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The Lunar Electric Rover (LER), which was formerly called the Small Pressurized Rover (SPR), is currently being carried as an integral part of the lunar surface architectures that are under consideration in the Constellation Program. One element of the LER is the suit port, which is the means by which crew members perform Extravehicular Activities (EVAs). Two suit port deliverables were produced in fiscal year 2008: a 1-g suit port concept evaluator for functional integrated testing with the LER 1-g concept vehicle and a functional and pressurizable Engineering Unit (EU). This paper focuses on the 1-g suit port concept evaluator test results from the Desert Research and Technology Studies (D-RATS) October 2008 testing at Black Point Lava Flow (BPLF), Arizona. The 1-g suit port concept evaluator was integrated with the 1-g LER cabin and chassis concepts.

A 10 KWe dual-mode space power system concept has been identified which is based on INEL's Small Externally-fueled Heat Pipe Thermionic Reactor (SEHPTR) concept. This power system will enhance user capabilities by providing reliable electric power and by providing two propulsion systems; electric power for an arc-jet electric propulsion system and direct thrust by heating hydrogen propellant inside the reactor. The low thrust electric thrusters allow efficient station keeping and long-term maneuvering. The direct thrust capability can provide tens of pounds of thrust at a specific impulse of around 730 seconds for maneuvers that must be performed more rapidly. The direct thrust allows the nuclear power system to move a payload from Low Earth Orbit (LEO) to Geosynchronous Earth Orbit (GEO) in less than one month using approximately half the propellant of a cryogenic chemical stage.

System requirements and Interface Control Drawings (ICDs) make a variety of demands for MIL-STD-1553 remote terminals (RTs). Among these requirements are the need to ensure data integrity and sample data consistency, the need to perform bulk (multi-message) data transfers, and the need to offload the operation of the host CPU to the greatest degree possible. This latter requirement is reflected in such specifications as CPU spare bandwidth. The latest 1553 terminals provide a variety of choices for performing the different types of transfers. This paper provides a discussion of the hardware and software techniques for achieving these objectives. Three different schemes for RT subaddress memory management are presented: single message, circular buffer, and double buffered. For receive and transmit messages, these include fully synchronous single message transfers, asynchronous single message transfers, and multi-message transfers.

BlueStar Advanced Technology Corporation (BATC) as part of its participation in the USAF/NASA Li Ion Battery Development Consortium has developed a candidate 25-Ah cell for the Mars 2001 Lander. Although the capacity and cycle life requirements for this application are relatively modest, the low temperature performance (−20°C) and pulse discharge requirements (60A) are somewhat more challenging. Geometric requirements within the spacecraft also constrain the cell design leading to a cell with an aspect ratio quite different from those 25-Ah Li ion cells previously developed by BATC. The design of this cell and its compliance with the performance requirements of the mission will be discussed.

Sundstrand is investigating 270-Vdc/hybrid 115-Vac electrical power generating and distribution systems technology so as to be well prepared to offer such systems for future aircraft applications. The approach taken has been to design, build, and test a representative system that meets or exceeds the tightest of the performance standards as defined by miliary standards. This paper describes a single-channel, 120-kW hybrid system and presents some typical performance data. The dc bus supplies a 30-kVA, 400-Hz, 115-Vac inverter; constant power load banks of up to 150 kW; and a resistive load bank of up to 90 kW. System simulation studies indicated the potential for unstable operation due to the negative impedance of the constant power load in conjunction with the source ripple filter and the load EMI filters. Unstable voltage and current were observed in system testing when the magnitude of the source impedance was not sufficiently below that of the load impedance.

Sundstrand has been investigating 270-Vdc/hybrid 115-Vac electrical power generating systems (EPGS) technology in preparation for meeting the electrical power generating system (EPGS) requirements for future aircraft (1). Systems such as the one being investigated are likely to be suitable for the More-Electric Aircraft (MEA) concepts presently under industry and military study. The present Sundstrand single-channel testbed is being further expanded to better understand the electrical system performance characteristics and power quality requirements of an MEA in which traditional mechanical subsystems are replaced by those of a “more-electric” nature. This paper presents the most recent Sundstrand 270-Vdc system transient performance data, and describes the modifications being made to the 270-Vdc/hybrid 115-Vac testbed.

