study also proposes a possible method for balancing of asymmetric cogwheels. The analysis concludes that by using an appropriate design and arrangement of cogwheels and all moving parts, vibration can be attenuated due to impulsive gas torque.

Control for Robots With Braking Actuators in a Uniform Force Field

2015 ◽  
Author(s):  
Erlend Framstad ◽  
Mark D. Bedillion
Keyword(s):  
Force Field ◽  
Control Strategy ◽  
Coulomb Friction ◽  
Energy Equation ◽  
High Accuracy ◽  
Friction Model ◽  
Second Law ◽  
Inclined Plane ◽  
Position And Orientation ◽  
Coulomb Friction Model

This paper concerns the control strategy of a robot with controllable brakes placed in a uniform force field. Without loss of generality this force field is assumed to be gravity, and the robot to be an object resting on an inclined plane. The controller’s objective is then to use the brakes to lead the robot into a desired position and orientation. The system’s dynamics were derived from Newton’s second law with a Coulomb friction model. The controller was derived from geometric properties and the energy equation. The controller was then tested using Matlab and Simulink on the dynamics that were derived. The results of the simulation shows high accuracy even with some disturbances, and uncalibrated parameters.

scholarly journals Calculation and AFM Experimental Research on Slip Friction for Unlubricated Spherical Contact with Roughness Effect

Micromachines ◽  
2021 ◽  
Vol 12 (11) ◽  
pp. 1428
Author(s):  
Shengguang Zhu ◽  
Liyong Ni
Keyword(s):  
Friction Force ◽  
Sliding Friction ◽  
Static Friction ◽  
Friction Model ◽  
Rigid Sphere ◽  
Roughness Effect ◽  
Force Microscopy ◽  
Comparison Results ◽  
Experimental Values ◽  
Calculation Models

Previous research on friction calculation models has mainly focused on static friction, whereas sliding friction calculation models are rarely reported. In this paper, a novel sliding friction model for realizing a dry spherical flat contact with a roughness effect at the micro/nano scale is proposed. This model yields the sliding friction by the change in the periodic substrate potential, adopts the basic assumptions of the Greenwood–Williamson random contact model about asperities, and assumes that the contact area between a rigid sphere and a nominal rough flat satisfies the condition of interfacial friction. It subsequently employs a statistical method to determine the total sliding friction force, and finally, the feasibility of this model presented is verified by atomic force microscopy friction experiments. The comparison results show that the deviations of the sliding friction force and coefficient between the theoretical calculated values and the experimental values are in a relatively acceptable range for the samples with a small plasticity index (Ψ ≤ 1).

Asperity Spring Friction Model With Application to Belt-Drives

2003 ◽  
Author(s):  
Tamer M. Wasfy
Keyword(s):  
Finite Element ◽  
Coulomb Friction ◽  
Friction Model ◽  
Belt Drive ◽  
Finite Element Code ◽  
Time Step ◽  
Stick Slip ◽  
Normal Contact ◽  
Belt Drives ◽  
Coulomb Friction Model

An asperity spring friction model that uses a variable anchor point spring along with a velocity dependent force is presented. The model is incorporated in an explicit timeintegration finite element code. The friction model is used along with a penalty-based normal contact model to simulate the dynamic response of a two-pulley belt-drive system. It is shown that the present friction model accurately captures the stick-slip behavior between the belt and the pulleys using a much larger time-step than a pure velocity-dependent approximate Coulomb friction model.

scholarly journals Recent Developments and Trends in the Friction Testing for Conventional Sheet Metal Forming and Incremental Sheet Forming

Metals ◽  
2019 ◽  
Vol 10 (1) ◽  
pp. 47 ◽  
Author(s):  
Tomasz Trzepiecinski ◽  
Hirpa G. Lemu
Keyword(s):  
Sheet Metal ◽  
Sheet Metal Forming ◽  
Metal Forming ◽  
Coulomb Friction ◽  
Sheet Forming ◽  
Friction Model ◽  
Friction Resistance ◽  
Friction Testing ◽  
Coulomb Friction Model

