optimization updates

[debian/openrocket] / src / net / sf / openrocket / simulation / RK4SimulationStepper.java

diff --git a/src/net/sf/openrocket/simulation/RK4SimulationStepper.java b/src/net/sf/openrocket/simulation/RK4SimulationStepper.java
index 45be122dbdf215f7db4594b1f5b816ff5eaaaa58..07020f2252c0c3eda1a3c64755c4d083a4b7206b 100644 (file)
--- a/src/net/sf/openrocket/simulation/RK4SimulationStepper.java
+++ b/src/net/sf/openrocket/simulation/RK4SimulationStepper.java
@@ -8,6 +8,7 @@ import net.sf.openrocket.aerodynamics.FlightConditions;
 import net.sf.openrocket.aerodynamics.WarningSet;
 import net.sf.openrocket.logging.LogHelper;
 import net.sf.openrocket.models.atmosphere.AtmosphericConditions;
+import net.sf.openrocket.simulation.exception.SimulationCalculationException;
 import net.sf.openrocket.simulation.exception.SimulationException;
 import net.sf.openrocket.simulation.listeners.SimulationListenerHelper;
 import net.sf.openrocket.startup.Application;
@@ -21,6 +22,9 @@ public class RK4SimulationStepper extends AbstractSimulationStepper {
        
        private static final LogHelper log = Application.getLogger();
        
+       /** Random value with which to XOR the random seed value */
+       private static final int SEED_RANDOMIZATION = 0x23E3A01F;
+       
 
        /**
         * A recommended reasonably accurate time step.
@@ -50,8 +54,7 @@ public class RK4SimulationStepper extends AbstractSimulationStepper {
        private static final double MIN_TIME_STEP = 0.001;
        
 
-
-       private final Random random = new Random();
+       private Random random;
        
        
 
@@ -59,8 +62,6 @@ public class RK4SimulationStepper extends AbstractSimulationStepper {
        @Override
        public RK4SimulationStatus initialize(SimulationStatus original) {
                
-               log.info("Performing RK4SimulationStepper initialization");
-               
                RK4SimulationStatus status = new RK4SimulationStatus();
                
                status.copyFrom(original);
@@ -72,6 +73,8 @@ public class RK4SimulationStepper extends AbstractSimulationStepper {
                                Math.cos(sim.getLaunchRodAngle())
                                ));
                
+               this.random = new Random(original.getSimulationConditions().getRandomSeed() ^ SEED_RANDOMIZATION);
+               
                return status;
        }
        
@@ -155,11 +158,11 @@ public class RK4SimulationStepper extends AbstractSimulationStepper {
                
                double minTimeStep = status.getSimulationConditions().getTimeStep() / 20;
                if (store.timestep < minTimeStep) {
-                       log.debug("Too small time step " + store.timestep + " (limiting factor " + limitingValue + "), using " +
+                       log.verbose("Too small time step " + store.timestep + " (limiting factor " + limitingValue + "), using " +
                                        minTimeStep + " instead.");
                        store.timestep = minTimeStep;
                } else {
-                       log.debug("Selected time step " + store.timestep + " (limiting factor " + limitingValue + ")");
+                       log.verbose("Selected time step " + store.timestep + " (limiting factor " + limitingValue + ")");
                }
                checkNaN(store.timestep);
                
