Abstract
To evaluate the slip resistances between floors and shoes, we developed a cart-type friction measurement device to measure both the static and dynamic coefficients of friction (SCOF and DCOF, respectively). The device was designed considering factors such as portability, normal load and sliding velocity conditions comparable to those in actual walking scenarios, measurement of both the SCOF and DCOF simultaneously, and measurement with variation in the sliding velocity. The device, pushed by the experimenter, dragged shoes across the floor, and the traction force was measured using a load cell. The three-axis acceleration acting on the footwear was measured with an accelerometer. The traction force measured using the load cell was corrected by the inertia force on the shoes because variations in the sliding velocity of the footwear were unavoidable. The COF from the load cell, with correction for the acceleration and slope angle, was close to that from the force plate. This result validates the COF measurement method using the cart-type friction measurement device. Thereafter, the friction measurement device was used to evaluate the slip resistances between commercial available floor sheets and shoes with flat outsoles and safety shoes. For shoes with a flat outsole, two floors showed low slip resistances, and one showed high slip resistance. For safety shoes, all the floors showed low slip resistances.
