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Saumil N Merchant - One of the best experts on this subject based on the ideXlab platform.

  • Motion of the tympanic membrane after cartilage tympanoplasty determined by stroboscopic holography
    Hearing Research, 2010
    Co-Authors: Antti A Aarnisalo, Cosme Furlong, Jeffrey Cheng, John J Rosowski, Michael E Ravicz, Saumil N Merchant
    Abstract:

    Abstract Stroboscopic holography was used to quantify dynamic deformations of the tympanic membrane (TM) of the entire surface of the TM before and after cartilage tympanoplasty of the posterior or posterior-superior part of the TM. Cartilage is widely used in tympanoplasties to provide mechanical stability for the TM. Three human cadaveric temporal bones were used. A 6 mm × 3 mm oval cartilage graft was placed through the widely opened facial recess onto the medial surface of the posterior or posterior-superior part of the TM. The graft was either in contact with the bony tympanic rim and manubrium or not. Graft thickness was either 0.5 or 1.0 mm. Stroboscopic holography produced displacement amplitude and Phase maps of the TM surface in response to stimulus sound. Sound stimuli were 0.5, 1, 4 and 7 (or 8) kHz tones. Middle-ear impedance was measured from the Motion of the entire TM. Cartilage placement generally produced reductions in the Motion of the TM apposed to the cartilage, especially at 4 kHz and 7 or 8 kHz. Some parts of the TM showed altered Motion compared to the control in all three cases. In general, middle-ear impedance was either unchanged or increased somewhat after cartilage reconstruction both at low (0.5 and 1 kHz) and high (4 and 7 kHz) frequencies. At 4 kHz, with the 1.0 mm thick graft that was in contact with the bony tympanic rim, the impedance slightly decreased. While our earlier work with time-averaged holography allowed us to observe differences in the pattern of TM Motion caused by application of cartilage to the TM, stroboscopic holography is more sensitive to TM Motions and allowed us to quantify the magnitude and Phase of Motion of each point on the TM surface. Nonetheless, our results are similar to those of our earlier work: The placement of cartilage on the medial surface of TM reduces the Motion of the TM that apposes the cartilage. These obvious local changes occur even though the cartilage had little effect on the sound-induced Motion of the stapes.

John J Rosowski - One of the best experts on this subject based on the ideXlab platform.

  • shape and 3d acoustically induced vibrations of the human eardrum characterized by digital holography
    Proceedings of SPIE, 2014
    Co-Authors: Morteza Khaleghi, Cosme Furlong, Jeffrey Cheng, John J Rosowski
    Abstract:

    The eardrum or Tympanic Membrane (TM) transfers acoustic energy from the ear canal (at the external ear) into mechanical Motions of the ossicles (at the middle ear). The acousto-mechanical-transformer behavior of the TM is determined by its shape and mechanical properties. For a better understanding of hearing mysteries, full-field-of-view techniques are required to quantify shape, nanometer-scale sound-induced displacement, and mechanical properties of the TM in 3D. In this paper, full-field-of-view, three-dimensional shape and sound-induced displacement of the surface of the TM are obtained by the methods of multiple wavelengths and multiple sensitivity vectors with lensless digital holography. Using our developed digital holographic systems, unique 3D information such as, shape (with micrometer resolution), 3D acoustically-induced displacement (with nanometer resolution), full strain tensor (with nano-strain resolution), 3D Phase of Motion, and 3D directional cosines of the displacement vectors can be obtained in full-field-ofview with a spatial resolution of about 3 million points on the surface of the TM and a temporal resolution of 15 Hz.

