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{{Short description|Kinematic pair which constrains bodies to pure rotation about a common axis}}
[[File:Revolute joint.svg|200px|thumb|right|Revolute joint seen in 3-dimensional, noting that the joint may only move in one direction.]]
{{multiple image
A '''revolute joint''' (also called '''pin joint''' or '''hinge joint''') is a one-[[Degrees of freedom (mechanics)|degree-of-freedom]] [[kinematic pair]] used in mechanisms.<ref name="norton">{{cite book|last=Norton|first=Robert L.|title=Design of Machinery|publisher=McGraw Hill Higher Education|location=Boston, MA|date=2008|edition=4th|pages=33|chapter=2|isbn=978-0-07-312158-1|language=English (American)}}</ref> Revolute joints provide single-axis rotation function used in many places such as door hinges, folding mechanisms, and other uni-axial rotation devices. <ref name="uta">{{cite web|url=http://www.robotics.utexas.edu/rrg/learn_more/low_ed/joints/|title=Joint Types|last=Robotics Research Group|publisher=University of Texas at Austin|language=English (American)|accessdate=2009-02-04}}</ref>
| width = 150
| image1 = Revolute_Pin_Joint.png
| alt1 = Revolute joint with shoulders cutaway view
| image2 = Revolute joint.svg
| alt2 = Revolute joint cutaway view
| footer = Revolute joint with and without shoulders, cutaway views
}}

A '''revolute joint''' (also called '''pin joint''' or '''hinge joint''') is a one-[[Degrees of freedom (mechanics)|degree-of-freedom]] [[kinematic pair]] used frequently in [[Mechanism (engineering)|mechanism]]s and [[machine]]s.<ref name="norton">{{cite book|last=Norton|first=Robert L.|title=Design of Machinery|publisher=McGraw Hill Higher Education|location=Boston, MA|date=2008|edition=4th|pages=33|chapter=2|isbn=978-0-07-312158-1}}</ref> The joint [[Constraint (classical mechanics)|constrains]] the motion of two bodies to pure rotation along a common [[Rotation around a fixed axis|axis]]. The joint does not allow [[Sliding (motion)|translation]], or sliding [[linear motion]], a constraint not shown in the diagram. Almost all assemblies of multiple moving bodies include revolute joints in their designs. Revolute joints are used in numerous applications such as door [[hinge]]s, mechanisms, and other uni-axial rotation devices.<ref name="uta">{{cite web |url=http://www.robotics.utexas.edu/rrg/learn_more/low_ed/joints/ |title=Joint Types |last=Robotics Research Group |publisher=University of Texas at Austin |access-date=2009-02-04 |url-status=dead |archive-url=https://web.archive.org/web/20090311072110/http://www.robotics.utexas.edu/rrg/learn_more/low_ed/joints/ |archive-date=2009-03-11}}</ref>

A revolute joint is usually made by a [[pin]] or [[knuckle joint]], through a rotary [[Bearing (mechanical)|bearing]]. It enforces a cylindrical contact area, which makes it a [[Kinematic pair#Lower_pair|lower kinematic pair]], also called a full joint. However, If there is any [[Engineering tolerance|clearance]] between the pin and hole (as there must be for motion), so-called surface contact in the pin joint actually becomes line contact.<ref>Norton, Robert L. ''Design of machinery: an introduction to the synthesis and analysis of mechanisms and machines''. Boston: McGraw-Hill Higher Education, 2004. p. 31.</ref>

The contact between the inner and outer cylindrical surfaces is usually assumed to be [[friction]]less. But some use simplified models assume linear [[viscous damping]] in the form <math>T=B\,\omega</math>, where {{mvar|T}} is the [[friction torque]], {{mvar|ω}} is the relative [[angular velocity]], and {{mvar|B}} is the friction constant. Some more complex models take stiction and stribeck effect into consideration.<ref>{{Cite web |last=Moore |first=Jacobs |title=Bearing Friction |url=http://mechanicsmap.psu.edu/websites/6_friction/bearing_friction/bearingfriction.html |access-date=June 6, 2020 |website=Mechanics Map}}</ref>
[[File:Revolute joint in door handle IMG 2258c.jpg|thumb|{{center|The door handle rotates an internal '''revolute joint''' to retract or release the latch bolt of the spring latch}}]]


==See also==
==See also==
{{div col|colwidth=23em}}
* [[Cylindrical joint]]
* [[Cylindrical joint]]
* [[Kinematics]]
* [[Kinematics]]
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* [[Kinematic pair]]
* [[Kinematic pair]]
* [[Mechanical joint]]
* [[Mechanical joint]]
* [[Prismatic Joint]]
* [[Prismatic joint]]
{{div col end}}


== References ==
== References ==
{{reflist}}
{{reflist}}


{{KinematicPair}}
{{Kinematic pair}}


[[Category:Kinematics]]
[[Category:Kinematics]]
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{{classicalmechanics-stub}}
{{classicalmechanics-stub}}

[[ca:Articulació (mecànica)]]
[[es:Articulación mecánica]]

Latest revision as of 11:41, 5 July 2024

Revolute joint with shoulders cutaway view
Revolute joint cutaway view
Revolute joint with and without shoulders, cutaway views

A revolute joint (also called pin joint or hinge joint) is a one-degree-of-freedom kinematic pair used frequently in mechanisms and machines.[1] The joint constrains the motion of two bodies to pure rotation along a common axis. The joint does not allow translation, or sliding linear motion, a constraint not shown in the diagram. Almost all assemblies of multiple moving bodies include revolute joints in their designs. Revolute joints are used in numerous applications such as door hinges, mechanisms, and other uni-axial rotation devices.[2]

A revolute joint is usually made by a pin or knuckle joint, through a rotary bearing. It enforces a cylindrical contact area, which makes it a lower kinematic pair, also called a full joint. However, If there is any clearance between the pin and hole (as there must be for motion), so-called surface contact in the pin joint actually becomes line contact.[3]

The contact between the inner and outer cylindrical surfaces is usually assumed to be frictionless. But some use simplified models assume linear viscous damping in the form , where T is the friction torque, ω is the relative angular velocity, and B is the friction constant. Some more complex models take stiction and stribeck effect into consideration.[4]

The door handle rotates an internal revolute joint to retract or release the latch bolt of the spring latch

See also

[edit]

References

[edit]
  1. ^ Norton, Robert L. (2008). "2". Design of Machinery (4th ed.). Boston, MA: McGraw Hill Higher Education. p. 33. ISBN 978-0-07-312158-1.
  2. ^ Robotics Research Group. "Joint Types". University of Texas at Austin. Archived from the original on 2009-03-11. Retrieved 2009-02-04.
  3. ^ Norton, Robert L. Design of machinery: an introduction to the synthesis and analysis of mechanisms and machines. Boston: McGraw-Hill Higher Education, 2004. p. 31.
  4. ^ Moore, Jacobs. "Bearing Friction". Mechanics Map. Retrieved June 6, 2020.