Search NASA⌕ Search

SEARCH · Search NASA

Results for “Shuttle Payload Loads”

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.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1980

A survey of load methodologies for shuttle orbiter payloads

Loads methods currently being used to design shuttle orbiter payloads are summarized. Methods used for the design of payloads launched by expendable launch vehicles are described in historical perspective. Experiences gained from expendable launch vehicle payloads are used to develop methodologies for the space shuttle orbiter payloads. The objectives for the development of a new methodology for the shuttle payloads are to reduce the cost and schedule for the payload load analysis by decoupling the payload analysis from the launch vehicle to the maximum extent possible. Methods are described for payload member load estimation or obtaining upper bounds for dynamic loads, as well as load prediction or calculating actual transient member load time histories.

Chen, J. C.↗
NASA NTRS1981

A survey of load methodologies for shuttle orbiter payloads

Loads methods currently being used to design planetary spacecraft to be launched on the shuttle orbiter are summarized. Experiences gained from expendable launch vehicle payloads are used to develop methodologies for the space shuttle orbiter payloads. The objectives for the development of a new methodology for the shuttle payloads are to reduce the cost and schedule for the payload load analysis by decoupling the payload analysis from the launch vehicle to the maximum extent possible. Methods are described for payload member load estimation or obtaining upper bounds for dynamic loads, as well as load prediction or calculating actual transient member load time histories.

Chen, J. C.↗
NASA NTRS2011

Lessons Learned from Shuttle Payload Verification Loads Analysis

When a system experiences a loading environment characterized by rapidly varying forces, such as a rocket launch, a transient analysis is used to analyze the response of the system. The most common transient analysis methodology is the Coupled Loads Analysis (CLA). CLAs are used by the automotive and aerospace industry to analyze cars, trucks, planes, helicopters, spacecraft, etc. The Space Shuttle program also uses the CLA methodology to assess the compatibility of the payload with the Orbiter and the flight environment. The Space Shuttle Verification Loads Analysis (VLA) was a standardized process that started between ten and thirteen months prior to launch, and included several meetings as well as analysis by both the Shuttle Program and the payload developers. Over the course of the Space Shuttle Program, many improvements were made to the process which helped to reduce cycle time and improve manifest flexibility. There were also several issues which were never properly addressed, but a work-around would be developed to keep the process flowing. The lessons learned included automation of some processes and standardization of others, early assessments, improved documentation and better coordination with all stakeholders in the process. Lessons learned also included the limitations in the current process, and what needs to be planned for in the future to avoid the same issues.

Bruno, Erica↗
NASA NTRS1992

Coupled loads analysis for Space Shuttle payloads

Described here is a method for determining the transient response of, and the resultant loads in, a system exposed to predicted external forces. In this case, the system consists of four racks mounted on the inside of a space station resource node module (SSRNMO) which is mounted in the payload bay of the space shuttle. The predicted external forces are forcing functions which envelope worst case forces applied to the shuttle during liftoff and landing. This analysis, called a coupled loads analysis, is used to couple the payload and shuttle models together, determine the transient response of the system, and then recover payload loads, payload accelerations, and payload to shuttle interface forces.

Eldridge, J.↗
NASA NTRS1989

Efficient loads analyses of Shuttle-payloads using dynamic models with linear or nonlinear interfaces

An efficient method for the load analysis of Shuttle-payload systems with linear or nonlinear attachment interfaces is presented which allows the kinematics of the interface degrees of freedom at a given time to be evaluated without calculating the combined system modal representation of the Space Shuttle and its payload. For the case of a nonlinear dynamic model, an iterative procedure is employed to converge the nonlinear terms of the equations of motion to reliable values. Results are presented for a Shuttle abort landing event.

Spanos, P. D.↗
NASA NTRS1981

System analysis approach to deriving design criteria (loads) for Space Shuttle and its payloads. Volume 1: General statement of approach

Space shuttle, the most complex transportation system designed to date, illustrates the requirement for an analysis approach that considers all major disciplines simultaneously. Its unique cross coupling and high sensitivity to aerodynamic uncertainties and high performance requirements dictated a less conservative approach than those taken in programs. Analyses performed for the space shuttle and certain payloads, Space Telescope and Spacelab, are used a examples. These illustrate the requirements for system analysis approaches and criteria, including dynamic modeling requirements, test requirements control requirements and the resulting design verification approaches. A survey of the problem, potential approaches available as solutions, implications for future systems, and projected technology development areas are addressed.

Ryan, R. S.↗
NASA NTRS1981

System analysis approach to deriving design criteria (Loads) for Space Shuttle and its payloads. Volume 2: Typical examples

The achievement of an optimized design from the system standpoint under the low cost, high risk constraints of the present day environment was analyzed. Space Shuttle illustrates the requirement for an analysis approach that considers all major disciplines (coupling between structures control, propulsion, thermal, aeroelastic, and performance), simultaneously. The Space Shuttle and certain payloads, Space Telescope and Spacelab, are examined. The requirements for system analysis approaches and criteria, including dynamic modeling requirements, test requirements, control requirements, and the resulting design verification approaches are illustrated. A survey of the problem, potential approaches available as solutions, implications for future systems, and projected technology development areas are addressed.

Ryan, R. S.↗
NASA NTRS1971

NASA/DOD earth orbit shuttle traffic models based on side by side loading of payloads

An analysis of the spacecraft configurations and space missions for the Earth Orbit Shuttle traffic model based on side-by-side loading of payloads is presented. The reusable tugs to be employed for the mission are examined. The space missions are described with respect to the following: (1) number of Earth Orbit Shuttle flights by inclination, (2) total payloads to orbit, (3) energy states required, and (4) characteristics of reusable tug.

