Ground Support Systems Research Articles

The BeppoSAX mission facilities

The BeppoSAX Ground Support System main functions are: • - Observation Proposal reception and archiving • - Mission Planning and observation feasibility checks • - Long and Short term Observation Scheduling up to the detailed weekly planning and Telecommands sequenced generation and uplinking • - Telemetry acquisition, spacecraft and payload monitoring and control • - Attitude and orbit reconstruction • - Orbit by orbit scientific and housekeeping raw Telemetry acquisition and archiving • - Quick-Look and Off-line Data Analysis • - Mission data reformatting and distribution as Final Observation Tapes to the Observation Proposal PI. All the above functionalities are integrated to obtain an end-to-end operation approach to the scientific mission.

BeppoSAX Attitude Operations for GRB Follow Up

This poster describes the attitude dynamics software, Attitude and Orbit Control Ground Support System (AOCGSS), which was developed by TELESPAZIO and integrated in the Operations Control Centre (OCC), in order to support the on ground operations of the Attitude & Orbit Control Subsystem (AOCS). In particular its involvement during the operations performed to carry out the Gamma Ray Burst (GRB) Follow Up is described.

Faster, better, cheaper space exploration

For cost and quality reasons, NASA is allowing its contractors great leeway in designing and building new systems. Here, the author describes how this hands-off approach worked when Hewlett-Packard built the electrical ground support system for the Lunar Prospector, which will mark Earth's return to the Moon after 25 years.

TEMPORARY SUPPORT TO BASEMENT EXCAVATIONS AND STRUT LOAD MONITORING.

The temporary ground support systems used for the construction of three separate basements are described briefly. The basements varied in depth between 6 and 16 m and had between one and three levels of struts. The loads in the struts were monitored during excavation and construction of the permanent works. Temperatures were also monitored. The results of this monitoring are presented and compared with the design loads. The difficulties encountered are described and conclusions drawn.

Field observations and analytical modeling of fracture network permeability in hydrocarbon reservoirs

Determining the magnitude and orientation of in situ stresses is one of the most critical factors in designing underground excavations and choosing ground support systems. Generally as mining progresses deeper, in situ stress plays a significant role in design considerations. In an effort to further characterize the rock mass in the deep levels of the Homestake Mine, researchers from the Spokane Research Center have completed overcore, i.e. stress relief, measurements using the Bureau of Mines-developed borehole deformation gage. The Homestake Mine geology is comprised of three main geologic formations (Homestake, Ellison, and Poorman) each with distinct material properties. The drill site was chosen in an attempt to collect all the stress relief data in the ore-bearing Homestake formation alone. However, as drilling progressed, overcore measurements were taken in two different rock types and across a geologic contact. This paper examines the effects of variable geology on stress determinations and compares these recent stress measurements and field observations with other in situ measurements collected in previous research investigations at the mine.

Characterization of in situ stress conditions at depth-homestake mine, lead, South Dakota

Abstract Determining the magnitude and orientation of in situ stresses is one of the most critical factors in designing underground excavations and choosing ground support systems. Generally as mining progresses deeper, in situ stress plays a significant role in design considerations. In an effort to further characterize the rock mass in the deep levels of the Homestake Mine, researchers from the Spokane Research Center have completed overcore, i.e. stress relief, measurements using the Bureau of Mines-developed borehole deformation gage. The Homestake Mine geology is comprised of three main geologic formations (Homestake, Ellison, and Poorman) each with distinct material properties. The drill site was chosen in an attempt to collect all the stress relief data in the ore-bearing Homestake formation alone. However, as drilling progressed, overcore measurements were taken in two different rock types and across a geologic contact. This paper examines the effects of variable geology on stress determinations and compares these recent stress measurements and field observations with other in situ measurements collected in previous research investigations at the mine.

