![Field control tower P1220950](https://upload.wikimedia.org/wikipedia/commons/5/51/Field_control_tower_P1220950.jpg)
A deployable structure is a structure that can change shape so as to significantly change its size.
Examples of deployable structures are
umbrella
An umbrella or parasol is a folding canopy supported by wooden or metal ribs that is usually mounted on a wooden, metal, or plastic pole. It is designed to protect a person against rain or sunlight. The term ''umbrella'' is traditionally used ...
s, some
tensegrity
Tensegrity, tensional integrity or floating compression is a structural principle based on a system of isolated components under compression inside a network of continuous tension, and arranged in such a way that the compressed members (usually ...
structures,
bistable structure In mechanical engineering, a bistable structure is one that has two stable mechanical shapes, particularly where they are stabilized by different curvature axes.
A common example of a bistable structure is a slap bracelet
A slap bracelet (or sn ...
s, some
Origami
) is the Japanese paper art, art of paper folding. In modern usage, the word "origami" is often used as an inclusive term for all folding practices, regardless of their culture of origin. The goal is to transform a flat square sheet of pape ...
shapes and scissor-like structures. Deployable structures are also used on spacecraft for deploying
solar panel
A solar cell panel, solar electric panel, photo-voltaic (PV) module, PV panel or solar panel is an assembly of photovoltaic solar cells mounted in a (usually rectangular) frame, and a neatly organised collection of PV panels is called a photo ...
s and
solar sail
Solar sails (also known as light sails and photon sails) are a method of spacecraft propulsion using radiation pressure exerted by sunlight on large mirrors. A number of spaceflight missions to test solar propulsion and navigation have been p ...
s.
Space-based deployable structures can be categorized into three primary classes: the first is the articulated structure class wherein rigid members contain sliding contact joints or are folded at hinge points and pivot to deploy, often locking into place. The second class consists of on-orbit assembly where a device is fabricated and/or mechanically joined in space to form the structure. The final class is high strain structures (often composed of
High strain composites) wherein the device is dramatically flexed from one configuration to another during deployment.
Gallery
File:Scissor Tower.gif, Scissor-type structure
File:Scissor Tower3.gif, Multiple scissor-type structure
File:Hoberman Mechanism.gif, Simple Hoberman mechanism
A Hoberman mechanism, or Hoberman linkage, is a deployable mechanism that turns linear motion into radial motion.
The Hoberman mechanism is made of two angulated ridged bars connected at a central point by a revolute joint, making it move much lik ...
File:Radially Fording Structure.gif, Compound Hoberman mechanism
A Hoberman mechanism, or Hoberman linkage, is a deployable mechanism that turns linear motion into radial motion.
The Hoberman mechanism is made of two angulated ridged bars connected at a central point by a revolute joint, making it move much lik ...
File:Deployable Structure1.gif, Outward folding deployable ring structure
File:Deployable Structure2.gif, Inward folding deployable ring structure
File:Nustar mast deployed v2.jpg, NuSTAR
NuSTAR (Nuclear Spectroscopic Telescope Array, also named Explorer 93 and SMEX-11) is a NASA space-based X-ray telescope that uses a conical approximation to a Wolter telescope to focus high energy X-rays from astrophysical sources, especiall ...
mast in the stowed configuration.
File:Nustar mast deployed.jpg, NuSTAR
NuSTAR (Nuclear Spectroscopic Telescope Array, also named Explorer 93 and SMEX-11) is a NASA space-based X-ray telescope that uses a conical approximation to a Wolter telescope to focus high energy X-rays from astrophysical sources, especiall ...
mast deployed.
See also
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Engineering mechanics
Applied mechanics is the branch of science concerned with the motion of any substance that can be experienced or perceived by humans without the help of instruments. In short, when mechanics concepts surpass being theoretical and are applied and e ...
*
Four-bar linkage
In the study of mechanisms, a four-bar linkage, also called a four-bar, is the simplest closed- chain movable linkage. It consists of four bodies, called ''bars'' or ''links'', connected in a loop by four joints. Generally, the joints are configu ...
*
Kinematics
Kinematics is a subfield of physics, developed in classical mechanics, that describes the Motion (physics), motion of points, Physical object, bodies (objects), and systems of bodies (groups of objects) without considering the forces that cause ...
*
Linkage (mechanical)
A mechanical linkage is an assembly of systems connected to manage forces and movement. The movement of a body, or link, is studied using geometry so the link is considered to be rigid. The connections between links are modeled as providing i ...
*
Machine
A machine is a physical system using Power (physics), power to apply Force, forces and control Motion, movement to perform an action. The term is commonly applied to artificial devices, such as those employing engines or motors, but also to na ...
*
Outline of machines
Machine – mechanical system that provides the useful application of power to achieve movement. A machine consists of a power source, or engine, and a mechanism or transmission for the controlled use of this power. The combination of fo ...
*
Overconstrained mechanism
In mechanical engineering, an overconstrained mechanism is a linkage that has more degrees of freedom than is predicted by the mobility formula. The mobility formula evaluates the degree of freedom of a system of rigid bodies that results when ...
*
Parallel motion
In kinematics, the parallel motion linkage is a six-bar mechanical linkage invented by the Scottish engineer James Watt in 1784 for the double-acting Watt steam engine. It allows a rod moving practically straight up and down to transmit moti ...
*
Slider-crank linkage
A slider-crank linkage is a four-link mechanism with three revolute joints and one prismatic, or sliding, joint. The rotation of the crank drives the linear movement the slider, or the expansion of gases against a sliding piston in a cylinder ...
*
Compliant mechanism
In mechanical engineering, a compliant mechanism is a flexible mechanism that achieves force and motion transmission through elastic body deformation. It gains some or all of its motion from the relative flexibility of its members rather than fro ...
References
External links
*{{Commonscatinline
University of Cambridge Deployable structures department publications
Linkages (mechanical)
Structural engineering