// provides AoA limiting and ground track steering to pitch controllers (possibly should be moved into the attitude controller, but
// right now it collaborates too heavily with the ascent autopilot)
//
protected void attitudeTo(double desiredPitch)
{
double desiredHeading = OrbitalManeuverCalculator.HeadingForLaunchInclination(vessel, vesselState, autopilot.desiredInclination);
Vector3d desiredHeadingVector = Math.Sin(desiredHeading * UtilMath.Deg2Rad) * vesselState.east + Math.Cos(desiredHeading * UtilMath.Deg2Rad) * vesselState.north;
Vector3d desiredThrustVector = Math.Cos(desiredPitch * UtilMath.Deg2Rad) * desiredHeadingVector
+ Math.Sin(desiredPitch * UtilMath.Deg2Rad) * vesselState.up;
thrustVectorForNavball = desiredThrustVector;
desiredThrustVector = desiredThrustVector.normalized;
if (autopilot.limitAoA)
{
float fade = vesselState.dynamicPressure < autopilot.aoALimitFadeoutPressure ? (float)(autopilot.aoALimitFadeoutPressure / vesselState.dynamicPressure) : 1;
autopilot.currentMaxAoA = Math.Min(fade * autopilot.maxAoA, 180d);
autopilot.limitingAoA = vessel.altitude <mainBody.atmosphereDepth && Vector3.Angle(vesselState.surfaceVelocity, desiredThrustVector)> autopilot.currentMaxAoA;
if (autopilot.limitingAoA)
{
desiredThrustVector = Vector3.RotateTowards(vesselState.surfaceVelocity, desiredThrustVector, (float)(autopilot.currentMaxAoA * Mathf.Deg2Rad), 1).normalized;
}
}
double pitch = 90 - Vector3d.Angle(desiredThrustVector, vesselState.up);
double hdg;
if (pitch > 89.9)
{
hdg = desiredHeading;
}
else
{
hdg = MuUtils.ClampDegrees360(UtilMath.Rad2Deg * Math.Atan2(Vector3d.Dot(desiredThrustVector, vesselState.east), Vector3d.Dot(desiredThrustVector, vesselState.north)));
}
if (autopilot.forceRoll)
{
core.attitude.AxisControl(!vessel.Landed, !vessel.Landed, !vessel.Landed && vesselState.altitudeBottom > 50);
if (desiredPitch == 90.0)
{
core.attitude.attitudeTo(hdg, pitch, autopilot.turnRoll, this);
}
else
{
core.attitude.attitudeTo(hdg, pitch, autopilot.verticalRoll, this);
}
}
else
{
core.attitude.attitudeTo(desiredThrustVector, AttitudeReference.INERTIAL, this);
}
}
public override void OnFixedUpdate()
{
if (NavBallGuidance && autopilot != null && autopilot.ascentPath != null)
{
double angle = Math.PI / 180 * autopilot.ascentPath.FlightPathAngle(vesselState.altitudeASL, vesselState.speedSurface);
double heading = Math.PI / 180 * OrbitalManeuverCalculator.HeadingForLaunchInclination(vessel.mainBody, autopilot.desiredInclination, launchLatitude, OrbitalManeuverCalculator.CircularOrbitSpeed(vessel.mainBody, autopilot.desiredOrbitAltitude + mainBody.Radius));
Vector3d horizontalDir = Math.Cos(heading) * vesselState.north + Math.Sin(heading) * vesselState.east;
Vector3d dir = Math.Cos(angle) * horizontalDir + Math.Sin(angle) * vesselState.up;
core.target.UpdateDirectionTarget(dir);
}
}
public override void OnFixedUpdate()
{
if (NavBallGuidance && autopilot != null && autopilot.ascentPath != null)
{
double angle = UtilMath.Deg2Rad * autopilot.ascentPath.FlightPathAngle(vesselState.altitudeASL, vesselState.speedSurface);
double heading = UtilMath.Deg2Rad * OrbitalManeuverCalculator.HeadingForLaunchInclination(vessel, vesselState, autopilot.desiredInclination);
Vector3d horizontalDir = Math.Cos(heading) * vesselState.north + Math.Sin(heading) * vesselState.east;
Vector3d dir = Math.Cos(angle) * horizontalDir + Math.Sin(angle) * vesselState.up;
core.target.UpdateDirectionTarget(dir);
}
}
void DriveVerticalAscent(FlightCtrlState s)
{
if (timedLaunch)
{
status = "Awaiting liftoff";
core.attitude.AxisControl(false, false, false);
return;
}
if (!ascentPath.IsVerticalAscent(vesselState.altitudeASL, vesselState.speedSurface))
{
mode = AscentMode.GRAVITY_TURN;
}
if (autoThrottle && orbit.ApA > desiredOrbitAltitude)
{
mode = AscentMode.COAST_TO_APOAPSIS;
}
//during the vertical ascent we just thrust straight up at max throttle
if (forceRoll)
{ // pre-align roll unless correctiveSteering is active as it would just interfere with that
