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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.

Commercial vehicles carry more than 10 billion tons of goods - approximately 70 percent of all freight shipped and travel over 450 billion miles each year in the United States. These vehicles are the exclusive mode of delivery in over 75 percent of U.S. communities. Such utilization and dependency demand commercial vehicles be reliable, durable, and cost effective. The heart of these commercial vehicles (Classes 3-8) is the diesel engine. The widespread use of the diesel engine can be attributed to its reliability, durability, and cost effectiveness. However, the 2007 and 2010 EPA emissions regulations are creating significant challenges for diesel-powered commercial vehicles. Engine and vehicle manufacturers must strike a balance between emissions, performance, and affordability. A consequence of the evolution of the diesel engine to meet the increasingly stringent emissions regulations is that more effort to accommodate the associated changes is driven to the vehicle manufacturers.

This paper presents a compact temperature control device to cool down hot exhaust gas coming out of an aftertreatment emission control system. Active DPF (Diesel Particulate Filter) regeneration is required for aftertreatment emission controls to meet the 2007 EPA (Environmental Protection Agency) PM(Particulate Matter) standard. However, regeneration of the DPF temporarily elevates temperatures in the filter to eliminate accumulated soot. This can increase the temperature of the exhaust gas. The temperature control device in this paper draws ambient air into the hot exhaust stream and mixes them together in such a fashion to maximize temperature drop and minimize back pressure for a limited space without any moving parts or supply of extra power. The simple and compact design of the device makes it a cost-effective candidate to retrofit to an existing aftertreatment system.

The successful development of new products is contingent on clearly understanding product requirements and defining appropriate design activities to deliver the right product. Even if one can clearly understand the abstract requirements implied by the voice-of-customer (VOC), engineers still work best to a set of specifications that define the product in objective measures. The task of extracting the systems specifications from text versions of product requirements is not trivial. Full order dynamic models of mass, springs and dampers provide understanding of vehicle performance; however, the engineer has to define the dynamic characteristics based on his understanding of requirements and translate them into technical specifications. The result can be too dependent on human assumptions and judgments at this point. This work was done to understand how to apply Object Oriented Design (OOD) methodology to trace requirements of a mechanical system to design parameters.

In the present work computational fluid dynamics (CFD) simulations of the flow field around a generic tractor-trailer truck are presented and compared with corresponding experimental measurements. A generic truck model was considered which is a detailed 1/8th scale replica of a Class-8 tractor-trailer truck. It contained a number of details such as bumpers, underbody, tractor chassis, wheels, and axles. CFD simulations were conducted with wind incident on the vehicle at 0 and 6 degree yaw. Two different meshing strategies (tet-dominant and hex-dominant) and three different turbulence models (Realizable k-ε, RNG k-ε, and DES) are considered. In the first meshing strategy an unstructured tetrahedral mesh was created over a large region surrounding the vehicle and in its wake. In the second strategy the mesh was predominantly hexahedral except for a few narrow regions around the front end and the underbody which were meshed with tetrahedral cells owing to complex topology.

A droplet deformation and rotation model (DDR) has been developed and implemented in the KIVA II CFD code for better describing characteristics of liquid fuel sprays in diesel engines, including the distribution of sprays in combustion chamber space and the spray/wall impingement. The DDR model accounts for the effects of both the droplet's frontal area and its drag coefficient as a function of its deformation and rotation on droplet drag and droplet breakup. Therefore, the DDR model can be used for calculating the fuel droplet's drag and breakup in the process of combustion in diesel engines. This makes it possible to model the highly distorted droplet's frontal area variation and its effect on the drag coefficient in sprays. The new version of the KIVA II code with the DDR model has been tested for a case of the spray/wall impingement and a case of the combustion process in a diesel engine.

The effects of an oxidation catalytic converter (OCC), an emulsified fuel, and their combined effects on particle number and volume concentrations compared to those obtained when using a basefuel were studied. Particle size and particulate emission measurements were conducted at three operating conditions; idle (850 rpm, 35 Nm), Mode 11 (1900 rpm, 277 Nm) and Mode 9 (1900 rpm, 831 Nm) of the EPA 13 mode cycle. The individual effects of the emulsified fuel and the OCC as well as their combined effects on particle number and volume concentrations were studied at two different particle size ranges; the nuclei (less than or equal to 50 nm) and accumulation (greater than 50 nm) modes. An OCC loaded with 10 g/ft3 platinum metal (OCC1) and a 20% emulsified fuel were used for this study and a notable influence on the particle size with respect to number and volume distributions was observed.

