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An antipersonnel landmine neutralizing mechanism, called the Mine Hammer, was designed with a prototype developed by the Agriculture and Bioresource Engineering Department, University of Saskatchewan and Defence Research and Development Canada -- Suffield. The Mine Hammer technology combined flail mechanisms and agriculture tillage interaction mechanics. The prototype was retrofitted to be powered by a 78.4 kW tractor and was field evaluated in August 2002. The test plots represented gravel road, prairie clay soil with stubble and full stand of Kochia weed for vegetation and simulated tree stump terrains. Dummy or mechanical replicas of antipersonnel landmines were placed at 0, 25, 50, 100 and 200mm depths. The Mine Hammer triggered and/or fragmented the replica landmines. Its mechanical neutralization effectiveness over the five test plots was 97%. The Mine Hammer produced a two layer overburden consisting of a loose till above a dense, compact soil layer.

To provide good vehicle control in critical cornering, it is important to be able to sense the point of critical cornering. Even if the point of critical cornering is exceeded, it is possible to control the vehicle when drift control is good. As such, a compromise exists between the sensing of critical cornering and drift control. Experiments using a driving simulator were performed on different subjects to investigate this trade-off. It was found that the driver was able to sense the point of critical cornering easily from the change in body slip angle, and to control drift easily with a large body slip angle, in which the tire can attain a high cornering force. When the roll rigidity was low, however, drift control deteriorated although the sensing of critical cornering improved. Therefore, a moderate level of roll rigidity or roll rigidity control is desired to achieve a balance between these two factors.

The following has been understood for the change in the steer characteristic and the amount of perspiration in the drift cornering when not only visual information but also body sensory information is added. When body sensory information joins visual information as for the driver, it has been understood that the amount of perspiration increases overall and can do the drift control continuing with a moderate tension. In the drive only of visual information, the driver comes to arrive easily at spin because the drift control is difficult. And, it has been understood that the amount of perspiration increases greatly compared with the case to give body sensory information, and becomes the one with a very high risk. Moreover, the driver can control an adequate drift compared with driving only visual information in feed back body sensory information on the roll angle to the steer.

In this study, a compliant control strategy is developed, which makes the application of position based control strategies practicable for electric power assisted steering systems. In order to do this, an additional virtual degree of freedom is added to the system, which is stimulated by the torque exerted on the steering wheel by the driver and the pinion position. The electro-actuator modeled on the second pinion of the steering gear is then commanded to position the pinion to the virtual system position using a traditional position control strategy. Thus, a compliance behavior is established that can be varied depending on the vehicle states and environmental conditions to improve the vehicle dynamics and safety of the passenger.

The emerging business imperative of frequent new product introduction in market throws up challenge to shorten testing and evaluation time. Advanced test facilities and statistical tools have a greater role in reducing the evaluation cycle time. Considering limitations of field testing, a need was felt to simulate field condition in the laboratory i.e., ‘Bringing field to lab’. In this paper, an effort is made to explain the concept of ‘Bringing field to lab’ and the approach towards accomplishing it. The methodology developed for assessing effectiveness of laboratory tests i.e., ‘Power of Lab’ is shared. Various means of accelerating the tests and verifying field to lab correlation are explained. In quest to pursue the vision of ‘Bringing field to lab’ program, a new test facility has been developed to evaluate tractor i.e., Three-Poster Test System. Features of this test system, along with it’s role in ‘Bringing field to lab’, are shared along with the test results obtained.

A wind tunnel experiment has been conducted to determine the changes in drag and side force due to the presence and position of cab extenders on a model of a commercial tractor-trailer truck. The geometric variables investigated are the cab extenders angle of incidence, the tractor-trailer spacing and the yaw angle of the vehicle. Three cab extender angles were tested-0°, 15° (out) and -15° (in) with respect to the side of the tractor. The cab and trailer models have the same width and height. The minimum drag coefficient was found for the tractor and trailer combination when the cab extenders were set to 0° angle of incidence with respect to the headwind. This result holds for all yaw angles with moderate gap spacing between the tractor and trailer. This study suggests that commercial tractor-trailer trucks can benefit from adjustable cab extender settings; 0° when using a trailer and -15° when no trailer is used.

