A multi-objective synthesis problem involvingH2, H∞ and impulse-to-peak performances is investigated. In general, multi-objective control problems are hard problems to solve and do not have exact solutions. Here, an LMI formulation is proposed for the mixedH2/impulseto-peak optimization under an H∞ constraint for LTI discrete-time systems. This framework is then used to control the attitude of ...

Moments before the launch of every space vehicle, engineering discipline specialists must make a critical go/no-go decision. The cost of a false positive, allowing a launch in spite of a fault, or a false negative, stopping a potentially successful launch, can be measured in the tens of millions of dollars, not including the cost in morale and other more intangible detriments. The Aerospace Cor...

Ice/frost formation on the Space Shuttle cryogenic propel 1 ant tanks presents a different problem from that of past launch vehicles. Lift off weight addition has been the primary concern on past launch vehicles. The primary ice/frost concern on the Shuttle vehicle is damage to the Orbiter Thermal Protection System due to ice/frost impact. The approach used to arrive at a solution to this uni­ ...

Laboratories throughout the world are rapidly gaining atomically precise control over matter. As this control extends to an ever wider variety of materials, processes and devices, opportunities for applications relevant to NASA's missions will be created. This document surveys a number of future molecular nanotechnology capabilities of aerospace interest. Computer applications, launch vehicle i...

A new approach is proposed incorporating heuristic optimization algorithm with a switch to a local search algorithm for the multidisciplinary design of solid launch vehicle at conceptual level. Heuristic optimization algorithms such as Genetic Algorithm often may locate near optimum solutions at the expense of large function evaluations. Local search algorithms including both gradient and non g...

The goal of the NASA Reusable Launch Vehicle (RLV) technology program is to develop and demonstrate essential, cost-effective technologies for next-generation launch systems. The XÐ33 flight vehicle presently being developed by Lockheed-Martin is an experimental Single-Stage-to-Orbit (SSTO) demonstrator that is intended to validate critical technologies for the full-scale RLV. One of the key te...