• Structural Engineering and Mechanics
• /
• 제82권2호
• /
• pp.205-224
• /
• 2022

This paper presents a refined finite element formulation for nonlinear static and dynamic analysis of sliding cable structures, overcoming the limitation of the existing approaches that neglect or approximate the friction, pulley dimension, temperature and geometric nonlinearity. A new family of elements with the same framework is proposed, consisting of the cable-pulley (CP) elements considering sliding friction, and the non-sliding cable-pulley (NSCP) elements considering static friction. Thereafter, the complete procedure of static and dynamic analysis using the proposed elements is developed, with the capability of accurately dealing with the friction at each pulley. Several examples are utilized to verify the validity and accuracy of the proposed elements and analysis strategy, and investigate the frictional, thermal and pulley-dimension effects as well. The numerical examples show that the results obtained in this work are in good accordance with the existing works when using the same approximations of friction, pulley dimension and temperature. By avoiding the approximations, the proposed formulation can be effectively adopted in predicting the more precise nonlinear responses of sliding cable structures.

• 동력기계공학회지
• /
• 제9권2호
• /
• pp.57-64
• /
• 2005

This paper is the study on dry sliding wear behavior of carbon fiber reinforced epoxy matrix composites against lay-up orientation. Tests were investigated on the effect of the lay-up orientation, fiber sliding direction, load and sliding velocity when circumstance keep continuously at $21^{\circ}C$, 60%RH. Pin-on-disk dry sliding wear tests for each experimental condition were carried out with a carbon fiber reinforced plastic pin on stainless steel disk in order to search the friction and wear characteristics. The wear rates and friction coefficients against the stainless steel counterpart were experimentally determined and the wear mechanisms were microscopically observed. The effect on friction and wear behavior are observed differently, according to various conditions. When sliding took place against counterpart, the highest wear resistance and the lowest friction coefficient were observed in the $[0]_{24s}$ lay-up orientation at anti-parallel direction.

• KSTLE International Journal
• /
• 제6권2호
• /
• pp.51-57
• /
• 2005

Surface texturing of tribological applications is an attractive technology of engineered surface. Therefore, reduction of friction is considered to be necessary for improved efficiency of machines. The current study investigated the potential of textured micro-scale grooves on bearing steel flat mated with pin-on-disk. We discuss reducing friction due to the influence of sliding direction at surface pattern. We can indicate lubrication mechanism as a Stribeck curve, which has a relationship between the friction coefficient and a dimensionless parameter for the lubrication condition. It was found that the friction coefficient was changed by the surface pattern and sliding direction, even when surface pattern was the same. It was thus verified that micro-scale grooves could affect the friction reduction considerably under mixed and hydrodynamic lubrication conditions. The lubrication regime influences the friction coefficient induced by the sliding direction of groove pattern. The friction coefficient depends on a combination of resistance force and hydrodynamic.

• Journal of information and communication convergence engineering
• /
• 제7권2호
• /
• pp.125-130
• /
• 2009

A robust friction compensation scheme is proposed in this paper. The recurrent fuzzy neural network and friction parameter observer are developed with sliding mode based controller in order to obtain precise position tracking performance. For a servo system with incomplete identified friction parameters, a proposed control scheme provides a satisfactory result via some experiment.

• 열처리공학회지
• /
• 제11권3호
• /
• pp.159-167
• /
• 1998

In this study, friction-wear test was carried out on the carburized layer depth of a mechanical structure steel SNCM carburized with RX and LPG for 7hrs at $930^{\circ}C$ and also the wear properties of wear loss, wear rate, coefficient of friction, friction force and friction temperature were investigated. The wear properties for carburized layer of SNCM were tested on dry condition at the room temperature by the thrust load of 49~245N range at sliding speed of 0.2m/sec and the sliding speed of 0.2~1.0m/sec range at thrust load of 98N. Wear loss on the depth of carburizing layer was increased with increasing of thrust load and sliding speed, and with decreasing of hardness. The condition of worn surfaces were showed mild wear at less than the thrust load of 98N and sliding speed of 0.6m/sec but were showed severe wear at more than 98N and 0.6m/sec. The friction load and temperature were increased with increasing of thrust load but with increasing sliding speed was appeared minimum at 0.6m/sec. With increasing thrust load the wear rate was increased and the coefficient of friction was decreased, but with increasing sliding speed the wear rate and the coefficient of friction were decreased in 0.2~0.6m/sec and increased in 0.6~1.0m/sec, therefore 0.6m/sec in this testing is a transition velocity.

