Traction Performance Research Articles

Prospects of Using a Pulsed Electrostatic Tractor With Nominal Geosynchronous Conditions

The geosynchronous (GEO) orbital regime is becoming cluttered with derelict space debris, which raises the collision risk for satellites in a very valuable orbit. Touchless reorbiting options have been proposed for moving this debris to a graveyard orbit to avoid the risk of physically docking with large, multiton defunct satellites that can be tumbling at several degrees per second. This paper investigates the electrostatic tractor (ET), which uses an electron beam mounted on a tug spacecraft to irradiate a passive debris object. The tug quickly rises to a positive steady-state voltage, and the debris quickly falls to a negative steady-state voltage to create an attractive tugging force. The tug maintains a fixed relative position during the reorbit using inertial thrusting. The Coulomb force can be used as a means of touchless actuation for geosynchronous debris reorbiting, detumbling, and formation flying. This paper investigates the prospects of using a beam with pulsed current. The off-pulsing periods can have benefits for sensing and thrusting applications, and the pulsing charging can lead to higher force levels for the same electrical power used in particular conditions. A Monte Carlo analysis is performed to study the mean electrostatic force, considering a range of beam currents, voltages, pulsing duties cycles, and vehicle sizes. Power-limited regions are identified where the pulsed tractor has a magnitude that is comparable or greater than the mean continuous beam force. This creates interesting alternate methods to implement an ET while having periodic off periods. The tractor performance is illustrated through the debris reorbiting scenario. A detailed equal power analysis determines that even duties cycles as low as 10%–20% can lead to forces comparable to the continuous beam performance, or even do better for some powers.

Viabilidade econômica e desempenho de trator agrícola utilizando óleo de girassol e diesel

<p style="margin-bottom: 0cm; line-height: 100%;" align="justify">Em estudos sobre uso como combustível para tratores agrícolas da mistura de óleo diesel com óleo vegetal, objetivou-se verificar a viabilidade econômica do seu uso como combustíveis de fonte renovável e o desempenho das máquinas agrícolas a campo. Diante disso, avaliou-se a viabilidade econômica e o desempenho de um trator agrícola, alimentado com óleo diesel e mistura diesel com óleo de girassol. O ensaio foi conduzido na Fazenda Experimental da Universidade Estadual de Maringá, Maringá – Paraná. Utilizou-se um trator agrícola MF 275, acoplado a um triturador de palha horizontal. Foi usado diesel B S10 (100%) e mistura de diesel (80%) com óleo de girassol (20%). O conjunto mecanizado foi submetido a três velocidades de deslocamento (3,00; 4,00; 5,00 km h<sup>-1</sup>) em duas condições de carga de trabalho, com carga (CC) e sem carga (SC). Utilizou-se o delineamento experimental em faixas, com 4 repetições, em esquema fatorial 2x3x2. Os dados foram submetidos ao teste F e Tukey a nível de 5% de probabilidade. O consumo do motor não diferiu com combustíveis testados. O trator com carga apresentou maior patinagem. O trator alimentado com a mistura de diesel com óleo de girassol teve maior custo horário percentual.</p>

Tractor Drawbar Performance Prediction Using Artificial Neural Network

Prediction of tractor drawbar performance can lead to simulation and optimization of tractor performance, allowing optimum setting of different parameters as well as guiding manufacturer in decision-making for design of new tractors. Twenty different input parameters were selected for drawbar performance prediction. The data used as input to train the network was collected from 141 tractor test reports tested between 1997 and 2013 at the Central Farm Machinery Training and Testing Institute, Budni (M.P.). A back propagation artificial neural network (ANN) was developed using Neural Network Toolbox in Matlab software. Matrix of 1140×20 and 1140×1 was made as input and target values for drawbar prediction in the ANN. The optimum structure of neural network was determined by trial-and-error method, and 30 different structures were evaluated. Highest performance was obtained for the network with two hidden layers, each having 35 neurons, and employed Levenberg-Marquardt training algorithm. Coefficient of determination (R2 ) and Mean square error (MSE) for this neural network was 0.994 and 1.284, respectively.

