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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 1,693 records · Page 94
All sourcesNASA NTRSDOE OSTI
NASA NTRS1999

Autonomous Science Decisions for Mars Sample Return

In the near future NASA intends to explore Mars in preparation for a sample return mission using robotic devices such as landers rovers, orbiters, airplanes, and/or balloons. Such platforms will likely carry imaging devices to characterize the surface morphology, and a variety of analytical instruments intended to evaluated the chemical and mineralogical nature of the environment(s) that they encounter. Historically, mission operations have involved the following sequence of activities: (1) return of scientific data from the vehicle; (2) evaluation of the data by space scientists; (3) recommendations of the scientists regarding future mission activity; (4) transmission of commands to the vehicle to achieve this activity; and (5) new activity by the vehicle in response to those commands.

Roush, T. L.↗
NASA NTRS2000

Robust Inversion and Data Compression in Control Allocation

We present an off-line computational method for control allocation design. The control allocation function delta = F(z)tau = delta (sub 0) (z) mapping commanded body-frame torques to actuator commands is implicitly specified by trim condition delta (sub 0) (z) and by a robust pseudo-inverse problem double vertical line I - G(z) F(z) double vertical line less than epsilon (z) where G(z) is a system Jacobian evaluated at operating point z, z circumflex is an estimate of z, and epsilon (z) less than 1 is a specified error tolerance. The allocation function F(z) = sigma (sub i) psi (z) F (sub i) is computed using a heuristic technique for selecting wavelet basis functions psi and a constrained least-squares criterion for selecting the allocation matrices F (sub i). The method is applied to entry trajectory control allocation for a reusable launch vehicle (X-33).

Hodel, A. Scottedward↗
NASA NTRS2000

STS-106 Crew Activities Report/Flight Day 04 Highlights

On this fourth day of the STS-106 Atlantis mission, the flight crew, Commander Commander Terrence W. Wilcutt, Pilot Scott D. Altman, and Mission Specialists Daniel C. Burbank, Edward T. Lu, Richard A. Mastracchio, Yuri Ivanovich Malenchenko, and Boris V. Morukov are seen preparing for the scheduled space walk. Lu and Malenchenko are seen coming through the hatch of the International Space Station (ISS). Also shown are Lu and Malenchenko attaching a magnetometer and boom to Zvezda. Mastracchio operates the robot arm moving the extravehicular activity (EVA) crew outside of the ISS.

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NASA NTRS2000

STS-106 Crew Activities Report/Flight Day 06 Highlights

On this sixth day of the STS-106 Atlantis mission, the flight crew, Commander Commander Terrence W. Wilcutt, Pilot Scott D. Altman, and Mission Specialists Daniel C. Burbank, Edward T. Lu, Richard A. Mastracchio, Yuri Ivanovich Malenchenko, and Boris V. Morukov are seen participating in several outfitting and transferring activities. Burbank and Morukov replace batteries in Zarya, while Lu and Malenchenko install three batteries and electrical equipment inside the Zvezda Service Module. Footage of Wilcutt participating in an interview concludes the events of the day.

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NASA NTRS2000

STS-106 Crew Activities Report/Flight Day 07 Highlights

On this seventh day of the STS-106 Atlantis mission, the flight crew, Commander Commander Terrence W. Wilcutt, Pilot Scott D. Altman, and Mission Specialists Daniel C. Burbank, Edward T. Lu, Richard A. Mastracchio, Yuri Ivanovich Malenchenko, and Boris V. Morukov are seen participating in several outfitting activities. Burbank and Morukov remove and replace a fourth battery in Zarya. Lu and Malenchenko finish installing the third and final battery and other electrical equipment inside the Zvezda Service Module. While Altman and Wilcutt perform a series of jet firings, Altman is shown as he narrates a tour of the Zvezda Service Module. Scenes also include Lu and Malenchenko unpacking the Russian-made Orlan space suits, Burbank and Wilcutt participating in an interview, and a beautiful night shot of the International Space Station (ISS) and Atlantis complex above the Earth.

