The Experts below are selected from a list of 87510 Experts worldwide ranked by ideXlab platform

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

  • Vision-based Force Measurement
    IEEE Transactions on Pattern Analysis and Machine Intelligence, 2004
    Co-Authors: M.a. Greminger, B.j. Nelson
    Abstract:

    This paper demonstrates a method to visually measure the Force distribution applied to a linearly elastic object using the contour data in an image. The Force Measurement is accomplished by making use of the result from linear elasticity that the displacement field of the contour of a linearly elastic object is sufficient to completely recover the Force distribution applied to the object. This result leads naturally to a deformable template matching approach where the template is deformed according to the governing equations of linear elasticity. An energy minimization method is used to match the template to the contour data in the image. This technique of visually measuring Forces we refer to as vision-based Force Measurement (VBFM). VBFM has the potential to increase the robustness and reliability of micromanipulation and biomanipulation tasks where Force sensing is essential for success. The effectiveness of VBFM is demonstrated for both a microcantilever beam and a microgripper. A sensor resolution of less than +/-3 nN for the microcantilever and +/-3 mN for the microgripper was achieved using VBFM. Performance optimizations for the energy minimization problem are also discussed that make this algorithm feasible for real-time applications.

M.a. Greminger - One of the best experts on this subject based on the ideXlab platform.

  • Vision-based Force Measurement
    IEEE Transactions on Pattern Analysis and Machine Intelligence, 2004
    Co-Authors: M.a. Greminger, B.j. Nelson
    Abstract:

    This paper demonstrates a method to visually measure the Force distribution applied to a linearly elastic object using the contour data in an image. The Force Measurement is accomplished by making use of the result from linear elasticity that the displacement field of the contour of a linearly elastic object is sufficient to completely recover the Force distribution applied to the object. This result leads naturally to a deformable template matching approach where the template is deformed according to the governing equations of linear elasticity. An energy minimization method is used to match the template to the contour data in the image. This technique of visually measuring Forces we refer to as vision-based Force Measurement (VBFM). VBFM has the potential to increase the robustness and reliability of micromanipulation and biomanipulation tasks where Force sensing is essential for success. The effectiveness of VBFM is demonstrated for both a microcantilever beam and a microgripper. A sensor resolution of less than +/-3 nN for the microcantilever and +/-3 mN for the microgripper was achieved using VBFM. Performance optimizations for the energy minimization problem are also discussed that make this algorithm feasible for real-time applications.

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

  • A novel technique for aerodynamic Force Measurement in shock tubes
    AIP Conference Proceedings, 2008
    Co-Authors: K.w. Naumann, Haji Ende, G. Mathieu
    Abstract:

    For aerodynamic Force Measurement in the ISL shock tunnel we have developed a novel Measurement technique. Its key feature is a mounting support, which releases the test model and tightens it again after a free flight duration of 10 to 15 milliseconds. This short time of free flight allows for the installation of wirings, because the model travels only some millimeters within the test time. Thus we may record the accelerations directly, and as no restraint is effective, up to 6 components. This paper describes the function cycle of the mounting support, model instrumentation and the first tests in the ISL shock tunnel.

  • Millisecond Aerodynamic Force Measurement Technique for High-Enthalpy Test Facilities
    New Trends in Instrumentation for Hypersonic Research, 1993
    Co-Authors: K.w. Naumann, Haji Ende, G. Mathieu
    Abstract:

    For aerodynamic Force Measurement in short duration aerodynamic testing facilities we have developed a novel Measurement technique. A fast-acting mounting support releases the model and grips it again after a free flight duration of some milliseconds. The model is equipped with accelerometers and may contain additional installations. Pitot pressure Measurement and suitable data processing allow for direct straightforward time-dependent evaluation of the aerodynamic coefficients. This procedure is insensitive against nonlinearities or disturbances in the starting phase of the flow and compensates flow variations, if the flow is quasistationary and maintains a roughly uniform Mach number. The paper presents the measuring technique and, for example, experiments with a simple cone-cylinder model and with a body-wing model with built-in side-jets.

  • technique for aerodynamic Force Measurement within milliseconds in shock tunnel
    Shock Waves, 1991
    Co-Authors: K.w. Naumann, Haji Ende, G. Mathieu
    Abstract:

    For aerodynamic Force Measurement in shock tunnels and similar short duration aerodynamic testing facilities we have developed a novel Measurement technique. Its key feature is a mounting support, which releases the test model and grips it again after a free flight duration of about 10 milliseconds. The model is equipped with small accelerometers and may contain additional installations. The short free flight allows the use of thin wires because the model travels only a few millimeters during this time. Validation experiments with a cone-cylinder of known drag coefficient show good accuracy with a response time of about half a millisecond. Pitot pressure Measurement and suitable data processing allow for direct evaluation of aerodynamic coefficients in slowly changing flow.

