Host: The Japan Society of Mechanical Engineers
Name : Dynamics and Design Conference 2019
Date : August 27, 2019 - August 30, 2019
We experimentally examined the effect of foot mounting position on walking speed in a planar passive walker with flat feet and ankle springs. First, in the compass-like passive walking model with pointed feet, we conducted a simulation to investigate the influence of the position of the mass center of the leg and the moment of inertia around the mass center of the leg on the walking speed. Next, we constructed a planar passive walker with flat feet and ankle springs and no knees. While designing the walker, we used the compass-like passive walking model with pointed feet to determine the position of the center of mass of the leg and the moment of inertia around the mass center of the leg at which the walking speed was maximum. The constructed passive walking machine has a leg length of 0.5 m, a foot length of 0.1 m, and a total mass of 5 kg. Changing the amount of foot attachment offset to 0, 0.025, and 0.05 m, we measured the step length and step time at multiple inclination angles of the slope, and then calculated the average walking speed from the data. The experimental results demonstrated a decrease in the walking speed as the offset amount increased. For instance, at the offset amount of 0 m and slope angle of 0.038 rad, the walking speed was 0.56 m/s. At the same slope angle, the walking speed decreased by 27 % when the offset amount was increased to 0.025 m. Furthermore, at 0.05 m offset amount, we could not find a stable walking position when the slope angle was smaller than 0.038 rad.
