Automobiles - Vehicle_Dynamics(14)

FHRegensburg,UniversityofAppliedSciencesProf.Dr.-Ing.G.Rill

Theunitvectorsinthedirectionsofcircumferentialandlateralforcesexandeyaswellasthetracknormalenfollowfromthecontactgeometry.

1.4.2ToeandCamberAngle

1.4.2.1De nitionsaccordingtoDIN70000

Theanglebetweenthevehiclecenterplaneinlongitudinaldirectionandtheintersectionlineofthetirecenterplanewiththetrackplaneisnamedtoeangle.Itispositive,ifthefrontpartofthewheelisorientedtowardsthevehiclecenterplane,

Fig.1.9.

front

F

F

rear

Figure1.9:PositiveToeAngle

Thecamberangleistheanglebetweenthewheelcenterplaneandthetracknormal.Itispositive,iftheupperpartofthewheelisinclinedoutwards,Fig.1.10.

topF

F

bottom

Figure1.10:PositiveCamberAngle

1.4.2.2Calculation

Thecalculationofthetoeangleisdonefortheleftwheel.TheunitvectoreyRindirectionofthewheelrotationaxisisdescribedinthevehicle xedcoordinatesystemF,Fig.1.11

eyR,F=

(1)eyR,F(2)eyR,F(3)eyR,F

T

,(1.1)

wheretheaxisxFandzFspanthevehiclecenterplane.ThexF-axispointsforwardandthezF-axispointsupward.Thetoeangleδcanthenbecalculatedfrom

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