A possible next-generation launch vehicle may be a fully reusable, single-stage-to-orbit (SSTO) aerospacecraft. This class of hypersonic vehicle includes highly integrated airframe and propulsion systems, hence fuel-optimal trajectories are of special interest. Also, since these vehicles are neither conventional aircraft nor rockets, the appropriate approach for trajectory analysis during preli...

Health diagnostics is an area where major improvements have been identified for potential implementation into the design of new reusable launch vehicles in order to reduce life-cycle costs, to increase safety margins, and to improve mission reliability. NASA Ames is leading the effort to advance inspection and health management technologies for thermal protection systems. This paper summarizes ...

In the application of adaptive flight control, significant issues arise due to limitations in the plant inputs, such as: actuator displacement limits, actuator rate limits, linear input dynamics, and time delay. A method is introduced that allows an adaptive law to be designed for the system without these input characteristics, and then to be applied to the system with these characteristics, wi...

Over the past decade, the NASA Langley Research Center developed a series of "grand challenge" applications demonstrating the use of parallel and distributed computation and multidisciplinary design optimization. All but the last of these applications were focused on the high-speed civil transport vehicle; the final application focused on reusable launch vehicles. Teams of discipline experts de...

Analysis of variance (ANOVA) and self-organizing map (SOM) were applied to data mining for aerodynamic design space. These methods make it possible to identify the effect of each design variable on objective functions. ANOVA shows the information quantitatively, while SOM shows it qualitatively. Furthermore, ANOVA can show the effects of interaction between design variables on objective functio...

The Space Launch System is a Shuttle-derived heavy-lift vehicle currently in development to serve as NASA’s premiere launch vehicle for space exploration. The Space Launch System is a multistage rocket with two Solid Rocket Boosters and multiple payloads, including the Multi-Purpose Crew Vehicle. Planned Space Launch System destinations include near-Earth asteroids, the Moon, Mars, and Lagrange...

Collaborative optimization is a new design architecture speci cally created for large-scale distributed-analysis applications. In this approach, a problem is decomposed into a user-de ned number of subspace optimization problems that are driven towards interdisciplinary compatibility and the appropriate solution by a system-level coordination process. This decentralized design strategy allows d...

Abstract In this paper, the ascent trajectory optimization of a lifting body Single-Stage To Orbit (SSTO) reusable launch vehicle is investigated. The work carried out using Direct Multiple Shooting method to solve Optimal Control problem. crucial initialisation optimisation process performed by combination two evolutionary algorithms, namely Multi-Objective Parzen-based Estimation Distribution...

Abstract In the last decade, rapid and successful development of reusable launch systems such as SpaceX’ Falcon 9 demonstrated both operational feasibility launchers their economic viability. The objective recovering a launcher or launcher’s booster requires to safely return vehicle from orbital sub-orbital conditions soft landing. To increase reusability, decrease turnaround time reduce costs,...

BACKGROUND Round ligament varices (RLV) are rare and are almost exclusively seen in pregnant women. RLV may clinically resemble an inguinal hernia, inguinal mass, or other pathology involving the inguinal canal and round ligament. Ultrasound imaging is important to make the diagnosis of RLV. CASE REPORT A 34-year-old Hispanic woman, gravida 1 para 0, at 34 weeks gestation, presented to our outp...