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An all-hydrostatic, track-driven vehicle with both remote control and autonomous operation capabilities was designed. The platform vehicle features fully hydrostatic drive with a variable displacement pump and a hub motor for each track. The combination of hydrostatic drive and tracks offers excellent controllability for autonomous applications as well as good maneuverability and traction. The remote control system allows the user to operate both the vehicle and various payloads, including robotic manipulators and surveillance equipment. The teleoperation (video-assisted remote control) has the same basic functionality, but allows the operator to be beyond visual range from the vehicle. The autonomous control system includes an easy-to-use man-machine interface and mission planning module, precise positioning, and autonomous controls for both the vehicle and the payload. The system design is modular and adaptable.

The design and employment of teleoperated heavy equipment for safe and efficient handling of hazardous material requires a thorough understanding of task characteristics and variables which can effect operator performance. This is particularly true when accurate end effector positioning is required, and where mistakes can result in life threatening events. This paper presents results of a Lockheed Martin Environmental Systems and Technologies Company Independent Research and Development study to determine the effects of 2-D vs 3-D visual displays on operator-system performance during a set of tasks associated with the operation of a 110,000 pound Caterpillar 235 Front Shovel. The research program is in support of Department of Energy, Department of Defense, Bureau of Mines, and Lockheed Martin commercial program objectives.

An efficient after treatment technique is driven by the need to maintain strict emission norms for heavy-duty and medium-duty ground vehicles. SCR being an advanced active emission technology system for diesel engine, is one of the most cost-effective and fuel-efficient technologies available for complying with the stringent NOx emission legislations. The design of the SCR system involves catalyst selection, complex controller development like urea dosing strategy and the interaction between engine setup and after treatment system. For this purpose, the SCR model must be computationally efficient to evaluate the complete efficiency along with to take care for the NH3 slip also. The SCR model was prepared with respect to SCR inlet temperature and ratio of NOx and ammonia to study the behavior of NOx conversion efficiency keeping consideration of NH3 slip also required for optimizing the calibration.

Based on the traditional heavy commercial vehicle, hydraulic hub-motor drive vehicle (HHMDV) is equipped with a hydraulic hub-motor auxiliary drive system, which makes the vehicle change from the rear-wheel drive to the four-wheel drive to improve the traction performance on low-adhesion road. In the typical operating mode of the vehicle, the leakage of the hydraulic system increases because of the oil temperature rising, this makes the control precision of the hydraulic system drop. Therefore, a temperature compensation control strategy for the assist mode is proposed in this paper. According to the principle of flow continuity, considering the loss of the system and the expected wheel speed, the control strategy of multifactor target pump displacement based on temperature compensation is derived. The control strategy is verified by the co-simulation platform of MATLAB/Simulink and AMESim.

Based on traditional heavy commercial vehicles, a hydraulic hub-motor drive vehicle (HHMDV) is equipped with a set of hydraulic hub-motor auxiliary system (HHMAS) to improve the traction performance and adaptability under complex conditions. In the case of low-speed operation or mechanical transmission failure, the creep mode (CM) can be used to drive the vehicle. Aiming at a common hydraulic system problem that flow loss increases due to temperature variation, a temperature compensation control strategy of the CM is proposed in this paper. By analyzing the speed regulation characteristics of the closed loop of the system in the CM, combined with the efficiency of the hydraulic variable pump (HP) and the hydraulic quantitative motor (HM), and aiming at adjusting the engine work in the optimal curve of the engine, the temperature compensation factor is introduced to control the HP displacement with hydraulic stepless speed regulation.

The nonuniformity property of the temperature field distribution will not only affect on the battery charging and discharging performance but also its lifetime. In this paper the elementary structural design is implemented for Ni-Mh battery package and the corresponding test platform is constructed from the point of view of temperature difference control strategy, the test results show that the present structural design schemes can effectively restrain temperature difference enlargement among the battery stacks. Through the application of adopting the flow field uniformity method to control temperature difference, and flow field optimization inside the battery package, it is found that the flow field velocity change quantity ΔV is gradually reduced as the increase of the afflux hood angle Ak and air vent width Da, and the difference of battery temperature is relatively lower, which denoting that the corresponding relationship can be created based on test data.

