KINEMATIC MODELING OF 4-POINT WALKING PATTERNS IN PARAPLEGIC SUBJECTS

We present a kinematic model of a paraplegic subject walking with crut ches where the subject with the crutches is modeled as a parallel kine matic structure. The model is employed to investigate if certain quadr upedal gait patterns can be implemented with functional electrical sti mulation, The study is motivated by the fact that the existing crutch- assisted gait realized by the electrical stimulation is slow and energ y inefficient, Gait patterns that would improve the walking are identi fied, The main characteristic of the patterns is that some of their st ates are not statically stable. During such states, the subject is sup ported by only a leg and a crutch, It is demonstrated that if the forw ard motion is provided by the stimulation of the plantar flexors the t rajectory of the renter of the body can closely follow the trajectory that is observed during walking of healthy subjects. We argue that the resulting gait is smooth and energy efficient, in addition, the unsta ble states make the walking faster.