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The advent of high speed local area networks has made it possible to interconnect small, powerful computers to function together as a single large computer...This paper examines a model for tracking stations and their requirements for inter-processor communications in the next century.
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Ground controlled teleoperations are expected to be used to augment Space Station manned extravehicular activities (EVA) and Intravehicular activities (IVA). However, ground controlled teleoperations will encounter communications time delays of from 3 to 8 secs. Time delays greater than 1 sec have been shown to be detrimental to safe and efficient teleoperations. Therefore, concepts must be developed to overcome the hazards and limitations of time delays when performing teleoperations using robots. The concept for robot motion primitives incorporate force/torque and tactile sensor feedback to implement the degree of autonomy required for interactive, ground controlled telerobotics. Several primitives are studied that augment human initiated actions by providing rapid response interaction with the physical environment of a telerobot. These primitives are detailed. They constitute a level of intelligent sensing and reaction required to augment human actions through autonomous interaction with the physical environment.
Engineering report on synchronous communications /SYNCOM/ satellite, communications ground stations, telemetry, and control ground systems
Within the Consultative Committee for Space Data Systems (CCSDS), there is an effort to standardize data transfer between ground stations and control centers. CCSDS plans to publish a collection of transfer services that will each address the transfer of a particular type of data (e.g., tracking data). These services will be called Cross Support Transfer Services (CSTSs). All of these services will make use of a common foundation that is called the CSTS Framework. This library implements the User side of the CSTS Framework. "User side" means that the library performs the role that is typically expected of the control center. This library was developed in support of the Goddard Data Standards program. This technology could be applicable for control centers, and possibly for use in control center simulators needed to test ground station capabilities. The main advantages of this implementation are its flexibility and simplicity. It provides the framework capabilities, while allowing the library user to provide a wrapper that adapts the library to any particular environment. The main purpose of this implementation was to support the inter-operability testing required by CCSDS. In addition, it is likely that the implementation will be useful within the Goddard mission community (for use in control centers).
Nexus was a technology demonstrator project that was designed to bridge from the Hubble Space Telescope (HST) to its successor, the Next Generation Space Telescope (NGST). This paper focuses on the process used in designing the ground segment for Nexus and the lessons learned in its development. Ground station cost drivers were: (1) Contact time, (2) Cost of transporting data between the ground stations and control center, and (3) Cost savings via ground automation. We found that reducing the communication requirement in just the first 100 days could have reduced the total ground station cost by 40%. Contact time cost dwarfed the cost trade between automation development and off-shift operations personnel. Real-time Telemetry and Control (T&C) system analysis was divided into: (1) Potential reuse of the Nexus real-time (T&C) system for NGST, (2) Feasibility of using a 'Finite State-Based Modeling' product, and (3) Selecting a Commercial Off the Shelf (COTS) versus Government Off The Shelf (GOTS) products. We found that each of the products evaluated in detail (ASIST, EPOCH 2000, and ITOS) could adequately support basic mission requirements. Lessons learned were: (1) Include operations at the beginning of the mission, and (2) Develop an operations concept as soon as possible.
In flight control, as with any human in the loop system, operator error is an inevitable reality. On the International Space Station (ISS) where crew time and physical resources are precious and often irreplaceable, operator errors can result in significant, irreversible consequences. Flight controllers at the Payload Operations Integration Center (POIC) located at NASA's Marshall Space Flight Center (MSFC) in Huntsville, Alabama know this reality well. At the POIC, operator errors can be caused by a variety of factors, from poor hardware or software design to environmental factors such as time pressure or fatigue. The most difficult errors to address, however, are those which result from ineffective teamwork. To address these teamwork errors, trainers at the POIC have drawn best practices from high reliability industries as well as from our sister ISS control center at the Johnson Space Center (JSC) in Houston, Texas, to develop and implement a new training program focused specifically on teamwork skills. This training program, called Team Skills Training, is inspired by modern and historical training programs developed by NASA and is specifically tailored to the needs of the payload operations flight control team at the POIC. The program consists of training for both certified and trainee flight controllers, and covers team skills topics such as situational awareness, leadership, and communication skills. To maximize effectiveness, the program uses novel instructional techniques which extend beyond the classroom to encourage students to apply what they have learned to their day to day work. Minimizing operator errors in flight control is an endeavor which requires constant vigilance and continuous improvement. At the POIC, Team Skills Training is an important step in this journey.