Modelling, simulation and applications of longitudinal train dynamics

ABSTRACTSignificant developments in longitudinal train simulation and an overview of the approaches to train models and modelling vehicle force inputs are firstly presented. The most important modelling task, that of the wagon connection, consisting of energy absorption devices such as draft gears and buffers, draw gear stiffness, coupler slack and structural stiffness is then presented. Detailed attention is given to the modelling approaches for friction wedge damped and polymer draft gears. A significant issue in longitudinal train dynamics is the modelling and calculation of the input forces – the co-dimensional problem. The need to push traction performances higher has led to research and improvement in the accuracy of traction modelling which is discussed. A co-simulation method that combines longitudinal train simulation, locomotive traction control and locomotive vehicle dynamics is presented. The modelling of other forces, braking propulsion resistance, curve drag and grade forces are also discussed. As extensions to conventional longitudinal train dynamics, lateral forces and coupler impacts are examined in regards to interaction with wagon lateral and vertical dynamics. Various applications of longitudinal train dynamics are then presented. As an alternative to the tradition single wagon mass approach to longitudinal train dynamics, an example incorporating fully detailed wagon dynamics is presented for a crash analysis problem. Further applications of starting traction, air braking, distributed power, energy analysis and tippler operation are also presented.

DYNAMIC TRACTION OF A MECHANIZED SET BASED ON TECHNICAL AND OPERATIONAL PARAMETERS

ABSTRACT The objective of this study was to evaluate and model the traction performance parameters of a tractor 4x2 FWD, according to the tractor speed, the internal pressure and the type of tires construction. For each type of tire construction was assembled an experiment in which we evaluated the influence of internal pressures of the front and rear tires and the speed of the mechanical assembly. It was found that the sliding of the diagonal run, presented significant effect in all variables analyzed, since the radial showed no influence of the factors evaluated. The power available in the drawbar was higher when the tractor was equipped for radial tires. The response variables, fuel consumption schedule and specific fuel consumption were more sensitive to the speed of the internal tire pressure. The fuel consumption per area worked, did not affect the analyzed variables. As for the effort prediction models in the tractor drawbar, it was only possible for diagonal run, which are influenced by speed and internal pressure levels of the front and rear tires.

Spline regression modelling of PTO performance of tractor fuelled with different biodiesels.

Abstract: The objective of this study was to investigate the possibility of fitting spline regression models for power take-off (PTO) performance characteristics of an agricultural tractor tested with four different fuels, including diesel fuel (B0) and three biodiesel blends made of canola oil (B10: 10% biodiesel + 90% petro-diesel blend; B20: 20% biodiesel + 90% petro-diesel blend; B30: 30% biodiesel + 90% petro-diesel blend). The performance characteristics evaluated were PTO power, engine torque, engine fuel consumption, and specific fuel consumption. Due to sharp slopes in measured quantities around the nominal engine speed (2200 r/min), compared to the standard regression method, the spline regression models suited well to the experimental data with coefficient of determination R2=0.99 for PTO power and engine torque. R2 varied between 0.97 and 0.99 for fuel consumption and 0.91 and 0.95 for specific fuel consumption. The weaker correlation found for specific fuel consumption could be attributed to profound fluctuations in measured data causing atypical pattern in the corresponding graphs around the nominal engine speed. It was concluded that splines were useful to accurately predict the measured PTO power and engine torque. Neither standard methods nor splines were sufficient to obtain very good regression models for specific fuel consumption. Keywords: biodiesel, performance characteristics, power take-off, tractor, spline modelling DOI: 10.3965/j.ijabe.20171003.3220 Citation: Aybek A, Arslan S, Ucgul M, Ucok S. Spline regression modelling of PTO performance of tractor fuelled with different biodiesels. Int J Agric & Biol Eng, 2017; 10(3): 115–120.

