private double EvaluateInner(IBlackBox box)
{
const double angleLimit = System.Math.PI / 3.0;
// Init Box2D world.
WalkerWorld world = new WalkerWorld(_rng);
world.InitSimulationWorld();
// Create an interface onto the walker.
WalkerInterface walkerIface = world.CreateWalkerInterface();
// Create a neural net controller for the walker.
NeuralNetController walkerController = new NeuralNetController(walkerIface, box, world.SimulationParameters._frameRate);
Vec2 hipPos = walkerIface.LeftLegIFace.HipJointPosition;
double torsoYMin = hipPos.Y;
double torsoYMax = hipPos.Y;
// Run the simulation.
LegInterface leftLeg = walkerIface.LeftLegIFace;
LegInterface rightLeg = walkerIface.RightLegIFace;
//double totalAppliedTorque = 0.0;
int timestep = 0;
for (; timestep < _maxTimesteps; timestep++)
{
// Simulate one timestep.
world.Step();
walkerController.Step();
//totalAppliedTorque += walkerIface.TotalAppliedTorque;
// Track hip joint height and min/max extents.
hipPos = walkerIface.LeftLegIFace.HipJointPosition;
if (hipPos.Y < torsoYMin)
{
torsoYMin = hipPos.Y;
}
else if (hipPos.Y > torsoYMax)
{
torsoYMax = hipPos.Y;
}
double heightRange = torsoYMax - torsoYMin;
// Test for stopping conditions.
if (hipPos.X < -0.7 || hipPos.X > 150f || heightRange > 0.20 ||
System.Math.Abs(leftLeg.HipJointAngle) > angleLimit || System.Math.Abs(leftLeg.KneeJointAngle) > angleLimit ||
System.Math.Abs(rightLeg.HipJointAngle) > angleLimit || System.Math.Abs(rightLeg.KneeJointAngle) > angleLimit)
{ // Stop simulation.
break;
}
}
// Final fitness calcs / adjustments.
return(System.Math.Max(hipPos.X, 0.0));
}
/// <summary>
/// Evaluate the provided IBlackBox.
/// </summary>
public FitnessInfo Evaluate(IBlackBox box)
{
// Init Box2D world.
WalkerWorld world = new WalkerWorld(_rng);
world.InitSimulationWorld();
// Create an interface onto the walker.
WalkerInterface walkerIface = world.CreateWalkerInterface();
// Create a neural net controller for the walker.
NeuralNetController walkerController = new NeuralNetController(walkerIface, box);
// Run the simulation.
LegInterface leftLeg = walkerIface.LeftLegIFace;
LegInterface rightLeg = walkerIface.RightLegIFace;
double angleLimit = Math.PI * 0.8;
double totalAppliedTorque = 0.0;
int timestep = 0;
for (; timestep < _maxTimesteps; timestep++)
{
// Simulate one timestep.
world.Step();
walkerController.Step();
totalAppliedTorque += walkerIface.TotalAppliedTorque;
// Test for stopping conditions scoring zero.
if (leftLeg.FootHeight > 0.3f && rightLeg.FootHeight > 0.3f ||
Math.Abs(leftLeg.HipJointAngle) > angleLimit || Math.Abs(leftLeg.KneeJointAngle) > angleLimit ||
Math.Abs(rightLeg.HipJointAngle) > angleLimit || Math.Abs(rightLeg.KneeJointAngle) > angleLimit)
{ // Stop simulation.
return(new FitnessInfo(0.0, walkerIface.TorsoPosition.X));
}
// Test for scoring stopping conditions.
if (walkerIface.TorsoPosition.X < -0.7 || walkerIface.TorsoPosition.X > 150f || walkerIface.TorsoPosition.Y < 0.6f)
{ // Stop simulation.
break;
}
}
_evalCount++;
double fitness = Math.Max(0.0, walkerIface.TorsoPosition.X);
return(new FitnessInfo(fitness, walkerIface.TorsoPosition.X));
}