Abstract: Two type of self-propelled power weeders used in the eggplant crop were evaluated with three subjects of different age group who were allowed to work at different day timings at different forward speeds and different depth of operations. The duration of work was kept of 120 minutes. The weeders were evaluated by recording the body temperature, blood pressure, pulse rate, heart rate, and body posture and finally based on average heart rate, the energy expenditure of the subject was considered as a criterion. During the ergonomic evaluation, 4 HP self propelled power weeder and 8.38 HP self propelled power weeder it was found that the body temperature of the operator rises in accordance to the rise in forward speed, duration of time, nature of work done and time of work. The highest rise in temperature was observed in the evening whereas nominal increase was in the morning time. Similar phenomenon was observed in blood pressure, heart rate and pulse rate. The change in the body posture was calculated in the net bending angle that was observed most when the speed of weeding operation was 4.8km/h in 8.38 HP self-propelled power weeder, which was 6.28˚. The 4.00 HP self-propelled power weeder showed a variation of 9.226 to 17.108kJ/min when the forward speed was increased from 1.2km/h to 2.4 km/h and 8.38HP self-propelled power weeder ranged from 6.614 kJ/min to 19.475kJ/min. It was observed in the operators that after the continuous work of 120 minutes the energy expenditure had a great hike from the normal condition. It is estimated that burning of one litre of oxygen results in energy consumption of 29.9 kJ.

Keywords: weeding operation, self-propelled, body temperature, blood pressure, pulse rate, heart rate, body posture

| DOI: 10.17148/IARJSET.2022.9485