Tractor Wheel Research Articles

MODIFICATION AND PERFORMANCE EVALUATION OF AN IMPORTED THREE-ROW ANIMAL-DRAWN MAIZE PLANTER FOR PLANTING SOYBEANS

Increase in demand of functional and affordable planters and the inability of the peasant farmers in Nigeria to purchase imported planters stressed the need for development of a locally produced planters that could address the challenges encountered in grain planting. A three row imported animal-drawn maize planter was modified having identified its deficiencies. The modified planter consists of hopper, seed metering device, delivery tube, furrow opener, covering device, pressing wheel, frame, handle and traction wheel. It was evaluated in the laboratory and field using maize and Soybean as test crops. Parameters determined are planting speed, seedling emergence, plant to plant spacing, effective field capacity, germination count, planting efficiency, seed delivery rate, number of seeds per hole and percent seed damage. A combination of three planting speeds (2, 1.1 and 0.8m/s) and three seed weights (2.9, 2.2 and 1.1kg) were used for the performance evaluation. Results obtained were analyzed in a Completely Randomized Block Design. It showed that seed delivery rate was 24.8kg/ha and effective field capacity was 0.12ha/ha while the highest germination count of 83% was obtained at 0.8m/s planting speed and 2.9kg seed weight. The best of planting efficiency of 86.4% was obtained at 1.1m/s planting speed and 2.9kg seed weight. Plant to plant distance of 26.4cm was obtained at 2m/s planting speed and 2.2kg seed weight. One seed per hill was obtained at the all combinations. The modified planter has proved to be suitable for eliminating the limitations associated with the imported planter.

ОСОБЕННОСТИ КОНСТРУКЦИИ ТРАКТОРОВ ДЛЯ РАБОТЫ НА СКЛОНАХ

The problems of creating tractors, self-propelled chassis, forestry and agricultural machines of special designs for the mechanization of crop production, land reclamation and construction in hard-to-reach conditions of forest, agricultural and mountain lands are considered in the work. A comparative analysis of design solutions that have found application in domestic and foreign tractors used in the performance of technological and transport operations on sloping lands and badlands in agriculture and forestry is given. It is noted that a number of models of universal row-crop tractors provide for the possibility of increasing stability by turning the housings of the remote final drives relative to the rear axle housing. For tractors, at the same time, the wheelbase increases and the ground clearance (ground clearance) decreases. It is indicated that the analysis of the features of the operation of wheeled tractors on the slopes made it possible to substantiate the methods and means that improve their main indicators: differential lock; lowering the center of gravity; the use of tires with high lugs, additional steel wheels, lugs, expanders; the use of half-tracks and wheeled tractors with a 4K4 wheel arrangement. The advantages and disadvantages of using tracked and wheeled tractors as the base machine have been established. Slope preference for tractors with front drive axle. Such tractors, equipped with the previously listed devices, have better traction properties, maneuverability and controllability, approaching caterpillar tractors in these indicators. Recommendations for the implementation on slopes, forest and agricultural lands of all-wheel drive low-clearance wheeled tractors are given in the work. In conclusion, it is indicated that, despite the considered features, when creating tractors for working on small-contour plots located on slopes up to 25 °, preference is given to wheeled low-clearance tractors, which is caused by a cheap design due to minor design changes compared to the basic models.

Position and Speed Control of the Tractor-Trailer Robot by Considering the Dynamics of the Tractor Wheels Using the PID Controller

Position and Speed Control of the Tractor-Trailer Robot by Considering the Dynamics of the Tractor Wheels Using the PID Controller

Performance of Disc and Chisel Ploughs and their Effects on Some Soil Physical Properties

A study was carried out at the University of KhartoumDemonstration Farm in (2007), to study the performance of two tillageimplements: (disc and chisel plough) and their effect on some soilphysical properties. The results showed that the higher values of boththeoretical and effective field capacities were recorded by chisel plough(1.23 ha/hr and 0.90 ha/hr) as compared to disc plough (0.63 ha/hr and0.50 ha/hr). The higher field efficiency was recorded by disc plough(79.37%) as compared to the chisel plough (73.4%). The fuel consumedwhen using the disc plough was (10.60 l/ha) less than that consumed bythe chisel (13.47 l/ha). Tractor wheel slippages ware found to be 10.92%.and 14.1%. The result also showed that both ploughs decreased the soilbulk density values from 1.54 g/cm3 to 1.51 and 1.49 g/cm3 by disc andchisel plough respectively. Particle density was not affected (P > 0.05) byboth implements . The soil porosity values were also increased for bothimplements. The soil moisture content recorded in two depths 0-15 and15-30 cm were higher for chisel plough (6.53% and 6.9%) as compared todisc plough which recorded 6.3% and 6.5% respectively. The infiltrationrate obtained by the disc plough was 22.2 cm/hr while that of chiselplough was (20.1 cm/hr)

