Compliance - Revision history

FsaeIllumina: fixed link format

2021-01-18T17:04:50Z

fixed link format

FsaeIllumina: Added See Also

2021-01-18T17:04:07Z

Added See Also

FsaeIllumina at 16:30, 11 January 2021

2021-01-11T16:30:58Z

IvoPivo: Linked to camber angle

2020-05-25T13:33:16Z

Linked to camber angle

Toaster at 23:17, 19 May 2020

2020-05-19T23:17:04Z

IvoPivo: Added link to Tube Frame

2020-05-19T13:44:20Z

Added link to Tube Frame

IvoPivo: Added to category Vehicle Dynamics

2020-05-19T13:39:24Z

Added to category Vehicle Dynamics

IvoPivo: Rudimentary page created

2020-05-19T13:35:21Z

Rudimentary page created

New page

Compliance is the inverse of stiffness. It might seem a bit backwards at first, but perhaps becomes more intuitive when you consider "compliance budgets" (mainly considered in vehicle dynamics/suspension, but occasionally applicable to other systems).

== Compliance calculation applied to suspension ==
For example, every tire has an ideal camber angle for maximum lateral force generation. However, as force is generated the suspension will strain and deform, so this angle cannot be realistically maintained. It follows then that in addition to targeting a specific angle, it is also wise to define a maximum tolerable deviation from this angle (or rather a maximum tolerable grip loss), or a maximum "compliance" in the suspension, e.g. 1° at 1G lateral. This angle can then be further divided into the various components of the suspension e.g. 0.1° in the upright, 0.05° in the bearings, 0.1° in the hub and 0.2° in the rim etc. Now we have a concrete target for the respective components to be judged against.

Naturally we generally want to minimise suspension compliance, but as with everything, this cannot be done without compromises (e.g increased weight).

== Example of compliance minimisation ==
A popular type of roast on various FS forums is pictures of suspension points mounted on a tube, away from any nodes. This violates the central rule of truss structures (two-force members only) and will result in dis-proportionate amounts of compliance as the tube bends. Reacting the suspension forces at nodes will make the assembly much stiffer at minimal cost.

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 [https://www.reddit.com/r/FSAE/comments/kr6guf/compliance_estimation/ Reddit Discussion with Bill Cobb]
-[https://www.researchgate.net/publication/289973663_Compliance_and_Friction_in_Elastic_and_Mechanical_Joints_of_Race_Car_Suspensions Zipfel
+[https://www.researchgate.net/publication/289973663_Compliance_and_Friction_in_Elastic_and_Mechanical_Joints_of_Race_Car_Suspensions Zipfel George Compliance and Friction in Elastic and Mechanical Joints of Race Car Suspensions 2006]
 [[Category:Vehicle Dynamics]]

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 == See Also ==
 [[Bearings]]
 [[Category:Vehicle Dynamics]]

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 ==Example of Compliance Minimisation==
 A popular type of roast on various FS forums is pictures of suspension points mounted on a tube, away from any nodes. This violates the central rule of truss structures (two-force members only, see [[Tube Frame]]) and will result in dis-proportionate amounts of compliance as the tube bends. Reacting the suspension forces at nodes will make the assembly much stiffer at minimal cost.
 [[Category:Vehicle Dynamics]]

@@ Line 3: / Line 3: @@
 ==Compliance Calculation Applied to Suspension==
-For example, every tire has an ideal camber angle for maximum lateral force generation. However, as force is generated the suspension will strain and deform, so this angle cannot be realistically maintained. It follows then that in addition to targeting a specific angle, it is also wise to define a maximum tolerable deviation from this angle (or rather a maximum tolerable grip loss), or a maximum "compliance" in the suspension, e.g. 1° at 1G lateral. This angle can then be further divided into the various components of the suspension e.g. 0.1° in the upright, 0.05° in the bearings, 0.1° in the hub and 0.2° in the rim etc. Now we have a concrete target for the respective components to be judged against.
+For example, every tire has an ideal [[camber angle]] for maximum lateral force generation. However, as force is generated the suspension will strain and deform, so this angle cannot be realistically maintained. It follows then that in addition to targeting a specific angle, it is also wise to define a maximum tolerable deviation from this angle (or rather a maximum tolerable grip loss), or a maximum "compliance" in the suspension, e.g. 1° at 1G lateral. This angle can then be further divided into the various components of the suspension e.g. 0.1° in the upright, 0.05° in the bearings, 0.1° in the hub and 0.2° in the rim etc. Now we have a concrete target for the respective components to be judged against.
 Naturally we generally want to minimise suspension compliance, but as with everything, this cannot be done without compromises (e.g increased weight).

@@ Line 2: / Line 2: @@
-== Compliance calculation applied to suspension ==
+==Compliance Calculation Applied to Suspension==
 For example, every tire has an ideal camber angle for maximum lateral force generation. However, as force is generated the suspension will strain and deform, so this angle cannot be realistically maintained. It follows then that in addition to targeting a specific angle, it is also wise to define a maximum tolerable deviation from this angle (or rather a maximum tolerable grip loss), or a maximum "compliance" in the suspension, e.g. 1° at 1G lateral. This angle can then be further divided into the various components of the suspension e.g. 0.1° in the upright, 0.05° in the bearings, 0.1° in the hub and 0.2° in the rim etc. Now we have a concrete target for the respective components to be judged against.
@@ Line 8: / Line 8: @@
-== Example of compliance minimisation ==
+==Example of Compliance Minimisation==
 A popular type of roast on various FS forums is pictures of suspension points mounted on a tube, away from any nodes. This violates the central rule of truss structures (two-force members only, see [[Tube Frame]]) and will result in dis-proportionate amounts of compliance as the tube bends. Reacting the suspension forces at nodes will make the assembly much stiffer at minimal cost.
 [[Category:Vehicle Dynamics]]

← Older revision		Revision as of 13:39, 19 May 2020
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	== Example of compliance minimisation ==		== Example of compliance minimisation ==
	A popular type of roast on various FS forums is pictures of suspension points mounted on a tube, away from any nodes. This violates the central rule of truss structures (two-force members only) and will result in dis-proportionate amounts of compliance as the tube bends. Reacting the suspension forces at nodes will make the assembly much stiffer at minimal cost.		A popular type of roast on various FS forums is pictures of suspension points mounted on a tube, away from any nodes. This violates the central rule of truss structures (two-force members only) and will result in dis-proportionate amounts of compliance as the tube bends. Reacting the suspension forces at nodes will make the assembly much stiffer at minimal cost.
		+
		+	[[Category:Vehicle Dynamics]]