LASGeometryUpdater Class Reference

#include <LASGeometryUpdater.h>

Public Member Functions
void	ApplyBeamKinkCorrections (LASGlobalData< LASCoordinateSet > &) const
void	EndcapUpdate (LASEndcapAlignmentParameterSet &, LASGlobalData< LASCoordinateSet > &)
	LASGeometryUpdater (LASGlobalData< LASCoordinateSet > &, LASConstants &)
void	SetMisalignmentFromRefGeometry (bool)
void	SetReverseDirection (bool)
void	TrackerUpdate (LASEndcapAlignmentParameterSet &, LASBarrelAlignmentParameterSet &, AlignableTracker &)

Private Attributes
bool	isMisalignmentFromRefGeometry
bool	isReverseDirection
LASConstants	lasConstants
LASGlobalData< LASCoordinateSet >	nominalCoordinates

Detailed Description

Definition at line 16 of file LASGeometryUpdater.h.

Constructor & Destructor Documentation

LASGeometryUpdater()

LASGeometryUpdater::LASGeometryUpdater	(	LASGlobalData< LASCoordinateSet > &	aNominalCoordinates,
		LASConstants &	aLasConstants
	)

constructor providing access to the nominal coordinates and the constants - for the moment, both objects are passed here, later it should be sufficient to pass only the constants and to fill the nominalCoordinates locally from that

Definition at line 11 of file LASGeometryUpdater.cc.

References aNominalCoordinates, isMisalignmentFromRefGeometry, isReverseDirection, lasConstants, and nominalCoordinates.

                                                                    {
  nominalCoordinates = aNominalCoordinates;
  isReverseDirection = false;
  isMisalignmentFromRefGeometry = false;
  lasConstants = aLasConstants;
}

Member Function Documentation

ApplyBeamKinkCorrections()

void LASGeometryUpdater::ApplyBeamKinkCorrections

(

LASGlobalData< LASCoordinateSet > &

measuredCoordinates

)

const

this function reads the beam kinks from the lasConstants and applies them to the set of measured global phi positions

first we apply the endcap beamsplitter kink corrections for TEC+/- in one go
alignment tube beamsplitter & mirror kink corrections TBD.

Definition at line 23 of file LASGeometryUpdater.cc.

References EcalCondDBWriter_cfi::beam, LASConstants::GetEndcapBsKink(), LASCoordinateSet::GetPhi(), LASConstants::GetTecBsZPosition(), LASGlobalData< T >::GetTECEntry(), LASConstants::GetTecRadius(), LASConstants::GetTecZPosition(), lasConstants, relativeConstraints::ring, LASCoordinateSet::SetPhi(), and funct::tan().

Referenced by LaserAlignment::endRunProduce().

                                                                                                            {
  for (unsigned int det = 0; det < 2; ++det) {
    for (unsigned int ring = 0; ring < 2; ++ring) {
      for (unsigned int beam = 0; beam < 8; ++beam) {
        // corrections have different sign for TEC+/-
        const double endcapSign = det == 0 ? 1. : -1.;

        // the correction is applied to the last 4 disks
        for (unsigned int disk = 5; disk < 9; ++disk) {
          measuredCoordinates.GetTECEntry(det, ring, beam, disk)
              .SetPhi(measuredCoordinates.GetTECEntry(det, ring, beam, disk).GetPhi() -
                      tan(lasConstants.GetEndcapBsKink(det, ring, beam)) / lasConstants.GetTecRadius(ring) *
                          (lasConstants.GetTecZPosition(det, disk) - endcapSign * lasConstants.GetTecBsZPosition(det)));
        }
      }
    }
  }

}

EndcapUpdate()

void LASGeometryUpdater::EndcapUpdate	(	LASEndcapAlignmentParameterSet &	endcapParameters,
		LASGlobalData< LASCoordinateSet > &	measuredCoordinates
	)

apply the endcap alignment parameters in the LASEndcapAlignmentParameterSet to the Measurements (TEC2TEC only) and the AlignableTracker object

Definition at line 52 of file LASGeometryUpdater.cc.