A study was conducted to assess the effects of a water-diesel fuel emulsion with and without an oxidation catalytic converter (OCC) on steady-state heavy-duty diesel engine emissions. Two OCCs with different metal loading levels were used in this study. A 1988 Cummins L10-300 heavy-duty diesel engine was operated at the rated speed of 1900 rpm and at 75% and 25% load conditions (EPA modes 9 and 11 respectively) of the 13 mode steady-state test as well as at idle. Raw exhaust emissions' measurements included total hydrocarbons (HC), oxides of nitrogen (NOx) and nitric oxide (NO). Diluted exhaust measurements included total particulate matter (TPM) and its primary constituents, the soluble organic (SOF), sulfate (SO42-) and the carbonaceous solids (SOL) fractions. Vapor phase organic compounds (XOC) were also analyzed. The SOF and XOC samples were analyzed for selected polynuclear aromatic hydrocarbons (PAHs).

In this paper, the conversion of a production SUV to a hybrid electric vehicle with a drive system utilizing a planetary power-split transmission is presented. The uniqueness of this design comes from its ability to couple the advantages of a parallel hybrid with the advantages of a series hybrid. Depending on operating conditions and recent operating history, the drive system transitions to one of several driving modes. The drive system consists of a planetary gear set coupled to an alternator, motor, and internal combustion engine. It performs the power-split operation without the need for belt drives or clutching devices. The effects on driveability, manufacturing, fuel economy, emissions, and performance are presented along with the design, selection, and implementation of all of the vehicle conversion components.

This paper discusses a practical use of the Systems Engineering Process as it is implemented in a Truck OEM. The process presented is focused on the Electrical and Electronics area, but can be applied to other systems on the vehicle and to the vehicle level requirements. Systems Engineering rationale is summarized based upon historical impacts and the application of Systems Engineering to address those impacts. Prior System Development Processes are reviewed in light of modern Systems Engineering approaches, leading to the synthesis of the Systems Engineering Documentation Set for the Vehicle and the Vehicle's Electrical and Electronic Systems. The analysis for this approach looks at the application of Systems Engineering Principles throughout the lifecycle of the vehicle, going beyond the boundaries of traditional requirements gathering and analysis.

This study was conducted to assess the effects of a low sulfur (<0.05 wt.%) fuel and an uncatalyzed ceramic particle trap on heavy-duty diesel emissions during both steady-state operation and during periods of electrically assisted trap regeneration. A Cummins LTA10-300 engine was operated at two steady-state modes with and without the trap. The exhaust trap system included a Corning EX-54 trap with an electrically assisted regeneration system. Both regulated emissions (oxides of nitrogen - NOx, total hydrocarbons - HC, and total particulate matter - TPM) and some unregulated emissions (polynuclear aromatic hydrocarbons - PAH soluble organic fraction - SOF, sulfates, vapor phase organics, and mutagenic activity) were measured during baseline, trap, and regeneration conditions. Emissions were collected with low sulfur (0.01 wt.%) fuel and compared to emissions with a conventional sulfur (0.32 wt.%) fuel. These fuels also varied in other fuel properties.

This paper describes how mind mapping software can help to visualize: System performance requirements Product attributes that satisfy performance requirements Mapping between performance requirements and product attributes An example is given using a partial model for vehicle performance developed by the International Truck and Engine Corporation. The mind map software used in this study is Mind Manager Pro version 6 by Mindjet. Anecdotal evidence is offered for the benefits and challenges of implementing a visual Mind Map scheme; however, the judgment of overall effectiveness is left to the reader.

The increased availability of natural gas (NG) in the United States (US) and its relatively low cost versus diesel fuel has increased interest in the conversion of medium duty (MD) and heavy duty (HD) engines to NG fueled combustion systems. The aim for development for these NG engines is to realize fuel cost savings and increase operating range while reduce harmful emissions and maintaining durability. Traditionally, port-fuel injection (PFI) or premixed NG spark-ignited (SI) combustion systems have been used for light duty LD, and MD engines with widespread use in the US and Europe [1]. However, this technology exhibits poor thermal efficiency and is load limited due to knock phenomenon that has prohibited its use for HD engines. Spark Ignited Direct Injection (SIDI) can be used to create a partially stratified combustion (PSC) mixture of NG and air during the compression stroke.

