Asymmetric three-link passive walker

Passive walkers are dynamically stable robots with a gait that resembles the human locomotion. These walkers can be studied to better understand the dynamic behavior of the human gait and design efficient active walkers and assistive devices. In this paper, we study the walking dynamics of a three-link passive walker with an asymmetrical structure where one leg has a knee while the other is knee-less. After finding a 2-periodic steady gait for the three-link walker with humanlike inertial parameters for both legs, the possibility of a gait with symmetrical step lengths is discussed where the half inter-leg angles at the beginning of every step are made equal by altering the physical parameters of the knee-less leg. We further study the gaits with symmetrical step lengths and show that by replacing one leg of a four-link symmetric walker with the knee-less leg of the three-link walker with the symmetrical half inter-leg angles, the dynamic behavior of the kneed leg remains unchanged. This approach can be adapted in the field of gait rehabilitation and prosthesis design to obtain a more symmetrical gait and preserve the motion of the healthy leg.