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The joint space mission is briefly summarized. Spacecraft rendevous, docking, and recovery are discussed. Biographies of the joint crew members are included.
The author has identified the following significant results. A pilot study was conducted to determine the feasibility of mapping land use in the Great Lakes Basin area utilizing ERTS-1 data. Small streams were clearly defined by the presence of trees along their length in predominantly agricultural country. Field patterns were easily differentiated from forested areas; dairy and beef farms were differentiated from other farmlands, but no attempt was made to identify crops. Large railroad lines and major highway systems were identified. The city of Erie and several smaller towns were identified, as well as residential areas between these towns, and docks along the shoreline in Erie. Marshes, forests, and beaches within Presque Isle State Park were correctly identified, using the DCLUS program. Bay water was differentiated from lake water, with a small amount of misclassification.
A computer simulation of the ionospheric experiment of the Apollo-Soyuz Test Project (ASTP) was performed. ASTP is the first example of USA/USSR cooperation in space and is scheduled for summer 1975. The experiment consists of performing dual-frequency Doppler measurements (at 162 and 324 MHz) between the Apollo Command Service Module (CSM) and the ASTP Docking Module (DM), both orbiting at 221-km height and at a relative distance of 300 km. The computer simulation showed that, with the Doppler measurement resolution of approximately 3 mHz provided by the instrumentation (in 10-sec integration time), ionospheric-induced Doppler shifts will be measurable accurately at all times, with some rare exceptions occurring when the radio path crosses regions of minimum ionospheric density. The computer simulation evaluated the ability of the experiment to measure changes of columnar electron content between CSM and DM (from which horizontal gradients of electron density at 221-km height can be obtained) and to measure variations in DM-to-ground columnar content (from which an averaged columnar content and the electron density at the DM can be deduced, under some simplifying assumptions).
The preparation of the analytical approach and of the related software used in the inversion of the differential and rotating Doppler data obtained from the ionospheric experiment of the Apollo-Soyuz Test Project (ASTP) is discussed. These data were collected in space-to-space paths (between the ASTP Docking Module (DM) and the Apollo Command Service Module and in space-to-ground paths (between the DM and ground). The Doppler links operated at 162 and 324 MHz and have an accuracy better than 3 MHz over 10-sec integration time. The inversion approach was tested with dummy data obtained with a computer simulation. It was found that a measurement accuracy of 1 to 10% in the value of the horizontal electron density gradient at 221-km altitude can be achieved, in space-to-space paths. For space-to-ground paths near the orbital plane, possible effects of the horizontal gradients on the received differential Doppler shifts were identified. It was possible to reduce the gradient-associated errors in the inversion that leads to the columnar electron content by approximately one-half. Accuracies of 5 to 10% in columnar electron content are achievable, with this gradient-compensation technique.
Description of the optical and structural design requirements, mechanical and thermal response analyses, final design features, and testing procedures employed in the development of a large window mounted on the earth-facing side of the multiple docking adapter (MDA) of the Skylab manned space vehicle. This window was designed for the S190 earth resources multispectral camera and was protected from the space environment during nonuse periods by a hinged cover operated from within the MDA. The camera required a viewing area approximately 43 by 58 cm. A single glass pane 4.1 cm thick was selected to minimize optical distortions. Heaters on the glass and frame were designed to control distortions caused by thermal gradients in the glass.
The Shuttle/Orbiter Program requirements relative to operational and performance parameters of the CCTV (closed circuit television) subsystem and their influence upon design considerations are presented. The anticipated use of the CCTV for rendezvous, docking, manipulator arm operation, satellite inspection and general orbiter operations is outlined to establish the performance requirements of each subsystem element. Typical physical characteristics, interface parameters, and remote-control design philosophy are briefly described.
Range and range rate are crucial parameters which must be available to the operator during remote controlled orbital docking operations. A method was developed for the estimation of both these parameters using an aided television system. An experiment was performed to determine the human operator's capability to measure displayed image size using a fixed reticle or movable cursor as the television aid. The movable cursor was found to yield mean image size estimation errors on the order of 2.3 per cent of the correct value. This error rate was significantly lower than that for the fixed reticle. Performance using the movable cursor was found to be less sensitive to signal-to-noise ratio variation than was that for the fixed reticle. The mean image size estimation errors for the movable cursor correspond to an error of approximately 2.25 per cent in range suggesting that the system has some merit. Determining the accuracy of range rate estimation using a rate controlled cursor will require further experimentation.
Extravehicular activity (EVA) is a baselined Shuttle Orbiter capability. It can provide cost-effective servicing operations for payloads, on-orbit repair, and techniques for meeting various on-orbit contingencies. The basic EVA system planned consists of Orbiter-integral provisions, carry-on life support provisions, and EVA support equipment provisions. The Orbiter-integral provisions include the internal airlock, the EVA Egress module, and the docking module, each of which provides an egress path. The carry-on life support provisions will be two Extravehicular Mobility Units (EMU), composed of an Astronaut Life Support Assembly (ALSA) and a Space Suit Assembly (SSA). The support equipment includes tethers, special tools, translation aids, and workstations. The Shuttle Orbiter EVA requirements and possible tasks, EVA crew rescue equipment and techniques, crew support, EVA training, and EVA timeline activities are described.
