Dynamic Pushing and Pulling and Implications for Slipping

Abstract

Eight male subjects performed pushing and pulling tasks on 2 level floor surfaces having good and reduced resistance to slipping. Using a four wheel industrial trolley, adapted so that the force required to move it could be varied by adding weights to boxes attached to either side, a psychophysical approach was used to determine maximum acceptable forces for each of 4 experimental conditions. Mean initial maximum acceptable forces were 439N (slip-resistant surface/pushing), 430N (slip-resistant surface/pulling), 453N (slippery surface/pushing), and 410N (slippery surface/pulling), with differences between conditions non-significant. Thus, for these subjects, maximum acceptable forces were independent of the floor surfaces used. This was despite significant differences (p<0.001) in ratings of perceived slipping.