Experimental Investigation of Traction Power Transfer Indices of Farm-Tractors for Efficient Energy Utilization in Soil Tillage and Cultivation Operations

Farm tractors in cultivation consume a big amount of fossil fuels and emit greenhouse gases to the atmosphere. Improving traction performance and power transfer indices of wheeled tractors and field terrain soil with higher traction (pull ability) at optimal travel reduction (TR) can optimize energy utilization. This study compares the traction performance, fuel consumption, and field productivity, of a farm tractor equipped with a new drive wheel “rigid lugged wheel (RLW)” and conventional tire wheel (CTW) in field tillage operations. Tractor with RLW resulted 24.6 kN drawbar pull and 6.6 km.h−1 travel speed at 80% tractive efficiency and 15.6% TR. While with CTW, the drawbar pull and the travel speed were 23.2 kN and 6.0 km h−1 respectively at 68% tractive efficiency and 36.3% TR. The RLW resulted in improved traction performance with similar equipment weight. Tractor with RLW also resulted 220.5% lower TR, 14.8% higher field productivity, and 15.4% lower fuel consumption. RLW can control equipment weight and field traffic intensity with the improved traction performance of wheeled tractors and will make the field operations more energy-efficient and economical. For enhanced field drivability of RLW, further work is required to test for diverse field conditions and differently sized tractors.

Effect of soil moisture content, dynamic load and wheel slippage in measuring traction in an indoor traction bed

A study was conducted to determine the effect of soil moisture content, dynamic load and wheel slippage in measuring traction. A single wheel test rig was developed to enable fundamental research on traction studies on tropical soil at the department of Agricultural and Environmental Engineering of Federal University of Technology, Akure. This facility consists of a moving carriage with a trolley that moves in either forward or reverse directions on rails well above a soil bin powered by 2.2 kW, three phase induction motor. The present facility set up was able to operate in either towing test mode for tire motion resistance studies or driving test mode for tire net traction and tractive efficiency studies. The test tire on the moving carriage was powered to rotate by a motor with additional pull provided by a cable-pulley mechanism connected to a tower with hanging dead weights. All controls on the moving carriage were activated from the main control console. The developed facility was successfully tested to determine tractive efficiency for narrow wheels at a particular inflation pressure on clay soil. The single wheel test rig facility worked well and the research indicates that wheel load, wheel slippage, soil moisture content and inflation pressure has great effect on traction efficiency. Traction efficiency decreased as the wheel load and wheel slippage increased. The developed single wheel testing facility can perform traction tests in controlled soil conditions to study the effect of soil, tire and moisture parameters on the performance of the system.

Application of Soft Computing Techniques for the Analysis of Tractive Properties of a Low-Power Agricultural Tractor under Various Soil Conditions

Considering the fuel consumption and soil compaction, optimization of the performance of tractors is crucial for modern agricultural practices. The tractive performance is influenced by many factors, making it difficult to be modeled. In this work, the traction force and tractive efficiency of a low-power tractor, as affected by soil coefficient, vertical load, horizontal deformation, soil compaction, and soil moisture, were studied. The optimal work of a tractor is a compromise between the maximum traction force and the maximum tractive efficiency. Optimizing these factors is complex and requires accurate models. To this end, the performances of soft computing approaches, including neural networks, genetic algorithms, and adaptive network fuzzy inference system, were evaluated. The optimal performance was realized by neural networks trained by backpropagation as well as backpropagation combined with a genetic algorithm, with a coefficient of determination of 0.955 for the traction force and 0.954 for the tractive efficiency. Based on models with the best accuracy, a sensitivity analysis was performed. The results showed that the traction performance is mainly influenced by the soil type; nevertheless, the vertical load and soil moisture also exhibited a relatively strong influence.

Reliability and Efficiency of Tractive Force Generation by the Interlock Drive System

Tractors and other wheeled vehicles need considerable ballast to gain traction and have low tractive efficiency due to slip and tire flexing. The resulting soil degradation and energy cost are limiting factors that hinder the intensification of mechanical field management. The interlock drive system overcomes these limitations through the use of articulated spikes which temporarily interlock with the soil to generate traction. Once inserted into the soil, relatively thin and short spikes provide sufficient motion resistance to pull implements through the soil, with no need for additional ballast. To better understand the interaction of a spike with the soil, we conducted a series of experiments where we controlled the draft force and measured the resulting motion of the spike as it penetrates the soil and interlocks with it. Results show that the interlock drive system can generate pull reliably even on wet soil, and that a pull/weight ratio of 2 and higher is possible. The tractive efficiency for a vehicle using the interlock drive system can reach a ratio as high as 0.96 for wet and 0.975 for dry soil, as calculated from the experimental results. Precise soil applications would benefit from further improvement in the horizontal precision of soil penetration.

