Abstract
The HIT lower limb exoskeleton is presented for load-carrying augmentation of human being. The load-supporting stages during a gait cycle mainly include the single support phase and the double support phase. And the latter gradually disappears with the increase of the walking speed. In this paper, we focused on the human movement detection and exoskeleton control in the single support phase. The HIT lower limb exoskeleton is only actuated on the hip and knee. A dorsal man- machine interaction device is designed and installed between the human back and the exoskeleton to detect the interaction forces, including two-dimensional forces and one-dimensional torque on the sagittal plane. By the kinematic analysis, an equivalent kinematics model is establishment. Then all the control objectives are described in the new coordinate systems of the equivalent model. As an underactuated system, not all the dorsal interaction forces could be relieved. Based on the selected control inputs, a double feedback control strategy is designed for the supporting leg control.