Kincade, R. E.↗
NASA NTRS1971

NASA/DOD earth orbit shuttle traffic models based on end to end loading of payloads

An analysis of the spacecraft configurations and space missions for the Earth Orbit Shuttle traffic model based on an end-to-end loading of payloads is presented. Two possible reusable tugs are considered. The space missions are described with respect to the following: (1) number of earth orbit shuttle flights by inclination, (2) total payloads to orbit, (3) energy stages required, and (4) characteristics of reusable tug.

Kincade, R. E.↗
NASA NTRS1983

Loads environment for payload/cargo integration

Space Shuttle users are required to design their payload to the Shuttle loads environment. This loads environment covers mission phases from prelaunch to landing. Transient response loads analyses are required for lift-off and landing events. Other mission events are analyzed statically because they result in payload loads that either change slowly or are lower than lift-off and landing loads. Response data from flight instrumentation located on the orbiter and payloads have been compared to preflight design conditions and to nominal predictions. The results have verified that the design loads envelop flight responses.

Frederick, D. H.↗
NASA NTRS1988

A mass additive technique for modal testing as applied to the Space Shuttle ASTRO-1 payload

Traditionally, a fixed base modal test has been performed as a means of verifying the coupled loads math model for Space Shuttle flight payloads. An alternate method, a free-free configured payload using mass loaded boundary conditions, is presented as a means of verifying the coupled loads model of the ASTRO-1 flight payload. This method allows evaluation of the influence of local load paths into the frequency range of the free-free test. The method is cost effective and does not contaminate the modal test results with fixture coupled modes or boundary condition uncertainties. This paper describes the mass additive modal test technique as applied to the Space Shuttle ASTRO-1 flight payload.

Coleman, A. D.↗
NASA NTRS2016

Tethered Space Satellite-1 (TSS-1): Wound About a Bolt

In the early 1990's US and Italian scientists collaborated to study the electrodynamics on a long tether between two satellites as it moved through the electrically charged portion of Earth's atmosphere called the ionosphere. Potential uses for the electrical current induced in the long wire include power and thrust generation for a satellite, momentum exchange, artificial gravity, deployment of sensors or antennas, and gravity-gradient stabilization. The Tethered Space Satellite (TSS) was a first-of-its-kind experiment with long tethers in space. It consisted of a satellite with science experiments attached to a 12.5 mile long, very thin (0.10 inch diameter) copper wire assembly wound around a spool in the deployer reel mechanism. The whole mechanism sits on a pallet that is installed into the Shuttle bay. At an altitude of 160 nautical miles above earth, the satellite would be deplodeployed from the Shuttle bay by raising it on a boom facing away from Earth. Once cleared of the bay, the deployer mechanism would slowly feed out the 12-plus miles of tether. Scientific data would be collected throughout the operation, after which the satellite would be reeled back in. A receiver spool to catch the 12.5 mile tether as it was being unwound by the deployer reel mechanism was set up to do the system-level test of deployer real mechanism prior to installing the loaded pallet into the Shuttle bay. The system level tests were required before the pallet could be installed into the Space Shuttle cargo bay. A few months before flight, the system level tests, including unreeling and reeling the tether, were completed at Kennedy Space Center (KSC) and the TSS payload was installed onto the Spacelab pallet. Some of this testing equipment was then shipped back to the contractor, Martin Marietta. Integration with the Shuttle began. Systems-level load analyses, which cannot be run until all information about each payload is finalized, was run in parallel with the physical integration of the hardware into the Shuttle payload bay. An analysis, called Coupled loads analysis, incorporates any updates to the model due to system level tests of all the different payloads, and any changes that were found during integration. Engineering analysis examines the worst case scenarios for the loads the hardware will see. The two times during the mission where the dynamic loads are the worst were 1) the first 10-second portion of Shuttle lift off, and 2) a 2-second time during landing when the landing gears hit the ground. The coupled loads analysis using the final verification loads showed that a single bolt attaching the deployer reel mechanism to the support structure had a "negative margin" - which is an indication that it might fail - during touch down. Hardware certification rules do not allow for hardware to fly with negative margins. A structural failure of one payload could have serious or catastrophic consequences to other payloads, or may significantly damage the Orbiter. The issue had to be resolved before the flight.

O'Connor, Brian↗
NASA NTRS1999

Evaluation of MPLM Design and Mission 6A Coupled Loads Analyses

Through the development of a space shuttle payload, there are usually several coupled loads analyses (CLA) performed: preliminary design, critical design, final design and verification loads analysis (VLA). A final design CLA is the last analysis conducted prior to model delivery to the shuttle program for the VLA. The finite element models used in the final design CLA and the VLA are test verified dynamic math models. Mission 6A is the first of many flights of the Multi-Purpose Logistics Module (MPLM). The MPLM was developed by Alenia Spazio S.p.A. (an Italian aerospace company) and houses the International Standard Payload Racks (ISPR) for transportation to the space station in the shuttle. Marshall Space Flight Center (MSFC), the payload integrator of the MPLM for Mission 6A, performed the final design CLA using the M6.OZC shuttle data for liftoff and landing conditions using the proper shuttle cargo manifest. Alenia performed the preliminary and critical design CLAs for the development of the MPLM. However, these CLAs did not use the current Mission 6A cargo manifest. An evaluation of the preliminary and critical design performed by Alenia and the final design performed by MSFC is presented.

Bookout, Paul S.↗