Potential productivity of the tractor

The agricultural tractor is designed to replace the live traction force with the main purpose - to increase the productivity of the farmer. But among the indicators of the tractor, characterizing its technical and technological level, there is no generalized performance indicator, reflecting the main property by which it would be possible to make a comparative evaluation of tractors of different models. The need to introduce an indicator of the productivity of the tractor has increased recently due to the significantly increased energy saturation. This increase in energy saturation is chaotic and is accompanied by a different mismatch in engine power and the weight of the tractor. There is a "surplus" power of the engine, which can not be used, because the traction force of the tractor is limited by its weight, and the speed of movement - by agrotechnical requirements. In these conditions, the introduction of the indicator of the tractor's performance in the number of indicators of the technical and technological level of the tractor acquires even greater urgency. The article defines the concept, substantiated and proposed a calculated indicator of agricultural tractor productivity - potential productivity. Potential productivity is proposed to understand the changeable design capacity of a tractor with a gun of such a width, at which its traction resistance is equal to the nominal design traction force of the tractor, and the speed of the machine-tractor unit is maximum for a given engine power, but does not exceed the speed established by the rules of agricultural technology. It is proposed to accept the potential performance of an agricultural tractor as one of its basic indicators of the technical and technological characteristics of the tractor in addition to the existing ones, and also to indicate in the list of technical parameters of the tractor.

Comparison of locomotive energy storage systems for heavy-haul operation

ABSTRACTThis paper modelled flywheel and battery energy storage systems for heavy-haul locomotives. Three heavy-haul trains with their traction power provided by diesel, diesel-flywheel, and diesel-battery locomotive consists were simulated on an existing railway. The diesel, flywheel, and battery locomotives have traction powers of 3100 kW, 2000 kW, and 3100 kW, respectively. Energy storages for the flywheel and battery ESSs are 500 kWh and 5000 kWh, respectively. Traction performance, fuel consumption, and emissions were compared for the three simulated trains. The results show that, compared with the diesel train, the diesel-flywheel and diesel-battery trains were 13.26% and 9.20% slower in speed, respectively. However, they decreased their fuel consumption by 12.40% and 20.65%, respectively, and consequently achieved the same percentage decreases for their respective emissions.

Влияние угла поперечного наклона поверхности качения на тягово-сцепные свойства колесного движителя

This article presents results of studies of the effect of movement surface slope on tractive and tow performance of wheeled forestry machine’s mover. Dependencies, which the mathematical model is based on, take into account the impact of direction deviations of the resultant load on soils from the gear from the normal, which reduces bearing capacity of the base and increases the deformation of soil and its resistance to machine movement. As a consequence, the model considers reductions of the mover’s tractive and tow performance.

A productivity model for first thinning of Pinus patula using a tractor and double-drum winch in South Africa

The productivity of skidding tractors in intermediate harvesting operations has not been determined in Mpumalanga, South Africa. The objective of this study was to develop a productivity model using a farm tractor in first thinning operations in Pinus patula compartments. A work study design was used to assess the performance of a skidding agricultural tractor. From 350 samples, important data variables collected were elemental times for each work cycle, extraction distance, slope and load volume. Stepwise and subsets regression analyses were conducted prior to multiple linear regression analysis. Analysis of variance was used to compare mean productivity estimates of the different models developed. Results showed that the best model was estimated by an interaction of distance × slope (ds), distance × load volume (dv) and slope × load volume (sv) as follows: ln(ŷ2) = 1.33–0.00154ds + 0.00174dv + 0.161sv. The mean estimate for this model was 5.036 m3 m h−1. The developed models predicted similar results to estimation results of the observed model, although there were statistically significant (P < 0.001) differences among mean estimates (3.6–5.5 m3 m h−1). All of the three models yielded R2adj. = 38%; SE = 0.458% at P < 0.001. It can be speculated that the remaining variation not explained by the models may be associated with long extraction distances, delays and the effect of slope as a main variable in the model. While the developed models mirrored reasonably well with the observed estimates of skidding productivity, these models should not be stretched to conditions dissimilar to those of their generation. Future research focus should be made on (1) effects of weather conditions and vehicular characteristics on skidding productivity and (2) the effect of winching lines on skidding productivity.

