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Automatic merge of T1.5.1-664-gd39447273 and 8 pull requests
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- Pull request #839 at d00beb9: First phase of https://blueprints.launchpad.net/or/+spec/additional-cruise-control-parameters
- Pull request #865 at 776d6df: Dispatcher window improvements
- Pull request #874 at f8dbeab: Dynamic brake controller refactoring
- Pull request #875 at 43bf33e: Bug fix for https://bugs.launchpad.net/or/+bug/2036346 Player train switching doesn't work with 3D cabs
- Pull request #876 at f92de76: docs: add source for documents previously on website to source Documentation folder
- Pull request #878 at ef944ab: Implement Polach Adhesion
- Pull request #879 at 5a0ff7b: chore: remove Website folder
- Pull request #880 at 084b404: fix: Refined comment summarising property SData1
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openrails-bot committed Oct 14, 2023
10 parents fe18d65 + d394472 + d00beb9 + 776d6df + f8dbeab + 43bf33e + f92de76 + ef944ab + 5a0ff7b + 084b404 commit 03ad6ce
Showing 1 changed file with 33 additions and 16 deletions.
49 changes: 33 additions & 16 deletions Source/Orts.Simulation/Simulation/RollingStocks/SubSystems/PowerTransmissions/Axle.cs
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Expand Up @@ -587,17 +587,24 @@ public void ComputeWheelSlipThresholdMpS()
double fa = SlipCharacteristics(a + dx) - SlipCharacteristics(a);
double fb = SlipCharacteristics(b + dx) - SlipCharacteristics(b);

double p = 0.025f;
double s = 0.05f;
double t = 0.1f;
double q = 0.15f;
double r = 0.2f;
double u = 0.25f;
double v = 0.5f;
double x = 0.75f;
double y = 1.0f;

double fa1 = SlipCharacteristics(a);
double fb1 = SlipCharacteristics(b);

double fp = SlipCharacteristics(p);
double fs = SlipCharacteristics(s);
double ft = SlipCharacteristics(t);
double fq = SlipCharacteristics(q);
double fr = SlipCharacteristics(r);
double fu = SlipCharacteristics(u);
double fv = SlipCharacteristics(v);
double fx = SlipCharacteristics(x);
Expand All @@ -617,10 +624,10 @@ public void ComputeWheelSlipThresholdMpS()
if (fa * fb > 0)
{
// If sign does not change, bisection fails
WheelSlipThresholdMpS = MpS.FromKpH(0.05f);
WheelSlipThresholdMpS = MpS.FromKpH(0.1f);
return;
}
while (Math.Abs(b - a) > MpS.FromKpH(0.05f))
while (Math.Abs(b - a) > MpS.FromKpH(0.1f))
{
double c = (a + b) / 2;
double fc = SlipCharacteristics(c + dx) - SlipCharacteristics(c);
Expand All @@ -635,10 +642,10 @@ public void ComputeWheelSlipThresholdMpS()
fb = fc;
}
}
WheelSlipThresholdMpS = (float)Math.Max((a + b) / 2, MpS.FromKpH(0.05f));
WheelSlipThresholdMpS = (float)Math.Max((a + b) / 2, MpS.FromKpH(0.1f));

// if (SlipSpeedMpS > 0)
// Trace.TraceInformation("Fx Values - a {0} fa1 {1} b {2} fb1 {3} s {4} fs {5} t {6} ft {7} u {8} fu {9} v {10} fv {11} x {12} fx {13} y {14} fy {15} Speed {16} Threshold {17} Fslip {18} SlipSpeed {19}", a, fa1, b, fb1, s, fs, t, ft, u, fu, v, fv, x, fx, y, fy, TrainSpeedMpS, WheelSlipThresholdMpS, fslip, SlipSpeedMpS);
// if (SlipSpeedMpS > 0)
// Trace.TraceInformation("Fx Values - a {0} fa1 {1} b {2} fb1 {3} s {4} fs {5} t {6} ft {7} u {8} fu {9} v {10} fv {11} x {12} fx {13} y {14} fy {15} Speed {16} Threshold {17} Fslip {18} SlipSpeed {19}", a, fa1, b, fb1, s, fs, t, ft, u, fu, v, fv, x, fx, y, fy, TrainSpeedMpS, WheelSlipThresholdMpS, fslip, SlipSpeedMpS);

}

Expand All @@ -659,7 +666,7 @@ public float SlipSpeedMpS
{
get
{
return (float)(AxleSpeedMpS - TrainSpeedMpS);
return Math.Abs((float)(AxleSpeedMpS - TrainSpeedMpS));
}
}

Expand Down Expand Up @@ -976,7 +983,7 @@ public virtual void Update(float timeSpan)
if (Math.Abs(SlipSpeedMpS) > WheelSlipThresholdMpS)
{
// Wait some time before indicating wheelslip to avoid false triggers
if (WheelSlipTimeS > 0.1f)
if (WheelSlipTimeS > 0.75f)
{
IsWheelSlip = IsWheelSlipWarning = true;
}
Expand All @@ -985,7 +992,7 @@ public virtual void Update(float timeSpan)
else if (Math.Abs(SlipSpeedPercent) > SlipWarningTresholdPercent)
{
// Wait some time before indicating wheelslip to avoid false triggers
if (WheelSlipWarningTimeS > 0.1f) IsWheelSlipWarning = true;
if (WheelSlipWarningTimeS > 0.75f) IsWheelSlipWarning = true;
IsWheelSlip = false;
WheelSlipWarningTimeS += timeSpan;
}
Expand Down Expand Up @@ -1048,6 +1055,7 @@ public void Update()
// Calculate Hertzian values - assume 2b = 12mm.
var b_HertzianMM = 6.0;
a_HertzianMM = (3.04f / 2) * Math.Sqrt(((wheelLoadkN * wheelRadiusMM * 1000) / (2 * b_HertzianMM * Young_ModulusMPa)));
var a_HertzianM = a_HertzianMM / 1000;

var hertzianMM = a_HertzianMM / b_HertzianMM;
var hertzianMM2 = hertzianMM * hertzianMM;
Expand All @@ -1059,27 +1067,30 @@ public void Update()

