Effect of plantar pressure on stepping friction under cross-slope condition

There are various walking pavements in daily life. Slip accidents will happen if required friction for safe walking is greater than available friction between the foot and ground surface. Existing researches mostly focus on horizontal or slope pavements, whereas the cross-slope walkways are less. A self-developed gait friction test platform was used to test friction, distribution of plantar pressure and spatiotemporal parameters of human walking under cross-slope condition. With the increase of cross-slope angles, the mediolateral friction increases (R-2 = 0.972, P < 0.001), the anterior-posterior friction shows no significant change (R-2 = 0.758, P = 0.017), the normal pressure decreases (R-2 = 0.915, P = 0.007), and the high foot is more prone to slip and fall than low foot. Therefore, plantar pressure distribution of both feet was shifted to left. The gait cycle was prolonged (P < 0.001), swing period of both feet decreased (P = 0.029) and support period increased (P = 0.015) with the increase of cross-slope angle.