breaking speeds from cost model + cost tuning

brouter-core/src/main/java/btools/router/KinematicModel.java

@@ -36,8 +36,8 @@ class KinematicModel extends OsmPathModel
   public double rightWaySpeed;
 
   // derived values
-  public double xweight; // the weight-factor between time and energy for cost calculation
-  public double timecost0; // minimum possible "energy-adjusted-time" per meter
+  public double pw; // balance power
+  public double cost0; // minimum possible cost per meter
   
   private int wayIdxMaxspeed;
   private int wayIdxMinspeed;
@@ -50,6 +50,9 @@ class KinematicModel extends OsmPathModel
 
   private boolean initDone = false;
 
+  private double lastEffectiveLimit;
+  private double lastBreakingSpeed;
+
   @Override
   public void init( BExpressionContextWay expctxWay, BExpressionContextNode expctxNode, Map<String,String> extraParams )
   {
@@ -77,8 +80,8 @@ class KinematicModel extends OsmPathModel
     leftWaySpeed = getParam( "leftWaySpeed", 12.f ) / 3.6;
     rightWaySpeed = getParam( "rightWaySpeed", 12.f ) / 3.6;
 
-    xweight = 1./( 2. * f_air * vmax * vmax * vmax - p_standby );
-    timecost0 = 1./vmax + xweight*(f_roll + f_air*vmax*vmax + p_standby/vmax );
+    pw = 2. * f_air * vmax * vmax * vmax - p_standby;
+    cost0 = (pw+p_standby)/vmax + f_roll + f_air*vmax*vmax;
   }
 
   protected float getParam( String name, float defaultValue )
@@ -111,10 +114,39 @@ class KinematicModel extends OsmPathModel
     return ctxNode.getBuildInVariable( nodeIdxMaxspeed ) / 3.6f;
   }
 
-  public double getMaxKineticEnergy()
+ /**
+  * get the effective speed limit from the way-limit and vmax/vmin
+  */
+  public double getEffectiveSpeedLimit( )
   {
-    // determine maximum possible speed and kinetic energy
-    double mspeed = Math.min( getWayMaxspeed(), Math.max( getWayMinspeed(), vmax ) );
-    return 0.5*totalweight*mspeed*mspeed;
+    return Math.min( getWayMaxspeed(), Math.max( getWayMinspeed(), vmax ) );
   }
+
+ /**
+  * get the breaking speed for current balance-power (pw) and effective speed limit (vl)
+  */
+  public double getBreakingSpeed( double vl )
+  {
+    if ( vl == lastEffectiveLimit )
+    {
+      return lastBreakingSpeed;
+    }
+
+    double v = vl*0.8;
+    double pw2 = pw+p_standby;
+    double e = recup_efficiency;
+    double x0 = pw2/vl+f_air*e*vl*vl+(1.-e)*f_roll;
+    for(int i=0;i<5;i++)
+    { 
+      double v2 = v*v;
+      double x = pw2/v+f_air*e*v2 - x0;
+      double dx = 2.*e*f_air*v - pw2/v2;
+      v -= x/dx;
+    }
+    lastEffectiveLimit = vl;
+    lastBreakingSpeed = v;
+    
+    return v;
+  }
+
 }

brouter-core/src/main/java/btools/router/KinematicPath.java

@@ -42,13 +42,14 @@ final class KinematicPath extends OsmPath
     KinematicModel km = (KinematicModel)rc.pm;
     
     double cost = 0.;
+    double extraTime = 0.;
 
     if ( isStartpoint )
     {
       // for forward direction, we start with target speed
       if ( !rc.inverseDirection )
       {
-        cost = 0.5 * (1. - cosangle ) * 40. /  km.timecost0; // 40 seconds turn penalty
+        extraTime = 0.5 * (1. - cosangle ) * 40.; // 40 seconds turn penalty
       }
     }
     else
@@ -107,7 +108,11 @@ final class KinematicPath extends OsmPath
         if ( hasLeftWay && turnspeed > km.leftWaySpeed ) turnspeed = km.leftWaySpeed;
         if ( hasRightWay && turnspeed > km.rightWaySpeed ) turnspeed = km.rightWaySpeed;
         if ( hasResidential && turnspeed > residentialSpeed ) turnspeed = residentialSpeed;
-        if ( (lastpriorityclassifier < 20) ^ (priorityclassifier < 20) ) turnspeed = 0; // full stop for entering or leaving road network
+        if ( (lastpriorityclassifier < 20) ^ (priorityclassifier < 20) )
+        {
+          extraTime += 10.;
+          turnspeed = 0; // full stop for entering or leaving road network
+        }
       }
 
       cutEkin( km.totalweight, turnspeed ); // apply turnspeed
@@ -128,6 +133,9 @@ final class KinematicPath extends OsmPath
       message.costfactor = (float)(distanceCost/dist);
     }
 
+    cost += extraTime * km.pw /  km.cost0;
+    totalTime += extraTime;
+
     return cost + distanceCost;
   }
 
@@ -137,12 +145,14 @@ final class KinematicPath extends OsmPath
     // elevation force
     double fh = delta_h * km.totalweight * 9.81 / dist;
 
-    double emax = km.getMaxKineticEnergy();
+    double effectiveSpeedLimit = km.getEffectiveSpeedLimit();
+    double emax = 0.5*km.totalweight*effectiveSpeedLimit*effectiveSpeedLimit;
     if ( emax <= 0. )
     {
       return -1.;
     }
-    double elow = 0.7*emax; // recup phase below 70% energy (=84% vmax)
+    double vb = km.getBreakingSpeed( effectiveSpeedLimit );
+    double elow = 0.5*km.totalweight*vb*vb;
 
     double elapsedTime = 0.; 
     double dissipatedEnergy = 0.;
@@ -209,7 +219,7 @@ final class KinematicPath extends OsmPath
     totalTime += elapsedTime;
     totalEnergy += dissipatedEnergy + dist*fh;
 
-    return (elapsedTime + km.xweight * dissipatedEnergy)/km.timecost0; // =cost
+    return (km.pw * elapsedTime + dissipatedEnergy)/km.cost0; // =cost
   }
 
   @Override

misc/profiles2/car-eco.brf

@@ -177,5 +177,10 @@ assign initialcost =
 
 assign maxspeed =
 
-       if or crossing=traffic_signals highway=traffic_signals then 0
+       if or crossing=traffic_signals highway=traffic_signals
+       then
+         switch greater way:priorityclassifier 24 5
+         switch greater way:priorityclassifier 22 3
+         switch greater way:priorityclassifier 20 1
+         0
        else 999

misc/profiles2/car-fast.brf

@@ -177,5 +177,10 @@ assign initialcost =
 
 assign maxspeed =
 
-       if or crossing=traffic_signals highway=traffic_signals then 0
+       if or crossing=traffic_signals highway=traffic_signals
+       then
+         switch greater way:priorityclassifier 24 5
+         switch greater way:priorityclassifier 22 3
+         switch greater way:priorityclassifier 20 1
+         0
        else 999