  • Motion of the tympanic membrane after cartilage tympanoplasty determined by stroboscopic holography
    Hearing Research, 2010
    Co-Authors: Antti A Aarnisalo, Cosme Furlong, Jeffrey Cheng, John J Rosowski, Michael E Ravicz, Saumil N Merchant
    Abstract:

    Abstract Stroboscopic holography was used to quantify dynamic deformations of the tympanic membrane (TM) of the entire surface of the TM before and after cartilage tympanoplasty of the posterior or posterior-superior part of the TM. Cartilage is widely used in tympanoplasties to provide mechanical stability for the TM. Three human cadaveric temporal bones were used. A 6 mm × 3 mm oval cartilage graft was placed through the widely opened facial recess onto the medial surface of the posterior or posterior-superior part of the TM. The graft was either in contact with the bony tympanic rim and manubrium or not. Graft thickness was either 0.5 or 1.0 mm. Stroboscopic holography produced displacement amplitude and Phase maps of the TM surface in response to stimulus sound. Sound stimuli were 0.5, 1, 4 and 7 (or 8) kHz tones. Middle-ear impedance was measured from the Motion of the entire TM. Cartilage placement generally produced reductions in the Motion of the TM apposed to the cartilage, especially at 4 kHz and 7 or 8 kHz. Some parts of the TM showed altered Motion compared to the control in all three cases. In general, middle-ear impedance was either unchanged or increased somewhat after cartilage reconstruction both at low (0.5 and 1 kHz) and high (4 and 7 kHz) frequencies. At 4 kHz, with the 1.0 mm thick graft that was in contact with the bony tympanic rim, the impedance slightly decreased. While our earlier work with time-averaged holography allowed us to observe differences in the pattern of TM Motion caused by application of cartilage to the TM, stroboscopic holography is more sensitive to TM Motions and allowed us to quantify the magnitude and Phase of Motion of each point on the TM surface. Nonetheless, our results are similar to those of our earlier work: The placement of cartilage on the medial surface of TM reduces the Motion of the TM that apposes the cartilage. These obvious local changes occur even though the cartilage had little effect on the sound-induced Motion of the stapes.

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

  • Variable impedance control in Cartesian latent space while avoiding obstacles in null space
    'Japanese Society of Applied Entomology & Zoology', 2020
    Co-Authors: Parent Alonso David, Colomé Adrià, Torras Carme
    Abstract:

    Trabajo presentado en la IEEE International Conference on Robotics and Automation (ICRA), conferencia virtual celebrada del 31 de mayo al 31 de agosto de 2020Human-robot interaction is one of the keys of assistive robots. Robots are expected to be compliant with people but at the same time correctly perform the tasks. In such applications, Cartesian impedance control is preferred over joint control, as the desired interaction and environmental feedback can be described more naturally, and the force to be exerted by the robot can be readily adjusted. This paper addresses the problem of controlling a robot arm in the operational space with variable stiffness so as to continuously adapt the force exerted in each Phase of Motion according to the precision requirements. Moreover, performing dimensionality reduction we can separate the degrees of freedom (Dof) relevant for the task from the redundant ones. The stiffness of the former can be adjusted constantly to achieve the required accuracy, while task-redundant Dof can be used to achieve other goals such as avoiding obstacles by moving in the directions where accuracy is not critical. The designed method is tested teaching the robot to give water to drink to a model of human head. Our empirical results demonstrate that the robot can learn precision requirements from demonstration. Furthermore, dimensionality reduction is proved to be useful to avoid obstacles.This work was partially developed in the context of the project CLOTHILDE ("CLOTH manIpulation Learning from DEmonstrations"), which has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (Advanced Grant agreement No 741930). This work is also supported by the Spanish State Research Agency through the María de Maeztu Seal of Excellence to IRI MdM-IP-2018-05.Peer reviewe

  • Variable impedance control in cartesian latent space while avoiding obstacles in null space
    'Institute of Electrical and Electronics Engineers (IEEE)', 2020
    Co-Authors: Parent Alonso David, Colomé Figueras Adrià, Torras Carme
    Abstract:

