Effects of Footpad Slope, Movement Direction and Contact Part of Foot on Foot-based Interactions

Abstract

The feet cannot perform tasks as quickly and with as much dexterity as the hands. However, due to the heavy workload placed on the hands, there is potential for the feet to replace or assist the hands. In order to use the feet more effectively, this study aims to find ways to increase the speed and accuracy of directly touching a touchpad with the feet while in a seated position. The study investigates the effects of three factors: the slope of the touchpad, the direction of foot movement, and the touch area of the foot used. Regarding the direction of foot movement, the study found that the most effective direction for both accuracy and speed was at a 30-degree angle to the right when the front of the right foot was set at 0 degrees. The 0-degree and 60-degree angles showed similar efficiencies, but were lower than the 30-degree angle. The study also found that using the big toe as the touch area resulted in the best speed, accuracy, and subjective satisfaction. The index toe was the second-best option, while using the ball of the foot was the least accurate and slowest option. Lastly, using an slope angle of 15 degrees for the touchpad was found to increase work efficiency compared to using a 7-degree slope angle. These findings can serve as guidelines for designing foot interfaces.