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Replacement of chromium containing materials and processes is the focus of extensive research and development activity due to increasingly stringent environmental regulations stemming from hexavalent chromium toxicity concerns. This, in turn, has increased the cost of hardware manufacture. This paper describes the efforts of Boeing Commercial Airplanes in developing a more environmentally suitable alternative process to chromic acid anodizing. Several alternative processes were evaluated prior to selection of a boric-sulfuric acid anodize (BSAA) process. Results of screening tests (including corrosion resistance, paint adhesion, abrasion resistance and fatigue life) and subsequent BSAA process optimization are included.

Gulf Canada's adaptation of the Gulf HydroTreating Process for the manufacture of lubricating oil base stocks is described. The key process operating parameters are discussed, feed stock properties are shown, and the base stocks produced are discussed. Data is then presented on a fully formulated SF/CC quality passenger car engine oil, including results of a 96 000 km (60,000 miles) taxi-cab field trial.

Designing trucks for good ride characteristics is a challenge to the engineer, given the many design constraints imposed by requirements for transport productivity and efficiency. The objective of this lecture is to explain why trucks ride as they do, and the basic mechanisms involved. The response of primary interest is the vibration to which the driver is exposed in the cab. Whole-body vibration tolerance curves give an indication of how those vibrations are perceived at the seat; however, ride studies have shown that visual and hand/foot vibrations are also important to the perception of ride in trucks. The ride environment of the truck driver is the product of the applied excitation and the response properties of the truck. The major excitation sources are road roughness, the rotating tire/wheel assemblies, the driveline, and the engine.

The application of open-circuit, load-sensing hydraulic systems in industrial, marine, and mobile equipment has long provided many advantages to machine designers, manufacturers, distributors, dealers, and end-user customers. Typically, the flow for such systems is provided by variable-displacement piston or vane pumps. However, in some applications, fixed-displacement gear pumps with integral load-sensing valve packages offer a more economical, and (depending on machine duty cycle and other parameters) a more efficient system. This paper will provide an overview of the design and advantages of these units, discuss the essential criteria which must be considered during the “fixed-displacement versus variable-displacement” pump selection process, and describe some typical applications.

When analyzing the time/distance performance of vehicles accelerating from a stopped position, a constant acceleration rate is often assumed. Acceleration profiles as a function of time are examined in this paper in order to identify errors associated with the constant acceleration assumption for a passenger car and a large truck. The paper also includes acceleration data collected from 219 large trucks measured over distances of 50 and 100 feet. For passenger cars, the assumption of constant acceleration is appropriate when evaluating velocity/distance scenarios with displacements of interest greater than 10 ft. For 5 ft or less, variable acceleration is recommended. When time factors are of special interest, attention must be given to the lag times associated with variable acceleration. The lag time does little to affect the velocity/distance relationship; however, it alters time/distance/velocity relationship by as much as 2 seconds.

This study relates the structural stiffness and kinetic energy of impact to the dynamic response of a belted vehicle occupant. Acceleration time histories of impact for structures with different stiffnesses were obtained by performing a finite element analysis using the LS-DYNA3D finite element program and a model representing a structural member made of AISI 4340 steel. For the human body dynamics analysis, the Articulated Total Body (ATB) computer program was used to perform six simulations of a 50 percentile male restrained by a 3-point seatbelt system for a co-linear -Gx impact.

Many side-impact collisions occur at speeds much lower than tests conducted by the National Highway Traffic Safety Administration (NHTSA) and the Insurance Institute for Highway Safety (IIHS). In fact, nearly half of all occupants in side-impact collisions experience a change in velocity (delta-V) below 15 kph (9.3 mph). However, studies of occupant loading in collisions of low- to moderate-severity, representative of many real-world collisions, is limited. While prior research has measured occupant responses using both human volunteers and anthropometric test devices (ATDs), these tests have been conducted at relatively low speeds (<10 kph [<6.2 mph] delta-V). This study evaluated near- and far-side occupant response and loading during two side impacts with delta-V of 6.1 kph and 14.0 kph (3.8 mph and 8.7 mph).

Analyses of driver response time studies and fatal crash statistics were examined to determine: 1. whether all rear-end crash types can be analyzed as one crash type, 2. average braking thresholds for drivers, and 3. the influence cell phone usage has on drivers’ response times when responding to a lead vehicle. The goal of this research is to recommend protocols for investigating LV crashes that is supported by the literature. Two distinct lead vehicle [LV] response time events emerged: LV platoon (two vehicles traveling together in close proximity) and LV looming (a vehicle approaching a stopped or much slower LV). In normal driving, platoon LV events were very common but resulted in very few crashes per exposure. Young drivers were over-represented when they did occur. Onset of the hazardous event was when the LV decelerated, and drivers began braking roughly 3 to 5 seconds before impact.

