Advances in Experimental Medicine and Biology, 1988
Our new method is comparable to the standard, "open-end" tonometer system and incorpora... more Our new method is comparable to the standard, "open-end" tonometer system and incorporates all its abilities to monitor oxygen tension and perfusion. The new device has the advantage of being completely sealed, providing a true, continuous direct measurement over several days, with freedom of movement for the patient without operator attention and with improved stability of the electrode, which minimizes the drift artifacts previously encountered. These improvements will facilitate routine clinical monitoring of tissue oxygen tension.
Wireless communications has more to offer for spacecraft avionics than just reduced mass and spac... more Wireless communications has more to offer for spacecraft avionics than just reduced mass and space. A team at NASA Ames Research Center (ARC) is actively involved in designing and implementing wireless systems, and is part of a multi-center NASA effort to investigate wireless sensor networks (WSN) for spacecraft sponsored by the NASA Engineering and Safety Center. In this paper, we
Advances in experimental medicine and biology, 1988
Our new method is comparable to the standard, "open-end" tonometer system and incorpora... more Our new method is comparable to the standard, "open-end" tonometer system and incorporates all its abilities to monitor oxygen tension and perfusion. The new device has the advantage of being completely sealed, providing a true, continuous direct measurement over several days, with freedom of movement for the patient without operator attention and with improved stability of the electrode, which minimizes the drift artifacts previously encountered. These improvements will facilitate routine clinical monitoring of tissue oxygen tension.
Revolutionary capabilities for robust control of inflatable Lunar and Martian transit vehicles an... more Revolutionary capabilities for robust control of inflatable Lunar and Martian transit vehicles and planetary habitats can be developed using advanced wireless network technology and modular avionics coupled with facile human to system interfaces. Fully wireless modular avionics would eliminate any cabling associated with power and data transmission, allowing easy deployment of flexible control systems and human interfaces. Furthermore, wearable human interface systems hosting virtual reality interaction methods can provide significant improvement in human situational awareness and control of dynamic space systems. The crew can interact with intelligent software agents providing human-like interaction using speech. These advanced information management systems would incorporate intelligent software agents to assist the crew in performing vehicle and mission operations. Advances in robust wireless data communications and wireless power transmission are the key technologies that enable...
The Intelligent Mobile Technologies (IMT) group at NASA Ames Research Center is developing new te... more The Intelligent Mobile Technologies (IMT) group at NASA Ames Research Center is developing new technologies that may be useful in supplementing the International Space Station (ISS) data system. The crewmembers would like to have a capability for easily displaying ...
As the technology matures, wireless networks are being used in more applications providing signif... more As the technology matures, wireless networks are being used in more applications providing significant benefits to mobile users. There are now many products, complying with wireless network standards 802.11 and 802.11b, for linking mobile computing elements together and into the Internet using radio signals. Wireless networks provide mobility, but offer lower reliability and performance compared to wired networks. Standard methods
Canada contains a unique site for possible analogue studies of Mars, from Mars-related science to... more Canada contains a unique site for possible analogue studies of Mars, from Mars-related science to studies of technologies that may be used for robotic and human exploration of other planets. This is the Haughton Crater, on Devon Island, Nunavut, in the ...
Mobile Agents (MA) is an advanced Extra-Vehicular Activity (EVA) communications and computing sys... more Mobile Agents (MA) is an advanced Extra-Vehicular Activity (EVA) communications and computing system to increase astronaut self-reliance and safety, reducing dependence on continuous monitoring and advising from mission control on Earth. MA is voice controlled and provides information verbally to the astronauts through programs called “personal agents.” The system partly automates the role of CapCom in Apollo-including monitoring and managing navigation, scheduling, equipment deployment, telemetry, health tracking, ...
