Abstract
Low back pain (LBP) is one of severe modern diseases due to the overload onto lumbar. Populations of 70% in the world suffer from LBP. The purpose of this study is to propose and develop the HAL for lumbar support in order to reduce lumbar load, and to verify the effect of the HAL on lumbar load reduction through an experiment at the task lifting a heavy load. Compressive force of lumbosacral disk and muscle strength of erector spinae can be represented as the function of lumbar moment. We proposed and developed the HAL for lumbar support in order to reduce the lumbar load. The HAL fixes movement of lumbar vertebrae and trunk flexion/extension motion is alternated to hip flexion/extension movement. The HAL reduces moment by supporting hip flexion/extension movement. In the experiment at the task lifting the heavy load, seven subjects lift the heavy load of 10 [kg] by using Stoop Lifting, first unsupported, then supported by the HAL. After the experiment, we executed three questionnaires as subjective assessment. From measurement results, it was confirmed that the HAL reduces the lumbar load corresponding to trunk flexion and dynamic motion. Results of subjective assessment showed that they could lift the heavy load easily. We proposed and developed the HAL for lumbar support in order to reduce the lumbar load, and verified the effect of the HAL on lumbar load reduction.
