The Experts below are selected from a list of 321 Experts worldwide ranked by ideXlab platform

Steven E Shladover - One of the best experts on this subject based on the ideXlab platform.

  • Cooperative Adaptive Cruise Control (CACC) for Truck Platooning: Operational Concept Alternatives
    2015
    Co-Authors: Christopher Nowakowski, Steven E Shladover, Deborah Thompson, Aravind Kailas
    Abstract:

    Cooperative Adaptive Cruise Control (CACC) provides an intermediate step toward a longer-term vision of trucks operating in closely-coupled automated platoons. There are important distinctions between CACC and automated truck platooning. First, with CACC, only truck speed control will be automated, using vehicle to vehicle (V2V) communication to supplement forward sensors. The drivers will still be responsible for actively steering the vehicle, lane keeping, and monitoring roadway and traffic conditions. Second, while truck platooning systems have relied on a Constant Distance Gap (CDG) control strategy, CACC has relied on a Constant-Time Gap (CTG) control strategy, where the distance between vehicles is proportional to the speed. For these reasons, a series of trucks using CACC is referred to as a string, rather than a platoon. This report mainly focuses on describing the various CACC Operational Concept alternatives at the level of individual vehicles, local groups of vehicles and their drivers, and which alternatives should be employed in this research project. These Operational Concepts can be broken into four categories: string formation, steady-state cruising, string split maneuvers, and faults or abnormal operating conditions.

  • truck automation Operational Concept alternatives
    IEEE Intelligent Vehicles Symposium, 2010
    Co-Authors: Steven E Shladover
    Abstract:

    This paper defines a comprehensive range of Operational Concepts for automating the driving of heavy trucks. These Concepts are defined in terms of the amount of driving functionality that is transferred from the driver to the automated system and the roadway conditions in which the trucks would operate. With the minimum amount of automation (providing only safety warnings to drivers) it should be feasible and safe to operate in any roadway environment, but with the maximum use of automation operations must be restricted to simplified and protected driving environments to keep the complexity of the automation challenges tractable. This systematic classification of Operational Concept alternatives is intended to help stakeholders who are interested in truck automation to focus on specific alternatives.

  • Intelligent Vehicles Symposium - Truck automation Operational Concept alternatives
    2010 IEEE Intelligent Vehicles Symposium, 2010
    Co-Authors: Steven E Shladover
    Abstract:

    This paper defines a comprehensive range of Operational Concepts for automating the driving of heavy trucks. These Concepts are defined in terms of the amount of driving functionality that is transferred from the driver to the automated system and the roadway conditions in which the trucks would operate. With the minimum amount of automation (providing only safety warnings to drivers) it should be feasible and safe to operate in any roadway environment, but with the maximum use of automation operations must be restricted to simplified and protected driving environments to keep the complexity of the automation challenges tractable. This systematic classification of Operational Concept alternatives is intended to help stakeholders who are interested in truck automation to focus on specific alternatives.

  • bicycle detection and Operational Concept at signalized intersections
    PATH research report, 2009
    Co-Authors: Steven E Shladover, Zuwhan Kim, Meng Cao, Ashkan Sharafsaleh, Kai Leung
    Abstract:

    Based on the detailed quantitative characterizations of bicyclist speeds and start-up times at signalized intersections, sample signal timing criteria have been defined to accommodate the 50 percentile, 80 percentile and 90 percentile of bicyclists. The results indicate the soundness of the basic approach, but with a recommendation to account for all the relevant explanatory variables, including the bicycling population, roadway grade, mainline traffic speed and volume and the visibility of the mainline traffic by the bicyclists waiting to cross, in addition to the intersection width, in order to produce fully consistent results. A traffic microsimulation of a high-volume suburban arterial corridor has been used to show that moderate increases in the minimum green time for cross streets should have a negligible impact on delays and queuing along the mainline arterial. Experiments were conducted to determine the ability of commercially available traffic detection systems to detect a minimum-size bicycle with a minimum

Douglas Meyerhoff - One of the best experts on this subject based on the ideXlab platform.

Derek Fowler - One of the best experts on this subject based on the ideXlab platform.

Harold Nelson - One of the best experts on this subject based on the ideXlab platform.

