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This paper deals with a conceptual aircraft cargo loader “that can do everything” commonly referred to as The Super Loader. The Super Loader is intended for use at air terminals to transport loads such as palletized cargo, containers, wheeled vehicles, shelters, and airdrop platforms from the storage docks to the military and civil aircraft, and vice versa. The loader may be described as a self-propelled, air transportable (in a C-141, C-17, C-5) 60,000 lb lifting capacity, adjustable height vehicle that will load/off load all transport aircraft from a C-130 whose cargo deck is only 3 feet, 3 inches high to a B-747 whose main deck upper limit is about 18 feet high. The Super Loader must also service the lower lobes of wide-bodies and main decks of narrow-bodied aircraft like the DC-8 and B-707. In brief, this loader will be required to interface with both civil and military cargo systems, present and future.

Nitrites have long been added to heavy-duty coolant to inhibit iron cylinder liner corrosion initiated by cavitation. However, in heavy-duty use, nitrites deplete from the coolant, which then must be refortified using supplemental coolant additives (SCA's). Recently, carboxylates have also been found to provide excellent cylinder liner protection in heavy-duty application. Unlike nitrites, carboxylate inhibitors deplete slowly and thus do not require continual refortification with SCA's. In the present paper laboratory aging experiments shed light on the mechanism of cylinder liner protection by these inhibitors. The performance of carboxylates, nitrites and mixtures of the two inhibitors are compared. Results correlate well with previously published fleet data. Specifically, rapid nitrite and slow carboxylate depletion are observed. More importantly, when nitrite and carboxylates are used in combination, nitrite depletion is repressed while carboxylates deplete at a very slow rate.

The automotive industry is dramatically changing. Many automotive Original Equipment Manufacturers (OEMs) proposed new prototype models or concept vehicles to promote a green vehicle image. Non-traditional players bring many latest technologies in the Information Technology (IT) industry to the automotive industry. Typical vehicle’s characteristics became wider compared to those of vehicles a decade ago, and they include not only a driving range, mileage per gallon and acceleration rating, but also many features adopted in the IT industry, such as usability, connectivity, vehicle software upgrade capability and backward compatibility. Consumers expect the latest technology features in vehicles as they enjoy in using digital applications in laptops and mobile phones. These features create a huge challenge for a design of a new vehicle, especially for a human-machine-interface (HMI) system.

China has become the world’s largest vehicle market in terms of sales volume. Automobiles sales keep growing in recent years despite the declining economic growth rate. Due to the increasing attention given to the environmental impact, more stringent emission regulations are being drafted to control traditional internal combustion engine emissions. In order to reduce vehicle emissions, environmentally-friendly new-energy vehicles, such as electric vehicles and plug-in hybrid vehicles, are being promoted by government policies. The Chinese government plans to boost sales of new-energy cars to account for about five percent of China’s total vehicle sales. It is well known that more electric and electronic components will be integrated into a vehicle platform during vehicle electrification.

Catalytic converters have become a viable aftertreatment system for reducing emissions from on-highway diesel engines. This paper addresses the development and production qualification of a catalytic converter. The testing programs that were utilized to qualify the converter system for production included emissions performance, emissions durability, physical durability, and field test programs. This paper reports on the specific tests that were utilized for the emissions performance and emissions durability testing programs. An explanation on the development of an accelerated durability test program is also included. The physical durability section of the paper discusses the development and execution of laboratory bench tests to insure the catalytic converter/muffler maintains acceptable physical integrity.

This study applies the methodology developed for two earlier evaluations of diesel particulate controls to urban buses. Since these vehicles are used almost exclusively in urban areas where population is most dense, the analysis indicates the net benefits of control are very high.

Typical design challenges for Unmanned Aerial Vehicles (UAVs) require low aerodynamic drag and structural weight. Both of these requirements imply that these aircraft are considerably more flexible than conventional aircraft and their stability analyses are more complex since they require models unifying rigid body and elastic dynamics. This paper aims to built such a model for a generic UAV. The model is then used to address stability in terms of divergence and flutter.

