Applying Ergonomic Techniques to Optimize Supply Chain Efficiency

Abstract

Manual material handling in industries often forces workers into awkward and repetitive postures, leading to musculoskeletal disorders (MSDs), fatigue, and productivity losses. These ergonomic risks directly impact supply chain performance by increasing cycle times, reducing throughput, and raising absenteeism. This thesis addresses these challenges by integrating ergonomic monitoring with supply chain optimization. A wearable ergonomic posture monitoring device was created to gather real-time joint angle information from the trunk, upper arm, lower arm, wrist, and neck. The device has inertial measurement sensors, a microcontroller, data logging, and a buzzer feedback system that warns workers when they are in dangerous positions. Validation against Kinovea motion analysis software demonstrated an average accuracy of approximately 97.4%, with a mean absolute error of 1.76°, thereby affirming its reliability for industrial use. The device, which used RULA as the assessment framework, showed that industrial tasks at baseline had high risk scores (average RULA 6–7), but that post-intervention with real-time feedback lowered the scores to medium risk levels (RULA 3–4). A lever-assisted CAD device was created in addition to monitoring to reduce the strain associated with handling heavy loads during conveyor-to-pallet transfers. To lessen lifting effort and trunk flexion, the CAD model incorporates a pivot lever mechanism and roller tray. According to time-motion analysis supported by the literature, this device could reduce the average cycle time per box transfer by approximately 35%, from 17.0 seconds to 11.1 seconds. Throughput is therefore anticipated to increase by approximately 17.2%, from 180.34 boxes per hour to 211.38 boxes per hour. The redesigned posture with the lever-assisted device lowers the RULA score from 7 to 3, confirming both safety and efficiency gains, according to additional validation from the CATIA V5 simulation. This study shows that ergonomics-based interventions have quantifiable supply chain benefits in addition to safeguarding worker health. Ergonomics becomes a strategic enabler of industrial efficiency and sustainability by decreasing posture risks, reducing cycle times, and increasing throughput. The results offer a reproducible framework for incorporating human-centered design into manufacturing and warehouse processes, balancing supply chain optimization with worker well-being.