Tether

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A tether is a cord, fixture, or flexible attachment that characteristically anchors something movable to something fixed; it also may be used to connect two movable objects, such as an item being towed by its tow.

Contents

Applications for tethers include: fall arrest systems, lanyards, balloons, kites, airborne wind-power systems, anchors, floating water power systems, towing, animal constraint, space walks, power kiteing, and anti-theft devices. [1]

Failure

Failure modes for tethers are considered in their design. [2] A cord or rope tether may reach its breaking strength and fail. Outcomes can include an injury or fatal fall, and damage or loss of life to personnel or bystanders caused by backlash of the ruptured segments.

Failure-prevention may be designed into a tethering system. Some safety harnesses are used in combination with a shock-absorbing lanyard, which has break-away stitching designed into it to prevent material failure and regulate deceleration, thereby preventing a serious G-force injury to the user when the end of the rope is reached.

Designed-to-fail safety links are sometimes used to prevent excessive tension in a tether involved in towing objects, such as sailplanes.

A signal tether is a system in which a constant signal designates a positive condition, and its interruption, whether by discontinuation or jamming, conveys a failure. The signal may be electrically generated, or a physical device such as flying a flag.

See also

Related Research Articles

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<span class="mw-page-title-main">Speargun</span> Underwater fishing implement

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<span class="mw-page-title-main">Lanyard</span> Necklace used to hold ID cards or other items

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<span class="mw-page-title-main">Kill switch</span> Safety mechanism to quickly shut down a system

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<span class="mw-page-title-main">Safety harness</span> Equipment designed to protect from falling

A safety harness is a form of protective equipment designed to safeguard the user from injury or death from falling. The core item of a fall arrest system, the harness is usually fabricated from rope, braided wire cable, or synthetic webbing. It is attached securely to a stationary object directly by a locking device or indirectly via a rope, cable, or webbing and one or more locking devices. Some safety harnesses are used in combination with a shock-absorbing lanyard, which is used to regulate deceleration and thereby prevent a serious G-force injury when the end of the rope is reached.

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<span class="mw-page-title-main">Fall arrest</span> Equipment which safely stops a person already falling

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<span class="mw-page-title-main">Kite line</span>

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<span class="mw-page-title-main">Fall protection</span> Controls for workplace fall hazards

Fall protection is the use of controls designed to protect personnel from falling or in the event they do fall, to stop them without causing severe injury. Typically, fall protection is implemented when working at height, but may be relevant when working near any edge, such as near a pit or hole, or performing work on a steep surface. Many of these incidents are preventable when proper precautions are taken, making fall protection training not only critical, but also required for all construction workers. Fall Protection for Construction identifies common hazards and explains important safety practices to help ensure every team member is prepared to recognize fall hazards on the job and understand how to keep themselves and others safe.

<span class="mw-page-title-main">Crosswind kite power</span> Form of wind-powered mechanical or electrical generation

Crosswind kite power is power derived from airborne wind-energy conversion systems or crosswind kite power systems (CWKPS). The kite system is characterized by energy-harvesting parts flying transverse to the direction of the ambient wind, i.e., to crosswind mode; sometimes the entire wing set and tether set is flown in crosswind mode. From toy to power-grid-feeding sizes, these systems may be used as high-altitude wind power (HAWP) devices or low-altitude wind power (LAWP) devices without having to use towers. Flexible wings or rigid wings may be used in the kite system. A tethered wing, flying in crosswind at many times wind speed, harvests wind power from an area that exceeds the wing's total area by many times.

References

  1. Bosworth, Seymour; Kabay, M. E., eds. (2002). Computer Security Handbook. New York, NY: Wiley. p. 19. ISBN   978-0-471-41258-8.
  2. Bekey, Ivan (2003). Advanced Space System Concepts and Technologies, 2010-2030+. El Segundo, Calif. : Reston, Va.: Aerospace Press; American Institute of Aeronautics and Astronautics. p. 33. ISBN   978-1-884989-12-4.