DATA presented in this paper show temperature-time diagrams obtained from mufflers mounted on trucks which were traveling over their regular routes. Using these temperature data, specimens made of possible muffler materials were subjected to laboratory tests. A wide range of possible muffler materials and gas composition were covered in these tests. Results of the tests indicate that under long-run heavy-duty truck service, muffler failure occurs primarily because of high metal temperatures and that coated mild steel showed the most promise of longer muffler life.

The air freight terminal has evolved from its beginnings as a by-product industry. It evolved like an unwanted child. The first terminals were patchwork copies of trucking terminals with modifications, but through many trials and errors, they have become the diverse, compatible, flexible series of systems that they are today. Air cargo terminals, even within the same system, are largely autonomous. This is as it should be. The terminals are individually keyed to the needs of their local shippers and their freight. Similarities exist, naturally, but the systems and the extent to which they are employed differ from station to station. Any attempt to impose uniform operating conditions on the various stations would impair their ability to respond to their local customers.

The dynamics of an AWD vehicle is determined by the interactions between the vehicle's wheels and the tire contact surface. Understanding and controlling these interactions drives the vehicle mobility and energy efficiency. In this paper new issues related to tire slippage control are addressed. The paper analytically demonstrates that two tires on the same axle with the same rotational speeds can have different slippages when the normal reaction and inflation pressure vary due to motion conditions. Hence, a new method is proposed to control the rotational velocity of the wheels in a way that provides the same slippages of the tires by accounting for changes in the normal load and tire inflation pressure. This approach is especially beneficial for vehicles with individual (electric) wheel drives which can be individually controlled by introducing the proposed algorithm for controlling both the vehicle linear velocity and the tire slippages.

This is an assessment of Japanese High Speed Surface Transport (HSST) policy, vision, goals, and magnetic levitation development and commercialization strategy. It includes a status report for a test program now underway to demonstrate the safety, reliability and economic viability of the HSST-100 maglev train system. HSST-100 is one of three types of HSST maglev trains planned for implementation in Japan: HSST-100 for 100 km/h urban service, HSST-200 for 200 km/h medium range suburban service, and HSST 300 for the 300 km/h long range interurban application. For the HSST-100 program, included are detailed specifications for the vehicle, location of the Chubu (Central Japan) test site South of Nagoya, test site guideway specifications, guideway switching concept, test site facility description, major test activities, and test event schedule.

This paper presents a recently developed method meant to act as a tool for objectively assessing and comparing the performance of automatic fire suppression systems. This methodology specifies requirements and procedures for evaluating the efficiency and performance of automatic fire suppression systems permanently installed in the engine compartments of buses and coaches. The testing is done according to SP method 4912 and carried out in a test enclosure where the fire performance of different suppression systems can be objectively assessed in a well-defined way. The test methodology includes a battery of fire tests simulating different engine loads, air flows and fire scenarios. Every tested system is rated according to its performance. The test method also includes testing of re-ignition due to hot surface ignition of liquid fuels.

In case of new generation of commercial vehicles, three shaft transmissions are designed with press fitted gears on counter shaft. It allows user to save the cost of transmission manufacturing by considerable amount. In case of heavy commercial vehicles, which are being used in abusive conditions such as mining and off-road applications, it becomes absolutely necessary to ensure that the gears press fit should withstand the continuous loads and impact loads. There are design guidelines available to ensure proper fit and torque carrying capacity between the mating parts. Still, there are gear slippage, shaft and gear breakage failures in the field. In this scenario, there is a need to develop bench test procedure which will capture such failures in the prototype stage. Looking at the failures in the field, it is necessary to capture all above hidden failures in design validation phase.