IMACCS: A DEMONSTRATION IN REENGINEERING GROUND DATA SYSTEMS DEVELOPMENT

AbstractThis paper describes a successfully functioning, commercial, off‐the‐shelf (COTS)‐based ground support system called the Integrated Monitoring, Analysis, and Control COTS System (IMACCS). IMACCS was implemented as a prototype by Goddard Space Flight Center (GSFC), Mission Operations and Data Systems Directorate (MO&DSD) to operate NASA's Solar Anomalous and Magnetospheric Particle Explorer (SAMPEX). IMACCS was conceived specifically to build on previous experience in testbed evaluation of COTS products. The purpose of the IMACCS project was to integrate a typical set of such tools, connect them to live tracking and telemetry data from a real, on‐orbit satellite, and perform shadow mission operations. The objective of the IMACCS project was to assess the completeness, robustness, and performance of a COTS‐based ground system. As a constraint, IMACCS was to be implemented within 90 days of project approval. This paper discusses the challenges that led to the IMACCS project; the processes used for implementing IMACCS; how these processes fit within MO&DSD's reengineered ground systems development processes; and the results obtained by comparing IMACCS' requirements, operations, costs, and implementation process against the currently operating ground system.

Innovative liner support trials in underground hardrock mines: S. Espley, C. Langille & D. McCreath, CIM Bulletin, 88(922), 1995, pp 66–74

In 1993, trials of two innovative applications of liner support involving the replacement of bolts in the ground support system were undertaken at Inco mines. The first trial involved an evaluation of the effect of dynamic loading on mesh-reinforced boltless shotcrete in a sub-level cave mining area on 2400 level at Stobie Mine. The second trial involved an evaluation of the MIROC Mineguard spray-on liner as a replacement for bolts and screen support, or as a replacement for screen support alone, in a topsoil heading of a bulk, VRM (vertical retreat mining) stope on 3240 level at Lower Coleman Mine. In the Stobie Mine trial, an uppers retreat heading was supported using a two-pass system. Fist, shotcrete was applied 2 inches thick, following by pinning of mesh screen to the back and walls. A second pass of another 2 inches of shotcrete was then performed. For recovery of the ore zone, a vertical slot was created using a Borepak blind boring machine. The uppers rings were blasted, one or two rings at a time, starting at the slot and retreating out of the heading. During blasting of the production rings, blast monitoring was used to record the ppvs (peak particle velocities). For a serie of 5-ring blasts, the maximum ppvs were measured to be 0.4 m/s (16 in./s) with a maximum charge weight per dely of 357 kg (800 lb). Six 5-point convergence measurement stations were set up and after each blast the total rockmass convergence was measured using a tape extensometer. Although a maximum displacement of 100 (4 in.) was measured, the shotcrete still managed to provide some support function. A support damage assessment was also done to try and relate blast vibration of effectiveness of the mesh reinforced shotcrete liner. This trial demonstrated the effect that blasting has, on a support system, and it also demonstrated the necessity of having the mesh reinforcement properly placed within the shotcrete. The Lower Coleman Mine trial involved the development of an engineered design to create a dead-weight loading system to test the standard rockbolts and screen support system versus a polyurethane liner support system, with and without the installation of rock bolts. Each support was evaluated on its ability to support a dead-weight load or a slab of rock having dimensions 12 ft by 20 ft by 4 ft thick. A development and blasting scenario was designed and implemented for the creation of the dead-weight load in the topsill heading. Initially the heading was driven developed 20 ft high and 20 ft wide and then it was advanced another 100 ft using a reduced back height of 15 ft. This created a 5 ft hanging breast, support system. For each test, the brow was drilled off with closely spaced horizontl perimeter holes, each being 12 ft in length and with a 4 ft burden. Additional horizontal perimeter holes were drilled along the shoulders of the brow area to within 1 ft of the back. Further down the drift from the brow, closely spaced up-holes were drilled, each 5 ft in length, to intersect the toe-locations of the horizontal perimeter holes.

