Effect of Step Length and Walking Speed on Traction Coefficient and Slip between Shoe Sole and Walkway

Abstract

The effect of gait parameters such as step length and walking speed on the traction coefficient and the slip between a shoe sole and a walkway was clarified experimentally, and desirable gait to reduce the chance of slipping was also suggested. The maximum peak value of traction coefficient obtained at heel-strike period |Fh/Fn|h and that at toe-off period |Fh/Fn|t increased with an increase of step length irrespective of subjects when walking on dry walkway. Meanwhile, |Fh/Fn|h or |Fh/Fn|t slightly decreased or took almost constant value with respect to walking speed. Based on the results of gait experiments on glycerin-lubricated walkway, it was clarified that a walk with a shorter step length and a higher walking speed was effective for prevention of slip irrespective of subjects, and such a gait provided a shorter slip distance. The reason why the smaller maximum peak values of traction coefficient can be obtained in case of walking with a shorter step length and a higher walking speed was discussed based on the kinematic analysis using the body center of mass (COM) and center of pressure of shoe sole (COP).