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The goal of this interview analysis was to explore and document the perceptions of two unique lane centering systems (S90’s Pilot Assist and CT6’s Super Cruise). Both systems offer a similar type of functionality (adaptive cruise control and lane centering), but have significantly different design philosophies and HMI (Human-Machine Interface) implementations. Twenty-four drivers drove one of the two vehicle models for a month as part of a field operational test (FOT) study. Upon vehicle return, drivers took part in a 60-minute semi-structured interview covering their perceptions of the vehicle’s various advanced driver-assistance systems (ADAS). Transcripts of the interviews were coded by two researchers, who tagged each statement with relevant system and perception code labels. For analysis, the perception codes were grouped into larger thematic bins of safety, comfort, driver attention, and system performance.

Biofuel can enable a sustainable transport solution and lower greenhouse gas emissions compared to standard fuels. This study focuses on biodiesel, implemented in the easiest way as drop in fuel. When mixing biodiesel into diesel one can run into problems with solubility causing contaminants precipitating out as insolubilities. These insolubilities, also called soft particles, can cause problems such as internal injector deposits and nozzle fouling. One way to overcome the problem of soft particles is by filtration. It is thus of great interest to be able to quantify fuel filters’ ability to intercept soft particles. The aim of this study is to test different fuel filters for heavy-duty engines and their ability to filter out synthetic soft particles. A custom-built fuel filter rig is presented, together with some of its general design requirements. For evaluation of the efficiency of the filters, fuel samples were taken before and after the filters.

In today's highly competitive automotive markets manufacturers must provide high quality products to survive. Manufacturers can achieve higher levels of quality by changing or improving their manufacturing process and/or by product inspection where many strategies with different cost implications are often available. Cost of Quality (CoQ) reconciles the competing objectives of quality maximization and cost minimization and serves as a useful framework for comparing available manufacturing process and inspection alternatives. In this paper, an analytic CoQ framework is discussed and some key findings are demonstrated using a set of basic inspection strategy scenarios. A case of a welded automotive assembly is chosen to explore the CoQ tradeoffs in inspection strategy selection and the value of welding process improvement. In the assembly process, many individual components are welded in series and each weld is inspected for quality.

Current CJ-4 lubricant specifications place chemical limits on diesel engine oil formulations to minimize the accumulation of lubricant-derived ash in diesel particulate filters (DPF). While lubricant additive chemistry plays a strong role in determining the amount and type of ash accumulated in the DPF, a number of additional factors play important roles as well. Relative to soot particles, whose residence time in the DPF is short-lived, ash particles remain in the filter for a significant fraction of the filter's useful life. While it is well-known that the properties (packing density, porosity, permeability) of soot deposits are primarily controlled by the local exhaust conditions at the time of particle deposition in the DPF, the cumulative operating history of the filter plays a much stronger role in controlling the properties and distribution of the accumulated ash.

On-engine surge detection could help in reducing the safety margin towards surge, thus allowing higher boost pressures and ultimately low-end torque. In this paper, experimental data from a truck turbocharger compressor mounted on the engine is investigated. A short period of compressor surge is provoked through a sudden, large drop in engine load. The compressor housing is equipped with knock accelerometers. Different signal treatments are evaluated for their suitability with respect to on-engine surge detection: the signal root mean square, the power spectral density in the surge frequency band, the recently proposed Hurst exponent, and a closely related concept optimized to detect changes in the underlying scaling behavior of the signal. For validation purposes, a judgement by the test cell operator by visual observation of the air filter vibrations and audible noises, as well as inlet temperature increase, are also used to diagnose surge.

The effect of blockage due to the presence of the wind tunnel walls has been known since the early days of wind tunnel testing. Today there are several blockage correction methods available for correcting the measured aerodynamic drag. Due to the shape of the test object, test conditions and wind tunnel dimensions the effect on the flow may be different for two cab variants. This will result in a difference in the drag delta between so-called open-road conditions and the wind tunnel. This makes it more difficult to evaluate the performance of two different test objects when they are both tested in a wind tunnel and simulated in CFD. A numerical study where two different cab shapes were compared in both open road condition, and in a digital wind tunnel environment was performed.

In order to increase the internal combustion engine efficiency turbocharging is today widely used. The trend, in modern engine technology, is towards higher boost pressures while keeping the combustion pressure raise relatively small. The turbocharger surge occurs if the pressure at the outlet of the compressor is greater than it can maintain, i.e., a reverse flow will be induced. In presence of such flow conditions instabilities will occur which can couple to incident acoustic (pressure) waves and amplify them. The main objective of the present work is to propose a novel method for investigation of turbocharger flow instabilities or surge precursors. The method is based on the determination of the acoustic two-port data. The active part of this data describes the sound generation and the passive part the scattering of sound. The scattering data will contain information about flow-acoustic interaction and amplification of sound that could occur close to surge.

