Ergonomic Evaluation of Winnowing of Grains with Manually Operated Mechanical Paddy Winnower
Winnowing is a post harvest agricultural activity in rice producing country like India. Winnowing is done to remove straw, chaff and dust to get clean whole grains for consumption as well as for better market quality work. In traditional method, bamboo winnowers are used for winnowing of paddy grains which is a very time consuming and a laborious process. To overcome the drudgery of farm women in this activity, a manually operated mechanical paddy winnower has been designed by Central Rice Research Institute, India. An experiment was undertaken for testing the suitability of the technology for the farm women. Physiological cost of farm women while winnowing with the mechanical winnower was assessed in terms of physiological, muscular and postural stress as compared to traditional method of winnowing with bamboo winnower. Thirty farm women without any health problems actively involved in winnowing of grains were selected for the field experiment. Physical fitness was assessed using step stool Ergometer by recording the resting, working and recovery heart rate of the subjects. Heart rate for the experiment was recorded with Polar Heart Rate Monitor (Polar Sports Tester -PE4000). Rating of Perceived Exertion was calculated using Borgs 5-point rating scale while body map was used to identify pain in different body parts. Majority of the respondents belonged to Ectomorph group with slender body type. Physical fitness index (PFI) reveals that most of the respondents had ‘high average physical fitness. Average heart rate values while winnowing with mechanical winnower was lower (108.41 b/min) than the traditional method of winnowing (112.86 b/min). The resting heart rate value of farm women was 79.90 b/min. The average energy expenditure was observed to be slightly higher in traditional method (8.60 kJ/min). The farm women perceived less exertion (RPE value 3.1 in 5 point rating scale) in mechanical winnowing and the incidence of pain experienced by 45 percent respondents in shoulders, wrists and upper arm varied from ‘mild to ‘moderate, while severe pain in lower back, wrists and upper arms were common among nearly 65 percent respondents in traditional method. Postural analysis showed that the angle of deviations from normal curve with mechanical winnower was 4.64° as compared to the angle of deviation in the existing method of cleaning which was found to be 8.66°, this was due to the different postures adopted in traditional and improved method. The physiological workload was found to be ‘moderately heavy in both the methods of winnowing on the basis of heart rate and energy expenditures, however, the cleaning capacity of the mechanical winnower was three times higher and resulted in obtaining 90％ pure grain. The mechanical winnower is a gender specific technology with higher production efficiency and is a suitable alternative for large scale winnowing.
Ruplekha Bora
Department of Family Resource Management Faculty of Home Science Assam Agricultural University Jorhat – 785013, Assam, India
国际会议
17th World Congress on Ergonomics(第十七届国际人类工效学大会)
北京
英文
1-5
2009-08-09（万方平台首次上网日期，不代表论文的发表时间）