• Tribology and Lubricants
• /
• 제25권4호
• /
• pp.243-249
• /
• 2009

A magnetic clutch consists of pulley and disk. It delivers and isolates the power needed for the operation of the compressor used in automotive air conditioning system. To improve the performance, efficiency and durability of automotive air conditioning system, appropriate design of pulley, disk and system working parameters(the magnitude of magnetic force, and so on) is necessary. For that goal, it is required to understand the friction characteristics of magnetic clutch for the initial operating time. In this study, friction tests were carried out in order to investigate the effect of sliding velocity on the friction characteristics of magnetic clutch using pin-on-disk type friction and wear tester. For experiments, pulley and disk used in real automotive air conditioning system were considered. Friction experiments were conducted under various sliding velocities, and coefficients of kinetic friction were obtained. Under the experimental conditions considered in this study, the coefficients of kinetic friction increased with the increase of test number(sliding distance) and decreased with the increase of sliding velocity.

• 한국윤활학회:학술대회논문집
• /
• 한국윤활학회 2002년도 proceedings of the second asia international conference on tribology
• /
• pp.189-190
• /
• 2002

Rolling-sliding friction was investigated for three SBR (styrene-butadiene rubber) specimens including silica-filled, HAF carbon black-filled, and SAF carbon black-filled SBR. When a rubber wheel was rolled against a glass disk, the coefficient of friction varied with the slip ratios. The coefficient of friction for the silica-tilled SBR showed the highest value of the rubber specimens examined under various slip ratios. The contact areas of silica-filled SBR were larger than those of the carbon black-filled SBRs, as indicated the modulus of the silica-filled SBR showing the lowest value. The contact area during rolling-sliding friction was always smaller than those during the static contact. The friction force at the unit contact area for the silica-filled SBR under braking and driving was higher than those of carbon black-filled SBRs.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 2000년도 제15차 학술회의논문집
• /
• pp.261-261
• /
• 2000

This paper analyzes the characteristics of pre-sliding friction of an X-Y table of CNC machining center at velocity reversal, and presents a simple and effective method of friction compensation based on this characteristics. At velocity reversal, a large position tracking error occurs because of the discontinuous change of friction. The relationship between the occurrence time of maximum position tracking error and the acceleration at zero velocity is analyzed by using the spring-like friction model. Furthermore, the experimental observation verifies this relation. From this, the state transition tine from pre-sliding regime into sliding regime can be predicted. Using the predicted transition time, the friction can be effectively compensated and table experimental results show its effectiveness.

• 한국소음진동공학회논문집
• /
• 제23권7호
• /
• pp.640-644
• /
• 2013

The present study provides the characteristics of friction noise under reciprocating sliding. The friction contact is generated between the aluminum plate and plastic, which results in friction noise. The experimental results reveal that the friction noise under reciprocating sliding can be produced as the friction coefficient increases. It is also shown that the vibration modes of the pin with dominant deflection in the sliding direction is participated on the friction noise.

• Tribology and Lubricants
• /
• 제16권1호
• /
• pp.1-8
• /
• 2000

Friction and wear tests have been performed on nylon, acetal resin, and PTFE (polytetrafluoroethylene), in reciprocating dry sliding conditions against steel discs. According to the results, acetal resin showed the lowest wear rates and PTFE exhibited the lowest friction coefficient. The prominent wear mechanisms found were adhesion and abrasion.