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NASA NTRS1999

Evolution of International Space Station GN&C System Across ISS Assembly Stages

The Guidance Navigation and Control (GN&C) system for the International Space Station is initially implemented by the Functional Cargo Block (FGB) which was built by the Khrunichev Space Center under direct contract to Boeing. This element (Stage 1A/R) was launched on 20 November 1998 and is currently operating on-orbit. The components and capabilities of the FGB Motion Control System (MCS) are described. The next ISS element, which has GN&C functionality will be the Service Module (SM) built by Rocket Space Corporation-Energia. This module is scheduled for launch (Stage 1R) in early 2000. Following activation of the SM GN&C system, the FGB MCS is deactivated and no longer used. The components and capabilities of the SM GN&C system are described. When a Progress vehicle is attached to the ISS it can be used for reboost operations, based on commands provided by the Mission Control Center-Moscow. When a data connection is implemented between the SM and the Progress, the SM can command the Progress thrusters for attitude control and reboosts. On Stage 5A, the U.S. GN&C system will become activated when the U.S. Laboratory is de loyed and installed (launch schedule is currently TBD). The U.S. GN&C system provides non-propulsive control capabilities to support micro-gravity operations and minimize the use of propellant for attitude control, and an independent capability for determining the ISS state vector, attitude, attitude rate. and time.. The components and capabilities of the U.S. GN&C system are described and the interactions between the U.S. and Russian Segment GN&C systems are also described.

Lee, Roscoe↗
NASA NTRS1992

STS-50 Crew Arrival

The crew of STS-50, Commander Richard N. Richards, Pilot Kenneth D. Bowersox, Payload Commander Bonnie J. Dunbar, Mission Specialists Ellen S. Baker and Carl J. Meade, and Payload Specialists Lawrence J. DeLucas and Eugene H. Trinh are seen landing four T-38 aircraft at Kennedy Space Center for a terminal countdown and demonstration test.They are introduced by Richards and each makes a brief statement about his or her expectations for the upcoming Columbia mission.

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NASA NTRS2000

STS-106 Crew Activities Report/Flight Day 9 Highlights

On this ninth day of the STS-106 Atlantis mission, the flight crew, Commander Commander Terrence W. Wilcutt, Pilot Scott D. Altman, and Mission Specialists Daniel C. Burbank, Edward T. Lu, Richard A. Mastracchio, Yuri Ivanovich Malenchenko, and Boris V. Morukov are shown transferring supplies and equipment. Equipment includes an exercise treadmill, for use by the first resident crew. Altman, Lu, Burbank and Morukov are seen installing the treadmill in the Zvezda module. Footage also shows Lu and Altman participating in a telecommunication interview. A beautiful night shot of the International Space Station (ISS) and Atlantis complex above the Earth is also shown.

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NASA NTRS2000

STS-106 Crew Activities Report/Flight Day 10 Highlights

On this tenth day of the STS-106 Atlantis mission, the flight crew, Commander Commander Terrence W. Wilcutt, Pilot Scott D. Altman, and Mission Specialists Daniel C. Burbank, Edward T. Lu, Richard A. Mastracchio, Yuri Ivanovich Malenchenko, and Boris V. Morukov are shown preparing for their departure from the International Space Station (ISS). Crewmembers are shown closing the hatches of the Zarya, Unity and Zvezda modules. They are also shown packing up trash and packing materials into the Russian Progress ship.

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NASA NTRS1997

Multi-Window Controllers for Autonomous Space Systems

Multi-window controllers select between elementary linear controllers using nonlinear windows based on the amplitude and frequency content of the feedback error. The controllers are relatively simple to implement and perform much better than linear controllers. The commanders for such controllers only order the destination point and are freed from generating the command time-profiles. The robotic missions rely heavily on the tasks of acquisition and tracking. For autonomous and optimal control of the spacecraft, the control bandwidth must be larger while the feedback can (and, therefore, must) be reduced.. Combining linear compensators via multi-window nonlinear summer guarantees minimum phase character of the combined transfer function. It is shown that the solution may require using several parallel branches and windows. Several examples of multi-window nonlinear controller applications are presented.

Lurie, B, J.↗
NASA NTRS1997

A Long Range Science Rover For Future Mars Missions

This paper describes the design and implementation currently underway at the Jet Propulsion Laboratory of a long range science rover for future missions to Mars. The small rover prototype, called Rocky 7, is capable of long traverse. autonomous navigation. and science instrument control, carries three science instruments, and can be commanded from any computer platform and any location using the World Wide Web. In this paper we describe the mobility system, the sampling system, the sensor suite, navigation and control, onboard science instruments. and the ground command and control system.