ABSTRACT Heterogeneous Spacecraft Networks (HSNs) are network environments in which spacecraft fr... more ABSTRACT Heterogeneous Spacecraft Networks (HSNs) are network environments in which spacecraft from different missions and institutions can communicate with each other at low cost and with low impact on overall system resources. The Mission Design Center (MDC) at NASA Ames Research Center has been studying solutions for low cost multi-spacecraft systems for a number of years. One may now build on the idea to interconnect clusters of spacecraft with each other to have them act as mobile nodes belonging to the same collaborative mission. Recent progress in small satellite technology is significant, and one of the advantages of small satellites lies precisely in the large quantity of spacecraft that can be produced at accessible costs. It follows naturally that small satellites are an interesting candidate platform for development and demonstration of the HSN concept. This paper is the second in a series of three companion papers. The general concept of operations for HSNs in LEO and a number of future applications are proposed in the first paper [6], while enabling technology such as devices and lower layer protocols are discussed in paper three [7]. In this paper, we pick up the scenario of a low-cost and multi-institutional network of Earth Observation (EO) missions in LEO and conduct network performance analysis using the AGI System Tool Kit (STK) and the open-source Network Simulator (NS-3). A multi-spacecraft network consolidates the individual capabilities of each spacecraft from different institutions by combining benefits of both frequent revisit and concentrated observation. Complementary and correlated data could be collected simultaneously from a large set of distributed spacecraft utilizing HSN capability. In this specific configuration, communication distance between spacecraft, related delays and error rate are the major factors in network performance. Also, average duration of communication opportunities between spacecraft is usually very limited. Thus, it is i- portant to simulate orbital dynamics, link margins, and protocols simultaneously to analyze network performances. In this paper, we compare some existing protocols to obtain a measure for the practical performance of the candidate network. We focus on best-effort data delivery, an approach necessitated by the severe constraints on communications resulting from low-cost and low system resource small spacecraft. In the application layer, we show that packet size and data rate of a source node also affect overall performance of the network. We present the resulting figures of merit from our simulations. The paper concludes with a summary of the simulation results.
Abstract-Future human planetary exploration field teams will need daily communications with their... more Abstract-Future human planetary exploration field teams will need daily communications with their base and with mission control. A remote field wireless digital network will be a requirement for safe and productive human exploration. Proper selection of radio-frequency hardware ...
Advances in Experimental Medicine and Biology, 1988
Our new method is comparable to the standard, "open-end" tonometer system and incorpora... more Our new method is comparable to the standard, "open-end" tonometer system and incorporates all its abilities to monitor oxygen tension and perfusion. The new device has the advantage of being completely sealed, providing a true, continuous direct measurement over several days, with freedom of movement for the patient without operator attention and with improved stability of the electrode, which minimizes the drift artifacts previously encountered. These improvements will facilitate routine clinical monitoring of tissue oxygen tension.
Wireless communications has more to offer for spacecraft avionics than just reduced mass and spac... more Wireless communications has more to offer for spacecraft avionics than just reduced mass and space. A team at NASA Ames Research Center (ARC) is actively involved in designing and implementing wireless systems, and is part of a multi-center NASA effort to investigate wireless sensor networks (WSN) for spacecraft sponsored by the NASA Engineering and Safety Center. In this paper, we
Advances in experimental medicine and biology, 1988
Our new method is comparable to the standard, "open-end" tonometer system and incorpora... more Our new method is comparable to the standard, "open-end" tonometer system and incorporates all its abilities to monitor oxygen tension and perfusion. The new device has the advantage of being completely sealed, providing a true, continuous direct measurement over several days, with freedom of movement for the patient without operator attention and with improved stability of the electrode, which minimizes the drift artifacts previously encountered. These improvements will facilitate routine clinical monitoring of tissue oxygen tension.
Revolutionary capabilities for robust control of inflatable Lunar and Martian transit vehicles an... more Revolutionary capabilities for robust control of inflatable Lunar and Martian transit vehicles and planetary habitats can be developed using advanced wireless network technology and modular avionics coupled with facile human to system interfaces. Fully wireless modular avionics would eliminate any cabling associated with power and data transmission, allowing easy deployment of flexible control systems and human interfaces. Furthermore, wearable human interface systems hosting virtual reality interaction methods can provide significant improvement in human situational awareness and control of dynamic space systems. The crew can interact with intelligent software agents providing human-like interaction using speech. These advanced information management systems would incorporate intelligent software agents to assist the crew in performing vehicle and mission operations. Advances in robust wireless data communications and wireless power transmission are the key technologies that enable...
