Search NASA⌕ Search

SEARCH · Search NASA

Results for “block diagram”

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 109 records · Page 6

V/STOL tilt rotor study. Volume 5: A mathematical model for real time flight simulation of the Bell model 301 tilt rotor research aircraft

A mathematical model for real-time flight simulation of a tilt rotor research aircraft was developed. The mathematical model was used to support the aircraft design, pilot training, and proof-of-concept aspects of the development program. The structure of the mathematical model is indicated by a block diagram. The mathematical model differs from that for a conventional fixed wing aircraft principally in the added requirement to represent the dynamics and aerodynamics of the rotors, the interaction of the rotor wake with the airframe, and the rotor control and drive systems. The constraints imposed on the mathematical model are defined.

P B Harendra↗

ASTP ranging system mathematical model

A mathematical model is presented of the VHF ranging system to analyze the performance of the Apollo-Soyuz test project (ASTP). The system was adapted for use in the ASTP. The ranging system mathematical model is presented in block diagram form, and a brief description of the overall model is also included. A procedure for implementing the math model is presented along with a discussion of the validation of the math model and the overall summary and conclusions of the study effort. Detailed appendices of the five study tasks are presented: early late gate model development, unlock probability development, system error model development, probability of acquisition and model development, and math model validation testing.

Ellis, M. R.↗

Periodic attitude control of a slowly spinning spacecraft.

A periodic attitude control system is presented which permits control of secular errors of a slowly spinning spacecraft operating in a high disturbance environment. Attitude errors of the spin-axis are detected by sun sensors (or rate gyros) and are controlled by a periodic control law which modulates external control torques generated by mass expulsion torquers. Attitude stability during the uncontrolled periods is obtained passively via the vehicle spin momentum. Equations of motion, a system block diagram, and design parameters are presented for a typical spacecraft application. Simulation results are included which demonstrate the feasibility of the novel control concept. Salient features of the periodic control approach are implementation simplicity, excellent response, and a propellant utilization efficiency greater than 75 percent.

Todosiev, E. P.↗

Apollo 15 and 16 ground-commanded television assembly.

During the Apollo 15 and 16 missions, a special camera provided the scientific community and the home viewer with real-time coverage of the lunar exploration. The lunar blast-off of the Apollo 16 ascent module was tracked by the mission controller at NASA's Manned Space Center and watched 250,000 miles away on earth. The operation of this television camera and the remote control unit are described and block diagrams given. Ground-command capability from the Mission Control Center permitted versatility and optimization of the TV coverage, without diverting the astronauts from their primary role of lunar exploration.

Soltoff, B. M.↗

Telecommunications systems design techniques handbook

Handbook presents design and analysis of tracking, telemetry, and command functions utilized in these systems with particular emphasis on deep-space telecommunications. Antenna requirements are also discussed. Handbook provides number of tables outlining various performance criteria. Block diagrams and performance charts are also presented.

Edelson, R. E.↗

Stratoscope 2 integrating television camera

The development, construction, test and delivery of an integrating television camera for use as the primary data sensor on Flight 9 of Stratoscope 2 is described. The system block diagrams are presented along with the performance data, and definition of the interface of the telescope with the power, telemetry, and communication system.

Source record↗

Shuttle mission simulator baseline definition report, volume 2

The baseline definition report for the space shuttle mission simulator is presented. The subjects discussed are: (1) the general configurations, (2) motion base crew station, (3) instructor operator station complex, (4) display devices, (5) electromagnetic compatibility, (6) external interface equipment, (7) data conversion equipment, (8) fixed base crew station equipment, and (9) computer complex. Block diagrams of the supporting subsystems are provided.

Dahlberg, A. W.↗

The applicability of frame imaging from a spinning spacecraft. Volume 1: Summary report

A detailed study was made of frame-type imaging systems for use on board a spin stabilized spacecraft for outer planets applications. All types of frame imagers capable of performing this mission were considered, regardless of the current state of the art. Detailed sensor models of these systems were developed at the component level and used in the subsequent analyses. An overall assessment was then made of the various systems based upon results of a worst-case performance analysis, foreseeable technology problems, and the relative reliability and radiation tolerance of the systems. Special attention was directed at restraints imposed by image motion and the limited data transmission and storage capability of the spacecraft. Based upon this overall assessment, the most promising systems were selected and then examined in detail for a specified Jupiter orbiter mission. The relative merits of each selected system were then analyzed, and the system design characteristics were demonstrated using preliminary configurations, block diagrams, and tables of estimated weights, volumes and power consumption.

Botticelli, R. A.↗

Synchronous meteorological satellite system description document, volume 4

The command and data acquisition (CDA) station for the Synchronous Meteorological Satellite (SMS) program, located on the Eastern shore of Virginia, is described in terms of facility layout, ground support instrumentation, and capabilities. Data systems and equipment are described in detailed block diagrams. The major subsystems are identified and information on equipment specifications, frequency ranges, and data processing format is given. Automatic picture transmission, data utilization stations, data collection platforms, and the various communication links from the CDA station to the SMS spacecraft are discussed.