Innovative Power Solutions (IPS), LLC has developed a 300A and a 500A 28 VDC Brushless Wound Rotor Starter/Generator (S/G) system. These systems are capable of replacing brush type S/G or Air Turbine Starters by presenting an adequate Torque vs. Speed performance. The S/G system developed by IPS consists of the Starter/Generator (Motor/Generator) and S/G Control Unit (SGCU).

Ultrasound is attractive for medical imaging in space because scanners can be small, lightweight, low power, and have minimal electromagnetic emissions. In addition, unlike conventional 2-D ultrasound. 3-D ultrasound allows an operator with no diagnostic skills to collect high-quality scans that can be interpreted by a remote expert. This allows 3-D ultrasound to be used effectively in remote locations. These capabilities are illustrated by the MUSTPAC-1, a portable 3-D ultrasound telemedicine system recently developed for the U.S. military. Design, implementation, and field experiences with the MUSTPAC-1 are discussed, and extensions for use in space are proposed.

A lightning mapping system has been developed that locates the sources of VHF radiation from lightning discharges in three spatial dimensions and time. The system consists of several VHF receivers distributed over an area of about 100 km diameter. The system locates VHF radiation sources over the array with an accuracy of about 100 m. The system locates sources out to 250 km from the center of the array with reduced accuracy. The observations are found to reflect the basic charge structure of electrified storms.

A very high power source solution was developed for the Non Line of Sight Launch System Container Launch Unit (NLOS-LS CLU). The power source solution has been shown to be capable of providing the required 72 continuous hours of operation and high power (3560 watts) to sustain launch capability. The power source consists of 18 BB-2590/U batteries connected in parallel in three layers. Several CLU battery systems have been delivered to the PEO and have been well accepted. The Army is using standard rechargeable batteries, is currently being upgraded with SMBus capability and higher capacity lithium-ion cells. For this reason, the CLU power source has been manufactured with SMBus capability. This paper will discuss the performance of one layer of the CLU power source to simulate the whole power load.

The need to improve quality while reducing cost in aerospace manufacturing is requiring new manufacturing methods and processes. Advanced technologies, such as 3D Image Metrology, offer great potential to lean manufacturing, if properly integrated into the production process. Over the last years 3D Image Metrology has developed a level of performance, which make it ideally suited for this purpose. These capabilities include the automatic in-process inspection of tools and parts before machining, machine control for highly accurate positioning during the machining operation, and in-process inspection during machining. This offers jig-less assembly, lower inventory, faster part throughput, and many more advantages.

In CFD (Computational Fluid Dynamics) verification of vehicle aerodynamics, detailed velocity measurements are required. The conventional 2D-PIV (Two Dimensional Particle Image Velocimetry) needs at least twice the number of operations to measure the three components of velocity ( u,v,w ), thus it is difficult to set up precise measurement positions. Furthermore, there are some areas where measurements are rendered impossible due to the relative position of the object and the optical system. That is why the acquisition of detailed velocity data around a vehicle has not yet been attained. In this study, a detailed velocity measurement was conducted using a 3D-PIV measurement system. The measurement target was a quarter scale SAE standard vehicle model. The wind tunnel system which was also designed for a quarter scale car model was utilized. It consisted of a moving belt and a boundary suction system.

The objective of this project was to replace electromechanical power line contactors with a Static Transfer Switch (STS) to improve the transfer of electrical power between aircraft generators and decrease required maintenance. The switch requirements include high reliability, lightweight, and high speed (less than 15mS) power transfer. An STS can shorten the bus transfer time to less than the “ride-through” of aircraft electronic loads and therefore have the ability to control and transfer electrical power while maintaining critical mission requirements. The content of this paper and presentation will discuss the initial problem, the research and development approach, design, and initial testing of the STS.