Performance of Disc and Chisel Ploughs and their Effects on Some Soil Physical Properties

A study was carried out at the University of KhartoumDemonstration Farm in (2007), to study the performance of two tillageimplements: (disc and chisel plough) and their effect on some soilphysical properties. The results showed that the higher values of boththeoretical and effective field capacities were recorded by chisel plough(1.23 ha/hr and 0.90 ha/hr) as compared to disc plough (0.63 ha/hr and0.50 ha/hr). The higher field efficiency was recorded by disc plough(79.37%) as compared to the chisel plough (73.4%). The fuel consumedwhen using the disc plough was (10.60 l/ha) less than that consumed bythe chisel (13.47 l/ha). Tractor wheel slippages ware found to be 10.92%.and 14.1%. The result also showed that both ploughs decreased the soilbulk density values from 1.54 g/cm3 to 1.51 and 1.49 g/cm3 by disc andchisel plough respectively. Particle density was not affected (P > 0.05) byboth implements . The soil porosity values were also increased for bothimplements. The soil moisture content recorded in two depths 0-15 and15-30 cm were higher for chisel plough (6.53% and 6.9%) as compared todisc plough which recorded 6.3% and 6.5% respectively. The infiltrationrate obtained by the disc plough was 22.2 cm/hr while that of chiselplough was (20.1 cm/hr).

EVALUATION ANALYSIS OF THE RUNNING SYSTEM SOIL INTERACTION OF WHEELED AGRICULTURAL TRACTORS

The article provides an evaluative analysis of the wheeled agricultural tractor’s running systems soil interaction. A sample of more than 600 MFWD tractors of the world's leading manufacturers was subject to analysis. To determine the parameters of the maximum soil pressure, the value of the footprint gross flat plate area is applied, assuming that the tires are operated under conditions characterized by the speed index A6 with a significant torque for a long time. It is obtained the calculated function of the probability distribution of the maximum pressure on the soil of a sample of modern wheeled tractors with a fixed location of the centre of gravity (weight distribution). The designed arrangement of the centre of gravity of tractors by groups with the corresponding rolling circumference indexes difference ΔRCI =4...9 was analysed. It was established that for general and universal purpose tractors with ΔRCI = 4...6 the most common weight distribution coefficient is 0.40 or 0.44. For special (utility) tractors with ΔRCI = 7...9, the most common weight distribution coefficient is 0.45...0.46. An analysis of the maximum soil pressure in a wide range of the traction force of the tractor while maintaining a constant optimal weight distribution, which depends on the ratio of the footprint gross flat plate area of the front and rear tires, was carried out. The analysis showed that maintaining a constant optimal weight distribution during traction operations makes it possible to reduce the maximum pressure on the soil by 8...40 kPa. This makes it possible to increase the part of the territory of Ukraine, where modern wheeled tractors with single tires can be operated without violating agro-ecological requirements, by 14%.

ANALYSIS IN DEVELOPMENT OF TRANSMISSIONS FOR MODERN WHEELED TRACTORS

The increase in the production of agricultural food products leads to the creation of energy-rich wheeled tractors, which are able to realize the power of the engine by increasing the speed of movement (productivity) or traction characteristics. But this direction of development has a counterbalance in environmental protection actions. So, in the European Union, emissions of carbon monoxide, hydrocarbons, nitrogen oxides, solid particles, etc. are limited for off - road vehicles. The outlined directions of development are of a contradictory nature, so tractor manufacturers are trying to create transmission units designed to meet the performance and environmental needs of a wheeled tractor. Therefore, the material of this article aims to analyze the technical solutions of the world's tractor manufacturers in the construction of transmissions of wheeled tractors. When solving the set goal, a technique was used, which involved analysis by the method of torque transformation (stepped and stepless) and the principle of action (mechanical, hydraulic, electric). As a result, the models of such tractor manufacturers as: Case IH, Claas, Deutz-Fahr, Fendt, John Deere, Massey Ferguson, New Holland, Steyr, Valtra were analyzed. The practical significance of the work lies in the provision of recommendations on current technologies for the construction of transmissions of wheeled tractors.