The RTV900 utility vehicle with tractor technology features the first Variable Hydro Transmission (VHT) with auxiliary hydraulics, power steering and wet disc brakes. The VHT comes equipped with a servo-type variable capacity pump, linked in parallel with fixed capacity and variable capacity motors on the same axle. This variable motor enables an increased driving force with auto-deceleration. Additionally, the RTV900 uses hydraulic power steering that is commonly used on tractors. The RTV900's power steering decreases heavy kickback in rough terrain and allows the operator to maneuver and drive the machine with minimal effort. Wet disk brakes resolve the problems of mud and water that can infect dry-type brakes, improving safety and reliability in bad road conditions. With its sealed VHT components, power steering and wet disk brakes, the RTV900 will provide farmers, vineyards, nurseries, orchards and golf courses increased power, lower maintenance costs and easy, safe operation.

The 4200 Hybrid Electric Vehicle is a Class 5-6 medium duty chassis usable in a variety of short range applications. The vision for this vehicle concept is a self contained hybrid diesel-electric vehicle with range and performance similar to a diesel-only vehicle along with improved fuel efficiency. The hydraulic steering system is an ideal candidate for energy savings due to its continuously running on-engine pump component. Electrically powered hydraulic steering (EPHS) pumps, along with a Column Drive electric assist unit, replace the conventional engine driven pump. The Column Drive masks any switching transients in the flow from the EPHS units and provides steering feel tuning. The system offers the benefits of improved on-center handling, increased returnability, speed proportional assist, and cross-wind compensation.

Renewed interest in a gas turbine as an alternative driveline for heavy trucks within Volvo, driven by the demands for lower emissions, resulted in a pre-study during 1990-1992 and the development and testing of a demonstrator engine between 1993 and 2000. To achieve the demanding goals for efficiency and emissions, the engine was designed as a recuperated and intercooled two shaft powerplant with a low-emission combustor. Following a comprehensive aerodynamic and concept study, engine components were rig tested and the engine mechanical design was finalized. Two engines were built and tested in a rig and in a truck. Very low exhaust emissions were demonstrated during rig testing, with NOx as low as 0,22 g/kWh in a 13-mode test. The efficiency goal of 42 % was not reached, but given more development time the measured efficiency of 38,6 % can most certainly be improved. Still, it will be the fuel consumption that is the major disadvantage compared to a diesel engine.

Overturning on a road turn has always been a problem in vehicles. Based on a half- vehicle model, the results of vehicle stability after incorporating a hydraulic-actuator system is analyzed. It has been shown in the paper that the stability of a vehicle on a road turn can be increased promisingly by tilting its body towards the inner direction. The results are compared with the corresponding results of a conventional vehicle. Because of the feasibility and effectiveness of the proposed algorithm, the above system shows a definite improvement in vehicle stability.

The handling quality of a car is one of the most crucial parameters in the evaluation of the vehicle's overall performance. This quality is noticeably influenced by the structural and functional characteristics of the various components of the vehicle. The vehicle platform subsystems (i.e. steering, suspension, and braking) have major role in altering and tuning handling quality. It brings up special concerns in designing each of these mechanisms and need of having a comprehend understanding of their role in the handling characteristics of a vehicle. In this article, a general method for the optimization of steering system is presented. The investigation is focused on the geometrical parameters of a rack and pinion steering system, and their contribution on the handling characteristics. This kind of steering is common in medium class vehicles.

Hardware-in-the-Loop (HWIL) testing is a means for validating and verifying component designs in a system context. Most current HWIL work with electrochemical systems for automotive applications has focused on the pack level, providing valuable feedback to system designers. Further benefits are realized by implementing this concept earlier in the development process; applying test vectors to an individual cell, but attenuating the stimulus and feedback to pack levels. This paper reports on a cell-level HWIL system designed to evaluate electrochemical cells and associated subsystems for advanced hybrid-electric vehicles (HEVs). The architecture of the system is described along with an example of its application applied to a commercially available supercapacitor and a state-of-charge algorithm in an HEV-based configuration.

The development of Steer-by-Wire (SbW) systems for on-road use is a challenging task. In a joint industry effort several companies have teamed up in the TTA-Group SbW Working Group to develop an architectural cookbook for SbW. The working group started with the development of a concept document. It adopts IEC 61508 for the development of a reference SbW architecture for on-road use. The main focus of the working group will be achieved in a second step where common parts of the electronic architecture will be developed.

For the purposes of on-line control, e.g., in an automatic driving system, or of closed-loop directional control simulation, an optimal preview artificial neural network (ANN) driver model based on error elimination algorithm(EEA) is built. Then the optimal preview times are discussed in high frequency range in this system. The simulation results of optimal preview ANN driver model and Error Elimination Algorithm driver model are compared under the condition of different vehicle speeds and paths, which shows that the proposed approach is efficient and reliable enough, particularly for driver-vehicle closed-loop system.

