/// <summary>
/// Main Update method
/// - computes slip characteristics to get new axle force
/// - computes axle dynamic model according to its driveType
/// - computes wheelslip indicators
/// </summary>
/// <param name="timeSpan"></param>
public virtual void Update(float timeSpan)
{
//Update axle force ( = k * loadTorqueNm)
axleForceN = AxleWeightN * SlipCharacteristics(AxleSpeedMpS - TrainSpeedMpS, TrainSpeedMpS, AdhesionK, AdhesionConditions, Adhesion2);
// The Axle module subtracts brake force from the motive force for calculation purposes. However brake force is already taken into account in the braking module.
// And thus there is a duplication of the braking effect in OR. To compensate for this, after the slip characteristics have been calculated, the output of the axle module
// has the brake force "added" back in to give the appropriate motive force output for the locomotive. Braking force is handled separately.
// Hence CompensatedAxleForce is the actual output force on the axle.
var compensateAxleForceN = axleForceN;
switch (driveType)
{
case AxleDriveType.NotDriven:
//Axle revolutions integration
axleSpeedMpS = AxleRevolutionsInt.Integrate(timeSpan,
axleDiameterM * axleDiameterM / (4.0f * (totalInertiaKgm2))
* (2.0f * transmissionRatio / axleDiameterM * (-Math.Abs(brakeRetardForceN)) - AxleForceN));
break;
case AxleDriveType.MotorDriven:
//Axle revolutions integration
if (TrainSpeedMpS == 0.0f)
{
dampingNs = 0.0f;
brakeRetardForceN = 0.0f;
}
axleSpeedMpS = AxleRevolutionsInt.Integrate(timeSpan,
axleDiameterM * axleDiameterM / (4.0f * (totalInertiaKgm2))
* (2.0f * transmissionRatio / axleDiameterM * motor.DevelopedTorqueNm * transmissionEfficiency
- Math.Abs(brakeRetardForceN) - (axleSpeedMpS > 0.0 ? Math.Abs(dampingNs) : 0.0f)) - AxleForceN);
//update motor values
motor.RevolutionsRad = axleSpeedMpS * 2.0f * transmissionRatio / (axleDiameterM);
motor.Update(timeSpan);
break;
case AxleDriveType.ForceDriven:
//Axle revolutions integration
if (TrainSpeedMpS > 0.01f)
{
axleSpeedMpS = AxleRevolutionsInt.Integrate(timeSpan,
(
driveForceN * transmissionEfficiency
- brakeRetardForceN
- slipDerivationMpSS * dampingNs
- Math.Abs(SlipSpeedMpS) * frictionN
- AxleForceN
)
/ totalInertiaKgm2
);
compensateAxleForceN = axleForceN + brakeRetardForceN;
if (Math.Abs(compensateAxleForceN) > Math.Abs(driveForceN))
{
compensateAxleForceN = driveForceN;
}
if (brakeRetardForceN > driveForceN && AxleSpeedMpS < 0.1f)
{
axleSpeedMpS = 0.0f;
axleForceN = -brakeRetardForceN + driveForceN;
compensateAxleForceN = driveForceN;
}
}
else if (TrainSpeedMpS < -0.01f)
{
axleSpeedMpS = AxleRevolutionsInt.Integrate(timeSpan,
(
driveForceN * transmissionEfficiency
+ brakeRetardForceN
- slipDerivationMpSS * dampingNs
+ Math.Abs(SlipSpeedMpS) * frictionN
- AxleForceN
)
/ totalInertiaKgm2
);
compensateAxleForceN = axleForceN - brakeRetardForceN;
if (Math.Abs(compensateAxleForceN) > Math.Abs(driveForceN))
{
compensateAxleForceN = driveForceN;
}
if (brakeRetardForceN > Math.Abs(driveForceN) && AxleSpeedMpS > -0.1f)
{
axleSpeedMpS = 0.0f;
axleForceN = brakeRetardForceN - driveForceN;
compensateAxleForceN = driveForceN;
}
}
else
{
if (Math.Abs(driveForceN) < 1f)
{
Reset();
axleSpeedMpS = 0.0f;
//axleForceN = 0.0f;
}
else
{
axleForceN = driveForceN - brakeRetardForceN;
compensateAxleForceN = driveForceN;
if (Math.Abs(axleSpeedMpS) < 0.01f)
{
Reset();
}
}
//Reset(TrainSpeedMpS);
//axleForceN = driveForceN - brakeRetardForceN;
//axleSpeedMpS = AxleRevolutionsInt.Value;
}
break;
default:
totalInertiaKgm2 = inertiaKgm2;
break;
}
if (timeSpan > 0.0f)
{
slipDerivationMpSS = (SlipSpeedMpS - previousSlipSpeedMpS) / timeSpan;
previousSlipSpeedMpS = SlipSpeedMpS;
slipDerivationPercentpS = (SlipSpeedPercent - previousSlipPercent) / timeSpan;
previousSlipPercent = SlipSpeedPercent;
}
//Stability Correction
if (StabilityCorrection)
{
if (slipDerivationPercentpS > 300.0f)
{
adhesionK += 0.0001f * slipDerivationPercentpS;
}
else
{
adhesionK = (adhesionK <= 0.7f) ? 0.7f : (adhesionK - 0.005f);
}
}
// Set output MotiveForce to actual value exclusive of brake force.