BALLASTING AND DUAL TIRES USING OF WHEELED AGRICULTURAL TRACTORS UNDER THE CONDITIONS OF FULFILLING AGRO-ECOLOGICAL STANDARDS FOR SOIL INTERACTION

The article presents an analytical approach to the implementation of ballasting and dual tires using of agricultural wheeled tractors, which is based on the unconditional fulfilment of agro-ecological standards of tires soil interaction. The necessity of harmonizing the indicators of the position of the centre of gravity of the tractor, the footprint area of the front and rear tires ratio, as well as their load capacity is shown. The need to use equal flotation in tractor’s tires during single and double use has been proven, which determines the need to maintain the position of the centre of gravity during ballasting. The method of selecting the mass of ballast weights for installation in the rear wheel discs and the front linkage system of the tractor, as well as the ballast weight system, which makes it possible to ensure the maximum possible weight of the tractor to meet the agro-ecological requirements regarding the maximum pressure on the soil, is proposed. The perspective of dual tires using to reduce the maximum pressure of the tractor on the soil is shown, and the high efficiency of ballasting the tractor on dual tires is also proven. The example shows the possibility of increasing the part of the territory of Ukraine where it is possible to operate the tractor without violating agro-ecological norms by 20-40% due to the use of dual tires. The possibility of increasing the efficiency of the tractor up to 1.5 times due to ballasting and doubling of tires has also been proven. The obtained data are based on 20 calculation variants of the tractor with different degrees of ballasting and the use of different tire doubling schemes.

JUSTIFICATION OF THE IMPLEMENTATION OF THE WHEELED TRACTOR CAB SUSPENSION SYSTEM

Today, there is a significant mechanization of agriculture, which is designed to facilitate the work of the driveroperator and prevent the driver-operators from getting health problems during the performance of agricultural work. Therefore, such processes become a priority, because the increase in the energy content of tractors, the increase in speed during the execution of technological and transport operations, the variety of machines and tools aggregated by the tractor - inevitably lead to an increase in the impact of vibrations on the body of the operator-driver. In order to create real competition, domestic manufacturers need to implement modern solutions, which is not possible without high-quality cooperation with scientists. Therefore, the material of this article aims to analyze the implementation of the suspension system of the cab of a wheeled tractor on the indicators of smoothness of the wheeled tractor (vertical accelerations on the seat) when moving on various road surfaces. When solving the set goal, a technique was used that involved the use of the Dalembert principle, i.e., in the calculation model of the system from the massive elements, all available bonds were conditionally broken, then the action of the discarded bonds was compensated by the reactions of the bonds. As a result, the dependence of the change in vertical accelerations on the seat of the driver-operator of the KhTZ-160U tractor on the speed of movement (frequency of external influence) when moving on surfaces was obtained. The practical significance of the work lies in the provision of positive evaluation results regarding the reduction of the impact of vibrations on the body of the operator-driver for the domestic tractor industry through the introduction of the cabin suspension system.

REVIEW OF VIBRATION-BASED SURFACE & TERRAIN CLASSIFICATION FOR WHEEL-BASED ROBOT IN PALM OIL PLANTATION

Palm oil can grow in almost flexible topography. On flats, slopes, hilly, or undulating areas and whether on inland or reclaimed coastal areas. This makes the palm oil plantation environment unique with various soil types & surfaces. Each surface has a unique physical characteristic that directly influences the driving, handling, power efficiency, stability and safety of a robot. A mobile robot should have knowledge not limited to obstacles, but also the surface that the robot traverses to estimate wheel slippage and apply corrective measures. This paper discusses the harshness factors in palm oil plantation estates and the effects on wheel traction. We then present our review of several vibration-based surface classification techniques. Based on our survey, a combination of multimodal sensory for surface classification is more suitable to identify surfaces and terrain in palm oil plantations.

Driving System Design and Power Source Parameter Optimization of Tractor with Dual-Motor Coupling Drive

For the poor working conditions of tractors, single-motor drive tractors usually choose a motor with large parameters, which leads to the lower efficiency of the motor under low-load conditions. Taking a wheeled tractor of YTO as the research object, a driving scheme of a dual-motor electric tractor was proposed, and the main components of the tractor electric drive system were matched. Based on MATLAB/Simulink, the electric tractor drive system model was established. On the premise of meeting the dynamic needs of the tractor, an optimization model was established with the tractor power consumption as the optimization goal and the power distribution coefficient of dual motors as the decision variable. The optimization model was solved by a genetic algorithm. The driving characteristics of the optimized electric tractor and the original tractor, as well as the instantaneous power consumption and total power consumption of the tractor before and after optimization, are compared and analyzed. The results show that the traction efficiency of the optimized electric tractor is about 2.7% higher than that of the original tractor, and the total power consumption of the electric tractor before and after optimization is reduced by 8.2%. The power performance and economy of the tractor after parameter matching and optimization are significantly improved.