References EcalCondDBWriter_cfi::beam, funct::cos(), LASEndcapAlignmentParameterSet::GetDiskParameter(), LASCoordinateSet::GetPhi(), LASGlobalData< T >::GetTEC2TECEntry(), nominalCoordinates, CosmicsPD_Skims::radius, LASCoordinateSet::SetPhi(), funct::sin(), and LASGlobalLoop::TEC2TECLoop().

Referenced by LaserAlignment::endRunProduce().

                                                                                            {
  // radius of TEC ring4 laser in mm
  const double radius = 564.;

  // loop objects and its variables
  LASGlobalLoop moduleLoop;
  int det = 0, beam = 0, disk = 0;

  // update the TEC2TEC measurements
  do {
    // the measured phi value for this module
    const double currentPhi = measuredCoordinates.GetTEC2TECEntry(det, beam, disk).GetPhi();

    // the correction to phi from the endcap algorithm;
    // it is defined such that the correction is to be subtracted
    double phiCorrection = 0.;

    // plain phi component
    phiCorrection -= endcapParameters.GetDiskParameter(det, disk, 0).first;

    // phi component from x deviation
    phiCorrection += sin(nominalCoordinates.GetTEC2TECEntry(det, beam, disk).GetPhi()) / radius *
                     endcapParameters.GetDiskParameter(det, disk, 1).first;

    // phi component from y deviation
    phiCorrection -= cos(nominalCoordinates.GetTEC2TECEntry(det, beam, disk).GetPhi()) / radius *
                     endcapParameters.GetDiskParameter(det, disk, 2).first;

    measuredCoordinates.GetTEC2TECEntry(det, beam, disk).SetPhi(currentPhi - phiCorrection);

  } while (moduleLoop.TEC2TECLoop(det, beam, disk));
}

SetMisalignmentFromRefGeometry()

void LASGeometryUpdater::SetMisalignmentFromRefGeometry

(

bool

isSet

)

Definition at line 301 of file LASGeometryUpdater.cc.

References isMisalignmentFromRefGeometry.

Referenced by LaserAlignment::endRunProduce().

{ isMisalignmentFromRefGeometry = isSet; }

SetReverseDirection()

void LASGeometryUpdater::SetReverseDirection

(

bool

isSet

)

Definition at line 296 of file LASGeometryUpdater.cc.

References isReverseDirection.

Referenced by LaserAlignment::endRunProduce().

{ isReverseDirection = isSet; }

TrackerUpdate()

void LASGeometryUpdater::TrackerUpdate	(	LASEndcapAlignmentParameterSet &	endcapParameters,
		LASBarrelAlignmentParameterSet &	barrelParameters,
		AlignableTracker &	theAlignableTracker
	)

merge the output from endcap and barrel algorithms and update the AlignableTracker object

the AlignableTracker input object is expected to be perfectly aligned!!

Definition at line 92 of file LASGeometryUpdater.cc.

References AlignableTracker::endCaps(), LASEndcapAlignmentParameterSet::GetDiskParameter(), LASBarrelAlignmentParameterSet::GetParameter(), AlignableTracker::innerHalfBarrels(), isMisalignmentFromRefGeometry, isReverseDirection, AlignableTracker::outerHalfBarrels(), and makeMuonMisalignmentScenario::wheel.

Referenced by LaserAlignment::endRunProduce().

