RAMANA, CPRABHAKARA RAO, T2019-05-212019-05-212018http://krishikosh.egranth.ac.in/handle/1/5810104103D5749India is the world’s largest producer, consumer and exporter of chilli. Chillies are cultivated mainly in tropical and sub-tropical countries like India, Japan, Mexico, Turkey, United states of America and African countries. Chilli is believed to have been introduced to India by Portuguese explorers at Goa in 17th century. The fruit of chilli plants have a variety of names depending on place and type. It is commonly called chilli pepper, red or green pepper, or sweet pepper in Britain, and typically just capsicum in Australian and Indian English. In Indian subcontinent, chillies are produced throughout the year. Two crops are produced in kharif and Rabi seasons in the country. Chilli grown best at 20–30°C temperatures, growth and yields suffer when temperatures exceed 30°C or drops below 15°C for extended periods. Now-a-days, cost of cultivation of chilli is increased day by day due to indiscriminate use of inputs like seeds, fertilizers and pesticides and also scarcity of labour. The major harvest season is between December-March with supply reaching peak levels in February-April. Planting is held mainly during August-October. Chilli cultivation needs more number of labourers for harvesting apart from the usual field operations such as sowing, weeding, pesticide applications, etc. as compared to other field crops. It is harvested (picking) 2 to 4 times and these harvestings are within a short span of time to get the quality produce, otherwise market price of chilli will be reduced. High cost and dearth of labour for hand harvest has resulted in increased chilli production cost declining even as consumption grows. Mechanization is only the way to reduce the cost of harvest and there by cost of production to make farmer comfortable with cost of harvest. The experimental set up was designed with two counter rotating double helical rollers of each length 200 cm and overall diameter 14 cm. The base frame was developed with the height of 100 cm, width of 85 cm and length of 160 cm to house the double helical rollers inside of the base frame. The rollers were fixed in the base frame inclined to the horizontal. The electrical motor was used as a prime mover to operate the double helical rollers at required speed for harvesting of ripens chilli pods. The experimental set up was tested to optimize the design parameters to get the maximum harvesting efficiency.The experimental unit of chilli harvester was fabricated to accommodate four different gaps between two rollers and four rotational speeds of counter rotating double helical rollers. The pulleys were changed on the double helical roller to get the four numbers of speeds like 289 rpm, 393 rpm, 484 rpm and 658 rpm by keeping constant pulley on power source. The four numbers of gaps were provided between the two rollers as 31cm, 32cm, 33cm and 340cm. The chilli harvester efficiency was calculated and varied from 29% to 31%. The harvesting efficiency of experimental set up was not in the acceptable range. The experimental set up was tested in all possible operating parameter combinations. The computed harvesting efficiency of machine observed at rollers speed of 289 rpm and rollers having gap of 320 mm was 9.41% at 2.0 km. h-1 forward speed. Likewise efficiency of machine at 330 mm gap of rollers was 9.97%, 14.00% efficiency was got at 340 mm space between rollers and 13.88% machine efficiency was observed at 350 mm gap between rollers with same 289 rpm of rollers speed with 2.0 km. h-1 forward speed. The roller speed was changed to 393 rpm and the computed resultant efficiencies of machine were 15.65%, 21.04%, 42.16% and 43.78% at rollers gap 320, 330, 340 and 350 mm respectively. The machine was run at 2.0 km. h-1 forward speed 481 rpm rollers speed with 320, 330, 340 and 350 mm space between rollers and computed efficiencies were 15.50%, 46.09%, 73.21% and 64.95% respectively. The efficiencies of machine at 658 rpm rollers speed with variable gaps between rollers 320, 330, 340 and 350 mm were 15.81%, 65.52%, 73.75% and 67.02%, respectively at same forward speed 2.0 km. h-1. In the similar way the machine was tested at 3.5 km. h-1 forward speed with variable gaps between rollers 320, 330, 340 and 350 mm at variable roller speeds 289, 393, 481 and 658 rpm respectively. The maximumefficiency 59.52% at rollers speed 658 rpm with gap 340 mm and minimum efficiency was observed 7.04% at 289 rpm rollers speed with gap between rollers 320 mm. The maximum mechanical damage of the harvested crop was 3.6%. The experimental set up was modified with regards power supply to double helical rollers, rotational speed and gap between the two rollers. The prototype ripened chilli harvester was fabricated with optimized design parameters and hitched to the high clearance tractor with help of two linkages. The power was transmitted to run the double helical rollers from the high clearance tractor PTO. The machine was evaluated in the farmers fields at Murikipadu village in Guntur district. The prototype harvester was operated with the optimized combinations of rollers speed and gap between two rollers like S1G1, S1G2, S1G3, S1G4, S2G1, S2G2, S2G3, S2G4, S3G1, S3G2, S3G3, S3G4, S4G1, S4G2, S4G3 and S4G4. The prototype chilli harvester was evaluated at each combination of rollers and the harvesting efficiency of prototype ripen chilli harvester was 72.08% at the speed 2.0 km. h-1 and roller gap of 340 mm. Thecalculated efficiencies were compared with existing practice of harvesting in manual harvesting. The labour required for harvesting of ripened chilli varied from 350 to 400 man.days per acreand approximate cost incurred for pickings was Rs.93750/- per acre whereas mechanical harvesting with developed machine was Rs.1567 per picking and for two pickings it is Rs.3134 per acre (Rs.7835/- per hectare). More importantly the labour saving was 98% and 2904 man hours when compared to manual harvesting.en-USnullThesis