Abstract: Two algorithms are disclosed that, with the use of a 3-axis accelerometer, will be able to determine the angles of attack, sideslip and roll of a capsule-type spacecraft prior to entry (at very high altitudes, where the atmospheric density is still very low) and during entry. The invention relates to emergency situations in which no reliable attitude and attitude rate are available. Provided that the spacecraft would not attempt a guided entry without reliable attitude information, the objective of the entry system in such case would be to attempt a safe ballistic entry. A ballistic entry requires three controlled phases to be executed in sequence: First, cancel initial rates in case the spacecraft is tumbling; second, maneuver the capsule to a heat-shield-forward attitude, preferably to the trim attitude, to counteract the heat rate and heat load build up; and third, impart a ballistic bank or roll rate to null the average lift vector in order to prevent prolonged lift down situations.
Abstract: Disclosed are methods for isolating and purifying single wall carbon nanotubes from contaminant matrix material, methods for forming arrays of substantially aligned nanotubes, and products and apparatus comprising a plurality of nanotube structures.
Type:
Grant
Filed:
January 23, 2007
Date of Patent:
July 27, 2010
Assignee:
GB Tech, Inc.
Inventors:
Pavel Nikolaev, Sivaram Arepalli, Mark S. F. Clarke, Daniel L. Feeback
Abstract: Disclosed are methods for isolating and purifying single wall carbon nanotubes from contaminant matrix material, methods for forming arrays of substantially aligned nanotubes, and products and apparatus comprising a plurality of nanotube structures.
Type:
Grant
Filed:
July 9, 2002
Date of Patent:
January 23, 2007
Assignee:
GB Tech, Inc.
Inventors:
Pavel Nikolaev, Sivaram Arepalli, Mark S. F. Clarke, Daniel L. Feeback
Abstract: Disclosed are methods for isolating and purifying single wall carbon nanotubes from contaminant matrix material, methods for forming arrays of substantially aligned nanotubes, and products and apparatus comprising a plurality of nanotube structures.
Type:
Application
Filed:
July 9, 2002
Publication date:
September 11, 2003
Applicant:
GB Tech, Inc.
Inventors:
Pavel Nikolaev, Sivaram Arepalli, Mark S.F. Clarke, Daniel L. Feeback