Fatigue Evaluation in Manual Handling Using Surface EMG and Ergonomic Design of Trolley

Musculoskeletal disorder (MSD) is one of the major health problems that are related to physical labour especially in jobs requiring manual work and the muscle fatigue is considered to be closely related to the muscle-related disorders. In addition to the existing techniques for fatigue assessment, the present research focuses on the use of electromyography for analyzing the fatigue at the workplace. This method calculates the fatigue at the muscular level which helps in evaluating the exact risk for further analysis. Since the spine is the most affected part during manual handling, the present research focuses on the muscle activity of spine for comparison of the risks associated with manual handling as well as using the trolley. The lifting of scrap load obtained from stretch forming machine in an industry is analyzed and an ergonomically designed trolley is suggested for lifting and carrying. The main objective of this research is to design the optimum handle height of the trolley which induces lower compressive stresses on the spine. The experimental values obtained for muscle activity of spine is compared with the data obtained from motion analysis using biomechanical software using 3DSSPP. The percentage reduction of muscle fatigue analysis is compared with Revised NIOSH lifting equation. It infers that the use of trolley for material handling significantly reduced the fatigue than manual material handling.