Reducing Physical Load for Desk-Height Tasks by Supporting Kneeling Posture with a Lower Limb Exoskeleton

Performing manual tasks at desk height can cause musculoskeletal disorders, posing a significant burden on individuals worldwide. This study aims to propose an ergonomic solution by adopting a kneeling posture, which alleviates strain on the lower back. Additionally, it evaluates the effectiveness of an exoskeleton designed to support the lower limbs in maintaining this kneeling posture. A simple human model was created from motion capture data to simulate loads on the lower back in three postures: kneeling, sitting, and standing. The simulation findings suggest that a kneeling posture can reduce back strain when working at desk height. However, this posture may increase strain on the lower limbs. To address this issue, an exoskeleton designed to support the lower limbs in the kneeling posture is evaluated for its effectiveness in this study. This paper assesses the exoskeleton’s impact on static stability and muscle activity in the lower back. A comparison was also made between kneeling with the exoskeleton, standing, and sitting postures. Myoelectric sensors were used to monitor the muscle load on the lower back and lower extremities of six participants as they performed tasks in each posture. The results indicate reduced muscle activity, highlighting the potential effectiveness of using the kneeling posture with the exoskeleton for performing manual tasks at desk height.