double desiredHeading = OrbitalManeuverCalculator.HeadingForLaunchInclination(vessel.mainBody, desiredInclination, launchLatitude, OrbitalManeuverCalculator.CircularOrbitSpeed(vessel.mainBody, desiredOrbitAltitude + mainBody.Radius));
core.attitude.attitudeTo(desiredHeading, 90, verticalRoll, this);
}
else
{
core.attitude.attitudeTo(Vector3d.up, AttitudeReference.SURFACE_NORTH, this);
}
core.attitude.AxisControl(!vessel.Landed, !vessel.Landed, !vessel.Landed && vesselState.altitudeBottom > 50);
if (autoThrottle)
{
core.thrust.targetThrottle = 1.0F;
}
if (!vessel.LiftedOff() || vessel.Landed)
{
status = "Awaiting liftoff";
}
else
{
status = "Vertical ascent";
}
}
// this provides ground track heading based on desired inclination and is what most consumers should call
protected void attitudeTo(double desiredPitch)
{
double desiredHeading = OrbitalManeuverCalculator.HeadingForLaunchInclination(vessel, vesselState, autopilot.desiredInclination);
attitudeTo(desiredPitch, desiredHeading);
}
void DriveCoastToApoapsis(FlightCtrlState s)
{
core.thrust.targetThrottle = 0;
double circularSpeed = OrbitalManeuverCalculator.CircularOrbitSpeed(mainBody, orbit.ApR);
double apoapsisSpeed = orbit.SwappedOrbitalVelocityAtUT(orbit.NextApoapsisTime(vesselState.time)).magnitude;
double circularizeBurnTime = (circularSpeed - apoapsisSpeed) / vesselState.limitedMaxThrustAccel;
//Once we get above the atmosphere, plan and execute the circularization maneuver.
//For orbits near the edge of the atmosphere, we can't wait until we break the atmosphere
//to start the burn, so we also compare the timeToAp with the expected circularization burn time.
//if ((vesselState.altitudeASL > mainBody.RealMaxAtmosphereAltitude())
// || (vesselState.limitedMaxThrustAccel > 0 && orbit.timeToAp < circularizeBurnTime / 1.8))
// Sarbian : removed the special case for now. Some ship where turning while still in atmosphere
if (vesselState.altitudeASL > mainBody.RealMaxAtmosphereAltitude())
{
if (autodeploySolarPanels)
{
core.solarpanel.ExtendAll();
}
mode = AscentMode.CIRCULARIZE;
core.warp.MinimumWarp();
return;
}
//if our apoapsis has fallen too far, resume the gravity turn
if (orbit.ApA < desiredOrbitAltitude - 1000.0)
{
mode = AscentMode.GRAVITY_TURN;
core.warp.MinimumWarp();
return;
}
//point prograde and thrust gently if our apoapsis falls below the target
//core.attitude.attitudeTo(Vector3d.forward, AttitudeReference.ORBIT, this);
// Actually I have a better idea: Don't initiate orientation changes when there's a chance that our main engine
// might reignite. There won't be enough control authority to counteract that much momentum change.
// - Starwaster
core.thrust.targetThrottle = 0;
double desiredHeading = MathExtensions.Deg2Rad * OrbitalManeuverCalculator.HeadingForLaunchInclination(vessel.mainBody, desiredInclination, launchLatitude, OrbitalManeuverCalculator.CircularOrbitSpeed(vessel.mainBody, desiredOrbitAltitude + mainBody.Radius));
Vector3d desiredHeadingVector = Math.Sin(desiredHeading) * vesselState.east + Math.Cos(desiredHeading) * vesselState.north;
double desiredFlightPathAngle = ascentPath.FlightPathAngle(vesselState.altitudeASL, vesselState.speedSurface);
Vector3d desiredThrustVector = Math.Cos(desiredFlightPathAngle * MathExtensions.Deg2Rad) * desiredHeadingVector
+ Math.Sin(desiredFlightPathAngle * MathExtensions.Deg2Rad) * vesselState.up;
core.attitude.attitudeTo(desiredThrustVector.normalized, AttitudeReference.INERTIAL, this);
if (autoThrottle && orbit.ApA < desiredOrbitAltitude)
{
core.attitude.attitudeTo(Vector3d.forward, AttitudeReference.INERTIAL, this);
core.thrust.targetThrottle = ThrottleToRaiseApoapsis(orbit.ApR, desiredOrbitAltitude + mainBody.Radius);
}
if (core.node.autowarp)
{
//warp at x2 physical warp:
core.warp.WarpPhysicsAtRate(2);
}
status = "Coasting to edge of atmosphere";
}
void DriveGravityTurn(FlightCtrlState s)
{
//stop the gravity turn when our apoapsis reaches the desired altitude
if (autoThrottle && orbit.ApA > desiredOrbitAltitude)
{
mode = AscentMode.COAST_TO_APOAPSIS;
return;
}
//if we've fallen below the turn start altitude, go back to vertical ascent
if (ascentPath.IsVerticalAscent(vesselState.altitudeASL, vesselState.speedSurface))