Advances in avionics and display technology are significantly changing the cockpit environment in current transport aircraft. The MIT Aeronautical Systems Lab (ASL) has developed a part-task flight simulator specifically to study the effects of these new technologies on flight crew situational awareness and performance. The simulator is based on a commercially-available graphics workstation, and can be rapidly reconfigured to meet the varying demands of experimental studies. The simulator has been successfully used to evaluate graphical microburst alerting displays, electronic instrument approach plates, terrain awareness and alerting displays, and ATC routing amendment delivery through digital datalinks.

EQUIPMENT for measuring vibration in airplane structures and powerplants during actual flight is described in this paper. This development is the result of a cooperative research program carried out by the Bureau of Aeronautics of the U. S. Navy and the Massachusetts Institute of Technology with contributions of improvements in design and new features by the Sperry Gyroscope Co., Inc. In its essentials, the M.I.T.-Sperry Apparatus consists of a number of electrical pickup units which operate a central amplifying and recording unit. The recorder is a double-element photographic oscillograph. Each pickup is adapted especially to the type of vibration that it is intended to measure and is made so small that it does not appreciably affect the vibration characteristics of the member to which it is attached rigidly. By using a number of systematically placed pickups, all the necessary vibration information on an airplane can be recorded during a few short flights.

This paper describes a three component strain gage balance designed to measure aerodynamic forces exerted on small automobile models when subjected to turbulence in an experimental wind tunnel. The instrument is described and the details of obtaining values with it are fully explained. Although tests were conducted on these models at quarter-scale Reynolds number, results agree closely with similar tests on larger models. The balance makes practical some unusual preliminary investigations before developing full-scale prototypes.

Thermal Barrier Coatings (TBCs) may be used on the inner surfaces of exhaust manifolds in heavy-duty diesel engines to improve the fuel efficiency and prolong the life of the component. The coatings need to have a long thermal cyclic life and also be able to reduce the temperature in the substrate material. A lower temperature of the substrate material reduces the oxidation rate and has a positive influence on the thermo-mechanical fatigue life. A test rig for evaluating these properties for several different coatings simultaneously in the correct environment was developed and tested for two different TBCs and one oxidation-resistant coating. Exhausts were redirected from a diesel engine and led through a series of coated pipes. These pipes were thermally cycled by alternating the temperature of the exhausts. Initial damage in the form of cracks within the top coats of the TBCs was found after cycling 150 times between 50°C and 530°C.

The increased rates of research on complex fuel blends in engine applications poses a need for more efficient and accurate fuel blending processes in engine laboratories. Making the fuel blending process automatic, effective, accurate and flexible saves time, storage space and cost without compromising the tests of future fuel alternatives. To meet these requirements, an automatic fuel blending system, following a sequential batch process, was designed and tested for engine laboratory application. The fuel blending system was evaluated in terms of functionality, safety, accuracy and repeatability. The functionality and safety was evaluated through a risk analysis. Whereas, the accuracy and repeatability of the system was investigated through blend preparation tests. The results show that the minimum fuel mass limitation of the system is 0.5 kg. This allows for blends with fuel ratios as low as 7 vol-% to be prepared by the system.

The formation of deposits in the fuel systems of heavy-duty engines, using drop-in fuels, has been reported in recent years. Drop-in fuels are of interest because they allow higher levels of alternative fuels to be blended with conventional fuels that are compatible with today’s engines. The precipitation of insolubles in the drop-in fuel can lead to clogging of fuel filters and internal injector deposits, resulting in increased fuel consumption and engine drivability problems. The possible mechanisms for the formation of the deposits in the fuel system are not yet fully understood. Several explanations such as operating conditions, fuel quality and contamination have been reported. To investigate injector deposit formation, several screening laboratory test methods have been developed to avoid the use of more costly and complex engine testing.

Reducing the carbon emissions associated with ICE- containing vehicles is a complimentary step towards carbon neutrality alongside the introduction of vehicles using newer energy vectors. In this study, the authors investigated emissions and efficiency impact of fully renewable E10-grade gasoline fuels blended with sustainable components at both 90 RON and 96 RON in comparison with reference regular E0 and premium certification gasolines across a range of ICE vehicle applications. Both renewable fuels were blended to the Japan JIS K2022 2012 E10 specification. The study shows very low carbon gasolines are technically feasible and potentially have an important role to play in decarbonizing both new advanced technology ICE vehicles and, critically, the existing ICE vehicle parc in the transition towards a zero emissions future.