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Anybody knows that contamination in oil is always harmful to hydraulic and lubricating systems. Contaminants inevitably exist in the oils of hydraulic and lubrication systems and cause tribological problems. In order to prevent such tribological problems due to contaminants, various oil cleaners have been developed and applied to hydraulic and lubricating systems. They have greatly contributed to improving the reliability of the systems. Since sophisticated hydraulic systems with proportional valves or servo valves, which are sensitive to oil contamination, became popular, fine filters like 3 micron or 1 micron are additionally used. However contamination problems have been revived. The authors have investigated the causes of hydraulic and lubricating problems and found that polymerized oil oxidation products were as harmful as solid particles. They are of molecular size and cannot be removed by mechanical filtration.

The reduction of particulate emissions from diesel engines is one of the most challenging problems associated with the exhaust air pollution control. Particulate emissions can be controlled by the adjustments of the combustion parameters of a diesel engine but these measures result in increased emissions of oxides of Nitrogen.Diesel particulate Filters (DPF) hold out the prospects of substantially reducing regulated particulate emissions but the question of the reliable regeneration of filters still remains a difficult hurdle. Many of the solutions proposed to date suffer from high engineering complexity, cost, thermal cracking, increased backpressure which in turn deteriorates diesel engine combustion performance. This paper presents an improved computer aided analytical approach for controlling Diesel soot particulate emission by Cyclone separator. Reduction of soot particles in the exhaust in turn reduces the Diesel Particulate Matter formation.

The design and development of a new four-stroke two-cylinder diesel engine family of 1.29 litre capacity for off road are discussed. The engine is in naturally aspirated and turbocharged and intercooled versions and rated from 11.9 kW/1500 rpm to 25.7 kW/2500 rpm. The engines were tuned for air and fuel flows, air utilisation, fuel air mixing, performance and emissions at steady state at a development lab and later certified in national labs. The high altitude capability of the TCIC was checked using a model. The engines rated at less than 19 kW satisfy India Generator set and off road norms of India and Europe equivalent to USTier4 standard, and at higher ratings, standard equivalent to US Tier4-interim. In the second part of the paper, the design of coolant and oil pumps, oil cooler for TCIC engine and the piston with steel oil control ring are discussed. The higher loaded TCIC engines use fillet hardened crankshafts of chromium molybdenum steel.

The earth's fossil energy is not limitless, and we should be taking advantage of the highly developed fields of science and technology to utilize it more efficiently and to create a fully environmentally friendly life. Considering the prodigious amount of vehicles in the world today, even a small improvement in their energy-saving performance could have a significant impact. In this paper, a new type of electro-hydraulic power steering (EHPS) system is described. It has two main advantages. First, it can significantly decrease the demand on the motor so that it can be used for a wider range of vehicles. Second, its pressure-flow characteristic can be programmed and is more flexible than hydraulic power steering (HPS) system. A prototype with a 500 W motor was applied to a truck with a front load of 2,700 kg, and static steer sweep tests were conducted to validate its feasibility.

The performance of five positive k-factor injector tips has been assessed in this work by analyzing a comprehensive set of injected mass, momentum, and spray measurements. Using high speed shadowgraphs of the injected diesel plumes, the sensitivities of measured vapor penetration and dispersion to injection pressure (100-250MPa) and ambient density (20-52 kg/m3) have been compared with the Naber-Siebers empirical spray model to gain understanding of second order effects of orifice diameter. Varying in size from 137 to 353μm, the orifice diameters and corresponding injector tips are appropriate for a relatively wide range of engine cylinder sizes (from 0.5 to 5L). In this regime, decreasing the orifice exit diameter was found to reduce spray penetration sensitivity to differential injection pressure. The cone angle and k-factored orifice exit diameter were found to be uncorrelated.

Measurement of emissions from small utility engines has usually been accomplished using steady-state raw emissions procedures such as SAE Recommended Practice J1088. While raw exhaust measurements have the advantage of producing modal exhaust gas concentration data for design feedback; they are laborious, may influence both engine performance and the emissions themselves, and have no provision for concurrent particulate measurements. It is time to consider a full-dilution procedure similar in principle to automotive and heavy-duty on-highway emission measurement practice, leading to improvements in many of the areas noted above, and generally to much higher confidence in data obtained. When certification and audit of small engine emissions become a reality, a brief dilute exhaust procedure generating only the necessary data will be a tremendous advantage to both manufacturers and regulatory agencies.

