Knee-assistive robotic exoskeleton (KARE-1) using a conditionally singular mechanism for industrial field applications

Abstract

With the aging demographic of today's society, the need for robotic exoskeletons is expected to increase as they can compensate for declining physical strength in the physically impaired. In this study, an assistive robotic exoskeleton for the knee joint with fairly low energy consumption is proposed for industrial applications. The knee-assistive robotic exoskeleton (KARE-1) was designed to support a human body during production line tasks. The KARE-1 is based on a four-bar link mechanism with a rotary actuator and gas spring to accommodate a high power-to-weight ratio. By taking advantage of the utilized singular configuration of the four-bar linkage, this novel design is able to efficiently support the weight of the human body. The selected singular configuration allows this device to support the knee joint in the load-bearing stages of static sitting as well as during the motion between standing and sitting. The proposed device is further able to move freely along with the knee during walking movements. The proposed design was verified through a series of numerical simulations and through human subject testing at an industrial workplace.