Development of a sensor system for detection of missing seeds in a tractor-operated groundnut planter

To minimize the missing seeds in groundnut planting, an Infra Red (IR) technology based sensor system was developed for a tractor drawn 9- row groundnut planter. This system could detect the number of groundnut seeds falling through a seed tube and provides visual and audible indications of missing drop(s). Laboratory evaluation of the planter with sensor system indicated that the variations of actual number of seeds dropped and display reading varied from 4.97% to 6.72% when operating speed varied from 2.5 km.h⁻¹ to 3.5 km.h⁻¹. The seed rates were 118.53 kg.ha⁻¹ at 2.5 km.h⁻¹, 100.10 kg.ha⁻¹ at 3.0 km.h⁻¹ and 93.20 kg.ha⁻¹ at 3.5 km.h⁻¹ operating speed. Under field condition, the planter without sensor system had lowest (22.60%) missing seeds at speed of 2.5 km.h⁻¹, and highest (32.85%) missing seeds at higher speed of 3.5 km.h⁻¹; while the planter with sensor system had 5.92% - 10.84% missing seeds with forward speed varying from 2.5 km.h⁻¹ to 3.5 km.h¹. The missing index of seed thus, reduced by 16–22% with incorporation of the sensor device with the planter. With increase in forward speed, seed rate decreased irrespective of use of the sensor with the planter due to higher planter vibration as well as the seeds dropping back from the metering cells in the seed box before being discharged in seed tube. However, using the sensor system, no significant effect of speed on seed rate was observed.