Affiliations: Department of Agricultural Engineering, North Eastern Regional Institute of Science and Technology (NERIST), Nirjuli, Arunachal Pradesh, India
Correspondence:
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Address for correspondence: Thaneswer Patel, Department of Agricultural Engineering, North Eastern Regional Institute of Science and Technology (NERIST), Nirjuli, Arunachal Pradesh, India. Tel.: +91 94362 28996 (M); Fax: +91 360 2257418; E-mail: [email protected].
Abstract: BACKGROUND: Manual orange harvesting is very laborious, time consuming and unsafe operation whereas neither mechanical harvesting nor mechanized hand harvesting is possible in north-east India due to its hilly terrains. The awkward postures and repetitive nature of work in orange harvesting, demands a comfortable and appropriate hand harvester for hilly region. OBJECTIVE: The purpose of this study was to develop a manual orange harvester for hilly regions considering the ergonomic parameters, and compare the performance with the existing models of the manual harvester. PARTICIPANTS: In this study twenty healthy experienced orchard workers (10 male and 10 female) participated who did not have any previous functional musculoskeletal disorders. METHODS: We developed a manual orange harvester by eliminating the problems associated with the existing harvesters. The developed model along with existing models was evaluated extensively in the field. During evaluations, heart rate of the subjects was measured and oxygen consumption was predicted to calculate the energy expenditure rate (EER) from the established relationship in the laboratory before the field experiments. Further, performance parameters of orange harvester i.e. plucking rate (PR), damaged quantity (DQ), plucking energy requirement (PER) and discomfort rating were also observed. RESULTS: The PR was 425, 300 and 287 pieces per hour for the developed model (DM), first existing model (EM1) and second existing model (EM2), respectively. The DM showed lower PER (2.14 kJ/piece) followed by EM2 (2.95 kJ/piece) and EM1 (4.02 kJ/piece) which is considered as overall performance as it includes energy per unit of plucking. Further, the body part discomfort score revealed that DM was more comfortable in use followed by EM2 and EM1. CONCLUSIONS: The performance of the DM was found better in terms of plucking rate, energy requirement and body part discomfort than the other existing models. Shoulders and neck are the most affected body parts where all subjects felt severe discomfort.
Keywords: Manual harvester, orange, heart rate, energy expenditure rate, discomfort
