P.K. Pranav

Impact of ergonomic intervention in manual orange harvester among the workers of hilly region in India

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.

Mechanical intervention for reducing dust concentration in traditional rice mills

A huge number of workers are employed in traditional rice mills where they are potentially exposed to dust. In this study a dust collection system was developed to capture the airborne dust in the rice mill. The feeding and sieving section of the mill was identified as major dust creating zone. The dust was captured by creating suitable air stream at feeding and sieving sections of the mill and collected in cyclone dust collector. The air stream was created by blower which was selected on the basis to get minimum air speed of 0.5 m/s in the working zones of workers. It was observed that the developed system is successfully collects the significant amount of dust and able to reduce the dust concentration up to 58%. Further, the respirable dust concentration reduced to below 5 mg/m3 throughout the mill which is within the recommended limit of dust exposure.

Computer Simulation for Haulage Performance of Power Tiller

The presence of a large number of marginal and small land holdings in India has rendered the power tiller to be the most suitable farm equipment for field operations, in view of its compact size, profitability and versatility, but the transport work which is also required to carry the farm produce is yet to be proved. Keeping these in mind, user friendly software was developed for predicting the haulage performance of power tiller to meet requirements in educational and research organizations. The developed software requires input parameters such as power tiller, trolley and operating conditions. The developed software was validated by conducting experiments with a 6.7 kW power tiller using a suitable trolley on tarmacadam road at various payloads and road slopes. The draft, slip, fuel consumption and speed were measured and other haulage performance parameters were calculated based on measured values to validate the developed software. The results simulated by software indicate lower draft and slip in the range of 1-23 and 2-9% with respect to the experimental data, however, higher transport productivity was in the range of 3-12%.