Musculoskeletal Modelling And Simulation Of Oil Palm Fresh Fruit Bunch Harvesting

Abstract

This study aims to create and evaluate an upper extremity musculoskeletal model of the oil palm harvesting motion and assess the Musculoskeletal Disorder (MSD) risk of this activity. Tests were conducted on six harvesters at a Malaysia oil palm plantation. Six Inertial Measurement Units (IMU) and Surface Electromyography (sEMG) were used to collect kinematics of the back, shoulder and elbow joints and measure the muscle activations of longissimus, multifidus, biceps and triceps. A musculoskeletal model was constructed and simulated using the IMU data. The results were benchmarked against the commercial motion capture tool and sEMG. It was found that joint angle had the maximum coefficient of correlation (R) of 0.99 and minimum Root Mean Square Error of 1.84°, whereas muscle activation had the maximum R of 0.87 and minimum Mean Absolute Error of 0.10. This study showed that the longissimus was more actively used than multifidus, and the biceps was another primary muscle relied on during harvesting. The harvesters faced a higher risk of MSD while performing back flexion, back rotation, shoulder flexion and elbow flexion. Lastly, it demonstrated the feasibility of the musculoskeletal modelling and simulation to further investigate the upper extremity joints and muscles during harvesting.