The Intelligent Mobile Technologies (IMT) group at NASA Ames Research Center is developing new te... more The Intelligent Mobile Technologies (IMT) group at NASA Ames Research Center is developing new technologies that may be useful in supplementing the International Space Station (ISS) data system. The crewmembers would like to have a capability for easily displaying ...
As the technology matures, wireless networks are being used in more applications providing signif... more As the technology matures, wireless networks are being used in more applications providing significant benefits to mobile users. There are now many products, complying with wireless network standards 802.11 and 802.11b, for linking mobile computing elements together and into the Internet using radio signals. Wireless networks provide mobility, but offer lower reliability and performance compared to wired networks. Standard methods
Canada contains a unique site for possible analogue studies of Mars, from Mars-related science to... more Canada contains a unique site for possible analogue studies of Mars, from Mars-related science to studies of technologies that may be used for robotic and human exploration of other planets. This is the Haughton Crater, on Devon Island, Nunavut, in the ...
Mobile Agents (MA) is an advanced Extra-Vehicular Activity (EVA) communications and computing sys... more Mobile Agents (MA) is an advanced Extra-Vehicular Activity (EVA) communications and computing system to increase astronaut self-reliance and safety, reducing dependence on continuous monitoring and advising from mission control on Earth. MA is voice controlled and provides information verbally to the astronauts through programs called “personal agents.” The system partly automates the role of CapCom in Apollo-including monitoring and managing navigation, scheduling, equipment deployment, telemetry, health tracking, ...
ABSTRACT Heterogeneous Spacecraft Networks (HSNs) are network environments in which spacecraft fr... more ABSTRACT Heterogeneous Spacecraft Networks (HSNs) are network environments in which spacecraft from different missions and institutions can communicate with each other at low cost and with low impact on overall system resources. The Mission Design Center (MDC) at NASA Ames Research Center has been studying solutions for low cost multi-spacecraft systems for a number of years. One may now build on the idea to interconnect clusters of spacecraft with each other to have them act as mobile nodes belonging to the same collaborative mission. Recent progress in small satellite technology is significant, and one of the advantages of small satellites lies precisely in the large quantity of spacecraft that can be produced at accessible costs. It follows naturally that small satellites are an interesting candidate platform for development and demonstration of the HSN concept. This paper is the second in a series of three companion papers. The general concept of operations for HSNs in LEO and a number of future applications are proposed in the first paper [6], while enabling technology such as devices and lower layer protocols are discussed in paper three [7]. In this paper, we pick up the scenario of a low-cost and multi-institutional network of Earth Observation (EO) missions in LEO and conduct network performance analysis using the AGI System Tool Kit (STK) and the open-source Network Simulator (NS-3). A multi-spacecraft network consolidates the individual capabilities of each spacecraft from different institutions by combining benefits of both frequent revisit and concentrated observation. Complementary and correlated data could be collected simultaneously from a large set of distributed spacecraft utilizing HSN capability. In this specific configuration, communication distance between spacecraft, related delays and error rate are the major factors in network performance. Also, average duration of communication opportunities between spacecraft is usually very limited. Thus, it is i- portant to simulate orbital dynamics, link margins, and protocols simultaneously to analyze network performances. In this paper, we compare some existing protocols to obtain a measure for the practical performance of the candidate network. We focus on best-effort data delivery, an approach necessitated by the severe constraints on communications resulting from low-cost and low system resource small spacecraft. In the application layer, we show that packet size and data rate of a source node also affect overall performance of the network. We present the resulting figures of merit from our simulations. The paper concludes with a summary of the simulation results.
Abstract-Future human planetary exploration field teams will need daily communications with their... more Abstract-Future human planetary exploration field teams will need daily communications with their base and with mission control. A remote field wireless digital network will be a requirement for safe and productive human exploration. Proper selection of radio-frequency hardware ...
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