The vehicle overload seriously jeopardizes traffic safety and affects traffic efficiency. At present, the static weighing station and weigh-in-motion station are both relatively fixed, so the detection efficiency is not high and the traffic efficiency is affected; the on-board dynamic weighing equipment is difficult to be popularized because of the problem of being deliberately damaged or not accepted by the purchaser. This paper proposes an efficient, accurate, non-contact vehicle overload identification method which can keep the road unimpeded. The method can detect the vehicle overload by the relative distance (as the characteristic distance) between the dynamic vehicle's marking line and the road surface. First, the dynamics model of the vehicle suspension is set up. Then, the dynamic characteristic distance of the traffic vehicle is detected from the image acquired by the calibrated camera based on computer vision and image recognition technology.

A software using the Finite Element Method for machine-soil system was developed with the following features: (1) an iterative increment algorithm for solving dynamic problems with material non-linearity; (2) five strategies for reducing program running time; (3) strategies to utilize the computer memory resources under DOS environment; (4) a complete macro-command system; and (5) an advanced element-library managing structure.

Underwater bulldozers have been built for development of the ocean floor. Yet it is impractical for a diver to operate an underwater bulldozer from within the vehicle. Remote control of a bulldozer is extremely difficult due to complicated relationships between vehicle inclination, blade cylinder deflection, and the terrain profile in front of the bulldozer. In this paper a nonlinear automatic feedback blade control system is designed to replace direct operator control of the blade. To accomplish this design, mathematical models were developed for the vehicle dynamics and the hydraulic system dynamics of a typical bulldozer. Since both subsystem models are complicated nonlinear ones, the blade control system was designed using only a simplified hydraulic system model. The performance of the complete nonlinear system with the blade feedback control system added was then investigated using a hybrid computer simulation compared to available experimental data using a skilled operator.

A farm tractor protection cab made of thin steel sheet pressings is described. The cab is designed and produced using entirely automotive-type procedures. Curved glasses and a dampening suspension of the glasses are found to be an important means of achieving a low noise level in the cab. Using the pressing technique when producing a steel cab makes it possible to give the various cab details rigidity with a minimum of material. When welded together, these details form a very stiff cab body, which gives the necessary mechanical strength. The curved surfaces, the radii, and the round forms, which from a tooling point of view are natural for pressed steel parts, also have a vibration-dampening effect on the entire cab construction, thus making it easier to design a quiet tractor cab. Mounted on a farm tractor of conventional design, the cab meets the noise rating number ISO N85.

Today’s growing commercial vehicle population creates a demand for fossil fuel surplus requirement and develops highly polluted urban cities in the world. Hence addressing both factors is very much essential. Battery electric vehicles are with limited vehicle range and higher charging time. So it is not suitable for the long-haul application. In further the hydrogen fuel cell-based electric vehicles are the future of the commercial electric vehicle to achieve long-range, zero-emission and alternate for reducing fossil fuels requirement. The hydrogen fuel cell electric vehicle range, it means the total distance covered by the vehicle in a single filling of hydrogen into the onboard cylinders. And here the prediction of the vehicle range is essential based on optimal parameters; vehicle acceleration, speed, trip time etc. before the start of the trip.

Currently, Hardware-In-the-Loop (HIL) testing is the defacto standard for ECU verification and validation at the majority of the Commercial Vehicle OEMs and Tier1 suppliers. HIL Testing is used to shorten development and testing time for both engine and machine control systems. In order to use this process, many of these companies have to develop and maintain expertise in the area of Model-based development (MBD). This paper introduces an approach which allows for the effective use of HIL systems without having to directly work in a MBD environment. Many HIL tests can be done with stimulus and response analysis of the ECUs, given core knowledge of the expected behavior of its control software and I/O subsystems. For hardware interface and diagnostics validation, this open-loop testing of the controller may suffice. It is important to provide the tester with capabilities to easily modify these stimuli and evaluate the responses.

As a critical technology for autonomous vehicles, high precise positioning is essential for automated container terminals to implement intelligent dispatching and to improve container transport efficiency. Because of the unstable performance of global positioning system (GPS) in some circumstances, an ultra wide band (UWB) positioning system is developed for autonomous trucks in an automated container terminal. In this paper, an asynchronous structure is adopted in the system, and a three-dimensional (3D) localization method is proposed. Other than a traditional UWB positioning system with a server, in this asynchronous system, positions are calculated in the vehicle. Therefore, propagation delays from the server to vehicles are eliminated, and the real-time performance can be significantly improved. Traditional 3D localization methods based on time difference of arrival (TDOA) are mostly invalid with anchors in the same plane.

