Improving steering system for walking tractor-trailer combination to increase operator’s comfort and ease of control

The aim of present study was to develop the performance of walking tractor-trailer combination, increase the ability of control and steering, maneuverability, reduce the hand transmitted vibration (HTV), discomfort, stress and probability of accident for walking tractor operators.  The location of controls in existing walking tractor with respect to anthropometric suitability of operators and rearrangement for improved operator's ergonomics was analyzed.  To compare existing system with improved system, and find the affects of improved workplace layout over the existing one in terms of physiological cost and discomfort of the walking tractor operator, turning radius, operator hart rate, energy cost and HTV were measured.  The energy cost of riding walking tractor-trailer with improved workplace layout is 9.2% lesser than that of riding unmodified walking tractor-trailer.  The overall discomfort and body part discomfort of operator riding walking tractor-trailer with improved workplace layout were reduced by 38.5 and 17.9% walking tractor-trailer with and without improved work space layout.  The HTV was measured and analyzed as per the guidelines of International Standards ISO 5349 (1986 Vibration was measured using the portable four-channel multi-analyzer system.  The data collection included frequency-unweighted and frequency-weighted vibration in RMS acceleration, frequency response of the vibration.  The HTV reduction of the walking tractor with trailer at the handles for steering system was improved from 10.1 to 11.6% and from 11.9 to 17.3% on farm road and concrete road respectively at selected levels of forward speed of operation.  The turning radius decrease from 6.2 to 2.7, 6.7 to 2.8 and 7 to 3 meters for unmodified and modified walking tractor respectively at the speed of 3, 4 and 5 km/h.  Average operator hart rate has reduction at the rate of 20% for modified compared to unmodified walking tractor.  Reduction in operator heart rate was because of fixing the handle steering and convenience during the operating

Development of Prediction Models for Soil Nitrogen Management Based on Electrical Conductivity and Moisture Content

A study was conducted with the goal of developing an algorithm for use in sensors to monitor available soil N. For this purpose, three different soils were selected. The soils were studied for electrical conductivity (EC) at four different moisture levels and four levels of N. The selection of moisture levels was based on optimum moisture levels between tillage moisture and field capacity. The results revealed a significant relationship between electrical conductivity and moisture level of the soil as well as between electrical conductivity and soil N content. Based on these relations, a polynomial model was developed between the EC of each selected soil sample and moisture content as well as N levels. The regression model for moisture content-based EC determination had coefficients of determination of 0.985, 0.988, and 0.981 for clay loam, sandy loam, and sandy loam soils, respectively. Similarly, the regression model for N content-based EC determination had coefficients of determination of 0.9832, 0.9, and 0.99 for clay loam, sandy loam, and sandy loam soils, respectively. An algorithm developed using a polynomial relationship between the EC of each selected soil sample at all moisture and N levels can be used to develop a sensor for site-specific N application

Performance Assessment of a Sensor-Based Variable-Rate Real-Time Fertilizer Applicator for Rice Crop

Variable-rate technology (VRT) may reduce input costs, increase crop productivity and quality, and help to protect the environment. The present study was conducted to evaluate the performance of a variable-rate fertilizer applicator for rice (Oryza sativa L.). Three replications were conducted, each of which was divided into four plots. Field performance of the system was assessed at different nitrogen levels (N1 to N4, i.e., 75, 125, 175, 225 kg ha−1), growth stages (tillering, panicle initiation, heading), and heights (40, 60, 80, 100 cm) of the sensor from the crop canopy. Fertilizer rate was at minimum 12.59 kg ha−1 at 10 rpm of drive-shaft rotational speed and at maximum 50.41 kg ha−1 at 40 rpm. The system response time was within the range of 3.53 to 4.93 s, with overall error ranging between 0.83% to 4.92%. Across different growth stages, when fertilizer rate was increased from N1 to N4, NDVI increased from 0.49 to 0.69. Hence, drive-shaft rotational speed is decreased from 25 to 7 rpm to shift the application rate from 30.83 to 9.15 kg ha−1. There was a 45% reduction in total fertilizer rate applied by the system, with respect to the recommended rate