                                                                              {
  // this constant defines the sense of *ALL* translations/rotations
  // of the alignables in the AlignableTracker object
  const int direction = (isReverseDirection || isMisalignmentFromRefGeometry) ? -1 : 1;

  // first, we access the half barrels of TIB and TOB
  const align::Alignables& theOuterHalfBarrels = theAlignableTracker.outerHalfBarrels();
  const align::Alignables& theInnerHalfBarrels = theAlignableTracker.innerHalfBarrels();

  // then the TECs and treat them also as half barrels
  const align::Alignables& theEndcaps = theAlignableTracker.endCaps();

  // re-arrange to match the structure in LASBarrelAlignmentParameterSet and simplify the loop
  // 2 (TIB+), 3 (TIB-), 4 (TOB+), 5 (TOB-)
  align::Alignables theHalfBarrels(6);
  theHalfBarrels.at(0) = theEndcaps.at(0);           // TEC+
  theHalfBarrels.at(1) = theEndcaps.at(1);           // TEC-
  theHalfBarrels.at(2) = theInnerHalfBarrels.at(1);  // TIB+
  theHalfBarrels.at(3) = theInnerHalfBarrels.at(0);  // TIB-
  theHalfBarrels.at(4) = theOuterHalfBarrels.at(1);  // TOB+
  theHalfBarrels.at(5) = theOuterHalfBarrels.at(0);  // TOB-

  // the z positions of the lower/upper-z halfbarrel_end_faces / outer_TEC_disks (in mm)
  // indices are: halfbarrel (0-5), endface(0=lowerZ,1=upperZ)
  std::vector<std::vector<double> > halfbarrelEndfaceZPositions(6, std::vector<double>(2, 0.));
  halfbarrelEndfaceZPositions.at(0).at(0) = 1322.5;
  halfbarrelEndfaceZPositions.at(0).at(1) = 2667.5;
  halfbarrelEndfaceZPositions.at(1).at(0) = -2667.5;
  halfbarrelEndfaceZPositions.at(1).at(1) = -1322.5;
  halfbarrelEndfaceZPositions.at(2).at(0) = 300.;
  halfbarrelEndfaceZPositions.at(2).at(1) = 700.;
  halfbarrelEndfaceZPositions.at(3).at(0) = -700.;
  halfbarrelEndfaceZPositions.at(3).at(1) = -300.;
  halfbarrelEndfaceZPositions.at(4).at(0) = 300.;
  halfbarrelEndfaceZPositions.at(4).at(1) = 1090.;
  halfbarrelEndfaceZPositions.at(5).at(0) = -1090.;
  halfbarrelEndfaceZPositions.at(5).at(1) = -300.;

  // z difference of half barrel end faces (= hb-length) in mm
  // do all this geometry stuff more intelligent later..
  std::vector<double> theBarrelLength(6, 0.);
  theBarrelLength.at(0) = 1345.;  // TEC
  theBarrelLength.at(1) = 1345.;
  theBarrelLength.at(2) = 400.;  // TIB
  theBarrelLength.at(3) = 400.;
  theBarrelLength.at(4) = 790.;  // TOB
  theBarrelLength.at(5) = 790.;

  // the halfbarrel centers as defined in the AlignableTracker object,
  // needed for offset corrections; code to be improved later
  std::vector<double> theHalfbarrelCenters(6, 0.);
  for (int halfbarrel = 0; halfbarrel < 6; ++halfbarrel) {
    theHalfbarrelCenters.at(halfbarrel) = theHalfBarrels.at(halfbarrel)->globalPosition().z() * 10.;  // in mm
  }

  // mm to cm conversion factor (use by division)
  const double fromMmToCm = 10.;

  // half barrel loop (no TECs -> det>1)
  for (int halfBarrel = 2; halfBarrel < 6; ++halfBarrel) {
    // A word on the factors of -1 in the below move/rotate statements:
    //
    // Since it is not possible to misalign simulated low-level objects like SiStripDigis in CMSSW,
    // LAS monte carlo digis are always ideally aligned, and misalignment is introduced
    // by displacing the reference geometry (AlignableTracker) instead which is used for stripNumber->phi conversion.
    // Hence, in case MC are used in that way, factors of -1 must be introduced
    // for rotations around x,y and translations in x,y. The variable "xyDirection" takes care of this.
    //
    // However, for rotations around z (phi) there is a complication:
    // in the analytical AlignmentTubeAlgorithm, the alignment parameter phi (z-rotation)
    // is defined such that a positive value results in a positive contribution to the residual. In the real detector,
    // the opposite is true. The resulting additional factor of -1 thus compensates for the abovementioned reference geometry effect.
    //
    // this behavior can be reversed using the "direction" factor.