The qualification requirements of automakers derive from track testing in which road load and moment inputs to a part in x, y and z directions are recorded over a set of driving conditions selected to represent typical operation. Because recorded histories are lengthy, often comprising many millions of time steps, past industry practice has been to specify simplified block cycle schedules for purposes of durability testing or analysis. Simplification, however, depends on imprecise human judgement, and risks fidelity of the inferred life and failure mode relative to actual. Fortunately, virtual methods for fatigue life prediction are available that are capable of processing full, real-time, multiaxial road load histories. Two examples of filled natural rubber ride bushings are considered here to demonstrate. Each bushing is subject to a schedule of 11 distinct recorded track events.

Reducing vehicle CO2 emissions is an important measure to help address global warming. To reduce CO2 emissions on a global basis, Toyota Motor Corporation is taking a multi-pathway approach that involves the introduction of the optimal powertrains according to the circumstances of each region, including hybrid electric (HEVs) and plug-in hybrid electric vehicles (PHEVs), as well as battery electric vehicles (BEVs). This report describes the development of a new PHEV system for the Toyota Prius. This system features a traction battery pack structure, transaxle, and power control unit (PCU) with boost converter, which were newly developed based on the 2.0-liter HEV system. As a result, the battery capacity was increased by 1.5 times compared to the previous model with almost the same battery pack size. Transmission efficiency was also improved, extending the distance that the Prius can be driven as an EV by 70%.

Emissions and fuel economy certification testing for vehicles is carried out on a chassis dynamometer using standard test procedures. The vehicle coastdown method (SAE J2263) used to experimentally measure the road load of a vehicle for certification testing is a time-consuming procedure considering the high number of distinct variants of a vehicle family produced by an automaker today. Moreover, test-to-test repeatability is compromised by environmental conditions: wind, pressure, temperature, track surface condition, etc., while vehicle shape, driveline type, transmission type, etc. are some factors that lead to vehicle-to-vehicle variation. Controlled lab tests are employed to determine individual road load components: tire rolling resistance (SAE J2452), aerodynamic drag (wind tunnels), and driveline parasitic loss (dynamometer in a driveline friction measurement lab). These individual components are added to obtain a road load model to be applied on a chassis dynamometer.

Due to the expense and time commitment associated with extensive product testing, vehicle manufacturers are developing new simulation techniques to verify vehicle component performance with less testing and more confidence in the final product. Battery lifetime is of particular difficulty to predict, since each battery is different and there are many different control scenarios that could be implemented based on the specific requirements of each battery type. In order to solve this problem for a 12V auxiliary lead-acid battery, a battery durability analysis model has been previously adapted from lithium-ion applications, which is capable of verifying the impact of lead-acid battery durability in a short period of time. In this study, calibration tools for this model were developed and are presented here, and durability analysis and verification are performed for the application of new electric vehicles.

An analytic first-order fuel consumption model is developed for FWD 2-motor HEV vehicles which on average achieve 36% EPA Combined efficiency. The premise of this paper is that this is primarily the result of new functionality specific to HEV. Detailed benchmarking data show that in such an HEV the engine not only provides traction power but simultaneously charges the battery. This combined operation of engine and electric powertrain is unique to HEV and is studied using their linear transfer functions. Charging by the engine enables extended electric driving at low traction power, which reduces engine running time and the associated overhead. The analysis predicts an engine duty cycle proportional to the traction power and inversely proportional to the engine output power: the electric driving is limited by the engine’s ability to deliver the required traction work.

Plug-in hybrid electric vehicles (PHEVs) have the capability to drive an appreciable fraction of their miles travelled on electric power from the grid, similar to battery-only electric vehicles (BEVs). However, unlike BEVs which cannot drive unless charged, PHEVs can automatically switch to gasoline power and operate similar to a regular (non-plug-in) hybrid electric vehicle (HEV). Though operating similar to HEV is already beneficial in terms of fuel economy, greenhouse gas (GHG) emissions and criteria pollutants compared to conventional internal combustion engine (ICE) vehicles, much of the attractiveness and allure of PHEVs comes from their capability to drive “almost like a BEV”, but without range anxiety about running out of battery charge.

