6,252 research outputs found
Aerospace medicine and biology: A continuing bibliography with indexes (supplement 341)
This bibliography lists 133 reports, articles and other documents introduced into the NASA Scientific and Technical Information System during September 1990. Subject coverage includes: aerospace medicine and psychology, life support systems and controlled environments, safety equipment, exobiology and extraterrestrial life, and flight crew behavior and performance
How a Diverse Research Ecosystem Has Generated New Rehabilitation Technologies: Review of NIDILRR’s Rehabilitation Engineering Research Centers
Over 50 million United States citizens (1 in 6 people in the US) have a developmental, acquired, or degenerative disability. The average US citizen can expect to live 20% of his or her life with a disability. Rehabilitation technologies play a major role in improving the quality of life for people with a disability, yet widespread and highly challenging needs remain. Within the US, a major effort aimed at the creation and evaluation of rehabilitation technology has been the Rehabilitation Engineering Research Centers (RERCs) sponsored by the National Institute on Disability, Independent Living, and Rehabilitation Research. As envisioned at their conception by a panel of the National Academy of Science in 1970, these centers were intended to take a “total approach to rehabilitation”, combining medicine, engineering, and related science, to improve the quality of life of individuals with a disability. Here, we review the scope, achievements, and ongoing projects of an unbiased sample of 19 currently active or recently terminated RERCs. Specifically, for each center, we briefly explain the needs it targets, summarize key historical advances, identify emerging innovations, and consider future directions. Our assessment from this review is that the RERC program indeed involves a multidisciplinary approach, with 36 professional fields involved, although 70% of research and development staff are in engineering fields, 23% in clinical fields, and only 7% in basic science fields; significantly, 11% of the professional staff have a disability related to their research. We observe that the RERC program has substantially diversified the scope of its work since the 1970’s, addressing more types of disabilities using more technologies, and, in particular, often now focusing on information technologies. RERC work also now often views users as integrated into an interdependent society through technologies that both people with and without disabilities co-use (such as the internet, wireless communication, and architecture). In addition, RERC research has evolved to view users as able at improving outcomes through learning, exercise, and plasticity (rather than being static), which can be optimally timed. We provide examples of rehabilitation technology innovation produced by the RERCs that illustrate this increasingly diversifying scope and evolving perspective. We conclude by discussing growth opportunities and possible future directions of the RERC program
Magneto-Rheological Actuators for Human-Safe Robots: Modeling, Control, and Implementation
In recent years, research on physical human-robot interaction has received considerable attention. Research on this subject has led to the study of new control and actuation mechanisms for robots in order to achieve intrinsic safety. Naturally, intrinsic safety is only achievable in kinematic structures that exhibit low output impedance. Existing solutions for reducing impedance are commonly obtained at the expense of reduced performance, or significant increase in mechanical complexity. Achieving high performance while guaranteeing safety seems to be a challenging goal that necessitates new actuation technologies in future generations of human-safe robots.
In this study, a novel two degrees-of-freedom safe manipulator is presented. The manipulator uses magneto-rheological fluid-based actuators. Magneto-rheological actuators offer low inertia-to-torque and mass-to-torque ratios which support their applications in human-friendly actuation. As a key element in the design of the manipulator, bi-directional actuation is attained by antagonistically coupling MR actuators at the joints. Antagonistically coupled MR actuators at the joints allow using a single motor to drive multiple joints. The motor is located at the base of the manipulator in order to further reduce the overall weight of the robot. Due to the unique characteristic of MR actuators, intrinsically safe actuation is achieved without compromising high quality actuation. Despite these advantages, modeling and control of MR actuators present some challenges. The antagonistic configuration of MR actuators may result in limit cycles in some cases when the actuator operates in the position control loop. To study the possibility of limit cycles, describing function method is employed to obtain the conditions under which limit cycles may occur in the operation of the system. Moreover, a connection between the amplitude and the frequency of the potential limit cycles and the system parameters is established to provide an insight into the design of the actuator as well as the controller. MR actuators require magnetic fields to control their output torques. The application of magnetic field however introduces hysteresis in the behaviors of MR actuators. To this effect, an adaptive model is developed to estimate the hysteretic behavior of the actuator. The effectiveness of the model is evaluated by comparing its results with those obtained using the Preisach model. These results are then extended to an adaptive control scheme in order to compensate for the effect of hysteresis. In both modeling and control, stability of proposed schemes are evaluated using Lyapunov method, and the effectiveness of the proposed methods are validated with experimental results
Recommended from our members
Bradford Non-Lethal Weapons Research Project (BNLWRP). Research Report No. 7.
yesThe length of this Bradford Non-Lethal Weapons Research Project Report No.7 again reflects
the interest related to non-lethal weapons from academics, research institutes, policy makers,
the police and the military.
A number of reports, particularly concerning the Taser electro-shock weapon, have been
published from these sectors since our last BNLWRP Report No.6 in October 2004. Some,
such as the Amnesty International (U.S. and Canada) have again raised, and stressed, the
concerns about the safety of the weapon and the number of deaths associated with its use.
Others, such as the Joint Non-Lethal Weapons Human Effects Center of Excellence
(HECOE), Human Effectiveness and Risk Characterization of the Electromuscular
Incapacitation Device Âż A Limited Analysis of the TASER. (March 2005) concluded that the
Taser was relatively safe, but that further research was needed into potential bio-effects, and
for continual development into a safer weapon. Reaction to these reports was mixed. Some
US legislators called for limitations on the use of Tasers, more accountability, and the
detailed recording of incidents in which they were used.1 Others called for a ban on their use
until more testing was carried out regarding their potentially harmful effects. A number of US
police forces stopped the use of Taser, slowed down the deployment and ordering of the
weapons, reviewed their rules of engagement and reporting, and revisited their operational
guidelines. The International Association of Chiefs of Police (IACP) published the Electro-
Muscular Disruption Technology (EMDT). A Nine-Step Strategy For Effective Deployment.
(April 2005) as a response to these growing concerns. Certain elements of the media,
especially The Arizona Republic2 and others, took a hostile view of what they considered the
scandal of the number of deaths and associated serious injuries caused by the Taser. Taser
International challenged allegations that their weapon was directly responsible for these
deaths and quoted reports, such as the Madison Police Department report (February 2005),
the study by McDaniel, W & Stratbucker, R & Nerheim, M & Brewer, J. Cardiac Safety of
Neuromuscular Incapacitating Defensive Devices (January 2005), and the U.K. DOMILL
Statement (March 2005) to support their view. The controversy continues.
Other than Tasers, there are still few reports of the newer non-lethal technologies actually
being deployed in operations. The exception to this is the Long Range Acoustic Device
(LRAD), which is now in widespread use in Iraq. Little additional information has appeared
regarding the `active denialÂż weapon we have described in previous reports
Aerospace medicine and biology: A continuing bibliography with indexes (supplement 308)
This bibliography lists 175 reports, articles, and other documents introduced into the NASA scientific and technical information system in February, 1988
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