Dynamics of Impacts and Collisions of the Rolling Balls

To enhance transport safety and reliability of ropeway systems, it is essential to reduce the swing of the carriers that results from wind, etc. In the previous report [1], we provided a practical damping equipment using two rolling balls (hereinafter described as “two-ball rolling type damping equipment”) to reduce the swing of ropeway carriers. A linearized dynamic model is proposed. Then, on the basis of relevant parameters, the frequency response and time domain response of the system is studied and discussed. In this report, we will study relationship between theoretical best damping coefficient ratio and friction coefficient of two-ball system. Then we will provide the way to implement the desired damping for the two-ball system. We will then provide the detail on how to estimate the inherent damping within the two-ball system. In addition, we will show and discuss two balls behavior when this equipment works experimentally.

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Using fractal geometry to make rapid field measurements of riverbed topography at ecologically useful spatial scales

Marine and Freshwater Research ◽

10.1071/mf01222 ◽

2002 ◽

Vol 53 (6) ◽

pp. 999 ◽

Cited By ~ 7

Author(s):

B. J. Robson ◽

E. T. Chester ◽

L. A. Barmuta

Keyword(s):

Fractal Dimension ◽

Fractal Geometry ◽

Random Sampling ◽

Spatial Scales ◽

Field Measurements ◽

Habitat Types ◽

River Bed ◽

Bed Roughness ◽

Rolling Balls

A method is described for making rapid in situ field measurements of riverbed topography over spatial scales of ≅1–10 m. This method uses rolling balls to make quick, accurate measurements of river-bed roughness at several spatial scales. Random sampling and replication generate multiple estimates of the fractal dimension (d) that can be used to test for significant differences in the complexity of riverbed architecture between habitat types and spatial scales.

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Passive Balancing of Rotor Systems Using Pendulum Balancers

Journal of Vibration and Acoustics ◽

10.1115/1.2731401 ◽

2008 ◽

Vol 130 (4) ◽

Cited By ~ 13

Author(s):

Roland Horvath ◽

George T. Flowers ◽

Jerry Fausz

Keyword(s):

Simulation Model ◽

Dynamic Characteristics ◽

Recent Literature ◽

Experimental Studies ◽

Simulation Studies ◽

Additional Insight ◽

Rotor Systems ◽

Rolling Balls ◽

Insight Into

Passive balancing techniques have received a great deal of attention in recent literature, with much of this work focused on ball balancer systems. However, for certain applications, balancing systems that use pendulums rather than rolling balls may offer distinctly improved balancing precision. This investigation seeks to provide additional insight into the performance and expected behavior of such systems. A simulation model is developed for a pendulum balancer system with isotropic supports and analyzed in detail. The influence of shaft location and friction on balancing effectiveness is considered and evaluated. In this regard, the dynamic characteristics of a pendulum balancer system are analyzed and compared to a similar ball balancer system. The conclusions and observations from the analysis and simulation studies are demonstrated and tested in a series of experimental studies.

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The Development of gearless reducers with rolling balls

Journal of Mechanical Science and Technology ◽

10.1007/s12206-009-1155-0 ◽

2010 ◽

Vol 24 (1) ◽

pp. 189-195 ◽

Cited By ~ 12

Author(s):

Hidetsugu Terada

Keyword(s):

Rolling Balls

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On some generalization of the area theorem with applications to the problem of rolling balls

Regular and Chaotic Dynamics ◽

10.1134/s1560354712020086 ◽

2012 ◽

Vol 17 (2) ◽

pp. 199-217 ◽

Cited By ~ 8

Author(s):

Sergey A. Chaplygin

Keyword(s):

Area Theorem ◽

Rolling Balls

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Sticking of a Linear-Guideway Type Recirculating Ball Bearing

Journal of Tribology ◽

10.1115/1.4034961 ◽

2017 ◽

Vol 139 (3) ◽

Cited By ~ 4

Author(s):

Hiroyuki Ohta ◽

Genta Hanaoka ◽

Yusuke Ueki

Keyword(s):

Driving Force ◽

Ball Bearing ◽

Sliding Friction ◽

Stroke Length ◽

Rolling Moment ◽

Moving Body ◽

Moment Load ◽

Rolling Balls

In this paper, the driving force of a linear-guideway type recirculating ball bearing (linear bearing) is measured and explained as the first step toward an understanding of sticking, which is the significant increase in driving force required to move a linear bearing under back-and-forth operation with a short stroke length. First, the driving force required for operation of a test bearing (which is a linear-guideway type recirculating ball bearing with load balls) and acceleration of a moving body (which consists of a carriage of the test bearing, an arm, and weight) were measured. The measurements showed that the sticking occurred when the test bearing, under a relatively higher rolling moment load, was driven in an offset position for a certain period. Next, the driving force of a test bearing with alternating load balls and spacer balls was measured, and it was clear that the cause of the sticking was the sliding friction between rolling balls. Finally, the ball locations in the load zone of the test bearing with load balls were observed in operation, and the occurrence process of the sticking is explained.

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