The Experts below are selected from a list of 207 Experts worldwide ranked by ideXlab platform

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

  • Technology assessment of advanced automation for space missions
    2016
    Co-Authors: Nasa
    Abstract:

    Six general classes of technology requirements derived during the mission Definition Phase of the study were identified as having maximum importance and urgency, including autonomous world model based information systems, learning and hypothesis formation, natural language and other man-machine communication, space manufacturing, teleoperators and robot systems, and computer science and technology.

  • Earth Observatory Satellite (EOS) Definition Phase Report, Volume 1
    2014
    Co-Authors: Nasa
    Abstract:

    System Definition studies were conducted of the Earth Observatory Satellite (EOS). The studies show that the concept of an Earth Observatory Satellite in a near-earth, sun-synchronous orbit would make a unique contribution to the goals of a coordinated program for acquisition of data for environmental research with applications to earth resource inventory and management. The technical details for the proposed development of sensors, spacecraft, and a ground data processing system are presented.

  • Activities conducted during the Definition Phase of the outer planets missions program
    2013
    Co-Authors: Nasa
    Abstract:

    The activities are described of the Meteoroid Science Team for the Definition Phase of the outer planet missions. Studies reported include: (1) combined zodiacal experiment for the Grand Tour Missions of the outer planets, (2) optical transmission of a honeycomb panel and its effectiveness as a particle impact surface, (3) element identification data from the combined zodiacal OPGT experiment and (4) development of lightweight thermally stable mirrors.

  • Photopolarimetry team outer planets mission Definition Phase
    2013
    Co-Authors: Nasa
    Abstract:

    The work is reported of the Photopolarimetry Team in identifying scientific objectives for photometer/polarimeter experiments for outer planet flyby missions. A discussion of the scientific objectives which can be attained with a photometer/polarimeter experiment, and summaries of the special studies which were performed for the Photopolarimetry Team are presented along with a description of the photometer/polarimeter design which was developed for the Meteoroid Detection Team.

  • Experiment Definition Phase shuttle laboratory LDRL-10.6 experiment
    2013
    Co-Authors: Nasa
    Abstract:

    Progress is reported in the development of the space shuttle laboratory laser data relay link. The system transmittance of various surfaces was considered in order to examine the coating tradeoffs for the beryllium mirrors. The results of six coating combinations considered are summarized. It is recommended that silver coatings be used throughout the system. Design of the pre-expander and a preliminary alignment procedure implemented to align all optical elements to the reference mechanical axis (the rotational axis of the outer gimbal bearing located between the two Gregorian telescopes) are included. The local oscillator subsystem, consisting of the laser, Stark cell, Stark cell electronics, power supply, starting circuit, and conditioning optics were completed and installed in the optimechanical subsystem and operation against a 10.6 micrometer source was attempted. Preliminary measurements of the HgCdTe mixer showed that this critical element was inoperative and in subsequent tests the receiver front end electronics had also failed. Possible reasons for these failures and corrective action and steps to prevent future recurrence are discussed.

Jean-pierre Micaëlli - One of the best experts on this subject based on the ideXlab platform.

  • A method for jointly drawing up the functional and design architectures of complex systems during the preliminary system-Definition Phase
    Journal of Engineering Design, 2013
    Co-Authors: Eric Bonjour, Samuel Deniaud, Jean-pierre Micaëlli
    Abstract:

    In systems engineering, determining a system's architecture is a crucial part of the preliminary system-Definition Phase because this architecture greatly impacts the quality of the system, the way the subsequent Phases of the design process are organised and the overall performance of this process. Consequently, systems architects need methods for defining the couplings of modules (or sub-systems) and for estimating the impact of allocation decisions on candidate system architectures. This paper presents a method that helps simultaneously define the functional and design architectures of complex systems. Starting from an allocation matrix, or domain mapping matrix, which represents the couplings between the elements of two domains (functions vs. components), the method generates a sesign structure matrix (DSM) for each domain. A clustering algorithm is then applied to each DSM in order to generate a rearranged architecture. This method can be used in the synthesis process to provide architectural output ...

Whitney Aircraft - One of the best experts on this subject based on the ideXlab platform.