Gear tooth friction directly influences power losses and temperature rise as well as system dynamic behavior. Recently it attracted many attentions as friction is considered one of the main sources of power losses in geared systems, such as in automotive transmissions. Coefficient of friction has been found not a constant but varies with different contact conditions, which partly makes the measurement of friction a difficult and expensive process. Therefore an analytical model that is capable of predicting it accurately becomes very much demanded. A few empirical formulae based on experimental data and analytical models based on lubrication theory are found in the literature. However, they are either not suitable for a general gear contact or too complex to adapt in gearing. In this paper, a new coefficient of sliding friction based on a thermal Elastohydrodynamic Lubrication (EHL) model is developed by a multiple linear regression analysis.

In this paper, we proposed a novel integrated vehicle chassis control configuration, which is based on the combination of vehicle vertical and lateral motion controls. Focusing on the improvement of vehicle handling and riding performance, particularly the active safety under critical driving condition, the purpose of Active Suspension (AS) in the integrated system is to achieve ride comfort quality and to provide more tyre cornering ability near the cornering force saturation regions, while the effect of Four Wheel Steering (4WS) is expected to eliminate the body side slip angle and to achieve an ideal yaw rate model following.

As long as a tire steers about a titled kingpin pivot, the point coming in contact with the road moves along its perimeter. This movement affects the determination of kingpin moments caused by the tire forces, especially for large steering angles. The movement, however, has been neglected in the literature on the steerable-tire-kinematics-related topics. In this investigation, the homogeneous transformation is employed to develop a kinematic model of a steering tire in which the instantaneous ground-contact point on the tire is considered. The moments about the kingpin axis caused by tire forces are then computed based on the kinematics. A four-wheel-car model is constructed for determining the kingpin moment of steering system during the low-speed cornering maneuver. The result shows that the displacement of the ground-contact point along the tire perimeter is significant for large steering angles.

Reliability research in hybrid ceramic bearings involves life testing of hybrid bearings and ceramic specimens. New materials for bearings like advanced ceramics have emerged for evaluation in recent years. In fatigue testing to determine the stress-life relationship, the number of sample size in life testing can be limited by consideration of cost and testing time. In the testing of ceramics, some researchers have relied on the use of a stepwise multiple loading approach to increase the failure data points. In this paper, a maximum likelihood method is applied to test data with multiple loads to estimate the stress-life exponent. This method treats the data at different loads or steps at once. Test data from three fatigue experiments using silicon nitride materials have been analyzed to obtain the stress-life exponents. Also, Weibull plots of the ‘equivalent lives' have been presented for all test specimens tested at different loads and load steps.

Laser scanners are typically used in vehicle accident reconstruction and forensic applications to measure roadway and vehicle details. However, laser scanners used near congested roadways can digitize unwanted passing vehicles, which produces a scan with noisy and poor image quality point clouds. On the other hand, small Unmanned Aircraft System (sUAS) images of reflective objects may result in a less accurate mesh, and capturing vertical surfaces such as telephone poles, traffic lights, and building faces is more difficult. Prior research has tested the accuracy of sUAS-captured images processed with commercially available software, such as AgiSoft or Pix4D, as well as in comparison to the accuracy of laser scan data. Research still has yet to be conducted on combining the laser scans and sUAS images for use in accident reconstruction and other forensic settings.

Most vehicles designed primarily for off-road use - whether for the SUV, military, agricultural or earthmoving industries - employ all wheel drive systems. For off-road conditions where the traction is limited by the deformable nature of the ground, for example, loose track, soil or sand, providing a drive torque to all the wheels is the obvious design solution for maximising the total tractive effort. For military or commercial vehicles, this results in optimum mobility in difficult terrain, whereas for agricultural or earthmoving vehicles it often results in optimum work rates. In order to analyse the performance of off-road vehicles, it is necessary to understand the torque and power flows through the driveline system to each axle or wheel. The research presented in this paper focuses on the use of novel, non-contact torque sensors to measure the driveline torque distribution.

A revolution in mobile hydraulic equipment is occurring. Conventional hydraulic spool valves with hydromechanical pressure compensators are being replaced by valve assemblies with four valve independent metering with electronically-controlled pressure compensation. In the system described here, two of the four independent valves are active during metering. This new topology offers significant advantages due to the two degrees of freedom provided. In this paper, the theory behind a new method of flow control based upon load feedback is presented for two of the five distinct metering modes. In addition, a new algorithm for setting the supply pressure is presented which is also based upon load feedback.