Engineering topics

Sinclair, Robert

Publications and source records attributed to Sinclair, Robert.

22 records · Page 2

DOE OSTI2018

In-situ visualization of solute-driven phase coexistence within individual nanorods

Nanorods are promising components of energy and information storage devices that rely on solute-driven phase transformations, due to their large surface-to-volume ratio and ability to accommodate strain. Here we investigate the hydrogen-induced phase transition in individual penta-twinned palladium nanorods of varying aspect ratios with ~3 nm spatial resolution to understand the correlation between nanorod structure and thermodynamics. We find that the hydrogenated phase preferentially nucleates at the rod tips, progressing along the length of the nanorods with increasing hydrogen pressure. While nucleation pressure is nearly constant for all lengths, the number of phase boundaries is length-dependent, with stable phase coexistence always occurring for rods longer than 55 nm. Moreover, such coexistence occurs within individual crystallites of the nanorods and is accompanied by defect formation, as supported by in situ electron microscopy and elastic energy calculations. In conclusion, these results highlight the effect of particle shape and dimension on thermodynamics, informing nanorod design for improved device cyclability.

25 ENERGY STORAGE↗

NASA NTRS2011

The Orion Pad Abort 1 Flight Test A Highly Successful Test

The Orion Pad Abort 1 (PA-1) flight test was designed as an early demonstration of the Launch Abort System (LAS) for the Orion capsule. The LAS was designed developed and manufactured by the Lockheed Martin/Orbital Sciences team. At inception it was realized that recovery of the Orion Capsule simulator would be useful from an engineering analysis and data recovery point of view. Additionally this test represented a flight opportunity for the Orion parachute system, which in a real abort would provide final landing deceleration. The Orion parachute program is named CPAS (CEV Parachute Assembly System). Thus CPAS became a part of the PA-1 flight, as a secondary test objective. At program kick off, the CPAS system was in the design state described below. Airbag land landing of the spacecraft was the program baseline. This affected the rigging of the parachutes. The system entry deployment conditions and vehicle mass have both evolved since that original design. It was decided to use the baseline CPAS Generation 1 (Gen 1) parachute system for the recovery of the PA-1 flight. As CPAS was a secondary test objective, the system would be delivered in its developmental state. As the PA-1 program evolved, the parachute recovery system (CPAS) moved from a secondary objective to a more important portion of the program. Tests were added, weights and deployment conditions changed and some hardware portions of the CPAS configuration were not up to the new challenges. Additional tests were added to provide confidence in the developmental system. This paper will review a few of these aspects with the goal of showing some preliminary and qualitative results from what we believe was a highly successful test.

Sinclair, Robert↗

NASA NTRS2009

Development and Testing of the Orion CEV Parachute Assembly System (CPAS)

The Crew Exploration Vehicle (CEV) is an element of the Constellation Program that includes launch vehicles, spacecraft, and ground systems needed to embark on a robust space exploration program. As an anchoring capability of the Constellation Program, the CEV shall be human-rated and will carry human crews and cargo from Earth into space and back again. Coupled with transfer stages, landing vehicles, and surface exploration systems, the CEV will serve as an essential component of the architecture that supports human voyages to the Moon and beyond. In addition, the CEV will be modified, as required, to support International Space Station (ISS) mission requirements for crewed and pressurized cargo configurations. Headed by Johnson Space Center (JSC), NASA selected Jacobs Engineering as the support contractor to manage the overall CEV Parachute Assembly System (CPAS) program development. Airborne Systems was chosen to develop the parachute system components. General Dynamics Ordnance and Tactical Systems (GD-OTS) was subcontracted to Airborne Systems to provide the mortar systems. Thus the CPAS development team of JSC, Jacobs, Airborne Systems and GD-OTS was formed. The CPAS team has completed the first phase, or Generation I, of the design, fabrication, and test plan. This paper presents an overview of the CPAS program including system requirements and the development of the second phase, known as the Engineering Development Unit (EDU) architecture. We also present top level results of the tests completed to date. A significant number of ground and flight tests have been completed since the last CPAS presentation at the 2007 AIAA ADS Conference.

Lichodziejewski, David↗

NASA NTRS2008

A Status Report on the Parachute Development for NASA's Next Manned Spacecraft

NASA has determined that the parachute portion of the Landing System for the Crew Exploration Vehicle (CEV) will be Government Furnished Equipment (GFE). The Earth Landing System has been designated CEV Parachute Assembly System (CPAS). Thus a program team was developed consisting of NASA Johnson Space Center (JSC) and Jacobs Engineering through their Engineering and Science Contract Group (ESCG). Following a rigorous competitive phase, Airborne Systems North America was selected to provide the parachute design, testing and manufacturing role to support this team. The development program has begun with some early flight testing of a Generation 1 parachute system. Future testing will continue to refine the design and complete a qualification phase prior to manned flight of the spacecraft. The program team will also support early spacecraft system testing, including a Pad Abort Flight Test in the Fall of 2008

Sinclair, Robert↗