Comparison of ergonomic performance evaluation in mechanized and traditional date stripping processes

Al-Mabsili date postharvest processing is done by traditional ways in Oman, blended with traditional and cultural practices. This research aimed to mechanize the date stripping process, developed a prototype with multiple power options and compared ergonomic performance with traditional method. Three power sources were bicycle, exercise machine and electric motor. Ergonomic performance tests were based on standard Cornell discomfort evaluation techniques for whole-body, hands and seating posture. The changes of human physiological parameters, energy spent, and standard NIOSH lifting evaluation were also tested. The results showed increase in heartbeat, systolic and diastolic blood pressures, oxygen consumption and body temperature in all tests. The energy expenditure was highest in traditional method (14 kJ/kg), while bicycle and exercise machine had the higher energy expenditure rates (25.7 and 24.3 kJ/min). The Cornell whole-body postural discomfort was lowest in exercise machine and highest in traditional method. Neck and shoulders were the most affected areas in mechanical methods while hip, buttocks and lower back were most affected in traditional method. In Cornell hands discomfort evaluation, right hand was more affected than the left in all methods and first three fingers and the thumb were most affected. The Cornell seat comfort evaluation showed exercising machine with more comfort (66.7%), bicycle in average (51.9%) and traditional method in poor (9.3%) comfort levels. The average NIOSH lifting index was 0.54 a very satisfactory condition. The stripping was usually done manually and sitting on the ground, 5-10 min/bunch. Ninety percent preferred electric motor as power source followed by bicycle.