Hayati, Samad↗
NASA NTRS2000

STS-97 Crew Activity Report/Flight Day 10 Highlights

On this tenth day of the STS-97 mission, Commander Brent W. Jett, Pilot Michael J. Bloomfield, and Mission Specialists Joseph R. Tanner, Carlos I. Noriega, and Marc Garneau are seen saying good-bye to the International Space Station's (ISS's) resident crew (Commander Bill Shepherd, Pilot Yuri Gidzenko and Flight Engineer Sergei Krikalev) and sealing the hatches between the Endeavour Orbiter and the ISS. Footage shows the ISS against a rotating Earth as it passes over China.

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NASA NTRS2000

STS-97 Crew Activity Report/Flight Day 9 Highlights

On this ninth day of the STS-97 mission, Commander Brent W. Jett, Pilot Michael J. Bloomfield, and Mission Specialists Joseph R. Tanner, Carlos I. Noriega, and Marc Garneau are shown meeting the resident International Space Station (ISS) crew (Commander Bill Shepherd and Cosmonauts Yuri Gidzenko and Sergei Krikalev) for the first time. The two crews answer questions about the ISS and future missions, and what it is like living on the ISS.

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NASA NTRS2000

Emergency Multiengine Aircraft System for Lateral Control Using Differential Thrust Control of Wing Engines

Development of an emergency flight control system is disclosed for lateral control using only differential engine thrust modulation of multiengine aircraft is currently underway. The multiengine has at least two engines laterally displaced to the left and right from the axis of the aircraft. In response to a heading angle command psi(sub c) is to be tracked. By continually sensing the heading angle psi of the aircraft and computing a heading error signal psi(sub e) as a function of the difference between the heading angle command psi(sub c) and the sensed heading angle psi, a track control signal is developed with compensation as a function of sensed bank angle phi. Bank angle rate phi, or roll rate p, yaw rate tau, and true velocity produce an aircraft thrust control signal ATC(sub psi(L,R)). The thrust control signal is differentially applied to the left and right engines, with equal amplitude and opposite sign, such that a negative sign is applied to the control signal on the side of the aircraft. A turn is required to reduce the error signal until the heading feedback reduces the error to zero.

Burken, John J.↗
NASA NTRS1993

STS-56 Astronaut Crew Arrival at KSC for Launch

The crew of STS-56, Commander Kenneth D. Cameron, Pilot Stephen S. Oswald, and Mission Specialists C. Michael Foale Ph.D., Kenneth D. Cockrell, and Ellen Ochoa, is seen arriving and disembarking from T-38 aircraft. Commander Cameron introduces the crew and each member gives a brief statement about the mission.

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NASA NTRS1993

STS-56 Atlas-2/TCDT Activities

The crew of STS-56, Commander Kenneth D. Cameron, Pilot Stephen S. Oswald, and Mission Specialists C. Michael Foale Ph.D., Kenneth D. Cockrell, and Ellen Ochoa are seen landing the T-38 aircraft as part of the terminal countdown and demonstration test (TCDT). The crew is introduced by Commander Cameron and each member gives a brief statement about the upcoming mission and answers questions from the press. The crew is seen during various stages of training, including emergency egress training.

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NASA NTRS1992

STS-50 Crew Briefing

Commander Richard N. Richards introduces the crew of STS-50, Pilot Kenneth D. Bowersox, Payload Commander Bonnie J. Dunbar, Mission Specialists Ellen S. Baker and Carl J. Meade, and Payload Specialists Lawrence J. DeLucas and Eugene H. Trinh, in a preflight conference. Each crew member gives an overview of the mission's activities, objectives, and payload (USML-01), and answers questions from the press.

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NASA NTRS1993

STS-55 Emergency Egress Training/Photo Opportunity at Pad A

The crew of STS-55, Commander Steven R. Nagel, Pilot Terence T. Henricks, Mission Specialists Jerry L. Ross, Charles J. Precourt, and Dr. Bernard A. Harris Jr., and Payload Specialists Dr. Ulrich Walter and Hans Schlegel are seen during emergency egress training. Then Commander Nagel introduces the members of the crew and they each give a brief statement about the mission and answer questions from the press.

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