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An important aspect of an autonomous vehicle system, aside from the crucial features of path following and obstacle detection, is the ability to accurately and effectively recognize visual cues present on the roads, such as traffic lanes, signs and lights. This ability is important because very few vehicles are autonomously driven, and must integrate with conventionally operated vehicles. An enhanced infrastructure has yet to be available solely for autonomous vehicles to more easily navigate lanes and intersections non-visually. Recognizing these cues efficiently can be a complicated task as it not only involves constantly gathering visual information from the vehicle’s surroundings, but also requires accurate real time processing. Ambiguity of traffic control signals challenges even the most advanced computer decision making algorithms. The vehicle then must keep a predetermined position within its travel lane based on its interpretation of its surroundings.

This study investigates combustion and emissions of Jet-A in an indirect injection (IDI) compression ignition engine and a direct injection (DI) compression ignition engine at 4.5 bar IMEP and 2000 RPM. The Jet-A was blended with ULSD that resulted in 75%Jet-A and 25% ULSD#2 by mass. Both engines were instrumented with Kistler pressure sensors in the main chamber and the IDI engine had a second pressure sensor in the pre-chamber. Combustion properties and emissions from both engines using the 75% jet-A blend (75Jet-A) were compared to a baseline test of Ultra Low Sulfur Diesel #2 (ULSD). The ignition delay was shorter when running on 75Jet-A compared to ULSD in the DI engine. For ULSD, the ignition delay was 1.8 ms and it reduced to 1.7 ms when operating on 75Jet-A (difference of 6%). In the IDI engine the ignition delay for both fuels was 2.3 ms based off the gross heat release in the Pre-Chamber.

In this study, Premixed Charge Compression Ignition (PCCI) was investigated with alternative fuels, S8 and n-butanol. The S8 fuel is a Fischer Tropsch (FT) synthetic paraffinic kerosene (SPK) produced from natural gas. PCCI was achieved with a dual-fuel combustion incorporating 65% (by mass) port fuel injection (PFI) of n-butanol and 35% (by mass) direct injection (DI) of S8 with 35% exhaust gas recirculation. The experiments were conducted at 1500 rpm and varied loads of 1-5 bar brake mean effective pressure (BMEP). The PCCI tests were compared to an ultra-low sulfur diesel no. 2 (ULSD#2) baseline in order to determine how the alternative fuels effects combustion, emissions, and efficiencies. At 3 and 5 bar BMEP, the heat release in the PCCI mode exhibited two regions of high temperature heat release, one occurring near top dead center (TDC) and corresponds to the ignition of S8 (CN 62), and a second stage occurring ATDC from n-butanol combustion (CN 28).