Friction Measurement: Methods and Applications
ABSTRACT Friction measurement has been widely used as an assessment of slipperiness at the shoe-floor interface. However, controversies around friction measurements remain. The purpose of this chapter is to summarize our understanding about friction measurement with mechanical measurement devices related to slipperiness assessment of the interface between shoe and floor. Commonly used devices for slipperiness measurement are summarized. Static friction measurement, using the traditional drag-type device, is only suitable for dry and clean surfaces due to its limitation in properly reflecting lubrication at the measurement interface. Dynamic and impact friction methods are needed to properly estimate the potential risk on contaminated surfaces. Friction assessment using the mechanical measurement devices described herein appears generally valid and reliable. However, the validity of most devices could be improved by bringing them within the range of human slipping conditions to compare the results with the required coefficient of friction measured in biomechanical studies. Future studies should focus on understanding the tribological phenomena at the shoe-floor interface. For portable devices, it is important to improve their tribo-fidelity.
KEY WORDS: field based, laboratory based, slipperiness, slipmeter, tribometer.