{
mode = AscentMode.VERTICAL_ASCENT;
return;
}
if (autoThrottle)
{
core.thrust.targetThrottle = ThrottleToRaiseApoapsis(orbit.ApR, desiredOrbitAltitude + mainBody.Radius);
if (core.thrust.targetThrottle < 1.0F)
{
//when we are bringing down the throttle to make the apoapsis accurate, we're liable to point in weird
//directions because thrust goes down and so "difficulty" goes up. so just burn prograde
core.attitude.attitudeTo(Vector3d.forward, AttitudeReference.ORBIT, this);
status = "Fine tuning apoapsis";
return;
}
}
//transition gradually from the rotating to the non-rotating reference frame. this calculation ensures that
//when our maximum possible apoapsis, given our orbital energy, is desiredOrbitalRadius, then we are
//fully in the non-rotating reference frame and thus doing the correct calculations to get the right inclination
double GM = mainBody.gravParameter;
double potentialDifferenceWithApoapsis = GM / vesselState.radius - GM / (mainBody.Radius + desiredOrbitAltitude);
double verticalSpeedForDesiredApoapsis = Math.Sqrt(2 * potentialDifferenceWithApoapsis);
double referenceFrameBlend = Mathf.Clamp((float)(vesselState.speedOrbital / verticalSpeedForDesiredApoapsis), 0.0F, 1.0F);
Vector3d actualVelocityUnit = ((1 - referenceFrameBlend) * vesselState.surfaceVelocity.normalized
+ referenceFrameBlend * vesselState.orbitalVelocity.normalized).normalized;
double desiredHeading = MathExtensions.Deg2Rad * OrbitalManeuverCalculator.HeadingForLaunchInclination(vessel.mainBody, desiredInclination, launchLatitude, OrbitalManeuverCalculator.CircularOrbitSpeed(vessel.mainBody, desiredOrbitAltitude + mainBody.Radius));
Vector3d desiredHeadingVector = Math.Sin(desiredHeading) * vesselState.east + Math.Cos(desiredHeading) * vesselState.north;
double desiredFlightPathAngle = ascentPath.FlightPathAngle(vesselState.altitudeASL, vesselState.speedSurface);
Vector3d desiredVelocityUnit = Math.Cos(desiredFlightPathAngle * Math.PI / 180) * desiredHeadingVector
+ Math.Sin(desiredFlightPathAngle * Math.PI / 180) * vesselState.up;
Vector3d desiredThrustVector = desiredVelocityUnit;
if (correctiveSteering)
{
Vector3d velocityError = (desiredVelocityUnit - actualVelocityUnit);
const double Kp = 5.0; //control gain
//"difficulty" scales the controller gain to account for the difficulty of changing a large velocity vector given our current thrust
double difficulty = vesselState.surfaceVelocity.magnitude / (50 + 10 * vesselState.ThrustAccel(core.thrust.targetThrottle));
if (difficulty > 5)
{
difficulty = 5;
}
if (vesselState.limitedMaxThrustAccel == 0)
{
difficulty = 1.0; //so we don't freak out over having no thrust between stages
}
Vector3d steerOffset = Kp * difficulty * velocityError;
//limit the amount of steering to 10 degrees. Furthermore, never steer to a FPA of > 90 (that is, never lean backward)
double maxOffset = 10 * Math.PI / 180;
if (desiredFlightPathAngle > 80)
{
maxOffset = (90 - desiredFlightPathAngle) * Math.PI / 180;
}
if (steerOffset.magnitude > maxOffset)
{
steerOffset = maxOffset * steerOffset.normalized;
}
desiredThrustVector += steerOffset;
}
desiredThrustVector = desiredThrustVector.normalized;
if (limitAoA)
{
float fade = vesselState.dynamicPressure < aoALimitFadeoutPressure ? (float)(aoALimitFadeoutPressure / vesselState.dynamicPressure) : 1;
currentMaxAoA = Math.Min(fade * maxAoA, 180d);
limitingAoA = vessel.altitude <mainBody.atmosphereDepth && Vector3.Angle(vesselState.surfaceVelocity, desiredThrustVector)> currentMaxAoA;
if (limitingAoA)
{
desiredThrustVector = Vector3.RotateTowards(vesselState.surfaceVelocity, desiredThrustVector, (float)(currentMaxAoA * Mathf.Deg2Rad), 1).normalized;
}
}
if (forceRoll && Vector3.Angle(vesselState.up, vesselState.forward) > 7 && core.attitude.attitudeError < 5)
{
var pitch = 90 - Vector3.Angle(vesselState.up, desiredThrustVector);
var hdg = core.rover.HeadingToPos(vessel.CoM, vessel.CoM + desiredThrustVector);
core.attitude.attitudeTo(hdg, pitch, turnRoll, this);
}
else
{
core.attitude.attitudeTo(desiredThrustVector, AttitudeReference.INERTIAL, this);
}
status = "Gravity turn";
}
