Design and Analysis of a Lower Limb Rehabilitation Robot with Movement in Three-Dimensional Space

This study proposes a solution to the shortage of rehabilitation physicians in China and the limited capabilities of most lower limb rehabilitation robots in addressing both sagittal and coronal rehabilitation. Specifically, a new lower limb rehabilitation robot based on a parallel structure was developed to facilitate humans’ lower limb movements in three-dimensional space through a terminal pedal. This study encompasses four aspects of content: (1) simplifying the human lower limb into a skeletal linkage mechanism to determine the maximum range of movement in a human’ sitting position and obtain the expression of lower limb kinematic equations; (2) mechanical structure design of the lower limb rehabilitation robot; (3) conducting kinematics analysis of the proposed parallel mechanism for the rehabilitation training module and obtaining the Jacobian matrix to compute the distribution of condition numbers under known parameters; and (4) conducting trajectory planning and simulation of the proposed mechanism.