К РАСШИРЕНИЮ ЭКСПЛУАТАЦИОННЫХ ХАРАКТЕРИСТИК ЗЕМЛЕРОЙНО-ТРАНСПОРТНЫХ МАШИН

This article presents materials related to the development of a promising dump design for various types of bulldozers used on high-strength soils. The most important parameter of bulldozers is productivity, which depends on the amount of soil moved by the blade in one working cycle, characterized by the volume of the drawing prism. A characteristic sign of overloading of dumps is the slipping of tracks or tractor wheels. This phenomenon significantly affects the reliability of components and parts of bulldozers, reducing their productivity. To eliminate this, rotary dumps can be used, allowing them to be rotated at a certain angle in both directions relative to the longitudinal axis of the machine, but their restructuring is quite time-consuming and not always effective. The analysis of numerous sources made it possible to develop a prom-ising technical solution at the level of inventions, which makes it possible to efficiently perform earthmov-ing operations related to the treatment of high-strength soils. As a result of analytical studies, taking into account the cutting resistance force of 7 kN, the geometric parameters of the gear engagement (gear wheel-rail) were calculated, the engagement module was adopted m = 10 mm. Recommendations are given on the choice of gear wheel and rail material – 45 normalized steel. For angular rotations of the side sections of the blade, it is recommended to use a hydraulic cylinder with a double-sided rod with an internal cylinder diameter of dv = 40 mm and a rod diameter of ds = 20 mm, at a working fluid pressure of p=10 MPa. It is recommended that the blade rods be made of 80x60 Steel 85 pipe, which ensures their stability during the operation of the bulldozer blade.

Design and manufacture of four wheel tractor for medium size work rice farming

<span>Indonesia is located at the equator occupy areas north and south of its bearing atmosphere where about 270 million people live the land of very rich soil and are also rich in mineral sediment demanded heavily for today's technology including nickel, bauxite, lithium, and aurum with its close articles such as thin and uranium. So numerous heavy mining equipment works around the clock. Unfortunately, the other potential products of the rich soil were somehow neglected as the nation left such activities to its traditional practice by utilizing man and animal to cultivate the plantation, so that the productivity of the land from the surface is very minimal such that the average productivity of the soil only reach 27% compared to its champion in the developed countries per acre per year. The study on such low soil productivity is caused by two main problems, such that the lack of massive soil processing technology and low attraction for the worker to pursue their career in farming as more money is offered by the transportation sector being an online transport business. This article is a series published on the tractor research initiative that aims to provide a functional medium tractor powered by a 30 HP engine that can do the basic work of a tractor including lifting soil on the surface so that oxygen will fill up the soil and the mineral can reach the root of the plant life on it and kill the unfavorable weeds in the process. The article will discuss all functional elements of the tractor and necessary specifications from design, manufacturing, and final assembly. Further publications will involve optimal design and construction to head for the final products of its commercial endeavor.</span>

Determination of dynamic and traction-energy indicators of all-wheel-drive traction-transport machine

The results of a study of dynamic and traction-energy indicators of an all-wheel drive wheeled traction-transport machine are presented. A diagram of a dynamic transmission model for an all-wheel drive wheeled traction and transport machine and a system of equations for the transmission dynamics in the Cauchy form have been compiled. This made it possible to determine the dependences of the angular speeds of rotation of the transmission elements of the traction-transport machine, the dependences of the torques and the dependences of the contacting traction forces on the wheels on time. The method allows to determine the optimal transmission parameters, differential designs and gear ratios to improve the traction and coupling and fuel-economic performance of the machine. It has been established that the angular speeds of rotation of the front wheels of the traction-transport machine 1.29 rad/s, 1.27 rad/s are higher than the angular speeds of rotation of the rear wheels 1.24 rad/s, 1.25 rad/s, which leads to the appearance of a kinematic discrepancies and additional energy losses. The torques of the front drive wheels are 6972 Nm, the rear drive wheels are 4622 Nm. The contacting traction forces on the front wheels of the machine are 5478 N after the end of the acceleration of the machine, on the rear wheels – 3473 N. Experimental studies were carried out on the example of an all-wheel drive wheeled tractor with an articulated frame to validate the method for assessing the dynamics of the traction-transport transmission. The difference between the values of the angular speeds of rotation of the wheels and the tangential traction forces on the wheels, determined theoretically and obtained during experimental studies, is 2 %. The developed method for assessing the transmission dynamics of an all-wheel drive traction and transport machine should be considered valid. The method proposed in the paper can be used to assess the dynamics of wheeled machines