  • Space shuttle main engine Definition (Phase B). Volume 2: Avionics
    2013
    Co-Authors: Nasa, Pratt, Whitney Aircraft
    Abstract:

    The advent of the space shuttle engine with its requirements for high specific impulse, long life, and low cost have dictated a combustion cycle and a closed loop control system to allow the engine components to run close to operating limits. These performance requirements, combined with the necessity for low operational costs, have placed new demands on rocket engine control, system checkout, and diagnosis technology. Based on considerations of precision environment, and compatibility with vehicle interface commands, an electronic control, makes available many functions that logically provide the information required for engine system checkout and diagnosis.

H Pouwels - One of the best experts on this subject based on the ideXlab platform.

  • Design and Calibration of the PHARUS Polarimetric Airborne SAR
    1996
    Co-Authors: P Snoeij, P J Koomen, Peter Hoogeboom, B.c.b. Vermeulen, H Pouwels
    Abstract:

    The PHARUS system uses a Phased array antenna with solid state amplifiers. The project consisted of two Phases, a Definition Phase and a realization Phase. The Definition Phase consisted of the actual realization of a SAR research system called PHARS, which made its first successful testflight in November 1990. The research system is based on the concept of a wide beamwidth antenna, rigidly fixed to the aircraft. Pulse compression and a high PRF ensure sufficient sensitivity in this system, which is equipped with a 160 Watt peak pulse power solid state transmitter. The processing is done off-line. In the realization Phase the Polarimetric PHARUS system has been developed. The design is based on the experience gained with the PHARS system. The system uses a Phased array with dual polarized patch radiators and is equipped with solid state amplifiers. This paper will give an overview of the PHARUS design and operational use. Apart from the use as an advanced Polarimetrie airbome SAR, there is the perspective of using PHARUS as a demonstrator for ESA's future ASAR system.

  • The PHARUS project, first results of the realization Phase
    1992
    Co-Authors: P J Koomen, P Snoeij, Peter Hoogeboom, H Pouwels
    Abstract:

    The project (Phased ARray Universal SAR) aims for a polarimetric C-band aircraft SAR, that will be finalized in 1994. This paper gives an overview of the results of the Definition Phase including the first test flights of the SAR testbed. It concludes with the PHARUS pre-design and some results of the realization Phase.

  • the pharus project results of the Definition study including the sar testbed phars
    IEEE Transactions on Geoscience and Remote Sensing, 1992
    Co-Authors: P Hoogeboom, P Snoeij, P J Koomen, H Pouwels
    Abstract:

    The PHARUS (Phased Array Universal SAR) project aims for a polarimetric C-band aircraft synthetic aperture radar (SAR) that will be finalized in 1994. The system will make use of a Phased array antenna with solid-state amplifiers. The project consists of a Definition Phase and a realization Phase. The Definition Phase is intended to increase the knowledge on airborne SAR systems and to develop the critical technology that will be used in the final system. Three preparatory studies were carried out before the PHARUS system was designed. The study on antenna technology and calibration focused on the design of an active Phased array antenna and on the calibration problems involved in using such an antenna. The second study concentrated on motion compensation and the third study consisted of the realization of a SAR testbed. Some results of the Definition Phase, including the results obtained from the first test flights of the SAR testbed, are given. The PHARUS predesign is described. >

Eric Bonjour - One of the best experts on this subject based on the ideXlab platform.

  • A method for jointly drawing up the functional and design architectures of complex systems during the preliminary system-Definition Phase
    Journal of Engineering Design, 2013
    Co-Authors: Eric Bonjour, Samuel Deniaud, Jean-pierre Micaëlli
    Abstract:

    In systems engineering, determining a system's architecture is a crucial part of the preliminary system-Definition Phase because this architecture greatly impacts the quality of the system, the way the subsequent Phases of the design process are organised and the overall performance of this process. Consequently, systems architects need methods for defining the couplings of modules (or sub-systems) and for estimating the impact of allocation decisions on candidate system architectures. This paper presents a method that helps simultaneously define the functional and design architectures of complex systems. Starting from an allocation matrix, or domain mapping matrix, which represents the couplings between the elements of two domains (functions vs. components), the method generates a sesign structure matrix (DSM) for each domain. A clustering algorithm is then applied to each DSM in order to generate a rearranged architecture. This method can be used in the synthesis process to provide architectural output ...