On-board artificial neural network multi-star identification system for 3-axis attitude determination

Described is the design of a system allowing three axis attitude determination with no a priori attitude knowledge using a single multi-star tracker. The system allows very accurate, quick, and robust multi-star identification — ideal for spacecraft implementation. The system is designed using commercially available star tracker output and artificial neural network technology. The system identifies the unknown star field in the star tracker's field-of-view, using a rotationally and spatially invariant feature vector and produces the identity of two or more guide stars — allowing 3-axis attitude determination.Application of this system on-board a spacecraft will reduce cost, weight, and development time of the attitude determination system, while maintaining a high degree of simplicity and robustness. This system will enable the reduction or elimination of other attitude determination equipment for a simpler, lighter, and lower power spacecraft for a wide variety of mission scenarios. The system is ideal for autonomous spacecraft operations, reducing ground support systems and cost.

Deep-Space Navigation—An Overview

This paper presents a bird's eye view of deep space radio/optical navigation within the solar system. The regulated functioning of the spacecraft and the ground support systems are reviewed. Broadly, it outlines the inertial navigation of the launch vehicle, trajectory determination of the spacecraft through Doppler tracking, link budget, telemetry capabilities, frequencies and data rates, technology trends and limitations, and illustrative mentions about a few Odysseys.

Reliability and Quality Assurance of Space Systems

Reliability and Quality Assurance disciplines serve to implement all considerations that are imperative to ensure harmony of design and workmanship of space systems in spare. This article discusses certain important aspects, and includes due references to the considerations that render the ground support systems dependable for all mission operations.

Preliminary methodology for design of stable drifts for the Yucca Mountain project : Bauer, S J; Ehgartner, B L; Hardy, M P Proc 1st Annual Topical Meeting on High Level Radioactive Waste Management, Las Vegas, 8–12 April 1990V1, P59–64 Publ ANS/ASCE: La Grange Park, 1990

This paper defines a methodology and criteria by which the stability of underground repository drifts in tuff is determined and from which the ground support system is designed. Preconstruction evaluations of stability are required for planning and to support the license application process. The emphasis is on analytical numerical methods because, at this time, empirical data are generally not available for excavations in welded tuff at elevated temperatures or in seismic environments. Observational methods are only applicable during construction. The methodology suggests analytical techniques for the range of structural conditions of the rock currently expected at the Yucca Mountain site: systematically jointed rock masses, randomly jointed rock masses, and widely spaced discrete joints. The analyses must also load on the rock in the vicinity of excavations that result from in situ stresses, thermal expansion, and seismic events. Large-scale field experiments at the Exploratory Shaft Facility (ESF), and laboratory experiments on ESF samples define the controlling deformation mechanisms and allows evaluation of in situ properties, the methodology presented is expected to evolve. 2 refs., 2 figs.

Automated ground support systems in deep metals mines - shotcrete : Hoskins, J R Proc 7th Annual Workshop Generic Mineral Technology Center Mine Systems Design and Ground Control, Blacksburg, 22–24 October 1989P161–165. Publ Blacksburg: Virginia Polytechnic Institute and State University, 1989

Automated ground support systems in deep metals mines - shotcrete : Hoskins, J R Proc 7th Annual Workshop Generic Mineral Technology Center Mine Systems Design and Ground Control, Blacksburg, 22–24 October 1989P161–165. Publ Blacksburg: Virginia Polytechnic Institute and State University, 1989

Radioastron mission management during operations

Plans for the scientific utilization of the RADIOASTRON system and for the support of these plans by ground system elements are reviewed. The following five elements of the ground support system can be identified: 1) RADIOASTRON Science Centre, a) Satellite Control Centre, 3) Ground Station Network, 4) Ground-based Radio Telescopes, and 5) VLBI Data Processing Centres. General concepts for the interaction of these elements and the requirements for their systems are presented. It is stressed that international collaboration is a very critical item for RADIOASTRON. In particular, collaboration on tracking and orbit determination, phase transfer and wideband down link, coobserving with VLBI network telescopes like VLBA, EVN, and AT is very desirable, notwithstanding the fact that USSR has its own Eurasian network (both for tracking/link and for observing) within its territory.