Performance of tractor operated seed drill for direct seeding in rice

The study was conducted to assess the performance of tractor operated seed drill for sowing of rice seeds at Krishi Vigyan Kendra, Dantewada. The field tests were conducted on sandy soil. The treatments were random transplanting of seedling at 35 to 45 days with two hand weeding (T 1 ) and direct drilling of rice seeds in friable soil condition by seed drill at the onset of monsoon with one hand weeding. The field capacity and average yield was found to be 0.46 ha/hr and 35.00 q/ha, respectively compared to 0.120 ha/hr and 29.90 q/ha observed in case of conventional method. The tractor operated seed drill was found to be better compared to conventional method of transplanting of paddy seedlings. The technology assessed better performance over farmers practice to reduce cost of cultivation and increase net profit.

Numerical Design and Analysis of the Tractive Performance of Large Off-road Wheels Driving on Dry Sands by DEM

Aimed at the typical condition of large off-road wheels operating on dry sands, in which the sand apparently gets discontinuous and rutted by lugged wheels with larger load, the numerical test for tractive performance is designed and analyzed by discrete element method. It is indicated from the analysis that: Off-road wheels equipped with paralleled lugs show the superiorly tractive performance, especially in aspects of adhesion and tractive force, while V-shaped lugs come second. Types of lugs have little relationship with the sinkage and the efficiency coefficients, which closely reach the maximum in range of 20%-30% of slip. Nonetheless, lugged wheels’ performance universally precedes a smooth one’s.

Influence of AC system design on the realisation of tractive efforts by high adhesion locomotives

ABSTRACTThe main task for heavy haul railway operators is to reduce the cost of exported minerals and enhance the long-term viability of rail transport operations through increasing productivity by running longer and heavier trains. The common opinion is that this is achievable by means of implementation of high adhesion locomotives with advanced AC traction technologies. Modern AC high adhesion locomotives are very complex mechatronic systems and can be designed with two alternative traction topologies of either bogie or individual axle controls. This paper describes a modelling approach for these two types of AC traction systems with the application of an advanced co-simulation methodology, where an electrical system and a traction algorithm are modelled in Matlab/Simulink, and a mechanical system is modelled in a multibody software package. Although the paper concentrates on the analysis of the functioning for these two types of traction control systems, the choice of reference slip values also has an influence on the performance of both systems. All these design variations and issues have been simulated for various adhesion conditions at the wheel–rail interface and their influence on the high traction performance of a locomotive equipped with two three-axle bogies has been discussed.

A Multiple Data Fusion Approach to Wheel Slip Control for Decentralized Electric Vehicles

Currently, active safety control methods for cars, i.e., the antilock braking system (ABS), the traction control system (TCS), and electronic stability control (ESC), govern the wheel slip control based on the wheel slip ratio, which relies on the information from non-driven wheels. However, these methods are not applicable in the cases without non-driven wheels, e.g., a four-wheel decentralized electric vehicle. Therefore, this paper proposes a new wheel slip control approach based on a novel data fusion method to ensure good traction performance in any driving condition. Firstly, with the proposed data fusion algorithm, the acceleration estimator makes use of the data measured by the sensor installed near the vehicle center of mass (CM) to calculate the reference acceleration of each wheel center. Then, the wheel slip is constrained by controlling the acceleration deviation between the actual wheel and the reference wheel center. By comparison with non-control and model following control (MFC) cases in double lane change tests, the simulation results demonstrate that the proposed control method has significant anti-slip effectiveness and stabilizing control performance.