The National Research Council of Canada (NRC) is commencing a new round of aerodynamic development of heavy trucks in partnership with Natural Resources Canada (NRCan), the Canadian Trucking Alliance (CTA) and the US Department of Energy (DOE). The program is meant to take second-generation, add-on technology from the wind tunnel to the fleet. The purpose is to reduce fuel consumption and greenhouse gas emissions. The benefit is that the fuel reductions pay the operators to improve their vehicle emissions. 1:10-scale model tests in the NRC 2m × 3m wind tunnel, followed by full-scale tests on a Navistar 9200 Day Cab with 40-foot trailer in the NRC 9m × 9m wind tunnel, were employed to develop the add-on devices of interest. The results demonstrated significant fuel savings from a combination of longer cab extenders, trailer skirts and trailer boat-tails that reduced fuel consumption as much as the contemporary aerodynamic cab packages.

With rising oil prices, the issue of energy economy in transportation is getting much attention. At the same time, new emissions standards for tractor-trailer vehicles introduce additional challenges for the manufacturers to achieve improvements in vehicle fuel economy. As part of the U.S. Department of Energy Office of FreedomCAR and Vehicle Technologies' Heavy Vehicle Aerodynamic Drag Consortium, Argonne National Laboratory is currently developing guidelines for the use of commercial computational fluid dynamics (CFD) software to facilitate energy efficiency improvements through improved aerodynamic design of tractor-trailer vehicles. The development of these guidelines requires the consideration of the sensitivity of the accuracy of the analysis to the various modeling choices available to the end user.

At 70 miles per hour, overcoming aerodynamic drag represents about 65% of the total energy expenditure for a typical heavy truck vehicle. The goal of this US Department of Energy supported consortium is to establish a clear understanding of the drag producing flow phenomena. This is being accomplished through joint experiments and computations, leading to the intelligent design of drag reducing devices. This paper will describe our objective and approach, provide an overview of our efforts and accomplishments related to drag reduction devices, and offer a brief discussion of our future direction.

A Diesel Particulate Filter (DPF) is needed to meet the Particulate Matter (PM) requirements of US EPA 2007 regulations for diesel engines. A catalyzed diesel particulate filter (cDPF or CSF) in combination with a diesel oxidation catalyst (DOC) is effective if the DOC has achieved light-off. However, for some applications, exhaust temperature will be too low to achieve DOC light-off. Therefore a reliable active regeneration means will be required. This paper presents a diesel-fired filter regenerator that works with an uncoated DPF. During regeneration, the thermal regenerator raises the exhaust temperature to 650 °C at the filter face at any engine condition, including idle. The thermal regenerator was tested on a cordierite filter placed on a heavy-duty diesel engine with cooled-EGR (2007 calibrations). THC, CO and NOx emissions, as well as opacity, in the tailpipe were measured at both steady state and transient engine conditions.

Due to the large size, high bulk density and high thermal expansion coefficient of the diesel particulate filter substrate; the conventional mounting system cannot provide the necessary radial mounting pressure. Mathematical and experimental results give the vibration and the back pressure force needed to mount the diesel particulate filter in the exhaust system. L-seal mounting support used in diesel particulate filter provides cushion to accommodate the linear tolerance of the substrate and the cone and also the necessary axial and radial mounting forces. L-seal axial and radial mounting forces are altered by type of material, surface characteristics, heat treatment and wire geometry. The proportional increase in compression force per unit weight during cycling shows dimensional consistency of the L-seal. The compression characteristics of A286 tremendously increase (>20%) during heat treatment as precipitation and hardening occurs.

Knitted wiremesh along with radial gas tight seals provide reliable mounting system for low temperature underbody converters. The compression characteristics of the wiremesh is modified by wire material, wire diameter, wire geometry, mesh crimp heights; wire density, wiremesh courses per inch, needle count, number of strands, wiremesh temper, wiremesh surface profile and surface characteristics. The radial mounting pressure provided by the wiremesh is matched with the mounting pressure requirement. Wiremesh systems can be tailored to any required radial mounting pressure from conventional to ultra thin-wall substrates. The wiremesh mounting system is proven durable, without any failure on more than 25 million underbody converters in light duty vehicles. Cp and Cpk show the capability of the manufacturing process. Thus the wiremesh mounting support is a viable alternate for low temperature gasoline and diesel applications.