Abstract
This study developed a method to quantify required coefficient of friction (RCOF) during ladder climbing. This method was then used to assess the impact of ladder angle on slip risk. Just like in gait, we assert that slip risk during ladder climbing could be determined using RCOF. Subjects climbed a ladder positioned at three angles (90°, 82.75°, and 75.5°). Forces were measured using a force plate and then projected onto the orientation of the shoe-rung contact region to determine shear and normal forces. The maximum RCOF was determined from the force plate forces and shoe orientation with a set of criteria. The maximum RCOF for a ladder set at 90° and 82.75° was significantly larger than from the maximum RCOF for a ladder set at 75.5°. The maximum RCOF increased as the ladder became steeper, indicating climbers may be more susceptible to slipping while climbing a steeper ladder.