Suspension Geometry and Kinematics - Revision history

SpookySimon: /* Track width */

2024-04-05T13:11:28Z

Track width

SpookySimon: /* Camber */

2023-06-05T19:26:32Z

Camber

SpookySimon: /* Camber */

2023-06-05T17:58:24Z

Camber

SpookySimon: /* Track width */

2023-06-05T17:38:52Z

Track width

FsaeIllumina: FsaeIllumina moved page Suspension Geometry to Suspension Geometry and Kinematics: Kinematics are closely related with geometry.

2021-01-14T17:04:55Z

FsaeIllumina moved page Suspension Geometry to Suspension Geometry and Kinematics: Kinematics are closely related with geometry.

AG: /* Kingpin */

2020-08-18T15:16:04Z

Kingpin

IvoPivo at 11:19, 26 May 2020

2020-05-26T11:19:16Z

IvoPivo at 11:02, 26 May 2020

2020-05-26T11:02:21Z

AG at 21:30, 24 May 2020

2020-05-24T21:30:44Z

AG at 21:08, 24 May 2020

2020-05-24T21:08:56Z

@@ Line 6: / Line 6: @@
 * Narrower track reduces rear wing, front wing, and undertray width, reducing aero potential
 * Narrower track tightens the racing line - can be very beneficial on a maneuverability emphasized course, such as the autocross and endurance. <!-- unclear-->
 These need to be analyzed for an adequate tradeoff.

@@ Line 21: / Line 21: @@
 ==Camber==
-Camber is the front view angle of the tire from the vertical axis. The top of the tire pointing inwards is referred to as "negative camber". As a note: positive camber is undesirable from a traction POV. Positive camber has the potential to improve drivability, as seen on 1950s F1 cars.
+[[File:Annotation 2020-05-25 001418.png|right|middle|thumb|Camber Justification ]]
-Why? Evening out the contact patch pressure, under lateral load.<!-- unclear language-->[[File:Annotation 2020-05-25 001418.png|center|middle|thumb|Camber Justification ]]
+The tire's camber will change as the suspension articulates. The tire will also see camber change due to body roll seen in a turn. This is known, unsurprisingly, as ''Camber gain''. With 0 camber gain, a vehicle that rolls 1 degree will see 1 degree of camber change in the tire.<!-- 1 degree vs one degree?--> On a double-wishbone car, there are two simple ways to achieve camber gain. The first is to make the upper a-arm shorter than the lower a-arm. The second is to place the inboard pickup points vertically closer than the outboard points are.
+<!-- need more explanation, the below is insufficient at untangling the mess, pictures may help-->
 Why would that be desirable? static camber could cause the inner part of the tire to overheat on the straights, and so even if the camber during a corner is ideal, the tire wear and tire temperature would say otherwise. So, general considerations in the solution:
@@ Line 37: / Line 36: @@
 * Account for camber deflection sources, and build in adjustabity of at least static camber.
 The "ideal" compromise of these factors has requires detailed analysis.
 ==Toe==

@@ Line 21: / Line 21: @@
 ==Camber==
-Camber is the front view angle of the tire from the vertical axis. The top of the tire pointing inwards is referred to as "negative camber". Positive camber is never desirable (from a traction POV. Positive camber can improve driveability, as seen on 1950s F1 cars).
+Camber is the front view angle of the tire from the vertical axis. The top of the tire pointing inwards is referred to as "negative camber". As a note: positive camber is undesirable from a traction POV. Positive camber has the potential to improve drivability, as seen on 1950s F1 cars.
+Why? Evening out the contact patch pressure, under lateral load.<!-- unclear language-->[[File:Annotation 2020-05-25 001418.png|center|middle|thumb|Camber Justification ]]

@@ Line 2: / Line 2: @@
 This has 4 main considerations:
 * If the track is too narrow, the car may fail the 60deg tilt test
-* Narrower track increases load transfer, reducing lateral grip
+** The minimum track width for a vehicle can be found with some trig and your vehicle's CG height
 * Narrower track reduces rear wing, front wing, and undertray width, reducing aero potential
-* Narrower track tightens the racing line - can be very beneficial on a manuverability emphasized course, such as the autoX and endurance.
+* Narrower track tightens the racing line - can be very beneficial on a maneuverability emphasized course, such as the autocross and endurance. <!-- unclear-->
 These need to be analyzed for an adequate tradeoff.
 ==Wheelbase==

@@ Line 50: / Line 50: @@
 “Nothing is rigid; 0.2mm of deflection here and 0.3mm of deflection there, and suddenly your front camber or you rear toe is far, far away from what you thought it was. From the driver input (steering wheel, brake pedal, throttle) to the tyres’ contact patch, there are dozens of non-linear springs, dampers, and hysteresis that compromise the racecar’s response to that driver input. [[Compliance]] is the biggest enemy of your driver’s Control and Confidence.”
 ==Kingpin==
 ==Caster==
 [[File:Image161.png|right|middle|thumb|Caster Offset ]]Caster is the side-view angle of the steering axis to the vertical. It affects:

← Older revision	Revision as of 17:04, 14 January 2021
(No difference)

← Older revision		Revision as of 11:19, 26 May 2020
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	==Camber==		==Camber==
−	Camber is the front view angle of the tire from the vertical axis. The top of the tire pointing inwards is referred to as "negative camber". Positive camber is never desirable.	+	Camber is the front view angle of the tire from the vertical axis. The top of the tire pointing inwards is referred to as "negative camber". Positive camber is never desirable (from a traction POV. Positive camber can improve driveability, as seen on 1950s F1 cars).

@@ Line 6: / Line 6: @@
 * Narrower track tightens the racing line - can be very beneficial on a manuverability emphasized course, such as the autoX and endurance.
 These need to be analyzed for an adequate tradeoff.
 ==Wheelbase==
 Considerations:
@@ Line 15: / Line 16: @@
 * Longer can allow more flexibilty with CG longtitudonal location
 An adequate compromise must be made.
 ==Camber==
 ==Toe==
 ==Kingpin==
 ==Caster==
 ==Roll Center==
 ==Bump Center==
@@ Line 32: / Line 57: @@
 ** A 3D "linkage sketch" - movable, with equal length relations to the "geometry sketch" - so that it can be cycled through travel, while getting geometry updates from the geometry sketch.
 It can look like this:
 [[File:Image162.png|center|middle|thumb|Movable Sketch ]]