Methods to reduce floor heave and sides closure along the arched gate roads

Back analysis of experimental results from the laboratory and longwall gate roads have been utilized to elaborate on the causes of floor heave and sides closure along the roadways. Techniques to control and reduce the floor heave and sides closure along mine gate roads with soft floor is discussed. Appropriate, practical and theoretical suggestion is given. Application of some of the techniques, especially those utilizing resin or grout injection into the boreholes, are in the mechanized, high productive and continuous mining necessitating continuous ground reinforcement or support system.

Automated ground support systems in deep metal mines : Dupree, P D Proc 6th Annual Workshop Generic Mineral Technology Center Mine Systems Design and Ground Control, Fairbanks, 31 July–2 August 1988P147–153. Publ Blacksburg: Virginia Polytechnic Institute and State University, 1988

Automated ground support systems in deep metal mines : Dupree, P D Proc 6th Annual Workshop Generic Mineral Technology Center Mine Systems Design and Ground Control, Fairbanks, 31 July–2 August 1988P147–153. Publ Blacksburg: Virginia Polytechnic Institute and State University, 1988

An approach to rescheduling activities based on determination of priority and disruptivity

A constraint-based scheduling system called SPIKE is being used to create long-term schedules for the Hubble Space Telescope. Feedback from the spacecraft or from other ground support systems may invalidate some scheduling decisions and those activities concerned must be reconsidered. A function rescheduling priority is defined, which for a given activity performs a heuristic analysis and produces a relative numerical value that is used to rank all such entries in the order that they should be rescheduled. A function disruptivity is also defined that is used to place a relative numeric value on how much a preexisting schedule would be changed to reschedule an activity. Using these functions, two algorithms (a stochastic neural network approach and an exhaustive search approach) are proposed to find the best place to reschedule an activity. Prototypes have been implemented and preliminary testing reveals that the exhaustive technique produces only marginally better results at much greater computational cost.

Development and current experiences with double-shield TBMs in Italy

Abstract In the field of mechanical tunnel excavation with full-face machines, the most significant step forward is represented by the introduction of the double telescopic shield feature, which allows hard-rock machines to advance successfully in a very wide range of geological conditions with the installation of appropriate ground support systems. Since the prototype machine was designed and first applied in southern Italy in 1973–1977, several major improvements have been introduced by the author to subsequent units, with particular regard to the telescoping section connecting the main shield; the machine direction control and steering systems; and the cutterhead design, also in connection with the continuing development of full-face tunnel boring techniques and equipment.

Spacecraft Attitude Real-time Determination System Based on Multiprocessor Distributed Architecture

Abstract A microprocessorization Spacecraft Attitude Real-time Determination System (SARDS) based on multiprocessor distributed architecture has been implemented. A real-time system architecture suitable for multiprocessor concurrent processing were created. A series of mathematical models implemented on microprocessors, including telemetry signal on-line processing, real-time UDU factorization Kalman filter and system I/O controller were built. The microprocessor hardwares and softwares that matched well with real-time attitude determination tasks and models were designed specially. A series of flight tests were conducted in 1, Feb.,1986. The experiences of SARDS system design and flight tests demonstrated that the realization of all microprocessorization satellite ground support system will be possible.

Mariner Mark II and the Exploration of the Solar System

Mariner Mark II is a concept for the next generatioon of deep-space missions. The project would provide limited, focused sets of Voyager- and Galileo-quality planetary observations at a fraction of the cost of the Voyager and Galileo projects. This article discusses Mariner Mark II's cost goals, scientific objectives, and mission requirements. Strategies for limiting costs include the use of a reconfigurable spacecraft, a multimission ground-support system, and selected new technologies.