Engineering properties of finger and foxtail millet seeds for development of remote-operated millet planter

Abstract

Engineering properties of seeds constitute essential design parameters for the development and efficient operation of precision sowing equipment, particularly for small-seeded crops such as millets. The present study evaluated selected physical and frictional properties of finger millet (Eleusine coracana) and foxtail millet (Setaria italica) seeds with specific reference to the design of a remote-operated precision planter. The properties analyzed included principal dimensions (length, width and thickness), geometric mean diameter, bulk density, angle of repose, and coefficients of internal and external friction, all determined using standardized experimental procedures. Finger millet seeds recorded mean dimensional values of 1.70 mm (length), 1.45 mm (width) and 1.33 mm (thickness), whereas foxtail millet seeds exhibited corresponding values of 2.24 mm, 1.53 mm, and 1.23 mm. The bulk density was found to be 708.2 kg m⁻³ for finger millet and 724.07 kg m⁻³ for foxtail millet. The angle of repose ranged from 27.08° to 31.85°, indicating satisfactory flowability suitable for hopper-based seed handling and delivery systems. The engineering data generated from this study provide a scientific basis for the rational design and optimization of seed hoppers, metering mechanisms and delivery units, thereby enhancing the precision, reliability and operational efficiency of remote-operated millet planters.