Numerical study of the effect of roller profile and ring skew on roller raceways contact pressure in cylindrical roller bearing

Bearing designs - Tapered roller bearing units

Vibroacoustic study of circular cylindrical tubes in roller coaster rails

Excessive noise generated by roller coasters during operation is a significant issue for amusement parks located near residential and business districts. Previous work showed that filling the rails with sand and pea gravel can provide noise reduction levels of up to 10 and 15 decibels. However, using damping materials may require additional support structures to accommodate the weight increase ...

Numerical Analysis of Grease Film Characteristics in Tapered Roller Bearing Subject to Shaft Deflection

The shaft deflection is one of critical factors that deteriorate the grease lubrication state inside the tapered roller bearings (TRBs). So, in this paper, on the premise of the TRB subjected to the combined loads and the shaft is deflected, the grease lubrication model at the TRB contacts was constructed, in which the interaction loads, linear and angular displacements of the bearing parts wer...

Study on Roller-Walker ï¿1⁄2 Energy Efficiency of Roller-Walk ï¿1⁄2

Roller-Walker is a leg-wheel hybrid mobile robot using a passive wheel equipped on the tip of each leg. The passive wheel can be transformed into sole mode by rotating ankle roll joint when Roller-Walker walks on rough terrain. This paper discusses energy efficiency of locomotion in wheeled mode. We define a leg trajectory to produce forward straight propulsion and discuss the relationships bet...

Descriptive study of female roller derby athletes' beliefs about risk factors for injury in roller derby

OBJECTIVES To examine skaters' beliefs about risk factors related to roller derby injuries. DESIGN Qualitative study based on semistructured focus group discussions with female roller derby skaters. METHODS Skaters with varying levels of experience and injury history were invited to participate in focus group discussions. Semistructured focus group discussions were based on the question 'Wh...