// Calculate slip and creep values
var wheelProfileConicityRad = 0.5f;
var wheelContactAngleRad = MathHelper.ToRadians(60);
var wheelContactAngleRad = MathHelper.ToRadians(3); // Assume that on straight track wheel runs on the tread which has a 1 in 20 slope = 3 deg
// At a later date this could be changed when in a curve to run on the flange at a steeper angle.
var wheelCentreDeviationMM = 3.0f;

spinM1 = Math.Sin(wheelContactAngleRad) / Axle.WheelRadiusM; // set spin assuming wheel running on tread

double YawAngleRad = 0;
if (Axle.CurrentCurveRadiusM > 0)
{
YawAngleRad = Math.Asin(2.0f * Axle.BogieRigidWheelBaseM / Axle.CurrentCurveRadiusM);
spinM1 = Math.Sin(Axle.WheelFlangeAngleRad) / Axle.WheelRadiusM; // Overwrite spin if locomotive is on a curve. Assume wheel running on flange
}

if (float.IsNaN((float)spinM1)) spinM1 = 0;//avoid NaN when first starting OR

var supplenessFactor = (wheelDistanceGaugeMM * wheelRadiusMM) / (wheelProfileConicityRad * wheelCentreDeviationMM);
var lateralSlipVelocityMpS = Math.Abs(((-1 * Axle.CurrentCurveRadiusM * YawAngleRad) / supplenessFactor) * trainSpeedMpS);
Sy = lateralSlipVelocityMpS / trainSpeedMpS;
if (float.IsNaN((float)Sy)) Sy = 0;//avoid NaN when first starting OR
Sy2 = Sy * Sy;

spinM1 = Math.Sin(Axle.WheelFlangeAngleRad) / wheelRadiusMM;

// Trace.TraceInformation("Spin - {0} FlangeAngle {1} wheelRadius {2} Speed {3}", spinM1, Axle.WheelFlangeAngleRad, wheelRadiusMM, trainSpeedMpS);

if (float.IsNaN((float)spinM1)) spinM1 = 0;//avoid NaN when first starting OR

Syc = Sy + (spinM1 * a_HertzianMM);
Syc = Sy + (spinM1 * a_HertzianM);
Syc2 = Syc * Syc;

// Trace.TraceInformation("Sy - {0} Syc {1} Spin {2} a_hertz {3}", Sy, Syc, spinM1, a_HertzianMM);
Expand All @@ -1100,6 +1111,8 @@ public double SlipCharacteristics(double slipSpeedMpS)
{
var polach_uadhesion = zeroSpeedAdhesion * (((1 - polach_A) * Math.Exp(-polach_B * slipSpeedMpS)) + polach_A);

// Trace.TraceInformation("Polach Adhesion - {0} ZeroAdhesion {1} RawPolach {2} SlipSpeed {3}", polach_uadhesion, zeroSpeedAdhesion, (((1 - polach_A) * Math.Exp(-polach_B * slipSpeedMpS)) + polach_A), slipSpeedMpS);

if (trainSpeedMpS < 0.05f)
return polach_uadhesion;

Expand Down Expand Up @@ -1127,16 +1140,20 @@ public double SlipCharacteristics(double slipSpeedMpS)

var fx = (f * Sx / Sc) / wheelLoadN;

// if (fx < 0)
/*
// if (slipSpeedMpS == 0.025f || slipSpeedMpS == 0.05f || slipSpeedMpS == 0.1f || slipSpeedMpS == 0.15f || slipSpeedMpS == 0.2f)
if (Axle.IsWheelSlip)
{
// Trace.TraceInformation("Negative Fx - Fx {0} Speed {1} SlipSpeed {2} Sx {3} PolachAdhesion {4} adhesionComponent {5} slipComponent {6} Polach_Ks {7} Stiffness2 {8} SlipForce {9} Sc {10} WheelLoad {11} Syc {12} Hertz_a {13}", fx, (float)trainSpeedMpS, (float)slipSpeedMpS, (float)Sx, polach_uadhesion, adhesionComponent, slipComponent, polach_Ks, Stiffness2, f, Sc, wheelLoadN, Syc, a_HertzianMM);
Trace.TraceInformation("Negative Fx - Fx {0} Speed {1} SlipSpeed {2} Sx {3} PolachAdhesion {4} adhesionComponent {5} slipComponent {6} Polach_Ks {7} Stiffness2 {8} SlipForce {9} Sc {10} WheelLoad {11} Syc {12} Hertz_a {13} Sy {14} Threshold {15}", fx, (float)trainSpeedMpS, (float)slipSpeedMpS, (float)Sx, polach_uadhesion, adhesionComponent, slipComponent, polach_Ks, Stiffness2, f, Sc, wheelLoadN, Syc, a_HertzianMM, Sy, Axle.WheelSlipThresholdMpS);
}
*/

return fx;
}
}


/// <summary>
/// Uses the Polach creep force curves calculation described in the following document
/// "Creep forces in simulations of traction vehicles running on adhesion limit" by O. Polach 2005 Wear - http://www.sze.hu/~szenasy/VILLVONT/polachslipvizsg.pdf
Expand Down

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