This paper discusses the dependency between powertrain design and automated driving. The research questions are to what extent automated driving influences the powertrain design and how energy and fuel consumption is affected in comparison to customer driving. For this investigation a concept study is carried out for a D-segment vehicle and multiple powertrain topologies, ranging from non-electrified to plug-in hybrids and battery electric vehicles. In order to answer the research questions, the used development process and the methods for optimizing the drive system are presented accordingly, taking into account all vehicle requirements, the drive system and the components and their interactions with each other. This work focuses on two automated driving functions developed at the Institute of Automotive Engineering of the Technische Universität Braunschweig. The functions are an “automated valet parking” and a “highway pilot”.

Toyota has developed a new 2.4L L4 turbo (2.4L-T) engine with 8AT and 1-motor hybrid electric powertrains for midsize pickup trucks. The aim of these powertrains is to fulfill both strict fuel economy and emission regulations toward “Carbon Neutrality”, while exceeding customer expectations. The new 2.4L L4 turbocharged gasoline engine complies with severe Tier3 Bin30/LEVIII SULEV30 emission regulations for body-on-frame midsize pickup trucks improving both thermal efficiency and maximum torque. This engine is matched with a newly developed 8-speed automatic transmission with wide range and close step gear ratios and extended lock-up range to fulfill three trade-off performances: powerful driving, NVH and fuel economy. In addition, a 1-motor hybrid electric version is developed with a motor generator and disconnect clutch between the engine and transmission.

This work represents an advanced engineering research project partially funded by the U.S. Department of Energy (DOE). Ford Motor Company, FEV North America, and Oak Ridge National Laboratory collaborated to develop a next generation boosted spark ignited engine concept. The project goals, specified by the DOE, were 23% improved fuel economy and 15% reduced weight relative to a 2015 or newer light-duty vehicle. The fuel economy goal was achieved by designing an engine incorporating high geometric compression ratio, high dilution tolerance, low pumping work, and low friction. The increased tendency for knock with high compression ratio was addressed using early intake valve closing (EIVC), cooled exhaust gas recirculation (EGR), an active pre-chamber ignition system, and careful management of the fresh charge temperature.

The current market demand and ever tightening global legislation mandate automotive OEMs to improve vehicle fuel consumption and reduce carbon based emissions. One approach to do so is by downsizing of gasoline engines. The reduced engine displacement causes lesser pumping and frictional losses and lower gas to wall heat transfer making engine more efficient. While downsizing an engine can enhance fuel economy it also brings down the power output. The power lost can be compensated by integrating a turbocharger to the engine to increase the boost pressure however, this again may create an abnormal combustion event known as low-speed pre-ignition (LSPI). The increase of pressure and temperature inside the combustion chamber at high loads also leads to a pre-ignition induced super knock and in severe cases, LSPI leads to broken piston rings, damaged pistons and bent connecting rods.

The kinematic response of vehicle occupants involved in tractor-to-passenger vehicle sideswipes was examined through a series of 13 crash tests. Each test vehicle and its occupants were instrumented with accelerometer arrays to measure and quantify the impact severity at various inter-vehicular angles and impact velocities. The passenger vehicle was occupied by a volunteer test subject in the driver and right-front passenger positions. The impact angle was varied between 3° and 11° to produce a sideswipe collision between the front bumper, steered wheel, and side components of the tractor and the side panels of the struck vehicle. The passenger vehicles were struck at different locations along their longitudinal axis at impact velocities between 3 mph and 11.5 mph. Accelerations were measured at the lumbar, cervicothoracic, and head regions of the driver and right-front passenger of the struck vehicle and the tractor driver.

Modern heavy vehicles may be equipped with an Advanced Driver Assistance System (ADAS) designed to increase highway safety. Depending on the vehicle or manufacturer, these systems may detect objects in a driver’s blind spot, provide an alert when the ADAS determines that the vehicle is leaving its lane of travel without the use of a turn signal, or notify the driver when certain road signs are detected. ADASs also include adaptive cruise control, which adjusts the vehicle’s set cruise speed to maintain a safe following distance when a slower vehicle is detected ahead of the truck. In addition, the ADAS may have a Collision Mitigation System (CMS) component that is designed to help drivers respond to roadway situations and reduce the severity of crashes. CMSs typically use radar or a combination of radar and optical technologies to detect objects such as vehicles or pedestrians in the vehicle’s path.