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This study presents the utilization of the hardware-in-the-loop (HIL) approach for regenerative braking (regen) control enhancement efforts for the power split hybrid vehicle architecture. The HIL stand used in this study includes a production brake control module along with the hydraulic brake system, constituted of an accelerator/brake pedal assembly, electric vacuum booster and pump, brake hydraulic circuit and four brake calipers. This work presents the validation of this HIL simulator with real vehicle data, during mild and heavy braking. Then by using the HIL approach, regen control is enhanced, specifically for two cases. The first case is the jerk in deceleration caused by the brake booster delay, during transitions from regen to friction braking. As an example, the case where the regen is ramped out at a low speed threshold, and the hydraulic braking ramped in, can be considered.

Plugin Hybrid Electric Vehicles (PHEV) have a large battery which can be used for electric only powertrain operation. The control system in a PHEV must decide how to spend the energy stored in the battery. In this paper, we will present a prototype implementation of a PHEV control system which saves energy for electric operation in pre-defined geographic areas, so called Green Zones. The approach determines where the driver will be going and then compares the route to a database of predefined Green Zones. The control system then reserves enough energy to be able to drive the Green Zone sections in electric only mode. Finally, the powertrain operation is modified once the vehicle enters the Green Zone to ensure engine operation is limited. Data will be presented from a prototype implementation in a Ford Escape PHEV

Plug in hybrid electric vehicles (PHEVs) have gained interest over last decade due to their increased fuel economy and ability to displace some petroleum fuel with electricity from power grid. Given the complexity of this vehicle powertrain, the energy management plays a key role in providing higher fuel economy. The energy management algorithm on PHEVs performs the same task as a hybrid vehicle energy management but it has more freedom in utilizing the battery energy due to the larger battery capacity and ability to be recharged from the power grid. The state of charge (SOC) profile of the battery during the entire driving trip determines the electric energy usage, thus determining overall fuel consumption.

The production of essential commodities (O2, H2 O, and edible biomass) and removal of CO2 by higher plants in bioregenerative life support systems would be seriously limited by the occurrence of disease epidemics. Among several treatment possibilities is ultraviolet (UV) radiation, which is one of the preferred sterilization techniques due to cost considerations and observed effectiveness against pathogens in hydroponic systems. Doses of 20 to 40 mW.s/cm2 as estimated in a laboratory flowthrough apparatus inactivated 99.99% of Pythium aphanidermatum, a common pathogen of hydroponic crops. Inactivation increased logarithmically with UV radiation dose. NCER (Net Carbon Exchange Rate) provides an indirect method to determine the effectiveness of UV in reducing Pythium infection, by measuring any changes in primary plant productivity.

The occurrence of disease epidemics in bioregenerative life support systems would seriously limit the production of essential life support requirements. The capacity of diseased plants in closed environment chambers to scrub CO2 was studied with lettuce plants infected with a common greenhouse pathogen, Pythium.At harvest, infected lettuce showed less edible biomass, decreased leaf area, and reduced photosynthesis averaging 50% on a per chamber basis. These results and others are discussed to show the potential of using existing instrumentation in life support systems to monitor the health of the plant canopy, predicting early onset of disease and refining remediation strategies.