@@ -169,13 +172,13 @@ public class RK4SimulationStepper extends AbstractSimulationStepper {
                 * diminished by it affecting only 1/6th of the total, so it's an acceptable error.
                 */
                double thrustEstimate = store.thrustForce;
-               store.thrustForce = calculateThrust(status, store.timestep, store.longitudalAcceleration,
+               store.thrustForce = calculateThrust(status, store.timestep, store.longitudinalAcceleration,
                                store.atmosphericConditions, true);
                double thrustDiff = Math.abs(store.thrustForce - thrustEstimate);
                // Log if difference over 1%, recompute if over 10%
                if (thrustDiff > 0.01 * thrustEstimate) {
                        if (thrustDiff > 0.1 * thrustEstimate + 0.001) {
-                               log.info("Thrust estimate differs from correct value by " +
+                               log.debug("Thrust estimate differs from correct value by " +
                                                (Math.rint(1000 * (thrustDiff + 0.000001) / thrustEstimate) / 10.0) + "%," +
                                                " estimate=" + thrustEstimate +
                                                " correct=" + store.thrustForce +
@@ -183,7 +186,7 @@ public class RK4SimulationStepper extends AbstractSimulationStepper {
                                                ", recomputing k1 parameters");
                                k1 = computeParameters(status, store);
                        } else {
-                               log.debug("Thrust estimate differs from correct value by " +
+                               log.verbose("Thrust estimate differs from correct value by " +
                                                (Math.rint(1000 * (thrustDiff + 0.000001) / thrustEstimate) / 10.0) + "%," +
                                                " estimate=" + thrustEstimate +
                                                " correct=" + store.thrustForce +
@@ -253,6 +256,13 @@ public class RK4SimulationStepper extends AbstractSimulationStepper {
                status.setSimulationTime(status.getSimulationTime() + store.timestep);
                
                status.setPreviousTimeStep(store.timestep);
+               
+               // Verify that values don't run out of range
+               if (status.getRocketVelocity().length2() > 1e18 ||
+                               status.getRocketPosition().length2() > 1e18 ||
+                               status.getRocketRotationVelocity().length2() > 1e18) {
+                       throw new SimulationCalculationException("Simulation values exceeded limits");
+               }
        }
        
        
@@ -357,8 +367,9 @@ public class RK4SimulationStepper extends AbstractSimulationStepper {
                        double momZ = store.forces.getCroll() * dynP * refArea * refLength;
                        
                        // Compute acceleration in rocket coordinates
-                       store.angularAcceleration = new Coordinate(momX / store.massData.getLongitudalInertia(),
-                                               momY / store.massData.getLongitudalInertia(), momZ / store.massData.getRotationalInertia());
+                       store.angularAcceleration = new Coordinate(momX / store.massData.getLongitudinalInertia(),
+                                               momY / store.massData.getLongitudinalInertia(),
+                                               momZ / store.massData.getRotationalInertia());
                        
                        store.rollAcceleration = store.angularAcceleration.z;
                        // TODO: LOW: This should be hypot, but does it matter?
@@ -557,7 +568,7 @@ public class RK4SimulationStepper extends AbstractSimulationStepper {
                }
                
                if (store.flightConditions != null) {
-                       data.setValue(FlightDataType.TYPE_VELOCITY_TOTAL, store.flightConditions.getVelocity());
+                       data.setValue(FlightDataType.TYPE_VELOCITY_TOTAL, status.getRocketVelocity().length());
                        data.setValue(FlightDataType.TYPE_MACH_NUMBER, store.flightConditions.getMach());
                }
                
@@ -576,6 +587,8 @@ public class RK4SimulationStepper extends AbstractSimulationStepper {
                }
                if (store.massData != null) {
                        data.setValue(FlightDataType.TYPE_MASS, store.massData.getCG().weight);
+                       data.setValue(FlightDataType.TYPE_LONGITUDINAL_INERTIA, store.massData.getLongitudinalInertia());
+                       data.setValue(FlightDataType.TYPE_ROTATIONAL_INERTIA, store.massData.getRotationalInertia());
                }
                
                data.setValue(FlightDataType.TYPE_THRUST_FORCE, store.thrustForce);
@@ -667,7 +680,7 @@ public class RK4SimulationStepper extends AbstractSimulationStepper {
                
                public FlightConditions flightConditions;
                
-               public double longitudalAcceleration = Double.NaN;
+               public double longitudinalAcceleration = Double.NaN;
                
                public MassData massData;