Engineering Design, Kinematic and Dynamic Analysis of High Lugs Rigid Driving Wheel, a Traction Device for Conventional Agricultural Wheeled Tractors

Traction failure on loose terrain is common in conventional agricultural wheeled tractors due to poor traction ability and lower power transfer efficiency of drive wheels, which leads to excessive energy consumption and soil compaction in agriculture. To overcome the problem, this paper presents a new design of a rigid lugged wheel for use in field tillage operations. This wheel was designed according to field operational requirements and also provided with rubber pads for smooth on-road drives. Kinematic and dynamic analysis of new wheel designs were carried out to study how they move, how they interact with the soil, and how they generate drive force in loose terrain soil. The relationship of wheel lug motion trajectories, displacement, and velocity of the wheel relative to field conditions, different travel reduction rates, and lug penetration/wheel sinkage were analyzed. Wheel-terrain interaction and shear stress-shear displacement relationships when the wheel is driven in soft, deformable terrain were studied using classic soil mechanics principles. It is found that the component of thrust in the direction of driving, i.e., driving force, is ranged between 81.52% and 86.17%, while the vertical component is reported to be less than 30% and further decreases to 9%, which is the compaction avoiding factor. The relationships, thus developed, of wheel parameters, soil stress and thrust characteristics, and wheel drive force were derived and revealed that the traction performance, power transfer efficiency, and trafficability of tractors in loose terrain can be improved by using the newly proposed wheel. A finite element method was used to analyze the designed wheel model for structural stability and optimization. The theoretical analysis results of the new drive wheel are convincing, so further tests and field operation research are recommended for sustainable adoption.

The Failure Analysis of Unintended Elevator Car Movement Protection

The unintended movement protection device of elevator car can prevent the accident of passenger shearing and extrusion caused by the fracture of elevator traction wheel shaft and the failure of control system components. However, due to the relatively complex composition of this device, many car accidental movement protection devices in the actual use process do not meet the requirements of standards and specifications. In view of the problems found in the inspection, several typical failure cases are summarized, and the reasons for the failure of these devices are analyzed. At the same time, the corresponding solutions under the current technical conditions are put forward, which provides a reference for the development of field inspection and the revision of specifications and standards.

Підвищення ремонтопридатності автотракторної техніки застосуванням раціональної кількості інструменту

The conducted systematic analysis of maintainability indicators allows establishing their connection with other reliability properties and classifying these indicators according to technical and economic criteria. On this basis, the technological component of maintenance and repair, which ensures the provision of spare parts, tools and means of technical condition control, was selected and investigated. Set of indicators that allow to evaluate and standardize the maintainability of means of transport most fully and in accordance with modern requirements is proposed.The dependence was obtained for determining the required number of tools in a set of spare parts, tools and accessories (STA), which takes into account the reliable characteristics of the machine and the characteristics of the process of restoring its operability under real operating conditions.The approach to calculations of rational sets of tool equipment for vehicle machinery is proposed on the example of the chassis of the domestic wheeled tractor KhTZ-17221, the corresponding calculations are performed. The conducted analysis shows that with the existing service system and the level of reliability of the KhTZ-17221 tractors in real operation conditions to ensure the readiness factor within 0.85-0.95, the presence of tools in the equipment kit has a significant impact.The analysis of the obtained dependence shows that in order to quickly eliminate the consequences of the failures of the KhTZ-17221 tractors, it is necessary to have a complete set of tools in the set of STA, provided for in the operating instructions. Otherwise, the operative time for eliminating failures increases, which leads to unjustified downtime of equipment and increased costs for consumers, especially during periods of agricultural work. When increasing the number of tools in the kit of STA to the level regulated by the factory documentation, while maintaining all other parameters, it is possible to increase the readiness factor in real operation from 0.84 to 0.92. That is, the presence of tools significantly increases the efficiency of vehicles using in real operation conditions.The obtained results can be used to improve maintainability indicators

