Search NASA⌕ Search

SEARCH · Search NASA

Results for “Pallet”

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 181 records · Page 10

A deployable structure and solar array controls experiment for STEP

A candidate configuration for a controls experiment on the Space Technology Experiments Platform (STEP) is described. The elements of the experiment are the mast, the solar array, and an articulation module between the two. The characteristic dimensions are very compatible for integration on a pallet such a STEP's proposed configuration. The controls' objective would be the measurement of orbiter interaction as well as the system identification of the appendages. The flight experiment configuration would also provide a test bed for various active vibration controls concepts. The instrumentation being considered would measure accelerations, strains, displacements, and temperatures. The deployable mast has eight elements defining a structural bay. Uniaxial measurements would be required to define loads at a cross section of the structure. Displacements due to thermal distortion of the mast and the local state of the solar concentrator may be measured by an optical ranging technique from the orbiter aft flight deck.

Nishimoto, T. S.↗

The development of a high-capacity instrument module heat transport system, appendixes

Data sheets provide temperature requirements for 82 individual instruments that are under development or planned for grouping on a space platform or pallet. The scientific objectives of these instrument packages are related to solar physics, space plasma physics, astronomy, high energy astrophysics, resources observations, environmental observations, materials processing, and life sciences. System specifications are given for a high capacity instrument module heat transport system to be used with future payloads.

Source record↗

Launch processing for Spacelab 1

The final integration of Spacelab payloads with the Shuttle is described. Attention is given to launch processing planning, schedules, quality control, and problem reports and configuration maintenance. Also covered are the integration and checkout of individual and combined experiments, mounting the end cones, attachment of the transfer tunnel, and inclusion of an extra experiments pallet. The entire Spacelab module was subjected to a full systems simulation before deliverance to the Orbiter bay. Modular parts that were transferred from building-to-building were placed in sealed containers filled with a purged atmosphere during transport.

Mcbrayer, R. O.↗

Modulated beam injection from the Space Shuttle during magnetic conjunctions of STS 3 with the DE 1 satellite

An electron beam emitted from the Office of Space Sciences 1 pallet on STS 3 was pulsed with specially designed very low frequency (VLF) formats in an attempt to generate whistler mode waves. Modulated operations of the beam emitted by a fast pulse electron generator (FPEG) were initiated during times of magnetic conjunctions between STS 3 and the high-altitude DE 1 satellite equipped with broadband VLF receivers. Coordinated FPEG/VLF modulation and DE 1 wideband data acquisition were achieved in 12 different cases. No evidence of any waves generated by FPEG were detected on the DE 1 analog wideband data. However, it is shown that in all of the cases, either the STS 3 attitude was such that the emitted electrons struck the main body of the vehicle, or it was not possible for whistler mode waves to propagate from the STS 3 location up to the vicinity of the DE 1 satellite.

Inan, U. S.↗

Radiation measurements aboard Spacelab 1

The radiation environment inside Spacelab 1 was measured by a set of passive radiation detectors distributed throughout the volume inside the module, in the access tunnel, and outside on the pallet. Measurements of the low linear energy transfer (LET) component obtained from the thermoluminescence detectors ranged from 102 to 190 millirads, yielding an average low LET dose rate of 11.2 millirads/day inside the module, about twice the low LET dose rate measured on previous flights of the Space Shuttle. Because of the higher inclination of the orbit (57 versus 28.5 deg for previous Shuttle flights), substantial fluxes of highly ionizing high charge and energy galactic cosmic ray particles were observed, yielding an overall average mission dose-equivalent of about 150 millirems, more than three times higher than that measured on previous Shuttle missions.

Benton, E. V.↗

Measurements of electromagnetic interference on OV102 Columbia using the plasma diagnostics package

The third Space Shuttle mission's OSS-1 payload included 30 Hz-800 MHz and S-band receivers which assessed the intentional (transmitter) and unintentional (subsystem) EMI levels. It was noted that, at the pallet location, the UHF voice downlink transmitter field strengths did not exceed 0.1 V/m. At the remote manipulator system, the figure was 0.5 V/m. Below 300 kHz, the magnetic field noise was 30 dB pT + or - 20 dB, while the electric field noise was broadband and variable over at least 60 dB, depending on thruster firings and Orbiter attitude. This noise may have been generated by the Orbiter's interaction with the ambient plasma.

Shawhan, S. D.↗

The evolution of small payload carrier systems

The design of a bridge-like structure to span the Space Shuttle cargo bay but occupy only 3 feet of its length is discussed. The new structure was named the Missions Peculiar Equipment Support Structure (MPESS). The basic design requirements were as follows: to serve as support structure for small number of experiments; to occupy the minimal length of cargo bay; to have a standard interface hole pattern; to provide support at an elevated position; to employ standard Spacelab pallet trunnion; and to ensure natural frequency between the STS liftoff and landing frequency. The bridge-like structure is a riveted and bolted truss with machind end fittings which interface with the Spacelab trunnions. The structure is fabricated from aluminum alloy and assembled with stainless steel fasteners.