A Novel Traction Mechanism Based on Retractable Crampons to Minimize Soil Compaction and Reduce Energy Consumption

Tired and tracked tractors on agricultural soil have the inherent limitation of needing considerable ballast to gain traction and have low tractive efficiency due to slip and tire flexing. These limitations contribute to soil degradation and reduce the possibility to intensify mechanical field management. To address these disadvantages, we introduce a novel traction mechanism which combines inching or push-pull locomotion with retractable tines or crampons which penetrate the soil every few meters. Once inserted into the soil, relatively thin and short crampons provide sufficient motion resistance to pull tillage implements through the soil, with no need for additional ballast. Optimal crampon design depends on the width, depth in the soil, rake angle, and inter-crampon spacing. A hinged design allows for reliable crampon insertion and extraction. The pull/weight ratio of the vehicle can be controlled by placing the hinge low and by separating the crampon from the hinge by an arm. Travel reduction and tractive efficiency can be controlled through the actuation length of the push-pull mechanism. Experimental results show that crampons can achieve a high pull/weight ratio, travel reduction of less than 10%, and a tractive efficiency of over 90% on agricultural soil.

ARTIFICIAL NEURAL NETWORK AND STEPWISE APPROACH FOR PREDICTING TRACTIVE EFFICIENCY OF THE TRACTOR (CASE JX75T)

The aim of this study is to develop and predict models of tractive efficiency using the artificial neural network and stepwise approach. The tractive efficiency of tractor (CASE JX75T) was measured experimentally. Experiments were conducted in the site of Basrah University. Which had silty clay soil texture. The field conditions included effect of two level of cone index (550 and 980 kPa), two level of moisture content (8 and 21%), three forward speeds (0.54, 0.83 and 1.53 m/s) and four level of tillage depths (10, 15, 20 and 25 cm). The results illustrated that both developed models (stepwise approach and ANN technique) had acceptable performance for predicting tractive efficiency of tractor under various field conditions. However, ANN model outperformed stepwise model, where 4-7-1 topology showed the best power for predicting tractive efficiency with R-squared of 0.97 and MSE of 0.0074 with Levenberg-Marquardt training algorithm. The analysis of variance demonstrated that the studied parameters had single significant effect on tractive efficiency. The most parameter influential on tractive efficiency was tillage depth followed forward speed, cone index and moisture content.

Dimensional Analysis of the Tractor Tractive Efficiency Parameters

One of the important parameters of the tractor’s performance - tractive efficiency - should be improved during agricultural operation; this paper observes this parameter using the Arvid 354 tractor with a chisel plough. Parameters taken into account included the tillage parameters, such as tillage depth, travel velocity, rake angle, tine width and tractor weight, as well as soil engineering properties, including cohesion and soil bulk density. Experimental results indicated that the tractor tractive efficiency increased with increasing of the tillage depth and rake angle, whereas travel velocity did not show any specific impact on it. Theoretical equations were extracted for drawbar pull, tyre slip and gross traction using dimensional analysis and experimental data. Finally, by combining these equations, the tractive efficiency was estimated. Obtained model was evaluated by means of obtained experimental data. Results showed that the proposed model is capable of predicting tractive efficiency as a function of soil parameters, tractor weight and tillage parameters of the chisel plough.

Field performance of an agricultural tractor fitted with rubber tracks on a low trafficable soil

The introduction of rubber tracks on tractors has allowed more engine power per unit weight than with steel-tracked tractors, together with a reduction in soil compaction and higher on-road speeds. Recently, triangular rubber tracks able to be adapted on conventional wheeled tractors have been introduced. In this context, the goal of the paper is to evaluate the performance of a tractor with four triangular rubber tracks with respect to those of a wheeled tractor; the comparative tests consist of ploughing under on low trafficable and workable soil. The results obtained have shown a higher tractive efficiency, lower soil compaction and up to 20% lower specific fuel consumption for the fully tracked tractor. These results are in accordance with previous tests conducted with the triangular rubber tracks on highly trafficable soil, although in the present case, the dynamic traction ratio is markedly lower due to the low trafficable soil. The use of triangular rubber tracks is therefore justified on low trafficable soils and more in general on different soil conditions, since the soil is less compacted by such traction device.

Traction and drawbar performance characteristics of power tiller attached cage wheel

The study was carried out in the research farm of Indira Gandhi Agricultural University Raipur Chhattisgarh in June 2014. To evaluate drawbar and tractive power of 4.85kW of power tiller cultivator attached with two different types of cage wheel of half width (C1) and angle type wheels (C2) for a small power tiller operated in clay soil of wet land and flood condition. It was found that the maximum draft values of C1 and C2 were 1192N and 1039N in flood condition and 1318N and 1225N in wet condition. The results showed that maximum tractive efficiency was for cage wheel C1 and C2 values were 72.91% and 69.86% in puddle soil. The maximum field capacity was 0.084 ha/h for cage wheel C2 in puddle soil.BIBECHANA 13 (2016) 38-49