/// <summary>
/// Returns the rotational speed profile to rotate the robot
/// </summary>
/// <param name="robot"></param>
/// <param name="start"></param>
/// <param name="end"></param>
/// <returns></returns>
private TrapezoidalProfile CreateRotationProfile(RobotParams robot, double start, double end, double time, double vel)
{
double accel = GroundToRotational(robot, robot.MaxAcceleration);
double maxvel = GroundToRotational(robot, vel);
double diff = end - start;
if (diff > 180.0)
{
diff -= 360.0;
}
else if (diff <= -180.0)
{
diff += 360.0;
}
TrapezoidalProfile tp;
tp = new TrapezoidalProfile(accel, maxvel);
tp.Update(diff, 0.0, 0.0);
if (tp.TotalTime > time)
{
throw new SwerveDriveModifier.VelocitySplitException();
}
return(tp);
}
public override Dictionary <string, PathSegment[]> ModifyPath(RobotParams robot, RobotPath path, PathSegment[] segs, double rotvel)
{
Dictionary <string, PathSegment[]> result = new Dictionary <string, PathSegment[]>();
if (segs == null)
{
return(null);
}
double total = segs[segs.Length - 1].GetValue("time");
double rtime = total - path.FacingAngleStartDelay - path.FacingAngleEndDelay;
TrapezoidalProfile profile = CreateRotationProfile(robot, path.StartFacingAngle, path.EndFacingAngle, rtime, rotvel);
if (profile == null)
{
throw new DriveModifier.VelocitySplitException();
}
PathSegment[] fl = new PathSegment[segs.Length];
PathSegment[] fr = new PathSegment[segs.Length];
PathSegment[] bl = new PathSegment[segs.Length];
PathSegment[] br = new PathSegment[segs.Length];
result["fl"] = fl;
result["fr"] = fr;
result["bl"] = bl;
result["br"] = br;
for (int i = 0; i < segs.Length; i++)
{
//
// The time in the path
//
double time = segs[i].GetValue("time");
//
// The current facing angle based on the rotational trapezoidal profile
//
double current = XeroUtils.BoundDegrees(path.StartFacingAngle + profile.GetDistance(time - path.FacingAngleStartDelay));
//
// Get the required velocity to perform the rotation. This is the
// linear ground based velocity for the wheel that must be applied to
// each wheel in direction perpendicular to the vector from the center of
// the robot to the center of the wheel.
//
double rv = RotationalToGround(robot, profile.GetVelocity(time - path.FacingAngleStartDelay));
double ra = RotationalToGround(robot, profile.GetAcceleration(time - path.FacingAngleStartDelay));
//
// Get the velocity vector and acceleration vector relative to each of the
// wheels to rotate the robot based on the desired rotational velocity.
//
XeroVector rotflvel = GetWheelPerpendicularVector(robot, Wheel.FL, rv);
XeroVector rotfrvel = GetWheelPerpendicularVector(robot, Wheel.FR, rv);
XeroVector rotblvel = GetWheelPerpendicularVector(robot, Wheel.BL, rv);
XeroVector rotbrvel = GetWheelPerpendicularVector(robot, Wheel.BR, rv);
XeroVector rotflacc = GetWheelPerpendicularVector(robot, Wheel.FL, ra);
XeroVector rotfracc = GetWheelPerpendicularVector(robot, Wheel.FR, ra);
XeroVector rotblacc = GetWheelPerpendicularVector(robot, Wheel.BL, ra);
XeroVector rotbracc = GetWheelPerpendicularVector(robot, Wheel.BR, ra);
//
// Get the translational velocity vector to follow the path
//
XeroVector pathvel = XeroVector.FromDegreesMagnitude(segs[i].GetValue("heading"), segs[i].GetValue("velocity")).RotateDegrees(-current);
XeroVector pathacc = XeroVector.FromDegreesMagnitude(segs[i].GetValue("heading"), segs[i].GetValue("acceleration")).RotateDegrees(-current);
//
// For each wheel, the velocity vector is the sum of the rotational vector and the translational vector
//
XeroVector flv = rotflvel + pathvel;
XeroVector frv = rotfrvel + pathvel;
XeroVector blv = rotblvel + pathvel;
XeroVector brv = rotbrvel + pathvel;
XeroVector fla = rotflacc + pathvel;
XeroVector fra = rotfracc + pathvel;
XeroVector bla = rotblacc + pathvel;
XeroVector bra = rotbracc + pathvel;
//
// Now calculate the wheel positions based on the path position and the
// facing angle
//
XeroVector flpos = new XeroVector(robot.Length / 2.0, robot.Width / 2.0).RotateDegrees(current).Translate(segs[i].GetValue("x"), segs[i].GetValue("y"));
XeroVector frpos = new XeroVector(robot.Length / 2.0, -robot.Width / 2.0).RotateDegrees(current).Translate(segs[i].GetValue("x"), segs[i].GetValue("y"));
XeroVector blpos = new XeroVector(-robot.Length / 2.0, robot.Width / 2.0).RotateDegrees(current).Translate(segs[i].GetValue("x"), segs[i].GetValue("y"));
XeroVector brpos = new XeroVector(-robot.Length / 2.0, -robot.Width / 2.0).RotateDegrees(current).Translate(segs[i].GetValue("x"), segs[i].GetValue("y"));
PathSegment newseg = new PathSegment(segs[i]);
newseg.SetValue("x", flpos.X);
newseg.SetValue("y", flpos.Y);
newseg.SetValue("velocity", flv.Magnitude());
newseg.SetValue("heading", flv.AngleDegrees());
newseg.SetValue("acceleration", fla.Magnitude());
fl[i] = newseg;
newseg = new PathSegment(segs[i]);
newseg.SetValue("x", frpos.X);
newseg.SetValue("y", frpos.Y);
newseg.SetValue("velocity", frv.Magnitude());
newseg.SetValue("heading", frv.AngleDegrees());
newseg.SetValue("acceleration", fra.Magnitude());
fr[i] = newseg;
newseg = new PathSegment(segs[i]);
newseg.SetValue("x", blpos.X);
newseg.SetValue("y", blpos.Y);
newseg.SetValue("velocity", blv.Magnitude());
newseg.SetValue("heading", blv.AngleDegrees());
newseg.SetValue("acceleration", bla.Magnitude());
bl[i] = newseg;
newseg = new PathSegment(segs[i]);
newseg.SetValue("x", brpos.X);
newseg.SetValue("y", brpos.Y);
newseg.SetValue("velocity", brv.Magnitude());
newseg.SetValue("heading", brv.AngleDegrees());
newseg.SetValue("acceleration", bra.Magnitude());
br[i] = newseg;
}
return(result);
}