Vertical-Junction-Field-Effect-Transistors (VJFETs) are currently the most mature SiC devices for high power/temperature switching. High-voltage VJFETs are typically designed normally-on to ensure voltage control operation at high current-gain. However, to exploit the high voltage/temperature capabilities of VJFETs in a normally-off high-current voltage-controlled switch, high-voltage normally-on and low-voltage normally-off VJFETs were connected in the cascode configuration. In this paper, we review the high temperature DC characteristics of VJFETs and 1200 V normally-off cascode switches. The measured parameter shifts in the 25°C to 300°C temperature range are in excellent agreement with theory, confirming fabrication of robust SiC VJFETs and cascode switches.

The transition towards More Electric Aircraft (MEA) architectures has challenges relating to integration of power electronics with the starter generator system for on-engine application. To efficiently operate the power electronics in the hostile engine environment at high switching frequency and for better thermal management, use of silicon carbide (SiC) power devices for a bi-directional power converter is examined. In this paper, development of a 50 kVA bi-directional converter operating at an ambient temperature of about 2000C is presented. The design and operation of the converter with details of control algorithm implementation and cooling chamber design are also discussed.

Unguided sounding rockets, also known as sub-orbital rockets, are vehicles that carry scientific experiments and/or sensors to collect data during their trajectory. These rockets lack active control but are capable of traversing the Earth’s atmosphere. It is crucial to thoroughly analyze the flight parameters during the preliminary design phase. The Open Rocket flight simulation software, developed by Sampo Niskanen, is a widely used open-source project. However, it has some simplifications in comparison to its documentation. It does not specify the calculations of critical parameters required for the rocket’s stability during its flight. Additionally, it does not calculate data related to dynamic stability, which encompasses the system’s ability to make disturbances corrections during the rocket’s trajectory. Consequently, this study presents a flight simulation of a rocket with 6 degrees of freedom using Matlab/Simulink.

Enemy threats during Operation Desert Storm drove many Allied ground attack aircraft to medium altitude to deliver their weapons. Although many Precision Guided Munitions (PGMs) proved to be highly accurate at increased heights, the majority of bombs dropped from medium altitude were low-drag general purpose bombs (LDGP). The aircraft carrying the LDGPs traded accuracy for altitude in order to reduce the risk to aircraft and crews. This event helped highlight the need to drop LDGP weapons more accurately. Additionally, there are environments where even many current PGMs are ineffective. During the Gulf War, for example, smoke from the Kuwaiti oil fires obscured the skies, prohibiting the use of laser guided bombs. Currently there is a program in testing that is designed to fill these operational gaps. The Joint Direct Attack Munition (JDAM) is being developed to convert our inventory of LDGPs into PGMs and modeling/simulation is playing a vital role in its design.

This paper describes ongoing research into Metrology-integrated robot control. The research is a part of an ongoing EU funded aircraft industry project – ADFAST*. The ADFAST project tries to implement the use of industrial robots in low-volume production, high-demand-on-accuracy operations and for dynamic force compensation. To detect and compensate deflection in industrial robots during a process, the robot uses a metrology system. The metrology system supervises the tool center point of the robot as it executes its processes. Leica has recently released a new metrology system; the LTD800, which measures distances with laser interferometry and can simultaneously measure orientation of targets, through photogrammetry, using an additional camera on top of the measuring unit. This paper will describe theory and results from tests performed on integrating the LTD800 with the robot.

The 757/767 Flight Management System provides the initial operational implementation of an integrated guidance, control and display equipments based upon digital technology for commercial transport airplanes. The applied equipments are based upon the new ARINC 700 series characteristics developed by the Industry over the past five years. These characteristics were developed on the basis of limited operational experience with selected elements of the system and upon R&D efforts within the Industry. The System features automatic/manual flight profiles for optimum economics, all weather landing including rollout guidance, electronic primary flight instruments based on color (shadow mask) CRTs, inertial attitude/velocity reference based upon laser gyros, improved caution/warning and other improved performance/functional features. The system also provides significant improvements in line and shop maintenance features.