Research on the Slip Rate Control of a Power Shift Tractor Based on Wheel Speed and Tillage Depth Adjustment

The existing control methods for the slip rate of the driving wheel of a test prototype have limitations that cause low-quality tillage and finishing operations. We propose a slip rate control method based on the dual factor adjustment of wheel speed and tillage depth, taking the power shift tractor New Holland T1404 as an example to verify the algorithm. This method employs the wheel speed control principle based on the power transmission ratio calculation, throttle adjustment, and wheel speed control methods, as well as the slip rate control method, with wheel speed–slip rate control as the main factor and tillage depth–slip rate control as the secondary factor. A tractor test prototype was built to validate the method. The wheel speed control method enabled the tractor to accurately control the wheel speed under three working conditions: no load on a cemented ground, no load in a field, and subsoiling operation. For the subsoiling operation, the slip rate control method gradually reduced the tractor wheel speed when the slip rate of the tractor’s drive wheel was too high until it met the requirements. When the wheel speed was adjusted to the lower limit, suspension control was performed to reduce the tillage depth and improve vehicle trafficability. In the 130 s validation test, it took 14.1 s for the tractor with the slip rate control function to have a wheel slip rate exceeding 20%, which was 25.4% lower than that of the tractor without this function. The proposed method controls the slip rate within the optimal range while ensuring maximum operation quality (tillage depth).

LQR Trajectory Tracking Control of Unmanned Wheeled Tractor Based on Improved Quantum Genetic Algorithm

In the process of trajectory tracking using the linear quadratic regulator (LQR) for driverless wheeled tractors, a weighting matrix optimization method based on an improved quantum genetic algorithm (IQGA) is proposed to solve the problem of weight selection. Firstly, the kinematic model of the wheeled tractor is established according to the Ackermann steering model, and the established model is linearized and discretized. Then, the quantum gate rotation angle adaptive strategy is optimized to adjust the rotation angle required for individual evolution to ensure a timely jumping out of the local optimum. Secondly, the populations were perturbed by the chaotic perturbation strategy and Hadamard gate variation according to their dispersion degree in order to increase their diversity and search accuracy, respectively. Thirdly, the state weighting matrix Q and the control weighting matrix R in LQR were optimized using IQGA to obtain control increments for the trajectory tracking control of the driverless wheeled tractor with circular and double-shifted orbits. Finally, the tracking simulation of circular and double-shifted orbits based on the combination of Carsim and Matlab was carried out to compare the performance of LQR optimized by five algorithms, including traditional LQR, genetic algorithm (GA), particle swarm algorithm (PSO), quantum genetic algorithm (QGA), and IQGA. The simulation results show that the proposed IQGA speeds up the algorithm’s convergence, increases the population’s diversity, improves the global search ability, preserves the excellent information of the population, and has substantial advantages over other algorithms in terms of performance. When the tractor tracked the circular trajectory at 5 m/s, the root mean square error (RMSE) of four parameters, including speed, lateral displacement, longitudinal displacement, and heading angle, was reduced by about 30%, 1%, 55%, and 3%, respectively. When the tractor tracked the double-shifted trajectory at 5 m/s, the RMSE of the four parameters, such as speed, lateral displacement error, longitudinal displacement error, and heading angle, was reduced by about 32%, 25%, 37%, and 1%, respectively.

Design and Dynamic Characteristics Analysis of Novel Support Adjustment Mechanism of Wheeled Downhole Tractor

Conventional design method of the downhole tractor is based on cementing casing, which is only suitable for the smooth wellbore. For the open hole well, the conventional downhole tractor has poor adaptability and even cannot work normally. In order to improve the obstacle surmounting performance of the wheeled downhole tractor (WDR) and expand the application range of the WDR, a double push rod-double spring support adjustment mechanism (DPRDSSAM) is proposed in this paper. Meanwhile, the proposed DPRDSSAM also needs to increase the traction force and the stability of the WDR in the open hole well. Kinematic simulation numerical models of both conventional support adjustment mechanism and the DPRDSSAM are established. The two models comprehensively considere the influence of different obstacle forms and sizes on the obstacle surmounting performance of the tractor. The influence of different obstacle forms on the obstacle surmounting performance of DPRDSSAM and single push rod support adjustment mechanism (SPRSAM) is analyzed. Results show that the DPRDSSAM has better obstacle surmounting performance than the SPRSAM. The DPRDSSAM can effectively promote further research and application of the tractor in the open hole well.