本研究针对棒球投球中指尖-球体摩擦(finger-ball friction)对投掷动作的影响展开深入探究。研究人员通过应用水(低摩擦)和松香粉(高摩擦)模拟不同摩擦条件，采用运动捕捉技术分析8名半职业投手在投掷四缝线快速球时的上肢运动轨迹。研究发现低摩擦条件下投球 ...

The A 755Y... Series of ABEC 3 ball bearings are suitable for applications requiring low-friction movement. The bearings support axial and radial loads with minimal ...

Schaeffler’s standard deep groove ball bearings set the benchmark when it comes to relevant technical characteristics, such as minimising friction and noise. Reduced friction means, for example, lower ...

Print & Full Archive SubscriptionThis digital issue plus 12 new issues (in print, digital and tablet formats) plus archive access to 1845.$99.00 ...

If you enjoyed this article, I’d like to ask for your support. Scientific American has served as an advocate for science and industry for 180 years, and right now may be the most critical moment in ...