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The first concept and early experiments of a mechanical counter pressure (MCP) spacesuit were published by Webb in the late 1960's. MCP provides an alternative approach to the conventional full pressure suit that bears some significant advantages, such as increased mobility, dexterity, and tactility. The presented ongoing research provides a thorough investigation of the physiological effect of mechanical counter pressure applied onto the human skin. In this study, we investigated local microcirculatory effects produced with negative and positive ambient pressure on the lower body as a preliminary study for a lower body garment. The data indicates that the positive pressure was less tolerable than negative pressure. Lower body negative and positive pressure cause various responses in skin blood flow due to not only blood shifts but also direct exposure to pressure differentials.

The first concept and early experiments of a Mechanical Counter Pressure (MCP) spacesuit were published by Webb in the late 1960's. MCP provides an alternative approach to the conventional full pressure suit that bears some significant advantages, such as increased mobility, dexterity, and tactility. The presented ongoing research provides a thorough investigation of the physiological effect of mechanical counter pressure applied onto the human skin. In this study, we investigated local microcirculatory effects produced with negative and positive ambient pressure on a bare arm, and with a MCP glove and sleeve. The data indicates that the MCP glove and sleeve effectively counteracted the adverse effects of negative environmental pressure.

The first concept and early experiments of a Mechanical Counter Pressure (MCP) spacesuit were published by Webb in the late 1960’s. MCP provides an alternative approach to the conventional full pressure suit that bears some potential advantages, such as increased mobility, dexterity, and tactility. The presented ongoing research provides a thorough investigation of the physiological effect of mechanical counter pressure applied onto the human skin. Preliminary results are presented from glovebox testing with an existing MCP glove. The data indicates that properly applied mechanical counter pressure greatly reduces the effect of low-pressure exposure, which makes MCP a viable technology for spacesuit gloves.

This paper introduces a novel method for an electric power generation system (EPGS) employing a lead-unity-lag (LUL) permanent-magnet (PM) generator operation for a direct current (DC) power distribution bus. In addition, background information of the prior art for a leading power factor EPGS is discussed. The concept of the new approach is defined and a comparative analysis between the new and old state-of-the-art solutions are documented. The performance features and technical details of the system parameters with respect to power generation system requirements are presented and discussed. Analysis and testing results are included. Finally, the advantages of this system, a conclusion, and recommendations for future work are provided. Test results from a system having elements of this novel approach are included. With this method for an LUL EPGS, the capability of the high-performance electric power generation systems is improved substantially.

Many electronic parts have life cycles that are shorter than the life cycle of the product they are in. Life cycle mismatches caused by the obsolescence of electronic parts can result in significantly sustainment costs for long life systems. In particular, avionics often encounters part obsolescence problems before being fielded and nearly always experience part obsolescence problems during their field life. This paper presents a methodology for determining the optimum design refresh (redesign) schedule for long field life electronic systems based on forecasted electronic part obsolescence and a mix of obsolescence mitigation approaches ranging from lifetime buys to part substitution.

This paper presents a novel method and system for an electric power alternating-current (AC)-to-direct-current (DC) converter employing composite technology. The term composite entails utilization of more than one type of conversion operating in parallel. In addition, background information for the prior art, based on conventional autotransformer rectifier units (ATRUs), and active converters are discussed. The major requirements of AC-to-DC converters from both functional and protection perspectives are provided. The concept of the new approach is defined. Comparative analysis between the new and old methods is documented. The performance features and technical details of the system parameters with respect to AC-to-DC converter system requirements are presented and discussed. Analysis, simulation results, and test data are included. Finally, the advantages of this technology, which nearly doubles power density compared to the state-of-the-art, are summarized and a conclusion included.

Water recovery from wastewater is essential for the success of long-term missions to the Moon and Mars and human crew operations during explorations of these planets. Honeywell International and the team consisting of Thermodistillation Co. ( Kyiv, Ukraine) and NASA JSC Crew and Thermal Systems Division are developing an efficient wastewater processing subsystem that is based on centrifugal vacuum distillation. This subsystem will be tested at the NASA JSC Advanced Water Recovery Systems Development Facility. The Wastewater Processing Cascade Distillation Subsystem (CDS) utilizes an innovative and proven multi-stage thermodynamic process to produce purified water efficiently, and its rotary centrifugal design provides gas/liquid phase separation and liquid transport (pumping) under microgravity conditions.