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

  • Improving the aerodynamic Force Measurement system for the USQ gun tunnel
    2004
    Co-Authors: Timothy Davidson
    Abstract:

    The accurate landing of entry capsules on other planets and moons depends on accurate knowledge of the aerodynamic behavior of the landing vehicle. The problem is that at the hypersonic speeds that are experienced by entry capsules during atmospheric entry, it is very hard to predict the capsule's behavior. This project, The Measurement of Entry Capsule Aerodynamic Force Coefficient aims to improve the original aerodynamic Force Measurement system that is used in the University of Southern Queensland Gun Tunnel. After an analysis of the previous method of Force Measurement and a review of other Force Measurement systems a new system was designed for the Gun Tunnel. This will allow for the prediction of normal and axial Forces on an entry capsule model, as well as the location of the centre of pressure. The first test run of this project aimed to identify the aerodynamic Forces acting on the Japanese, MUSES-C Entry Capsule during a Mach 7 flow in the USQ Gun Tunnel. During this test only the axial Force was measured. This Force was then compared to a prediction based on a Newtonian Flow model.

  • Improving the aerodynamic Force Measurement system for the USQ gun tunnel
    2004
    Co-Authors: Timothy Davidson
    Abstract:

    The accurate landing of entry capsules on other planets and moons depends on accurate knowledge of the aerodynamic behavior of the landing vehicle. The problem is that at the hypersonic speeds that are experienced by entry capsules during atmospheric entry, it is very hard to predict the capsule's behavior. This project, The Measurement of Entry Capsule Aerodynamic Force Coefficient aims to improve the original aerodynamic Force Measurement system that is used in the University of Southern Queensland Gun Tunnel. After an analysis of the previous method of Force Measurement and a review of other Force Measurement systems a new system was designed for the Gun Tunnel. This will allow for the prediction of normal and axial Forces on an entry capsule model, as well as the location of the centre of pressure. The first test run of this project aimed to identify the aerodynamic Forces acting on the Japanese, MUSES-C Entry Capsule during a Mach 7 flow in the USQ Gun Tunnel. During this test only the axial Force was measured. This Force was then compared to a prediction based on a Newtonian Flow model.

K.w. Naumann - One of the best experts on this subject based on the ideXlab platform.

  • A novel technique for aerodynamic Force Measurement in shock tubes
    AIP Conference Proceedings, 2008
    Co-Authors: K.w. Naumann, Haji Ende, G. Mathieu
    Abstract:

    For aerodynamic Force Measurement in the ISL shock tunnel we have developed a novel Measurement technique. Its key feature is a mounting support, which releases the test model and tightens it again after a free flight duration of 10 to 15 milliseconds. This short time of free flight allows for the installation of wirings, because the model travels only some millimeters within the test time. Thus we may record the accelerations directly, and as no restraint is effective, up to 6 components. This paper describes the function cycle of the mounting support, model instrumentation and the first tests in the ISL shock tunnel.

  • Millisecond Aerodynamic Force Measurement Technique for High-Enthalpy Test Facilities
    New Trends in Instrumentation for Hypersonic Research, 1993
    Co-Authors: K.w. Naumann, Haji Ende, G. Mathieu
    Abstract:

    For aerodynamic Force Measurement in short duration aerodynamic testing facilities we have developed a novel Measurement technique. A fast-acting mounting support releases the model and grips it again after a free flight duration of some milliseconds. The model is equipped with accelerometers and may contain additional installations. Pitot pressure Measurement and suitable data processing allow for direct straightforward time-dependent evaluation of the aerodynamic coefficients. This procedure is insensitive against nonlinearities or disturbances in the starting phase of the flow and compensates flow variations, if the flow is quasistationary and maintains a roughly uniform Mach number. The paper presents the measuring technique and, for example, experiments with a simple cone-cylinder model and with a body-wing model with built-in side-jets.

  • technique for aerodynamic Force Measurement within milliseconds in shock tunnel
    Shock Waves, 1991
    Co-Authors: K.w. Naumann, Haji Ende, G. Mathieu
    Abstract:

    For aerodynamic Force Measurement in shock tunnels and similar short duration aerodynamic testing facilities we have developed a novel Measurement technique. Its key feature is a mounting support, which releases the test model and grips it again after a free flight duration of about 10 milliseconds. The model is equipped with small accelerometers and may contain additional installations. The short free flight allows the use of thin wires because the model travels only a few millimeters during this time. Validation experiments with a cone-cylinder of known drag coefficient show good accuracy with a response time of about half a millisecond. Pitot pressure Measurement and suitable data processing allow for direct evaluation of aerodynamic coefficients in slowly changing flow.