Fluid power systems are widely used in agricultural and construction equipment for power conversion and transmission. Solving dynamic stability problems associated with complex and inherently nonlinear fluid power systems on this equipment is very challenging. In the past ten years, a new technology named SNAS (Symbolic/Numeric Analysis/Synthesis) has been developed and implemented by the author (Jiao Zhang). SNAS has been successfully applied to fluid power engineering area for optimizing system dynamic performance. In this paper the fundamentals of SNAS will be discussed and the successful application of SNAS to solve a hydrostatic drive instability problem will be presented.

A hybrid electric vehicle simulation tool (IBZ-Simulator) has been developed at the Fuel Cell Institute of the University of Applied Sciences Esslingen to study the fuel economy potential of a Fuel Cell hybrid urban bus. In this paper, the fundamental architecture of the FC urban buses was described, as well as the control strategy to manage the power flow between the different elements of the drive train. A comparison of the hybrid with the conventional type and ICE-hybrid type is performed, and important factors relating to the vehicle efficiency (accessory loads, vehicle mass, Fuel Cell system ramping rate and battery capacity) were assessed. The using of supercapacitor (or ultracapacitors) as peak power buffer has been investigated.

The E-35 “Running Loss” program was planned in the fall of 1996, and conducted in the summer of 1997, as the third part of a series of Coordinating Research Council (CRC) sponsored evaporative emission test programs. One hundred and fifty vehicles (half cars - half light duty trucks) were recruited at a local I/M lane, and tested for running loss emissions at the ATL Facility in Mesa, AZ. The previous CRC programs had studied hot soak, and then diurnal emissions. Running loss emissions were measured in a Running Loss SHED (RL-SHED) for a 25 minute, 7.5 mile trip on a hot summer day (95°F). Vehicles from model years 1971 through 1991 were tested. A wide range in emission levels was observed - from a low of 0.13 g/mile to 43 g/mile. The test results were not able to establish whether car emissions are different, or the same, as light duty trucks. The major causes of the high emissions were liquid leaks on carburetor equipped models.

A unique system would solve traffic, fossil-fuel depletion, and environmental problems. Dual-mode private and commercial vehicles would be manually driven on streets and automatically controlled on maglev guideways. Busses and freight vehicles without wheels or drivers also used. Proposed guideway speeds: 100kph in cities, and 325kph between cities. System would be safer and have much higher capacity than existing highways or proposed “smart car” systems. One-third meter clearance between cars to be achieved by linear synchronous-motor propulsion. Capacity of single 100kph guideway to equal that of twelve highway lanes, and one 325kph guideway would be equivalent to forty highway lanes.

The need to accurately measure and record the payload of large off-highway mining trucks was identified by The Broken Hill Proprietary Co. Ltd. (BHP). In response. Caterpillar designed and developed a system to fufill that need. The payload carried by mine haul trucks has a strong influence on production rates and costs. The system developed should enable payloads to be much better controlled than has been previously possible. The system also provides a number of mine management features. The development of the system is described from the concept stage to the production stage. Final production capabilities of the microprocessor based system are described. Payload measurement capabilities, diagnostic capabilities, data storage, and data extraction methods are discussed.

The objective of this project was to model and study the interior noise in an Off-Highway Truck cab using Statistical Energy Analysis (SEA). The analysis was performed using two different modeling techniques. In the first method, the structural members of the cab were modeled along with the panels and the interior cavity. In the second method, the structural members were not modeled and only the acoustic cavity and panels were modeled. Comparison was done between the model with structural members and without structural members to evaluate the necessity of modeling the structure. Correlation between model prediction of interior sound pressure and test data was performed for eight different load conditions. Power contribution analysis was performed to find dominant paths and 1/3rd octave band frequencies.

