TO SLIP OR NOT TO SLIP: A COMPARISON OF MATCHED SLIP AND NON-SLIP TRIALS UNDER SIMILAR CONDITIONS

摘要

This paper evaluates the kinematics and kinetics during early stance phase for matched trials of slips and non-slips that occurred under the same experimental conditions. Data were collected as part of a larger study where participants walked over several floor surfaces presented with and without contaminant, during a protocol designed to elicit a wide range of small slip distances. A motion analysis system tracked displacement of two heel-mounted markers and a forceplate provided ground reaction force measurements. Of the 867 trials collected, 47 instances occurred where two replications were performed by the same participant under the same conditions yet produced disparate outcomes, non-slips and slips. Analyses were performed to compare and contrast the kinematic and kinetic features that were associated with the different outcomes produced during the matched trials. ANOVA found no significant differences between the non-slip and slip trial for heel velocity, foot angle or utilized coefficient of friction (UCOF) at or about heel strike. However, significant differences in heel velocity, and UCOF were observed at greater than 25 ms post-heel strike and around the time of foot flat.