In flight control, as with any human in the loop system, operator error is an inevitable reality. On the International Space Station (ISS) where crew time and physical resources are precious and often irreplaceable, operator errors can result in significant, irreversible consequences. Flight controllers at the Payload Operations Integration Center (POIC) located at NASA’s Marshall Space Flight Center (MSFC) in Huntsville, Alabama know this reality well. At the POIC, operator errors can be caused by a variety of factors, from poor hardware or software design to environmental factors such as time pressure or fatigue. The most difficult errors to address, however, are those which result from ineffective teamwork.Academic research in teamwork has resulted in the identification of many factors which make cross-functional teaming difficult, including leadership, trust building, and communication challenges. These factors, especially when combined with the challenging environmental factors flight control teams must contend with daily, make the goal of minimizing operator errors in payload operations challenging to achieve. To address such teamwork errors, trainers at the POIC have drawn best practices from high reliability industries such as commercial aviation, healthcare, and nuclear power plants, as well as from our sister ISS control center in Houston, Texas, to develop and institute a new training program focused specifically on teamwork skills.This training program, called the Team Skills Curriculum, is based on the concept of Crew Resource Management (CRM) which was developed by NASA in the 1970s for the commercial aviation industry in response to a series of aviation disasters resulting from ineffective teamwork. CRM was later tailored by the Johnson Space Center (JSC) for use in astronaut and flight control training. The result, called Space Flight Resource Management (SFRM) was formally introduced into manned spaceflight training in the late 90s. SFRM has evolved over the years, but the focus has remained on helping operators develop the skills needed to work as part of an effective team. Using these concepts as well as the latest research in cross-functional teaming and data on specific errors occurring at the POIC, trainers in the integrated flight control training branch created a custom training program for both new and certified payload operations specialists.
The Space Station Training Facility (SSTF) will be the primary facility for training the Space Station Freedom astronauts and the Space Station Control Center ground support personnel. Conceptually, the SSTF will consist of two parts: a Student Environment and an Author Environment. The Student Environment will contain trainers, instructor stations, computers and other equipment necessary for training. The Author Environment will contain the systems that will be used to manage, develop, integrate, test and verify, operate and maintain the equipment and software in the Student Environment.
Network-management software assists in planning, monitoring, and controlling resources of Datalink network. Packet-message network featuring time-division multiple access, frequency and spatial diversity, and dynamic tree-structured routing scheme. Developed for communication between central control station on ground and instrumented aircraft flying over test range. Aircraft derives navigational data from satellites of Global Positioning System, and primary function of Datalink network feeding GPS position data from participating aircraft into control center in real time.
The potential of the Space Station as a versatile scientific laboratory is discussed, reviewing plans under consideration by the NASA Task Force on Scientific Uses of the Space Station. The special advantages offered by the Station for expanding the scope of 'space science' beyond astrophysics, geophysics, and terrestrial remote sensing are stressed. Topics examined include the advantages of a manned presence, the scientific value and cost effectiveness of smaller, more quickly performable experiments, improved communications for ground control of Station experiments, the international nature of the Station, the need for more scientist astronauts for the Station crew, Station on-orbit maintenance and repair services for coorbiting platforms, and the need for Shuttle testing of proposed Station laboratory equipment and procedures.
This paper describes the innovative control of an accelerometer to support the needs of the scientists operating science experiments that are on-board Space Station Freedom (SSF). Accelerometers in support of science experiments on the shuttle have typically been passive, record-only devices that present data only after the mission or that present limited data to the crew or ground operators during the mission. With the advent of science experiment operations on SSF, the principal investigators will need microgravity acceleration data during, as well as after, experiment operations. Because their data requirements may change during the experiment operations, the principal investigators will be allocated some control of accelerometer parameters. This paper summarizes the general-purpose Space Acceleration Measurement System (SAMS) operation that supports experiments on the shuttle and describes the control of the SAMS for Space Station Freedom. Emphasis is placed on the proposed ground-based control of the accelerometer by the principal investigators.