  • National Airspace System: System Effectiveness Operational Concept NAS- SR-138
    1992
    Co-Authors: William Trent, Thomas Pickerell, Harold Nelson
    Abstract:

    Abstract : A requirement for the National Airspace System (NAS) is to provide for system effectiveness as identified in the NAS System Requirements Specification (NASSRS). This Operational Concept is one of many high level documents that will, in total, describe the operation of the NAS when the projected upgrade is complete (i.e., "end state"). These documents will assist in linking the requirements specified in the NASSRS with the NAS design. This particular Concept describes system effectiveness as described in paragraph 3.8 of the NASSRS, including the following four paragraphs: 3.8.1 Operational Readiness, 3.8.2 Response Times, 3.8.3 Immediate Backup, and 3.8.4 Security. This Concept, and the other seven Operational Concepts, will complete the description of the system requirements as described in the NASSRS. The eight Operational Concepts are: Communications (NAS-SR-136); Navigation (NAS-SR-134); Monitoring (NAS-SR-133); Maintenance and Support (NAS-SR-137); System Effectiveness (NAS-SR-138); Air Defense (NAS-SR-135); Flight Planning (NAS-SR- 131); and Traffic Control and Airspace Management (NAS-SR-132). Operational readiness, Response times, Immediate backup, Security.

  • National Airspace System: Maintenance and Support Operational Concept NAS-SR-137
    1992
    Co-Authors: William Trent, Thomas Pickerell, Harold Nelson
    Abstract:

    Abstract : A requirement for the National Airspace System (NAS) is to provide for the maintenance and support of the NAS. This document presents a Concept of operations for maintenance and support. It describes these capabilities and shows the relationships between subsystems, facilities, information, and operators/users. It is intended to provide a common perspective for personnel involved in maintenance and support services, assist in determining whether procedures meet formal requirements, and support coordination among the organizations involved. This Concept, along with seven other Operational Concepts, will complete the description of the system requirements as described in the NASSRS.

  • National Airspace System: Monitoring Operational Concept NAS-SR-133
    1991
    Co-Authors: William Trent, Thomas Pickerell, Harold Nelson
    Abstract:

    Abstract : A requirement for the National Airspace System (NAS) is to provide a variety of monitoring services to its users, as identified in the NAS System Requirement Specification, NAS-SR-1000. This document presents a Concept of operations for monitoring. It describes monitoring capabilities and shows the relationships between subsystems, facilities, information, and operators/users. It is intended to provide a common perspective for personnel involved in monitoring services, assist in determining whether monitoring procedures meet formal requirements, and support coordination among the organizations involved. This Concept, and the other seven Operational Concepts, will complete the description of the system requirements as described in the NASSRS. The eight Operational Concepts are: Communications (NAS-SR-136); Navigation (NAS-SR-134); Monitoring (NAS-SR-133); Maintenance and Support (NAS-SR-137); System Effectiveness (NAS-SR-138); Air Defense (NAS-SR-135); Flight Planning (NAS-SR- 131); and Traffic Control and Airspace Management (NAS-SR-132).

  • Navigation Operational Concept
    1991
    Co-Authors: William Trent, Thomas Pickerell, Harold Nelson
    Abstract:

    Abstract : A requirement for the National Airspace (NAS) is to provide for navigation, as identified in the NAS System Requirement Specification (NASSRS). This Operational Concept is one of many high level documents that will, in total, describe the operation of the NAS when the projected upgrade is complete. These documents will assist in linking the requirements specified in the NASSRS with the NAS design. This particular Concept describes navigation as specified in paragraph 3.4 of the NASSRS, including paragraphs 3.4.1 Enroute Navigation; 3.4.2 terminal Navigation; and 3.4.3 Visual Navigational Aids. The eight Operational Concepts are: Communication, Navigation, Monitoring, Maintenance and Support, System Effectiveness, Air Defense, Flight Planning and Traffic Control, and Airspace Management.

  • National Airspace System Communications Operational Concept
    1991
    Co-Authors: William Trent, Thomas Pickerell, Harold Nelson
    Abstract:

    Abstract : A requirement for the National Airspace System (NAS) is to provide for communications, as identified in the NAS System Requirement Specification, NAS-SR-1000 (NASSRS). This document presents a Concept of operation for air- ground, ground-ground communications connectivity and capability, and national emergency communications. This Concept describes the capabilities and shows the relationships between subsystems, facilities, information, and operators/users. It is intended to provide a common perspective for personnel involved in communication activities, assist in determining whether communications meet formal requirements, and support coordination among the organizations involved. This Concept describes communications as specified in paragraph 3.6 of the NASSRS including paragraphs 3.6.1, 3.6.2, 3.6.3, and 3.6.4. This Concept is one of eight Operational Concepts. The remaining yet to be written Concepts will complete the description of the system requirements as detailed in the NASSRS. The eight Operational Concepts are: Communications (NAS-SR-136); Navigation (NAS-SR-134); Monitoring (NAS-SR-133); Maintenance and Support (NAS-SR-137); System Effectiveness (NAS-SR-138); Air Defense (NAS-SR-135); Flight Planning (NAS-SR-131); and Support of Military Operation (NAS-SR-3.2.10).