Lahzun, J.↗

RI 1170 advanced strapdown gyro

The major components of the RI 1170 gyroscope are described. A detailed functional description of the electronics including block diagrams and photographs of output waveshapes within the loop electronics are presented. An electronic data flow diagram is included. Those gyro subassemblies that were originally planned and subsequently changed or modified for one reason or another are discussed in detail. Variations to the original design included the capacitive pickoffs, torquer flexleads, magnetic suspension, gas bearings, electronic design, and packaging. The selection of components and changes from the original design and components selected are discussed. Device failures experienced throughout the program are reported and design corrections to eliminate the failure modes are noted. Major design deficiencies such as those of the MSE electronics are described in detail. Modifications made to the gas bearing parts and design improvements to the wheel are noted. Changes to the gas bearing prints are included as well as a mathematical analysis of the 1170 gas bearing wheel by computer analysis. The mean free-path effects on gas bearing performance is summarized.

Source record↗

Description of the attitude control, guidance and navigation space replaceable units for automated space servicing of selected NASA missions

Control elements such as sensors, momentum exchange devices, and thrusters are described which can be used to define space replaceable units (SRU), in accordance with attitude control, guidance, and navigation performance requirements selected for NASA space serviceable mission spacecraft. A number of SRU's are developed, and their reliability block diagrams are presented. An SRU assignment is given in order to define a set of feasible space serviceable spacecraft for the missions of interest.

Chobotov, V. A.↗

Apollo Telescope Mount (ATM) gimballed star tracker

Design and development of six gimballed star trackers for Skylab's Apollo Telescope Mount, which performed successfully on all three manned Skylab missions and accumulated a total usage time of approximately 3,500 hours, is described in terms of configurations, materials and construction, qualification testing, performance, and reliability characteristics. A brief program history and design changes incorporated during the life of the program are also discussed. Extensive drawings, block diagrams, and photographs are provided.

Lana, J. D.↗

Analog computation of auto and cross-correlation functions

For analysis of the data obtained from the cross beam systems it was deemed desirable to compute the auto- and cross-correlation functions by both digital and analog methods to provide a cross-check of the analysis methods and an indication as to which of the two methods would be most suitable for routine use in the analysis of such data. It is the purpose of this appendix to provide a concise description of the equipment and procedures used for the electronic analog analysis of the cross beam data. A block diagram showing the signal processing and computation set-up used for most of the analog data analysis is provided. The data obtained at the field test sites were recorded on magnetic tape using wide-band FM recording techniques. The data as recorded were band-pass filtered by electronic signal processing in the data acquisition systems.

Source record↗

Computer model of cardiovascular control system responses to exercise

Approaches of systems analysis and mathematical modeling together with computer simulation techniques are applied to the cardiovascular system in order to simulate dynamic responses of the system to a range of exercise work loads. A block diagram of the circulatory model is presented, taking into account arterial segments, venous segments, arterio-venous circulation branches, and the heart. A cardiovascular control system model is also discussed together with model test results.

Croston, R. C.↗

Polarized crystal-field spectra of micro particles of the moon

The instrumentation used in the investigation is considered, giving attention also to a block diagram of the apparatus used for measuring crystal-field spectra. The basic object of the studies was to identify the states of transition elements in lunar crystals in order to obtain information on the chemistry of their crystallization history. After spectral measurements were obtained, the crystals were analyzed for major and minor elements using the electron microprobe. Mineral spectra are considered, giving attention to pyroxene, olivine, plagioclase, and lunar glasses.

Mao, H. K.↗

A programmable sampling format telemetry system

This paper describes the programmable sampling format telemetry system to be used by the near-earth Small Astronomy Satellite-C (SAS-C) and possible future SAS missions. The concept of the programmable sampling format is introduced and the features of the system are illustrated by an example. The SAS-C telemetry system is described at the block diagram level and redundancy of the system is discussed briefly.

Peterson, M. R.↗

Potential capabilities for compression of information of certain data processing systems

This article undertakes to study a generalized block diagram of a data collection and processing system of a spacecraft in which a number of sensors or outputs of scientific instruments are cyclically interrogated by a commutator, methods of writing the supplementary information in a frame on the example of a certain hypothetical telemetry system, and the influence of statistics of number of active channels in a frame on frame compression factor. The separation of the data compression factor of the collection and processing system of spacecraft into two parts used in this work allows determination of the compression factor of an active frame depending not only on the statistics of activity of channels in the telemetry frame, but also on the method of introduction of the additional address and time information to each frame.

Khodarev, Y. K.↗

Design and performance of a 39cm balloon-borne telescope

A system for stabilizing a balloon-borne telescope using a star sensor device is described. Guide stars from minus four to plus four magnitude can be used and the sensor may be offset with respect to the telescope by as much as plus or minus five degrees in elevation and cross elevation to enable parts of the sky containing no suitable guide stars to be viewed. Acquisition of the guide star and setting of the offset coordinates is carried out by ground command and both may be changed in flight. The main design parameters of the equipment are summarized. Block diagrams and circuit diagrams of the star tracker are provided.

Tomlinson, H. S.↗