Breaux, C. G.↗

The design, fabrication and delivery of a spacelab neutral buoyancy Instrument Pointing System (IPS) mockup

Underwater simulations of EVA contingency operations such as manual jettison, payload disconnect, and payload clamp actuation were used to define crew aid needs and mockup pecularities and characteristics to verify the validity of simulation using the trainer. A set of mockup instrument pointing system tests was conducted and minor modifications and refinements were made. Flight configuration struts were tested and verified to be operable by the flight crew. Tasks involved in developing the following end items are described: IPS gimbal system, payload, and payload clamp assembly; the igloos (volumetric); spacelab pallets, experiments, and hardware; experiment, and hardware; experiment 7; and EVA hand tools, support hardware (handrails and foot restraints). The test plan preparation and test support are also covered.

Vanvalkenburgh, C. N.↗

Vibroacoustic study of the NASA Goddard Space Flight Center OSS-1 payload

A comparative evaluation of shuttle liftoff and ground test random response data obtained from the Office of Space Science-1 (OSS-1) pallet payload flown in the cargo bay of STS-3 is presented. The study was initiated to evaluate the possibility that the payload flight vibration response can exceed that occurred during ground test when the ground test acoustic excitation is normalized to the flight acoustic environment. In addition, the analytically derived response from the Vibroacoustic Payload Environment Prediction System (VAPEPS) is compared with OSS-1 ground test results.

Lee, Y. A.↗

Shuttle tethered satellite program

Features and applications of the Shuttle tethered satellite system (TSS) are outlined. The TSS would be mounted on a normal cargo pallet and used to deploy or retrieve payloads weighing up to 500 kg from the Orbiter by reeling in or unreeling a tether line extended along the gravity gradient vertical. Attaching a conducting wire to the tether would permit electrodynamic measurements of space plasma. An initial mission under development is to deploy an instruments package 20 km above the Orbiter with a conducting wire tether, thereby obtaining data on low frequency hydromagnetic waves generated by tether passage through the space plasma. An aerodynamics package could also be lowered to 130 km, where measurements can be made with magnetometers for geoscience data, atmospheric composition, and cosmic dust can be collected. Details of engineering assignments for the TSS divided up between NASA and the Italian National Research Council are discussed.

Nolan, M. B.↗

A practical scheduling algorithm for Shuttle-based astronomy missions

In the Astro mission series (initial flight planned for March, 1986), the Shuttle will be used as a dedicated stellar astronomy observatory. A modified Spacelab pallet is to be used for the Astro payload, which will consist of three ultraviolet (UV) telescopes and a wide field camera mounted together on a single gimbal mount called the Inertial Pointing System (IPS). Three flights of 7-10 days duration are to be made with the same payload at intervals of 8-9 months. Previous experience has shown that changes in design requirements are inevitable, and the evolution of operational concepts will effect changes in scheduling algorithm software. For these reasons, the design goals of the Astron algorithm and its family of auxiliary software modules have been related to functional modularity, constraint flexibility, user friendliness, and 'light' input requirements. Attention is given to hardware characteristics, environmental constraints, the basic criteria function, 'Cinderella' logic, counters and constraints, and scheduling trends.

Guffin, O. T.↗

Orbit-on-demand vehicles - Mission possible, but one-day turnaround?

The next generation launch-on-demand manned orbital vehicles will ideally be able to perform plane change maneuvers for rendezvous. Plane-changes of, e.g., 11 deg, will require a 3000 fps on-orbit maneuver velocity. Any plane-change capabilities beyond 800 fps rapidly increase the necessary vehicle weight. Sensitivity studies of the payload weight/vehicle weight, the presence or absence of air-breathing engines, high acceleration, etc., indicated that advances are required in the payload stowage pallet, thermal protection system, fault detection electronics, line-replaceable units, and accessibility to realize one-day turnaround. The spacecraft would also need autonomous systems checks and launch from minimum support sites reached by air ferry. A horizontal take-off, two-stage subsonic launch vehicle so far offers the lowest weight, maximum flexibility and minimum support combination of all configurations under consideration.

Talay, T. A.↗

Spacelab - The multimission machine

The high point of a decade of collaboration between NASA and ESA may have been the Space Shuttle/Spacelab-1 mission of 1983, which was dedicated to multidisciplinary science and verification tasks. Still to be verified by Spacelab-2, on the basis of elements designed, developed and funded by ESA, are 'igloo' pallets for dedicated missions and the Instrument Pointing System. Further variations of mixed cargo carrier systems are the Materials Science Laboratory, the Structural Technology Experiments Platform, and the Dedicated Discipline Laboratories, whose various features and capabilities are presently discussed.