A brief overview is presented of the Apollo-Soyuz Test Project. The mission objectives are summarized, and the mission profile is described. Other topics discussed include the reasons why the U.S. built the docking module, Soviet expenditures, use of the ATS-6 relay satellite to improve communications and television coverage, crew training, and safety aspects of the Soyuz spacecraft. It is noted that technology transfer has been minimal and that joint U.S.-Soviet space exploration may be a result of the project.
The preflight mission plan of the Apollo-Soyuz project is summarized, and the scientific experiments planned for the flight are described. Emphasis is on coupling procedures and docking modules. Experiments discussed comprise astronomical studies, geophysical studies, bioscientific studies, and application-oriented studies. The unique gravity-free space environment will provide favorable conditions for uniform materials construction. In addition, biological electrophoresis investigations in a perturbation-free medium will have substantial scientific contributions to make.
A manned spacecraft thermal scale modeling program is described. The program consisted of the design, construction, instrumentation, testing, data correlation, and associated analysis of a transient thermal scale model (TSM) of the Subsystem Test Bed (STB). The STB was chosen as a representative manned spacecraft for which detailed thermal vacuum test data were available. The STB is a cylindrical vehicle (15 ft diameter by 8.3 ft high) with four docking hatches and six windows. The pressure shell is insulated with multilayer insulation and protected by meteoroid shields. Four truss assemblies were used to support the STB during testing. It was concluded that thermal scale modeling can be used as an effective thermal design/verification tool for manned spacecraft. Thermal analysis can be used in conjunction with scale model testing to provide a verified math model that can be applied to the prototype manned spacecraft.
The application of analytical concepts developed to facilitate the design and analysis of the thermal simulator for the Apollo Soyuz docking module is discussed. The functions used to mathematically formulate the irradiance from a quartzline lamp and reflector are described with examples of applications to other geometries. General information is denoted for utilization of the functions in computer programs with approximate computer storage and statement requirements.
Mission planning, systems analysis, and design concepts for the Space Shuttle/Spacelab system for extended manned operations are described. Topics discussed are: (1) payloads, (2) spacecraft docking, (3) structural design criteria, (4) life support systems, (5) power supplies, and (6) the role of man in long duration orbital operations. Also discussed are the assembling of large structures in space. Engineering drawings are included.
Bodies/systems need to be stopped and locked/latched at the end of their path. Some examples of these systems in the aerospace industry (including launch vehicle, spacecraft, and the ground support equipment) are the command module access arm, service arms, docking module of the ASTP and the orbiter access arm for the space shuttle. Two major aspects are covered: (1) various methods of latching and (2) selection of the optimum method for latching, depending on the application and the design requirement criteria.
The baseline definition of the Space Tug discussed herein is the one necessary to meet current payload mission model requirements in the mid-1980's for the least risk and development investment. This baseline Space Tug is a nominal 15-ft diameter, 30-ft long, LOX/LH2 stage with a main propellant capacity of about 50,000 lbs. Once deployed from the Space Shuttle in orbit, it is designed to automatically deliver spacecraft to a predetermined position and velocity and/or rendezvous and dock with prepositioned spacecraft for servicing or retrieval. The Tug would normally be returned to the vicinity of the Shuttle Orbiter, with or without spacecraft, to be retrieved and returned to earth in the Shuttle. Design characteristics, performance requirements, projected activities, and subsystems features are described.
The dual differential radiometer (DDR) was tested to determine its capability for measuring suspended sediment and chlorophyll in turbid waters. Measurements were obtained from a boat dock and from a helicopter with combinations of sample and reference filters with peak transmissions at various wavelengths. Water samples were taken concurrently and were analyzed for light scattering, particle count, and total chlorophyll. Least-squares estimates of the linear relationship between DDR output and the water parameters yielded correlation coefficients of less than 0.7. Under the turbid water conditions of the present tests, the DDR did not accurately measure either suspended sediment or chlorophyll. A precise knowledge of the spectral signatures of various pollutants might enable appropriate filters to be selected for tuning the DDR to monitor a particular pollutant.
A ladar (laser radar) sensor designed around a pulsed passively Q-switched CO2 laser, capable of a efficient and rapid scans with a narrow beam over a wide field of view, is considered for surveillance and tracking applications in space. The output is a train of narrow pulses with a controllable pulse repetition rate. A resonant vibrating mirror in back of a classical Gregorian telescope, and a plane pointing mirror in front for beam steering, are used in scanning. Scan pulse sequences are described and illustrated. The 10.6 micron ladar set is under consideration as baseline sensor for various space rendezvous and docking applications.
Algorithms and equations are used for conversion of standard television imaging system information into directly usable spatial and dimensional information. System allows utilization of spacecraft imagery system as sensor in application to operations such as deriving spacecraft steering signal, tracking, autonomous rendezvous and docking and ranging.