This paper discusses the evaluation and application of a portable parked-vehicle tailpipe emissions measurement apparatus (EMA). The EMA consists of an exhaust dilution system and a portable instrument package. The EMA instantaneously dilutes and cools a sample of exhaust with compressed nitrogen or air at a known dilution ratio, thereby presenting it to instruments as it is presented to personnel in the surrounding environment. The operating principles and governing equations of the EMA are presented. A computational method is presented to determine the engine operating and performance parameters from the exhaust CO2 concentrations along with an assumed engine overall volumetric efficiency and brake specific fuel consumption. The parameters determined are fuel/air ratio, mass flow rates of fuel, air and exhaust emissions, and engine brake torque and horsepower.

This research quantifies the effects of a copper fuel additive on the regulated [oxides of nitrogen (NOx), hydrocarbons (HC) and total particulate matter (TPM)] and unregulated emissions [soluble organic fraction (SOF), vapor phase organics (XOC), polynuclear aromatic hydrocarbons (PAH), nitro-PAH, particle size distributions and mutagenic activity] from a 1988 Cummins LTA10 diesel engine using a low sulfur fuel. The engine was operated at two steady state modes (EPA modes 9 and 11, which are 75 and 25% load at rated speed, respectively) and five additive levels (0, 15, 30, 60 and 100 ppm Cu by mass) with and without a ceramic trap. Measurements of PAH and mutagenic activity were limited to the 0, 30 and 60 ppm Cu levels. Data were also collected to assess the effect of the additive on regeneration temperature and duration. Copper species collected within the trap were identified and exhaust copper concentrations quantified.

This paper describes the electrical system development for the headlight feature in an International High Performance Vehicle. Systems engineers developed several iterations of functional requirements, functional block diagrams, state diagrams, and body controller software requirements early in the development cycle at considerable engineering expense. The hardware design team found the functional block diagrams useful, however the software design team did not find the other artifacts useful. The software design teams chose to implement a design that was very similar to a current product offering and did not map to the system proposed by the systems engineering team. This paper provides examples of the Systems Engineering artifacts and shows when they were developed in the project timeline.

This paper describes the results of experiments that were performed using a Ground Research Vehicle (GRV) at the National Aeronautics and Space Administration's (NASA) Dryden Flight Research Center in Edwards, CA and a comparison with computational results. The GRV is a modified 1984 General Motors (GMC) van and measures 40 feet long and 9 feet high, with a base area of 83 by 83, and it weighs 10260 lbs and holds a crew of up to three. Air data is measured from a nose-boom, 2 global positioning (GPS) units, and an absolute Honeywell Pressure Transducer with 4 Electronic Signal Processor (ESP) scanners and 64 surface pressure ports. This allows for detailed measurements of the surface pressure profiles around the vehicle. The total vehicle drag is estimated from coast-down tests, while the pressure component of the drag force may be calculated by integrating the pressure profiles on the front and base of the vehicle.

A review of mine air pollutant standards and the important pollutants to control in underground mines using diesel powered equipment is presented. The underground Mine Air Quality Laboratory instrumentation is discussed. This includes the Mine Air Monitoring Laboratory (MAML) and the instrumented Load Haul Dump (LHD) vehicle. The MAML measures CO, NO2, NO, CO2, particulate and temperatures while the LHD instrumentation measures and records engine speed, rack position (fuel rate), vehicle speed, CO2 concentration, exhaust temperature and operating mode with transducers and a Sea Data Corporation data logging and reader system. The mine LHD cycle data are related to the EPA 13 mode cycle data. Engine and aftertreatment emission control methods are reviewed including recent laboratory NO, NO2, sulfate and particulate data for a monolith catalyst. Maintenance of the LHD vehicle by engine subsystems in relation to component effects on emissions is presented.

The First Annual Blizzard Baja was hosted by Michigan Technological University's SAE Student Branch on February 7, 1981. This was a competition between student designed vehicles which had previously competed in summer Baja events. The Blizzard Baja consisted of a one hour endurance race run on ice and snow. The purpose was to provide the student engineers an opportunity to test their vehicles in cold weather, snow and icy conditions.

The effect of truck dieselization for three levels of diesel penetration into each of the eight classes of trucks is modeled. Diesel and total truck sales, population, mileage and yearly fuel usage data are aggregated by four truck classes representing light, medium, light-heavy and heavy-heavy classes. Four fuel economy scenario's for different technological improvements were studied. Improvement of fuel economy for light and heavy-heavy duty vehicle classes provides significant total fuel savings. Truck dieselization of light and light-heavy duty vehicle classes provides the largest improvement of fuel usage due to the fact that they have large numbers of vehicles and presently have few diesels. Total car and truck fuel usage in the 1980's shows roughly a constant demand with cars decreasing due to improved new fleet fuel economy and trucks increasing due to a larger population with better fuel economy due to dieselization and improved technology.