Lohman, R. L.↗

Data requirements for verification of ram glow chemistry

A set of questions is posed regarding the surface chemistry producing the ram glow on the space shuttle. The questions surround verification of the chemical cycle involved in the physical processes leading to the glow. The questions, and a matrix of measurements required for most answers, are presented. The measurements include knowledge of the flux composition to and from a ram surface as well as spectroscopic signatures from the U to visible to IR. A pallet set of experiments proposed to accomplish the measurements is discussed. An interim experiment involving an available infrared instrument to be operated from the shuttle Orbiter cabin is also be discussed.

Swenson, G. R.↗

Radiation mapping on Spacelab 1: Experiment no. INS006

The first attempt at mapping the radiation environment inside Spacelab is described. Measurements were made by a set of passive radiation detectors distributed throughout the volume inside the Spacelab 1 module, in the access tunnel and outside on the pallet. Measurements of the low linear energy transfer (LET) component obtained from the TLD thermoluminescent detectors (TLD) ranged from 92 to 134 mrad, yielding an average low LET dose rate of 10.0 mrads/day inside the module. Because of the higher inclination orbit, substantial fluxes of highly ionizing (HZE particles) high charge and energy galactic cosmic rays were observed for the first time on an STS flight, yielding an overall average mission dose-equivalent of 295 mrem, or 29.5 mrem/day, which is about three times higher than that measured on previous STS missions. Little correlation is found between measured average dose rates or HZE fluences and the estimates shielding throughout the volume of the module.

Benton, E. V.↗

CID-720 aircraft high-environment flight instrumentation system

The high-environment flight instrumentation system was designed to acquire Langley's structural response data during the full scale transport-controlled impact demonstration test. There was only one opportunity for data acquisition. Thus, a high reliability and crashworthy design approach was implemented. The approach featured multi-level redundancy and a vigorous quality assurance testing program. Complying with an accelerated schedule, the instrumentation system was developed, tested and shipped within 18 months to Dryden Flight Research Facility. The flight instrumentation system consists of two autonomous data systems, DAS #1 and #2, and an excellent checkout subsystem. Each data system is partitioned into four pallets. The system was designed to operate on manned and unmanned flights. There are 176 data channels per data system. These channels are sequentially sampled and encoded into 1 megabit/sec pulse code modulation (PCM) data signal. To increase the probability of success, a special PCM distribution subsystem was developed. This subsystem distributes the PCM signal to two transmitters, one delay memory, and eight recorder tracks. The data on four of these trackes was digitally delayed approximately 300 msec to maximize data acquisition during impact. Therefore each data system's data is redundantly recorded onboard and on the ground. There are two time code generators. Parallel time from each is encoded into both data systems. Serial time from each is redundantly recorded on both onboard recorders. Instrumentation power is independent of aircraft power and self-contained.

Calloway, R. S.↗

CID-720 aircraft Langley Research Center preflight hardware tests: Development, flight acceptance and qualification

The testing conducted on LaRC-developed hardware for the controlled impact demonstration transport aircraft is discussed. To properly develop flight qualified crash systems, two environments were considered: the aircraft flight environment with the focus on vibration and temperature effects, and the crash environment with the long pulse shock effects. Also with the large quantity of fuel in the wing tanks the possibility of fire was considered to be a threat to data retrieval and thus fire tests were included in the development test process. The aircraft test successfully demonstrated the performance of the LaRC developed heat shields. Good telemetered data (S-band) was received during the impact and slide-out phase, and even after the aircraft came to rest. The two onboard DAS tape recorders were protected from the intense fire and high quality tape data was recovered. The complete photographic system performed as planned throughout the 40.0 sec of film supply. The four photo power distribution pallets remained in good condition and all ten onboard 16 mm high speed (400 frames/sec) cameras produced good film data.

Pride, J. D.↗

The Imaging Spectrometric Observatory

Design and performance features of the Imaging Spectrometric Observatory (ISO) first flown on Spacelab 1 for atmospheric, earth surface and stellar monitoring are outlined. The ISO has five grating spectrometers fitted with CCD arrays for simultaneously gathering spectral and spatial data. The instrument covered the 300-12,700 A range on the Spacelab 1 flight, when it was mounted on a pallet and used for atmospheric scans at high solar zenith angles. A future mission is planned which will include limb-viewing of OH, NO, ClO and NO2 radicals in the middle atmosphere to complement the data collected in the Upper Atmosphere Research Satellite program. Technical details are presented of the instrument components and ground- and balloon-borne test results.

Torr, D. G.↗