Smaller locomotives often use mechanical transmissions instead of diesel-electric drive systems typically used in larger locomotives. This paper discusses how Model Based Design was used to develop the complete drive train control system for a 24 ton sugar cane locomotive. A complete MATLAB Simulink machine model was built to fully test and verify the shift control logic, traction control, vehicle speed limiting, and braking control for this locomotive application before it was commissioned. The model included the engine, torque converter, planetary transmission, drive line, and steel on steel driving surface. Simulation was used to debug all control code and test and refine control strategies so that the initial field commissioning in remote Australia was executed very quickly with minimal engineering support required.

With the rapid development of artificial intelligence, autonomous driving technology will finally reshape an automotive industry. Although fully autonomous cars are not commercially available to common consumers at this stage, partially autonomous vehicles, which are defined as level 2 and level 3 autonomous vehicles by SAE J3016 standard, are widely tested by automakers and researchers. A typical Human-Machine-Interface (HMI) for a vehicle takes a form to support a human domination role. Although modern driving assistance systems allow vehicles to take over control at certain scenarios, the typical human-machine-interface has not changed dramatically for a long time. With deep learning neural network technologies penetrating into automotive applications, multi-modal communications between a driver and a vehicle can be enabled by a cost-effective solution.

Gear rattle, clunk, and other such noises, commonly referred to as impulsive or unusual noise, are often classified as unique problems without common origins. This paper examines the underlying structure that promotes them and traces physical system behaviors that predispose them to such noises. Though the audible noise itself is not modeled directly, a good deal of the disposable energy that sustains it can be inferred from the impulsive dynamics that underlies the whole process. Further effort quantifies the energies involved and appraises the distinctiveness of the perceived noise. Whether one hears gear rattle or clunk depends on the initiating site within the system and the impulsivity index of the prevailing dynamics. Observable indicators suggest that periodic noise is supported by periodic dynamics and, similarly, impulsive noise, by impulsive dynamics and that the latter is non-deterministic, discontinuous and even chaotic.

The continued availability of leaded specialty aviation gasolines remains as an item of crucial importance in the near-term future of general aviation; however, the development of new piston engines capable of operation with other transportation fuels available in large pools is considered an indispensable element in the long-range survival of the industry. This paper offers a road map that while allowing the continued utilization of the current fleet of piston aircraft, sets the stage for a transition to new piston powerplants and associated aircraft, compatible with widely available transportation fuels such as motor gasoline based aviation fuels for the lower and some medium performance aircraft, and aviation turbine fuels for the balance of medium and high performance airplanes.

Lubricating oil affects the performance of friction materials in transmission, steering and brake systems. The TO-2 Test measured friction retention characteristics of lubricating oils used with sintered bronze friction discs. This paper introduces a new friction performance test for drive train lubricants that will be used to support Caterpillar's new transmission and drive train fluid requirements, TO-4, which measures static and dynamic friction, wear, and energy capacity for six friction materials, and replaces the TO-2 test. The new test device to be introduced is an oil cooled, single-faced clutch in the Link Engineering Co. M1158 Oil/Friction Test Machine.

A three dimensional mathematical model of a Caterpillar mining truck has been developed to simulate transient structural deformation and suspension response of a large mining truck traversing a known rough terrain course. The model incorporates compliant (finite element) representations of the truck frame, dump body, and rear axle housing into a dynamic mechanical system simulation model. Model results - frame acceleration, axle housing elastic deformation, and suspension response (strut pressures and displacements) are correlated with measured data from an instrumented truck traversing the steel speed bump portion of the rough terrain course. Results demonstrate that complex truck behavior can be simulated by combining finite element and mechanical system simulations.

Field testing of an extended life coolant technology in Class 8 trucks, equipped with Caterpillar C-12 engines revealed excellent coolant life with negligible inhibitor depletion to 400,000 miles with no refortification and no coolant top-off. In separate evaluations in Caterpillar 3406E equipped trucks, extended corrosion protection and component durability were established out to 700,000 miles, without the need for refortification other than top-off.