This paper describes the innovative control of an accelerometer to support the needs of the scientists operating science experiments that are on-board Space Station Freedom (SSF). Accelerometers in support of science experiments on the shuttle have typically been passive, record-only devices that present data only after the mission or that present limited data to the crew or ground operators during the mission. With the advent of science experiment operations on SSF, the principal investigators will need microgravity acceleration data during, as well as after, experiment operations. Because their data requirements may change during the experiment operations, the principal investigators will be allocated some control of accelerometer parameters. This paper summarizes the general-purpose Space Acceleration Measurement System (SAMS) operation that supports experiments on the shuttle and describes the control of the SAMS for Space Station Freedom. Emphasis is placed on the proposed ground-based control of the accelerometer by the principal investigators.
Within human factors there is burgeoning interest in the "human-autonomy teaming" (HAT) concept as a way to address the challenges of interacting with complex, increasingly autonomous systems. The HAT concept comes out of an aspiration to interact with increasingly autonomous systems as a team member, rather than simply use automation as a tool. The authors, and others, have proposed core tenets for HAT that include bi-directional communication, automation and system transparency, and advanced coordination between human and automated teammates via predefined, dynamic task sequences known as "plays." It is believed that, with proper implementation, HAT should foster appropriate teamwork, thus increasing trust and reliance on the system, which in turn will reduce workload, increase situation awareness, and improve performance. To this end, HAT has been demonstrated and/or studied in multiple applications including search and rescue operations, healthcare and medicine, autonomous vehicles, photography, and aviation. The current paper presents one such effort to apply HAT. It details the design of a HAT agent, developed by Human Automation Teaming Solutions, Inc., to facilitate teamwork between the automation and the human operator of an advanced ground dispatch station. This dispatch station was developed to support a NASA project investigating a concept called Reduced Crew Operations (RCO); consequently, we have named the agent R-HATS. Part of the RCO concept involves a ground operator providing enhanced support to a large number of aircraft with a single pilot on the flight deck. When assisted by R-HATS, operators can monitor and support or manage a large number of aircraft and use plays to respond in real-time to complicated, workload-intensive events (e.g., an airport closure). A play is a plan that encapsulates goals, tasks, and a task allocation strategy appropriate for a particular situation. In the current implementation, when a play is initiated by a user, R-HATS determines what tasks need to be completed and has the ability to autonomously execute them (e.g., determining diversion options and uplinking new routes to aircraft) when it is safe and appropriate. R-HATS has been designed to both support end users and researchers in RCO and HAT. Additionally, R-HATS and its underlying architecture were developed with generalizability in mind as a modular software applicable outside of RCO/aviation domains. This paper will also discuss future further development and testing of RHATS.
Applications Technology Satellite /ATS/ LAUNCHING, communications, power supply, control, and ground station activities
System performance, system interface compatibility, and system management and operations are analyzed for external and internal communications provided by the modular space station. Mathematical models are utilized to evaluate performances of the various communication links between the MSS and the tracking and data relay satellites, the shuttle, and the ground stations. Communication control design requirements are determined from overall MSS control design and checkout requirements are developed in a related systems study. Parallel design efforts consider equipment configurations for the external communication assembly baseband and the internal communication assembly to accommodate signal transfer and control. The recommended baseline design considers also interfaces between equipment groups and the critical functional and signal characteristics of these interfaces. The data processing assembly has direct communication circuits to the external communication assembly and the control interface is provided via a digital data bus and a remote acquisition and control unit.
Real-time display of data on performance supports decisions regarding maneuvers. Data from sensors aboard airplane transmitted to control station on ground for immediate processing and display. Data-acquisition subsystem aboard airplane uses both pulse code modulation and frequency modulation for transmission of sensor data on operation of engine, performance of airplane, and conditions in atmosphere. No data recorded on aircraft.
Archival reports on developments in programs managed by the JPL Office of Telecommunications and Data Acquisition (TDA) are provided. Topics covered include: DSN advanced systems (tracking and ground-based navigation; communications, spacecraft-ground; and station control and system technology) and DSN systems implementation (capabilities for existing projects; capabilities for new projects; TDA program management and analysis; and Goldstone solar system radar).