Friction is the main phenomenon that has a huge influence on the flow behavior of deformed material in sheet metal forming operations. Sheet metal forming methods are one of the most popular processes of obtaining finished products, especially in aerospace, automobile, and defense industries. Methods of sheet forming are carried out at different temperatures. So, it requires tribological tests that suitably represent the contact phenomena related to the temperature. The knowledge of the friction properties of the sheet is required for the proper design of the conditions of manufacturing processes and tools. This paper summarizes the methods used to describe friction conditions in conventional sheet metal forming and incremental sheet forming that have been developed over a period of time. The following databases have been searched: WebofKowledge, Scopus, Baztool, Bielefield Academic Search Engine, DOAJ Directory of Open Access Journals, eLibrary.ru, FreeFullPdf, GoogleScholar, INGENTA, Polish Scientific Journals Database, ScienceDirect, Springer, WorldCat, WorldWideScience. The English language is selected as the main source of review. However, in a limited scope, databases in Polish and Russian languages are also used. Many methods of friction testing for tribological studies are selected and presented. Some of the methods are observed to have a huge potential in characterizing frictional resistance. The application of these methods and main results have also been provided. Parameters affecting the frictional phenomena and the role of friction have also been explained. The main disadvantages and limitations of the methods of modeling the friction phenomena in specific areas of material to be formed have been discussed. The main findings are as follows—The tribological tests can be classified into direct and indirect measurement tests of the coefficient of friction (COF). In indirect methods of determination, the COF is determined based on measuring other physical quantities. The disadvantage of this type of methods is that they allow the determination of the average COF values, but they do not allow measuring and determining the real friction resistance. In metal forming operations, there exist high local pressures that intensify the effects of adhesion and plowing in the friction resistance. In such conditions, due to the plastic deformation of the material tested, the usage of the formula for the determination of the COF based on the Coulomb friction model is limited. The applicability of the Coulomb friction model to determine the COF is also very limited in the description of contact phenomena in hot SMF due to the high shear of adhesion in total contact resistance.

Modelling of the Steel Pushing V-Belt Continuously Variable Transmission

1994 ◽  
Vol 208 (1) ◽  
pp. 13-27 ◽  
Author(s):  
J D Micklem ◽  
D K Longmore ◽  
C R Burrows
Keyword(s):  
Mathematical Model ◽  
Coulomb Friction ◽  
Continuously Variable Transmission ◽  
Friction Model ◽  
Full Potential ◽  
Shear Connection ◽  
System A ◽  
Variable Transmission ◽  
Coulomb Friction Model ◽  
Good Agreement

The steel pushing V-belt continuously variable transmission (CVT) is now commercially available in the automobiles of a number of manufacturers but to date it has not led to a significant reduction in fuel consumption. To develop its full potential it is necessary to have a good mathematical model of the system. A number of models have been described in recent years but all make use of a Coulomb friction model for the shear connection between the belt and the pulleys. This paper proposes a friction model based on elastohydrodynamic theory. It is shown that there is good agreement between measured and calculated slip values for the transmission which justifies use of the model.

scholarly journals Constitutive equation of friction based on the subloading-surface concept

2016 ◽  
Vol 472 (2191) ◽  
pp. 20160212 ◽  
Author(s):  
Koichi Hashiguchi ◽  
Masami Ueno ◽  
Takuya Kuwayama ◽  
Noriyuki Suzuki ◽  
Shigeru Yonemura ◽  
...  
Keyword(s):  
Rate Sensitivity ◽  
Steel Specimen ◽  
Static Friction ◽  
Friction Model ◽  
Smooth Transition ◽  
Kinetic Friction ◽  
Sliding Velocity ◽  
Friction Resistance ◽  
Negative Rate ◽  
Positive Rate

The subloading-friction model is capable of describing static friction, the smooth transition from static to kinetic friction and the recovery to static friction after sliding stops or sliding velocity decreases. This causes a negative rate sensitivity (i.e. a decrease in friction resistance with increasing sliding velocity). A generalized subloading-friction model is formulated in this article by incorporating the concept of overstress for viscoplastic sliding velocity into the subloading-friction model to describe not only negative rate sensitivity but also positive rate sensitivity (i.e. an increase in friction resistance with increasing sliding velocity) at a general sliding velocity ranging from quasi-static to impact sliding. The validity of the model is verified by numerical experiments and comparisons with test data obtained from friction tests using a lubricated steel specimen.

Experimental and Numerical Investigations on Frictional Behaviour under Consideration of Varying Tribological Conditions

2014 ◽  
Vol 966-967 ◽  
pp. 270-278 ◽  
Author(s):  
Marion Merklein ◽  
Fabian Zöller ◽  
Vera Sturm
Keyword(s):  
Coulomb Friction ◽  
Fe Simulation ◽  
Friction Model ◽  
Body Parts ◽  
Numerical Investigations ◽  
Drawing Test ◽  
Strip Drawing ◽  
Complex Test ◽  
Coulomb Friction Model ◽  
Frictional Behaviour

In present time the FE-simulation of body parts in sheet metal drawing processes has to be continuously improved to increase the prediction accuracy. The objective of this paper is to describe a methodology to improve the simulation by mapping the complex tribological conditions of the process in the simulation. This methodology focuses on the dependency of influencing parameters on the friction coefficient. The influence respectively the dependency of these factors has been investigated, both in an experiment of a plane strip drawing test and in a FE-simulation of this test. With the sensitivity analysis in the numerical simulation it is possible to compare the implemented Coulomb-friction-model against the experimental results. The results of the experimental and numerical investigation show the need of further investigations on a more geometrical complex test to prove if it is possible to transfer the knowledge and dependencies that has been found in the experiment with the strip drawing test to a more geometrical complex test.

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