Christopher A Jones - One of the best experts on this subject based on the ideXlab platform.

  • high altitude venus Operational Concept havoc an exploration strategy for venus
    AIAA SPACE 2015 Conference and Exposition, 2015
    Co-Authors: Dale Arney, Christopher A Jones
    Abstract:

    Humans are on their way to becoming a spacefaring civilization, and Venus presents an intriguing destination for expanding humanity’s journey beyond Earth. The atmosphere of Venus is a suitable environment for both further scientific study and future human exploration. Fifty kilometers above the Venusian surface is one of the most hospitable, Earthlike locations in the Solar System; the pressure, density, gravity, and radiation protection are all similar to Earth surface conditions. A recent internal NASA study of a High Altitude Venus Operational Concept (HAVOC) led to the development of an evolutionary program for the exploration of Venus, with a focus on the mission architecture and vehicle Concepts for robotic missions and 30-day crewed missions into the Venusian atmosphere. Initial analysis has shown that both robotic and human exploration of the Venusian atmosphere is feasible contingent on the development of key capabilities: human-scale aeroentry vehicles, high dynamic pressure supersonic decelerators, long-duration cryogenic storage, Venus and Earth aerocapture, and rapid airship inflation (during the descent). Many of these capabilities are complementary to previously and currently considered Mars architectures, and their development would be enabling to voyages to either planet. Ultimately, with its relatively hospitable upper atmosphere, Venus can play a role in humanity’s future in space.

  • High Altitude Venus Operational Concept (HAVOC): Proofs of Concept
    AIAA SPACE 2015 Conference and Exposition, 2015
    Co-Authors: Christopher A Jones, Dale Arney, George Z. Bassett, Anthony I. Hennig, James R. Clark, Jessica C. Snyder
    Abstract:

    The atmosphere of Venus is an exciting destination for both further scientific study and future human exploration. A recent internal NASA study of a High Altitude Venus Operational Concept (HAVOC) led to the development of an evolutionary program for the exploration of Venus, with focus on the mission architecture and vehicle Concept for a 30-day crewed mission into Venus’s atmosphere at 50 km. Key technical challenges for the mission include performing the aerocapture maneuvers at Venus and Earth, inserting and inflating the airship at Venus during the entry sequence, and protecting the solar panels and structure from the sulfuric acid in the atmosphere. Two proofs of Concept were identified that would aid in addressing some of the key technical challenges. To mitigate the threat posed by the sulfuric acid ambient in the atmosphere of Venus, a material was needed that could protect the systems while being lightweight and not inhibiting the performance of the solar panels. The first proof of Concept identified candidate materials and evaluated them, finding FEPteflon to maintain 90% transmittance to relevant spectra even after 30 days of immersion in concentrated sulfuric acid. The second proof of Concept developed and verified a packaging algorithm for the airship envelope to inform the entry, descent, and inflation analysis.

  • High Altitude Venus Operational Concept (HAVOC): Proofs of Concept
    AIAA SPACE 2015 Conference and Exposition, 2015
    Co-Authors: Christopher A Jones, Dale Arney, George Z. Bassett, Anthony I. Hennig, James R. Clark, Jessica C. Snyder
    Abstract:

    The atmosphere of Venus is an exciting destination for both further scientific study and future human exploration. A recent internal NASA study of a High Altitude Venus Operational Concept (HAVOC) led to the development of an evolutionary program for the exploration of Venus, with focus on the mission architecture and vehicle Concept for a 30-day crewed mission into Venus's atmosphere at 50 kilometers. Key technical challenges for the mission include performing the aerocapture maneuvers at Venus and Earth, inserting and inflating the airship at Venus during the entry sequence, and protecting the solar panels and structure from the sulfuric acid in the atmosphere. Two proofs of Concept were identified that would aid in addressing some of the key technical challenges. To mitigate the threat posed by the sulfuric acid ambient in the atmosphere of Venus, a material was needed that could protect the systems while being lightweight and not inhibiting the performance of the solar panels. The first proof of Concept identified candidate materials and evaluated them, finding FEP-Teflon (Fluorinated Ethylene Propylene-Teflon) to maintain 90 percent transmittance to relevant spectra even after 30 days of immersion in concentrated sulfuric acid. The second proof of Concept developed and verified a packaging algorithm for the airship envelope to inform the entry, descent, and inflation analysis.