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11. Triage

Author

Michaloux, M., Orsini, J.-P., Nahon, M., and Vivien, B.

Published
2016
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22. Defining Exercise Performance Metrics for Flight Hardware Development

Author

Beyene, Nahon M

Subjects
Aerospace Medicine
Abstract

The space industry has prevailed over numerous design challenges in the spirit of exploration. Manned space flight entails creating products for use by humans and the Johnson Space Center has pioneered this effort as NASA's center for manned space flight. NASA Astronauts use a suite of flight exercise hardware to maintain strength for extravehicular activities and to minimize losses in muscle mass and bone mineral density. With a cycle ergometer, treadmill, and the Resistive Exercise Device available on the International Space Station (ISS), the Space Medicine community aspires to reproduce physical loading schemes that match exercise performance in Earth s gravity. The resistive exercise device presents the greatest challenge with the duty of accommodating 20 different exercises and many variations on the core set of exercises. This paper presents a methodology for capturing engineering parameters that can quantify proper resistive exercise performance techniques. For each specified exercise, the method provides engineering parameters on hand spacing, foot spacing, and positions of the point of load application at the starting point, midpoint, and end point of the exercise. As humans vary in height and fitness levels, the methodology presents values as ranges. In addition, this method shows engineers the proper load application regions on the human body. The methodology applies to resistive exercise in general and is in use for the current development of a Resistive Exercise Device. Exercise hardware systems must remain available for use and conducive to proper exercise performance as a contributor to mission success. The astronauts depend on exercise hardware to support extended stays aboard the ISS. Future plans towards exploration of Mars and beyond acknowledge the necessity of exercise. Continuous improvement in technology and our understanding of human health maintenance in space will allow us to support the exploration of Mars and the future of space exploration.

Published
2004

23. Minimization ofpower losses in cooperating manipulators

Author

Nahon, M. and Angeles, J.

Subjects
Manipulators -- Design and construction, Robots -- Control systems, Actuators -- Design and construction, Engineering and manufacturing industries, Science and technology
Abstract

The control of multiple manipulators handling a common object entails the solution of an underdetermined system of linear equations which represents the system's dynamics. In order to choose an optimal solution to this problem, various approaches have been proposed: minimum internal force and minimum power, among others. The present work investigates an approach for minimizing the power losses in these systems. It is shown that the power imparted to the manipulator/payload system cannot be optimized once the system's motion is prescribed. However, assuming certain loss characteristics for the dc servomotors commonly used on robotic manipulators, it is shown that the minimization of power losses can be cast as a linear-quadratic optimization problem. Local and global performance indices are introduced to allow comparison of the minimum power loss and the minimum internal force approaches. An example of two Puma 560 robots handling a common payload is shown to demonstrate the proposed technique.

Published
1992

33. Kinematic Analysis and Optimization of a New Three Degree-of-Freedom Spatial Parallel Manipulator

Author

Carretero, J. A., Podhorodeski, R. P., Nahon, M. A., and Gosselin, C. M.

Subjects
Manipulators -- Analysis, Machinery, Kinematics of -- Analysis, Engineering and manufacturing industries, Science and technology
Abstract

A study of the kinematic characteristics of a three degree-of-freedom (dof) parallel mechanism is presented. The architecture of the mechanism is comprised of a mobile platform attached to a base through three identical prismatic-revolute-spherical jointed serial linkages. The prismatic joints are considered to be actuated. These prismatic actuators lie on a common plane and have radial directions of action. The mechanism's inverse displacement solution is obtained. Since the mechanism has only 3 dof constraint equations describing the inter-relationship between the six motion coordinates are derived. These constraints allow the definition of parasitic motions, i.e., motions in the three unspecified motion coordinates. Architecture optimization of the device is undertaken demonstrating that specific values of design variables allow minimization of parasitic motion. [S1050-0472(00)00101-X]

Published
2000

34. New CO absorption spectroscopy data with the VUV-FTS on the DESIRS beam line at SOLEIL - Affiche

Author

Eidelsberg J.L. Lemaire S.R. Federman J.H. Fillion F. Rostas Y. Sheffer N. de Oliveira L. Nahon M. Roudjane, M., Laboratoire de Physique Moleculaire pour l'Atmosphere et l'Astrophysique (LPMAA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), and Francois, Francoise

Subjects
[PHYS.ASTR.EP] Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], [SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], [SDU.ASTR.EP] Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP]
Published
2009

35. Simulation of an underwater glider

Author

Stante, G., Nahon, M., and Williams, C. D.

Abstract

Underwater gliders are being proposed as an alternative to the resource intensive and costly shipboard methods of oceanographic data collection. One such underwater vehicle currently in operation is the SLOCUM Glider. The purpose of the present work is to devise a dynamic simulation for the SLOCUM Glider that allows the vehicle's motion to be predicted in response to control inputs. Such a simulation could be used to test operational scenarios and to aid in vehicle design. The simulation developed here relies on a component buildup method in which the hydrodynamics of the vehicle components (hull, wings, vertical fin) are estimated and summed. The simulation was validated against available experimental data. The agreement was reasonable, though it was determined that more precise information on the real vehicle was needed before further evaluations could be made. It was found that very small displacements of the vehicle C.G. had a substantial impact on the ensuing motion, and that the vehicle exhibited very stable behavior. Lateral oscillations observed in the real vehicle motion were attributed to an unmodeled interaction between the vehicle and its control system., 15th International Symposium on Unmanned Untethered Submersible Technology, 19-22 August 2007, Durham, NH

Published
2007

45. Enabling autonomous capabilities in underwater robotics

Author

Sattar, J., primary, Dudek, G., additional, Chiu, O., additional, Rekleitis, I., additional, Giguere, P., additional, Mills, A., additional, Plamondon, N., additional, Prahacs, C., additional, Girdhar, Y., additional, Nahon, M., additional, and Lobos, J.-P., additional

Published
2008
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