    © 2020 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or proMotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.Human-robot interaction is one of the keys of assistive robots. Robots are expected to be compliant with people but at the same time correctly perform the tasks. In such applications, Cartesian impedance control is preferred over joint control, as the desired interaction and environmental feedback can be described more naturally, and the force to be exerted by the robot can be readily adjusted. This paper addresses the problem of controlling a robot arm in the operational space with variable stiffness so as to continuously adapt the force exerted in each Phase of Motion according to the precision requirements. Moreover, performing dimensionality reduction we can separate the degrees of freedom (Dof) relevant for the task from the redundant ones. The stiffness of the former can be adjusted constantly to achieve the required accuracy, while task-redundant Dof can be used to achieve other goals such as avoiding obstacles by moving in the directions where accuracy is not critical. The designed method is tested teaching the robot to give water to drink to a model of human head. Our empirical results demonstrate that the robot can learn precision requirements from demonstration. Furthermore, dimensionality reduction is proved to be useful to avoid obstacles.This work was partially developed in the context of the project CLOTHILDE ("CLOTH manIpulation Learning from DEmonstrations"),which has received funding from the European Research Council (ERC) underthe European Union’s Horizon 2020 research and innovation programme(Advanced Grant agreement No 741930). This work is also supported bythe Spanish State Research Agency through the María de Maeztu Seal ofExcellence to IRI MdM-IP-2018-05.Peer ReviewedPostprint (author's final draft

Parent Alonso David - One of the best experts on this subject based on the ideXlab platform.

  • Variable impedance control in Cartesian latent space while avoiding obstacles in null space
    'Japanese Society of Applied Entomology & Zoology', 2020
    Co-Authors: Parent Alonso David, Colomé Adrià, Torras Carme
    Abstract:

    Trabajo presentado en la IEEE International Conference on Robotics and Automation (ICRA), conferencia virtual celebrada del 31 de mayo al 31 de agosto de 2020Human-robot interaction is one of the keys of assistive robots. Robots are expected to be compliant with people but at the same time correctly perform the tasks. In such applications, Cartesian impedance control is preferred over joint control, as the desired interaction and environmental feedback can be described more naturally, and the force to be exerted by the robot can be readily adjusted. This paper addresses the problem of controlling a robot arm in the operational space with variable stiffness so as to continuously adapt the force exerted in each Phase of Motion according to the precision requirements. Moreover, performing dimensionality reduction we can separate the degrees of freedom (Dof) relevant for the task from the redundant ones. The stiffness of the former can be adjusted constantly to achieve the required accuracy, while task-redundant Dof can be used to achieve other goals such as avoiding obstacles by moving in the directions where accuracy is not critical. The designed method is tested teaching the robot to give water to drink to a model of human head. Our empirical results demonstrate that the robot can learn precision requirements from demonstration. Furthermore, dimensionality reduction is proved to be useful to avoid obstacles.This work was partially developed in the context of the project CLOTHILDE ("CLOTH manIpulation Learning from DEmonstrations"), which has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (Advanced Grant agreement No 741930). This work is also supported by the Spanish State Research Agency through the María de Maeztu Seal of Excellence to IRI MdM-IP-2018-05.Peer reviewe

  • Variable impedance control in cartesian latent space while avoiding obstacles in null space
    'Institute of Electrical and Electronics Engineers (IEEE)', 2020
    Co-Authors: Parent Alonso David, Colomé Figueras Adrià, Torras Carme
    Abstract:

    © 2020 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or proMotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.Human-robot interaction is one of the keys of assistive robots. Robots are expected to be compliant with people but at the same time correctly perform the tasks. In such applications, Cartesian impedance control is preferred over joint control, as the desired interaction and environmental feedback can be described more naturally, and the force to be exerted by the robot can be readily adjusted. This paper addresses the problem of controlling a robot arm in the operational space with variable stiffness so as to continuously adapt the force exerted in each Phase of Motion according to the precision requirements. Moreover, performing dimensionality reduction we can separate the degrees of freedom (Dof) relevant for the task from the redundant ones. The stiffness of the former can be adjusted constantly to achieve the required accuracy, while task-redundant Dof can be used to achieve other goals such as avoiding obstacles by moving in the directions where accuracy is not critical. The designed method is tested teaching the robot to give water to drink to a model of human head. Our empirical results demonstrate that the robot can learn precision requirements from demonstration. Furthermore, dimensionality reduction is proved to be useful to avoid obstacles.This work was partially developed in the context of the project CLOTHILDE ("CLOTH manIpulation Learning from DEmonstrations"),which has received funding from the European Research Council (ERC) underthe European Union’s Horizon 2020 research and innovation programme(Advanced Grant agreement No 741930). This work is also supported bythe Spanish State Research Agency through the María de Maeztu Seal ofExcellence to IRI MdM-IP-2018-05.Peer ReviewedPostprint (author's final draft

