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The object of this paper is to present a new way of analyzing in-cylinder velocity measurements. The technique is called Discrete Wavelet Transform (DWT) and it is similar to Fast Fourier Transform (FFT) with one important difference it is possible to obtain both time localized and frequency resolved information. This paper demonstrates the use of DWT calculations on in-cylinder LDV flow measurements for different combustion geometries in a natural gas converted truck engine. It will furthermore provide some information about how DWT can be used with in-cylinder measurements in the future.

Heavy trucks contribute significantly to the overall air pollution, especially NOx and PM emissions. Models to predict the emissions from heavy trucks in real world on road conditions are therefore of great interest. Most such models are based on data achieved from stationary measurements, i.e. engine maps. This type of “quasi stationary” models could also be of interest in other applications where emission models of low complexity are desired, such as engine control and simulation and control of exhaust aftertreatment systems. In this paper, results from quasi stationary calculations of fuel consumption, CO, HC, NOx and PM emissions are compared with time resolved measurements of the corresponding quantities. Measurement data from three Euro 3-class engines is used. The differences are discussed in terms of the conditions during transients and correction models for quasi stationary calculations are presented. Simply using engine maps without transient correction is not sufficient.

While significant progress has been made in recent years to develop hybrid and battery electric vehicles for passenger car and light-duty applications to meet future fuel economy targets, the application of hybrid powertrains to heavy-duty truck applications has been very limited. The relatively lower energy and power density of batteries in comparison to diesel fuel and the operating profiles of most heavy-duty trucks, combine to make the application of hybrid powertrain for these applications more challenging. The high torque and power requirements of heavy-duty trucks over a long operating range, the majority of which is at constant cruise point, along with a high payback period, complexity, cost, weight and range anxiety, make the hybrid and battery electric solution less attractive than a conventional powertrain.

The main benefit of HCCI engines compared to SI engines is improved fuel economy. The drawback is the diluted combustion with a substantially smaller operating range if not some kind of supercharging is used. The reasons for the higher brake efficiency in HCCI engines can be summarized in lower pumping losses and higher thermodynamic efficiency, due to higher compression ratio and higher ratio of specific heats if air is used as dilution. In the low load operating range, where HCCI today is mainly used, other parameters as friction losses, and cooling losses have a large impact on the achieved brake efficiency. To initiate the auto ignition of the in-cylinder charge a certain temperature and pressure have to be reached for a specific fuel. In an engine with high in-cylinder cooling losses the initial charge temperature before compression has to be higher than on an engine with less heat transfer.

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.

The advancement in embedded systems and positional accuracy with base station GPS modules created opportunity to develop high performance autonomous ground vehicles. However, the development of vehicle model and making accurate state estimations play vital role in reducing the cross track error. The present research focus on developing Linear Quadratic Gaussian (LQG) with Kalman estimator for autonomous ground vehicle to track various routes, that are made with the series of waypoints. The model developed in the LQG controller is a kinematic bicycle model, which mimics 1/5th scale truck. Further, the cubic spline fit has been used to connect the waypoints and generate the continuous desired/target path. The testing and implementation has been done at APS labs, MTU on the mentioned vehicle to study the performance of controller. Python has been used for simulations, controller coding and interfacing the sensors with controller.

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.

Galvanic corrosion between die cast AZ91D and AM60B and different fastener systems has been evaluated by exposure on trucks and in accelerated laboratory tests. The exposure time on the trucks was 3 years, corresponding to a mileage of about 300000 km. Samples were retracted and evaluated after 1 and 2 years exposure. Similar samples were also exposed to the Volvo Indoor Corrosion Test and the General Motors GM9540P-cycle B test. The correlation between the field data and the laboratory tests was evaluated, as was the sharp difference in the performance of the fastener systems in the two accelerated laboratory tests.

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.

Electronics technology has evolved significantly since the first electronically controlled heavy duty on-highway truck engines were introduced in the mid 1980's. Engine control hardware, software, and sensor designs have been driven by many factors. Emissions regulations, fuel economy, engine performance, operator features, fleet management information, diagnostics, vehicle integration, reliability, and new electronics technology are some of those factors. The latest engine electronics technology is not only found in heavy duty on-highway trucks, but in off-highway applications as well. Track-type tractors, haul trucks, wheel loaders, and agricultural tractors now benefit from the advantages of electronic engines. And, many more new applications are being developed.

In-cylinder flow measurements, conventional swirl measurements and CFD-simulations have been performed and then compared. The engine studied is a single cylinder version of a Scania D12 that represents a modern heavy-duty truck size engine. Bowditch type optical access and flat piston is used. The cylinder head was also measured in a steady-flow impulse torque swirl meter. From the two-dimensional flow-field, which was measured in the interval from -200° ATDC to 65° ATDC at two different positions from the cylinder head, calculations of the vorticity, turbulence and swirl were made. A maximum in swirl occurs at about 50° before TDC while the maximum vorticity and turbulence occurs somewhat later during the compression stroke. The swirl centre is also seen moving around and it does not coincide with the geometrical centre of the cylinder. The simulated flow-field shows similar behaviour as that seen in the measurements.

The most economical way to convert truck and bus DI-diesel engines to natural gas operation is to replace the injector with a spark plug and modify the combustion chamber in the piston crown for spark ignition operation. The modification of the piston crown should give a geometry well suited for spark ignition operation with the original swirling inlet port. Ten different geometries were tried on a converted VOLVO TD102 engine and a remarkably large difference in the rate of combustion was noted between the chambers. To find an explanation for this difference a cycle resolved measurement of the in-cylinder mean velocity and turbulence was performed with Laser Doppler Velocimetry (LDV). The results show a high correlation between in cylinder turbulence and rate of heat release in the main part of combustion.

Catalytic converters have been developed to reduce diesel engine emissions to aid in meeting the 1994 EPA on-highway standards for heavy duty (above 8,500 pound gross vehicle weight) trucks. As converters are made available for on-highway applications, questions inevitably arise as to their applicability to larger off-highway equipment. This paper covers the application of catalytic converters to a Caterpillar 785 off-highway truck operating in a diamond mine in Siberia. Targeted emissions for this application were unburned hydrocarbons (HC) (especially aldehydes), and carbon monoxide (CO). Experience from the on-highway converter development indicated oxidation catalysts could reduce these emissions. This paper addresses the development and selection of a catalytic converter for the 785 truck. Tradeoffs of vehicle modifications vs. catalytic converter performance and design are discussed.

Autonomous vehicle operation is dependent upon accurate position estimation and thus a major concern of implementing the autonomous navigation is obtaining robust and accurate data from sensors. This is especially true, in case of Inertial Measurement Unit (IMU) sensor data. The IMU consists of a 3-axis gyro, 3-axis accelerometer, and 3-axis magnetometer. The IMU provides vehicle orientation in 3D space in terms of yaw, roll and pitch. Out of which, yaw is a major parameter to control the ground vehicle’s lateral position during navigation. The accelerometer is responsible for attitude (roll-pitch) estimates and magnetometer is responsible for yaw estimates. However, the magnetometer is prone to environmental magnetic disturbances which induce errors in the measurement.