Analisis Kinerja Traksi Roda Besi Bersirip Di Lahan Sawah

Analisis Kinerja Traksi Roda Besi Bersirip Di Lahan Sawah

Kinerja Traksi Roda Ramping Bersirip pada Berbagai Kombinasi Jumlah dan Sudut Sirip di Tanah Sawah Berlumpur

Kinerja Traksi Roda Ramping Bersirip pada Berbagai Kombinasi Jumlah dan Sudut Sirip di Tanah Sawah Berlumpur

Effects of Some Properties of Drive Tires Used in Horticultural Tractors on Tractive Performance

Many studies on tractive performance of tractor tires have been carried out to solve soil-wheel interaction problems in the last decades. The purpose of this study is to experimentally determine effects on tractive performance of radial and bias-ply drive tires at three different tire lug heights, axle loads and inflation pressures. The experiments were carried out in stubble field conditions. To obtain sufficient performance data, a new single wheel tester was designed and manufactured. Travel reduction, net traction ratio and tractive efficiency varied from 3.3% to 34.1%, 0.24 to 0.93 and from 0.27 to 0.78 respectively depending on drawbar pull. The effects of tire type, lug height, dynamic axle load and inflation pressure on tractive efficiency were found significant (P<0.01) by the performed variance analysis and LSD tests. Radial tires provide better tractive performance compared with bias-ply tires. The tractive efficiency increased especially with increasing dynamic axle load and decreased with increasing tire inflation pressure. Tire dynamic axle load was the major contributory factor on tractive performance as compared with other independent variables. For a given drawbar pull, it was observed that tractive efficiency of radial tire can be maximized by selecting appropriate levels of lug height, dynamic axle load and inflation pressure.

The Coordinated Control of Wheeled Mobile Robot on Loose Soil

Generating the coordinated tractive force of each wheel for the robot is an important control objective in order to ensure the wheels to be the driven wheel but not the towed wheel. The tractive force is different between the front wheel and the following rear wheel because of the wheel’s unequal sinkage caused by the compaction of loose soil. In this study, the mathematical model of sinkage is established to investigate the influence of repetitive passing on wheel sinkage, and the wheels’ tractive performance is deduced on basis of the terramechanics. The equal drawbar pull generated by all the wheels under the optimal efficiency analysis is defined as the index to evaluate the wheel’s motion consistency, as well as the coordinated control objective of wheeled mobile robot on loose soil. Furthermore, dynamic model of a six-wheel mobile robot is established and the fuzzy sliding mode controller is designed. Meanwhile, the validity of the proposed modeling and control method is demonstrated through the ADAMS co-simulation model. The result shows that control system has good performance in simulation.

Numerical analysis on tractive performance of off-road wheel steering on sand using discrete element method

This paper presents a numerical analysis on steering performance including tractive parameters and lug effects. To explore the difference between the turning and straight conditions of steering, a numerical sand model for steering is designed and appropriately established by the discrete element method on the basis of triaxial tests. From the point of mean values and variation, steering traction tests are conducted to analyze the tractive parameters including sinkage, torque and drawbar pull and the lug effects resulting from type, intersection and central angle. Analysis indicates that steering motion has less influence on the sinkage and torque. When the slip ratio exceeds 20%, the steering drawbar pull becomes increasingly smaller than in the straight condition, and the increase of steering radius contributes to a decline in mean values and a rise in variation. The lug effect of central angle is less influenced by the steering motion, but the lug intersection is able to significantly increase the steering drawbar pull along with the variation reduced. However, the lug inclination reduces the steering drawbar pull along with the variation raised in different degrees.

Taking Traction Control to Task: High-Adhesion-Point Tracking Based on a Disturbance Observer in Railway Vehicles

Railway vehicles have been based on a wheel-rail system since the system's origination. Therefore, the adhesion-coupling behavior between wheel and rail is the fundamental element of railway traction [1]. However, low vehicle wheel-rail adhesion caused by high humidity, rain, snow, oil, or decomposing leaves is a common problem that can cause damage to some elements of the traction system and decrease traction performance [2]. It may even give rise to safety problems and reduce comfort, not to mention delays and their corresponding economic impact. Good traction control to ensure the system is working at high adhesion point is therefore critical and mandatory for the traction control units (TCUs) [2]-[6].