compensatedaxleForceN = CompensatedFilterMovingAverage.Update(Math.Abs(compensatedaxleForceN) > Math.Abs(driveForceN) ? driveForceN : compensateAxleForceN);
axleForceN = FilterMovingAverage.Update(Math.Abs(axleForceN) > Math.Abs(driveForceN) ? driveForceN : axleForceN);
}
/// <summary>
/// Main Update method
/// - computes slip characteristics to get new axle force
/// - computes axle dynamic model according to its driveType
/// - computes wheelslip indicators
/// </summary>
/// <param name="timeSpan"></param>
public virtual void Update(float timeSpan)
{
//Update axle force ( = k * loadTorqueNm)
axleForceN = AxleWeightN * SlipCharacteristics(AxleSpeedMpS - TrainSpeedMpS, TrainSpeedMpS, AdhesionK, AdhesionConditions, Adhesion2);
switch (driveType)
{
case AxleDriveType.NotDriven:
//Axle revolutions integration
axleSpeedMpS = AxleRevolutionsInt.Integrate(timeSpan,
axleDiameterM * axleDiameterM / (4.0f * (totalInertiaKgm2))
* (2.0f * transmissionRatio / axleDiameterM * (-Math.Abs(brakeRetardForceN)) - AxleForceN));
break;
case AxleDriveType.MotorDriven:
//Axle revolutions integration
if (TrainSpeedMpS == 0.0f)
{
dampingNs = 0.0f;
brakeRetardForceN = 0.0f;
}
axleSpeedMpS = AxleRevolutionsInt.Integrate(timeSpan,
axleDiameterM * axleDiameterM / (4.0f * (totalInertiaKgm2))
* (2.0f * transmissionRatio / axleDiameterM * motor.DevelopedTorqueNm * transmissionEfficiency
- Math.Abs(brakeRetardForceN) - (axleSpeedMpS > 0.0 ? Math.Abs(dampingNs) : 0.0f)) - AxleForceN);
//update motor values
motor.RevolutionsRad = axleSpeedMpS * 2.0f * transmissionRatio / (axleDiameterM);
motor.Update(timeSpan);
break;
case AxleDriveType.ForceDriven:
//Axle revolutions integration
if (TrainSpeedMpS > 0.01f)
{
axleSpeedMpS = AxleRevolutionsInt.Integrate(timeSpan,
(
driveForceN * transmissionEfficiency
- brakeRetardForceN
- slipDerivationMpSS * dampingNs
- Math.Abs(SlipSpeedMpS) * frictionN
- AxleForceN
)
/ totalInertiaKgm2
);
if (brakeRetardForceN > driveForceN && AxleSpeedMpS < 0.1f)
{
axleSpeedMpS = 0.0f;
axleForceN = -brakeRetardForceN + driveForceN;
}
}
else if (TrainSpeedMpS < -0.01f)
{
axleSpeedMpS = AxleRevolutionsInt.Integrate(timeSpan,
(
driveForceN * transmissionEfficiency
+ brakeRetardForceN
- slipDerivationMpSS * dampingNs
+ Math.Abs(SlipSpeedMpS) * frictionN
- AxleForceN
)
/ totalInertiaKgm2
);
if (brakeRetardForceN > Math.Abs(driveForceN) && AxleSpeedMpS > -0.1f)
{
axleSpeedMpS = 0.0f;
axleForceN = brakeRetardForceN - driveForceN;
}
}
else
{
if (Math.Abs(driveForceN) < 1f)
{
Reset();
axleSpeedMpS = 0.0f;
//axleForceN = 0.0f;
}
else
{
axleForceN = driveForceN - brakeRetardForceN;
if (Math.Abs(axleSpeedMpS) < 0.01f)
{
Reset();
}
}
//Reset(TrainSpeedMpS);
//axleForceN = driveForceN - brakeRetardForceN;
//axleSpeedMpS = AxleRevolutionsInt.Value;
}
break;
default:
totalInertiaKgm2 = inertiaKgm2;
break;
}
if (timeSpan > 0.0f)
{
slipDerivationMpSS = (SlipSpeedMpS - previousSlipSpeedMpS) / timeSpan;
previousSlipSpeedMpS = SlipSpeedMpS;
slipDerivationPercentpS = (SlipSpeedPercent - previousSlipPercent) / timeSpan;
previousSlipPercent = SlipSpeedPercent;
}
//Stability Correction
if (StabilityCorrection)
{
if (slipDerivationPercentpS > 300.0f)
{
adhesionK += 0.0001f * slipDerivationPercentpS;
}
else
{
adhesionK = (adhesionK <= 0.7f) ? 0.7f : (adhesionK - 0.005f);
}
}
axleForceN = FilterMovingAverage.Update(Math.Abs(axleForceN) > Math.Abs(driveForceN) ? driveForceN : axleForceN);
}