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

  • shape and 3d acoustically induced vibrations of the human eardrum characterized by digital holography
    Proceedings of SPIE, 2014
    Co-Authors: Morteza Khaleghi, Cosme Furlong, Jeffrey Cheng, John J Rosowski
    Abstract:

    The eardrum or Tympanic Membrane (TM) transfers acoustic energy from the ear canal (at the external ear) into mechanical Motions of the ossicles (at the middle ear). The acousto-mechanical-transformer behavior of the TM is determined by its shape and mechanical properties. For a better understanding of hearing mysteries, full-field-of-view techniques are required to quantify shape, nanometer-scale sound-induced displacement, and mechanical properties of the TM in 3D. In this paper, full-field-of-view, three-dimensional shape and sound-induced displacement of the surface of the TM are obtained by the methods of multiple wavelengths and multiple sensitivity vectors with lensless digital holography. Using our developed digital holographic systems, unique 3D information such as, shape (with micrometer resolution), 3D acoustically-induced displacement (with nanometer resolution), full strain tensor (with nano-strain resolution), 3D Phase of Motion, and 3D directional cosines of the displacement vectors can be obtained in full-field-ofview with a spatial resolution of about 3 million points on the surface of the TM and a temporal resolution of 15 Hz.

  • Motion of the tympanic membrane after cartilage tympanoplasty determined by stroboscopic holography
    Hearing Research, 2010
    Co-Authors: Antti A Aarnisalo, Cosme Furlong, Jeffrey Cheng, John J Rosowski, Michael E Ravicz, Saumil N Merchant
    Abstract:

    Abstract Stroboscopic holography was used to quantify dynamic deformations of the tympanic membrane (TM) of the entire surface of the TM before and after cartilage tympanoplasty of the posterior or posterior-superior part of the TM. Cartilage is widely used in tympanoplasties to provide mechanical stability for the TM. Three human cadaveric temporal bones were used. A 6 mm × 3 mm oval cartilage graft was placed through the widely opened facial recess onto the medial surface of the posterior or posterior-superior part of the TM. The graft was either in contact with the bony tympanic rim and manubrium or not. Graft thickness was either 0.5 or 1.0 mm. Stroboscopic holography produced displacement amplitude and Phase maps of the TM surface in response to stimulus sound. Sound stimuli were 0.5, 1, 4 and 7 (or 8) kHz tones. Middle-ear impedance was measured from the Motion of the entire TM. Cartilage placement generally produced reductions in the Motion of the TM apposed to the cartilage, especially at 4 kHz and 7 or 8 kHz. Some parts of the TM showed altered Motion compared to the control in all three cases. In general, middle-ear impedance was either unchanged or increased somewhat after cartilage reconstruction both at low (0.5 and 1 kHz) and high (4 and 7 kHz) frequencies. At 4 kHz, with the 1.0 mm thick graft that was in contact with the bony tympanic rim, the impedance slightly decreased. While our earlier work with time-averaged holography allowed us to observe differences in the pattern of TM Motion caused by application of cartilage to the TM, stroboscopic holography is more sensitive to TM Motions and allowed us to quantify the magnitude and Phase of Motion of each point on the TM surface. Nonetheless, our results are similar to those of our earlier work: The placement of cartilage on the medial surface of TM reduces the Motion of the TM that apposes the cartilage. These obvious local changes occur even though the cartilage had little effect on the sound-induced Motion of the stapes.