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The MX-2 neutral buoyancy space suit analogue has been designed and developed at the University of Maryland to facilitate analysis of space suit components and assessment of the benefits of advanced space suit technologies, The MX-2 replicates the salient features of microgravity pressure suits, including the induced joint torques, visual, auditory and thermal environments, and microgravity through the use of neutral buoyancy simulation. In this paper, design upgrades and recent operations of the suit are outlined, including many experiments and tests of advanced space suit technologies, This paper focuses on the work done using the MX-2 to implement and investigate various advanced controls and displays within the suit, to enhance crewmember situational awareness and effectiveness, and enable human-robotic interaction.

The Pride of Maryland is a single seat solar powered trans-continental race car designed and built by engineering students at the University of Maryland. The car competed in G.M. Sunrayce USA, placing third, and has gone on to compete in the World Solar Challenge. This paper outlines the three general areas of design and development for the solar vehicle: aerodynamic, electrical, and mechanical. An exercise in high efficiency, the Pride of Maryland has been extremely successful as both a race car and as an educational tool for training student engineers in “real world” problems.

Smoke detection experiments were conducted in the Microgravity Science Glovebox (MSG) on the International Space Station (ISS) during Expedition 15 in an experiment entitled Smoke Aerosol Measurement Experiment (SAME). The preliminary results from these experiments are presented. In order to simulate detection of a prefire overheated-material event, samples of five different materials were heated to temperatures below the ignition point. The smoke generation conditions were controlled to provide repeatable sample surface temperatures and air flow conditions. The smoke properties were measured using particulate aerosol diagnostics that measure different moments of the size distribution. These statistics were combined to determine the count mean diameter which can be used to describe the overall smoke distribution.

This paper presents results from a smoke detection experiment entitled Smoke Aerosol Measurement Experiment (SAME) which was conducted in the Microgravity Science Glovebox on the International Space Station (ISS) during Expedition 15. Five different materials representative of those found in spacecraft were pyrolyzed at temperatures below the ignition point with conditions controlled to provide repeatable sample surface temperatures and air flow conditions. The sample materials were Teflon®, Kapton®, cellulose, silicone rubber and dibutylphthalate. The transport time from the smoke source to the detector was simulated by holding the smoke in an aging chamber for times ranging from 10 to1800 seconds. Smoke particle samples were collected on Transmission Electron Microscope (TEM) grids for post-flight analysis.

The University of Maryland team converted a model year 2000 Chevrolet Suburban to an ethanol-fueled hybrid-electric vehicle (HEV) and tied for first place overall in the 2000 FutureTruck competition. Competition goals include a two-thirds reduction of greenhouse gas (GHG) emissions, a reduction of exhaust emissions to meet California ultra-low emissions vehicle (ULEV) Tier II standards, and an increase in fuel economy. These goals must be met without compromising the performance, amenities, safety, or ease of manufacture of the stock Suburban. The University of Maryland FutureTruck, Proteus, addresses the competition goals with a powertrain consisting of a General Motors 3.8-L V6 engine, a 75-kW (100 hp) SatCon electric motor, and a 336-V battery pack. Additionally, Proteus incorporates several emissions-reducing and energy-saving modifications; an advanced control strategy that is implemented through use of an on-board computer and an innovative hybrid-electric drive train.

The potential for thermoelectric power generation via waste heat recovery onboard automobiles to displace alternators and/or provide additional charging to a hybrid vehicle battery pack has increased with recent advances in thermoelectric materials processing. A preliminary design/modeling study was performed to optimize waste heat recovery for power generation using a modified radiator incorporating thermoelectric modules. The optimization incorporates not only thermoelectric performance but also critical systems issues such as accessory power consumption, vehicle drag, and added system weight. Results indicate the effectiveness of the thermoelectric module is extremely sensitive to ambient heat rejection and to the operating temperature range of the thermoelectric device.

The University of Maryland FutureTruck Team has redesigned a 2002 Ford Explorer to function as a charge-sustaining parallel hybrid electric vehicle for the 2002-2003 FutureTruck competition. Dubbed the Excite, it is powered by a dedicated E85 3.0L V6 engine coupled to a 21.6 kW peak (10kW continuous), electric motor using a 144V NiMH battery pack. The philosophy behind the UMD plan is to use a smaller, lightweight, dedicated E85 engine in parallel with an electric motor to provide starting and mild assist capabilities. The engine provides similar power to the stock 4.0 L Explorer engine and the electric motor functions as a starter, an alternator, and assists the engine during high power demands. The combination of the two systems provides the Excite with engine-off-at-idle capability, increased efficiency and fuel economy, and decreased emissions while maintaining the utility of a stock SUV.