The commercialization of additives for treating internal combustion engine oils in Brazil was regulated by ANP Ordinance n° 131, from 30.7.1999 and revoked by ANP Resolution n° 10, from 07.03.2007, where requires the performance proof of the referred additive following the ASTM Sequence IIIF bench engine test. The test PB/IMI-1109S3FGM151-2 establishes a procedure to evaluate internal combustion engine oils as well as additives against special performance conditions particularly operating at high temperature based on ASTM D 6984-09 Sequence IIIF procedure. This test measures oil thickening, sludge and varnish formation in engine components, piston deposits, oil consumption and camshaft wear. The ASTM procedure also suggests the use of any engine that proves the competence to accelerate thermochemical deterioration of lubricants under severe operating conditions and temperature, allowing in that way the development of this test procedure.

In the years past, quite a number of relevant test procedures, including appropriate criteria of description, have been conceived to describe objectively the handling characteristics of passenger cars and passenger car-trailer combinations. Because of the various design principles of commercial vehicles and the ever-increasing advances of vehicle combinations insuring optimum utilization of space, i.e., single trucks or buses, truck-trailer combinations, semitrailer combinations, articulated buses, platform road trains, and short coupling truck combinations, the handling characteristics of these vehicles are definitely more distinct from each other. A description of the handling characteristics as compared with existing designs will be of great importance to the classification of new vehicle combinations. This paper gives a survey of the measuring procedures applied so far and the findings as published on the handling characteristics of heavy commercial vehicles.

Procedures for conducting full-scale coast down tests for the purpose of determining the aerodynamic drag forces on tractor-trailer trucks are presented. Tests were conducted on the baseline vehicle and on the baseline vehicle modified with drag reduction devices. Techniques for the evaluation of mechanical drag forces prior to the coast-down tests are given and a description of the instrumentation is included.

Networking is a need for interlinking todays and future electronic modules into systems. Networked systems offer reduced wiring harness, more open system expandability and an additional degree of freedom for system optimization. On the other hand networked systems represent highly complex problems for the system designers and therefore require correspondingly powerful tools. Subsequently the characteristics of networking are described based on the example of the CAN-network-protocol. A set of requirements for needed tool support is derived from the inherent networked system characteristics. A set of CAN network development tools is described - Simulator, Emulator, Analyzer, handy NetTest, PcNet-interface - supporting the various needs in the different design phases. Finally some future activities are described depicting tools enhancement and integration. In addition research activities are mentioned focusing on definition and evaluation of higher protocol layers.

The current focus in the ongoing development of autonomous driving systems (ADS) for heavy duty vehicles is that of vehicle operational safety. To this end, developers and researchers alike are working towards a complete understanding of the operating environments and conditions that autonomous vehicles are subject to during their mission. This understanding is critical to the testing and validation phases of the development of autonomous vehicles and allows for the identification of both the nominal and edge case scenarios encountered by these systems. Previous work by the authors saw the development of a comprehensive scenario generation framework to identify an operating domain specification (ODS), or external and internal conditions an autonomous driving system can expect to encounter on its mission to form critical scenario groups for autonomous vehicle testing and validating using statistical patterns, clustering, and correlation.

In order to test and design vehicle systems it is often necessary to develop prototypes. A vehicle's steering system requires a qualitative analysis since it is difficult to quantify and measure subjective quantities such as the “feel” of a steering system. The virtual prototype system (VPS) provides an effective and flexible way of developing and testing the prototypes for qualitative testing. By creating a computer model of a vehicle's steering system using a dynamic simulation package and linking it to a virtual reality vehicle, a designer can drive the virtual prototype vehicle as if he or she were operating an actual vehicle.

During the last years, DaimlerChrysler do Brasil (DCBR) has been moving ahead in order to research and to develop an Automatic Vehicular Location System (AVL System) due to the increase of the security through blocking and tracking devices, monitoring and mainly, logistic solutions that includes maintenance and fleet management. DaimlerChrysler do Brasil faced the necessity to prepare a test that could reflect a real situation, not only to try the system's features regardless communication and management of transmitted data, also however, to ensure the durability and reliability of the on-board vehicles equipment focusing on Brazilian Infrastructure. The objective of this paper is to describe the methodology, used tools and acquired results obtained by DCBR improvement test of his AVL System, throughout the “9o Rally Internacional dos Sertões - 2001”.