Development and evaluation of a novel overground robotic walker for pelvic motion support

Restriction of pelvic lateral and rotation motions caused by robotic devices can hinder successful gait rehabilitation. To tackle this issue, this paper presents a novel pelvic motion supported over-ground robotic walker developed for gait training. This device consists of an omni-directional mobile platform, a pelvic and trunk motion support brace unit, and an intuitive human-machine interface with force/torque sensor. With this proposed device, over-ground walking with 6 degrees of freedom (DoFs) pelvic motion facilitation was achieved in an intuitive and natural way. Preliminary gait experiments were carried out on three conditions of free walking, walking with and without pelvic lateral and rotational motions in order to evaluate the feasibility of the walker. The results showed that gait with pelvic motion facilitation strongly resembled free over-ground walking without alteration of the normal gait dynamics, while gait with pelvic restriction led to gait performances with reduction in the range of motion of lower limb. The findings of this research revealed that the pelvic motion facilitation with developed walker can provide better functional outcomes for gait rehabilitation.