The control and analysis of magnetic bearings has been primarily based upon classical linear control theory. This approach does not allow for some important system complexities and nonlinearities to be taken into account. The resulting simplifications degrade the overall system performance. This paper investigates the use of a neural network to control a magnetic bearing flywheel energy storage system. A plant simulation is developed as well as a neural network emulator and controller.

AMBER (Active Magnetic Bearing Evaluation Routine) is a computer algorithm developed for the University of Maryland pancake magnetic bearing, which supports and controls a flywheel in a kinetic energy storage system. Because of the gap growth due to centrifugal forces at high speed, the bearing axial load capability degrades and the axial characteristics become critical in the bearing design. AMBER applies magnetic circuit theory, magnetic material saturation curves, coenergy theory, and finite permeance-based elements to solve the air gap flux density and coenergy over a series of incremental axial displacements. Differentiation of the coenergy of the magnetic field yields axial force and stiffness characteristics. An axial test machine is constructed to conduct experiments to verify the flux distribution and axial forces predicted by the model. User interaction with AMBER allows modification of the bearing geometry and composition to optimize future prototypes.

A Capillary Pumped Loop (CPL) is an advanced two-phase heat transport device which utilizes capillary forces developed within porous wicks to move a working fluid. The advantage this system has over conventional thermal management systems is its ability to transfer large heat loads over long distances at a controlled temperature. Extensive ground testing and two flight experiments have been performed over the past decade which have demonstrated the potential of the CPL as a reliable and versatile thermal control system for space applications. While the performance of CPL's as “black boxes” is now well understood, the internal thermo-fluid dynamics in a CPL are poorly known due to the difficulty of taking internal measurements. In order to visualize transient thermohydraulic processes occurring inside an evaporator, a see-through capillary evaporator was built and tested at NASA's Goddard Space Flight Center.

Results from the research projects sponsored by General Motors, Motor Vehicle Fire Research Institute and National Highway Traffic Safety Administration are discussed. In the projects, thermophysical and fire properties of engine compartment fluids and polymer parts of the vehicle were quantified. Burning behaviors of the actual vehicle parts and front and rear crashed vehicle were also examined. Penetration of flames into the passenger compartment was the most critical stage in vehicle crash fire tests. Pain, 2nd and 3rd degree burns, flashover, toxicity, and lethality followed in that order very shortly after the flame penetration. The flame penetration into the passenger compartment from the engine compartment fires in front vehicle crashes was significantly longer (10 to 24 minutes post ignition) than from gasoline pool fires under the vehicle (0.5 to 3.0 minutes post ignition).

In low earth orbit satellite applications, spacecraft power is provided by photovoltaic cells and batteries. Unfortunately, use of batteries present difficulties due to their poor energy density, limited cycle lifetimes, reliability problems, and the difficulty in measuring the state of charge. Flywheel energy storage offers a viable alternative to overcome some of the limitations presented by batteries. FARE, Inc. has built a 50 Wh flywheel energy storage system. This system, called the Open Core Flywheel, is intended to be a prototype energy storage device for low earth orbit satellite applications. To date, the Open Core Flywheel has achieved a rotational speed of 26 krpm under digital control.

A mathematical model of combustion process in a diesel engine has been developed according to the theory of the chain reactions for the higher hydrocarbon compounds. The instantaneous rates of fuel vaporization and combustion are defined by the current values of temperature, pressure, concentration of fuel vapors, overall diffusion rate, fuel injection rate, and mean fuel droplet size in terms of the SMD. Numerical experiments have been carried out for investigating the interdependencies between various combustion-related parameters. Specifically, the effect of fuel droplet size (in terms of SMD) on the subsequent combustion parameters, such as, pressure, temperature, thermodynamic properties of air/gas mixture, heat transfer, fuel vaporization, combustion rate, current A/F ratio, gas mixture composition have been investigating. In addition, the integral indicator parameters of the engine, such as the mean indicated pressure, peak pressure, compression pressure have been analyzed.

This manuscript presents a systematic approach for the design and development of a 403 V, 7 kWh battery pack for a Formula SAE student racing electric car. The pack is made up of 6 individual segments which are connected in series. Each segment has a maximum energy of 1.17 kWh and is made up of 16 arrays connected in series. Each array holds 8 Lithium-ion batteries which are connected in parallel. The overall design of the battery pack is in full compliance with the Formula SAE rules. The manuscript presents the calculation procedure and battery sizing for the power demand of a typical Formula SAE student racing electric car using vehicle dynamics equations. The entire electric traction system is modelled in Matlab/Simulink. The paper also explains the development process of the 7 kWh battery pack and highlights important design considerations, such as busbar sizing.