Abstract
Cotton, an economically significant crop, incurs high input costs for Bt cotton seeds. Commonly used varieties like RCH 2, Ajeet 155, Ankur 3028, and Suraj exhibit variations in seed size and mass, influencing the design of seed metering plates in pneumatic planters. Typically, each variety requires a specific metering plate optimized for orifice size, vacuum pressure, and operation speed, increasing costs, time loss, and labor dependency. This study aims to design a single seed metering plate accommodating all varieties, optimizing easily adjustable parameters such as vacuum pressure and operational speed. Employing a central composite rotatable design (CCRD), experiments varied orifice diameter (2.5-3.5 mm), vacuum pressure (2.5-5.5 kPa), and speed (2.5-5.5 km/h). Variety-specific optimal values were determined by initial optimisation using the response surface method (RSM). An average orifice diameter of 3 mm was then targeted by a second optimisation stage, which found the corresponding forward speed (4.16-4.22 km/h) and vacuum pressure (3.74-4.11 kPa) for each variant. Cost involved in purchase of different metering plates and timeliness cost associated with changing metering plates is saved and simultaneously precision seed sowing is achieved.