Effect Of Floor Surface Morphology On Human Step Friction Mechanism

The body posture of the human body during walking is called gait.Normal gait has many characteristics such as stability,periodicity and coordination.In daily production and life,slip accidents caused by gait instability are frequent,causing huge economic losses and casualties to countries around the world,and are highly valued.During walking,the soles of the feet and the ground form a pair of friction pairs.The intermittent interaction between the feet and the ground is called stepping friction.Stepping friction has a relatively broad application background,such as medical,military,sports,and shoemaking fields.At present,stepping friction mainly studies the influence of single factors such as sole material,pavement material,and surface condition on the anti-skid performance,while the friction research and the mechanism of stepping friction under the condition of multi-factor coupling are scarce.This article mainly studies the step friction mechanism of the material surface morphology change on the slope road surface to human walking,and provides further technical support for the anti-skid strategy of human walking on inclined roads.This article uses a self-developed step friction test platform to collect experimental data.The step friction test platform uses a six-degree-of-freedom motion platform to simulate an inclined road surface,a biomechanical force platform to collect the three-dimensional force of the human body while walking,and a three-dimensional motion capture system.The walking posture of the human body was collected,and the plantar pressure distribution of the gait was collected by the plantar pressure plate,supplemented by Visual 3D to establish a human motion model under the simulation system.After data processing and theoretical analysis,the following conclusions were reached:When the human body is walking on a road with a low pitch and inclination angle,the floor surface morphology has a small effect on the human step friction.After increasing the angle,the lateral barrier pattern and the mechanically processed surface morphology have better anti-skid performance.The foot contact area of the brake also decreases with the increase of the angle,and the pressure increases with the gait change of shortening the step length,increasing the step frequency first and then decreasing it to improve walking safety.When the human body is walking on a roll road,the lateral force of the low-side foot is greater than that of the high-side foot,and the friction coefficient is greater than that of the high-side foot.The slip tendency is higher than that of the high-side foot.The high-side foot force value is more volatile and less stable than the low-side foot..The effect of floor surface morphology on human step friction is less than the tilt angle.The friction coefficient during the starting period is greater than the braking period,and the slip tendency is large.There is no significant change in gait before the angle increases to 20 °.At 20 °,the step length is significantly shortened,the step frequency is significantly reduced,and the support phase time is increased.The lateral friction force value and friction coefficient increase with the increase of the tilt angle,and the slip tendency increases with the increase of the angle.