(2)"”r"line clusterDefinition:“r" describes the relationship between front and rearbrakeforcesgivenbytheground (Fxbi~Fxb2)whenrearlockupoccurs first.Howtoget“r"?Step:I) To get the relationship between Fxbr and Fxb2>becauserearlockupoccursfirstFxb2 = Fp2 = Fz20(Ga-Gzhg)Fxb2P(Ga -Fxo1- hg -Fxo2 hg)F1Xb21-phGapthe relationship betweengF= Fxb2 +XblFxbi and FL+phgL+ph.Xb2160
Definition: “r” describes the relationship between front and rear brake forces given by the ground (FXb1~FXb2) when rear lockup occurs first. How to get “r” ? Step: 1) To get the relationship between FXb1 and FXb2 because rear lockup occurs first （2）”r” line cluster the relationship between FXb1 and FXb2 2 2 2 2 2 1 2 2 1 ( ) ( ) Xb Z Xb g Xb Xb g Xb g g Xb Xb g g F F F F Ga Gzh L F Ga F h F h L h Ga F F L h L h 16
2)ToPlot the relationship on a graphF xb20.50.5@= 0.1 0.20.30.4san ...,,0N7C2FxblGa,0)elusterso1F=0GaxblFGbxblh(1)(2)Gap(0, gFhxb2gL+ph0F二xb2817
FXb1 FXb2 g (0, ) Gb h 0 . 1 g ( ,0) Ga h “r” clusters 0 . 1 0.2 0.3 0.4 0.5 0.2 0.3 0.4 0.5 ”f” clusters 2)To Plot the relationship on a graph 1 1 2 2 0 (1) (2) 0 xb xb g xb g xb F Ga F Ga h F L h F 17
(3) To combine“f"graph with“r"graphFμ2“T""curveFXb20.50.5@=0.10.20.30.4suain..d,07C2FulFxblGa,0)elusters> Connecting the cross point of"rGband"f"with the same“o”together(0, -makestheideal proportioninghcurve"I"curve.18
FXb1 FXb2 g (0, ) Gb h 0 . 1 g ( ,0) Ga h “r” clusters “I” curve 0 . 1 0.2 0.3 0.4 0.5 0.2 0.3 0.4 0.5 ”f” clusters （3）To combine “f” graph with “r” graph Connecting the cross point of “ r ” and “f” with the same “ φ ” together makes the ideal proportioning curve ”I” curve. Fμ2 Fμ1 18
Conclusion1.There are two means to get "j" curve(1) by the relationship between Fμμand Fμ2Fu+Fu2=GpFu1 b+phgFu2a-phg(2)by the relationship between FXbl and FXb2"f" and“r"→cross points "I" curveUsually the first is the preferred one to get“I"curveFxb1 = 0GaFxblh(1)Gap(2)gFxb2L+phgH=0xb219
1.There are two means to get “I” curve (1) by the relationship between Fμ1and Fμ2 (2)by the relationship between FXb1 and FXb2 “f” and “ r ” →cross points →”I” curve Usually the first is the preferred one to get “I” curve. 1 1 2 2 0 (1) (2) 0 xb xb g xb g xb F Ga F Ga h F L h F 1 2 1 2 g g F F G F b h F a h Conclusion 19
2.KeyDefinitions"I"curve: The idea brake forces proportioning curve inthe sense of front and rear lockup occur together."β"line: The real brake forces proportioning line in thesense of the forces applied on the wheels"po":The friction coefficient of the cross point between“l"lineand“β"line.“"f"line.“f"line describes the relationship between frontand rear brake forces given by the ground (Fxb2-Fxb)whenfront lockup occursfirst."r"line:“r"line describes the relationship between frontand rear brake forces given by the ground (Fxb2-Fxb)whenrearlockup occursfirst.20
” I ” curve: The idea brake forces proportioning curve in the sense of front and rear lockup occur together. “β” line: The real brake forces proportioning line in the sense of the forces applied on the wheels. “φ0” :The friction coefficient of the cross point between “I” line and “β” line. “f” line: “f” line describes the relationship between front and rear brake forces given by the ground (FXb2~FXb1) when front lockup occurs first. “r” line: “ r ” line describes the relationship between front and rear brake forces given by the ground (FXb2~FXb1) when rear lockup occurs first. 2. Key Definitions 20