A basic examination of lumbar burden evaluation based on elastic beam theory

Abstract

In industry, establishing methods to estimate lumbar burden is required for the safety validation of assist devices aiming at reducing the risk of low back pain in manual lifting tasks. However, estimating lumbar burden is difficult even when without using the devices. This paper proposes a method to estimate lumbar moment, one of the components of the burden, with modeling lumbar spine as an elastic beam. The modeling enables to estimate the moment without using body parameters, e.g. center of mass in link segmented models, which can affect the accuracy. Measurement experiment was conducted for estimating the moment with the proposed method under the movement of subjects’ leaning forward, backward with and without handling loads. The results indicated that lumbar moments were able to be estimated with the proposed method in their maximum bending posture, though accuracy enhancement were needed as a part of future work.