    // rotation around x axis = (dy1-dy2)/L
    const align::Scalar rxLocal = (barrelParameters.GetParameter(halfBarrel, 0, 2).first -
                                   barrelParameters.GetParameter(halfBarrel, 1, 2).first) /
                                  theBarrelLength.at(halfBarrel);
    theHalfBarrels.at(halfBarrel)->rotateAroundLocalX(direction * rxLocal);

    // rotation around y axis = (dx2-dx1)/L
    const align::Scalar ryLocal = (barrelParameters.GetParameter(halfBarrel, 1, 1).first -
                                   barrelParameters.GetParameter(halfBarrel, 0, 1).first) /
                                  theBarrelLength.at(halfBarrel);
    theHalfBarrels.at(halfBarrel)->rotateAroundLocalY(direction * ryLocal);

    // average rotation around z axis = (dphi1+dphi2)/2
    const align::Scalar rzLocal = (barrelParameters.GetParameter(halfBarrel, 0, 0).first +
                                   barrelParameters.GetParameter(halfBarrel, 1, 0).first) /
                                  2.;
    theHalfBarrels.at(halfBarrel)
        ->rotateAroundLocalZ(-1. * direction * rzLocal);  // this is phi, additional -1 here, see comment above

    // now that the rotational displacements are removed, the remaining translational offsets can be corrected for.
    // for this, the effect of the rotations is subtracted from the measured endface offsets

    // @@@ the +/-/-/+ signs for the correction parameters are not yet fully understood -
    // @@@ do they flip when switching from reference-geometry-misalignment to true misalignment???
    std::vector<double> correctedEndfaceOffsetsX(2, 0.);  // lowerZ/upperZ endface
    correctedEndfaceOffsetsX.at(0) =
        barrelParameters.GetParameter(halfBarrel, 0, 1).first +
        (theHalfbarrelCenters.at(halfBarrel) - halfbarrelEndfaceZPositions.at(halfBarrel).at(0)) * ryLocal;
    correctedEndfaceOffsetsX.at(1) =
        barrelParameters.GetParameter(halfBarrel, 1, 1).first -
        (halfbarrelEndfaceZPositions.at(halfBarrel).at(1) - theHalfbarrelCenters.at(halfBarrel)) * ryLocal;

    std::vector<double> correctedEndfaceOffsetsY(2, 0.);  // lowerZ/upperZ endface
    correctedEndfaceOffsetsY.at(0) =
        barrelParameters.GetParameter(halfBarrel, 0, 2).first -
        (theHalfbarrelCenters.at(halfBarrel) - halfbarrelEndfaceZPositions.at(halfBarrel).at(0)) * rxLocal;
    correctedEndfaceOffsetsY.at(1) =
        barrelParameters.GetParameter(halfBarrel, 1, 2).first +
        (halfbarrelEndfaceZPositions.at(halfBarrel).at(1) - theHalfbarrelCenters.at(halfBarrel)) * rxLocal;

    // average x displacement = (cd1+cd2)/2
    const align::GlobalVector dxLocal(
        (correctedEndfaceOffsetsX.at(0) + correctedEndfaceOffsetsX.at(1)) / 2. / fromMmToCm, 0., 0.);
    theHalfBarrels.at(halfBarrel)->move(direction * (dxLocal));

    // average y displacement = (cd1+cd2)/s
    const align::GlobalVector dyLocal(
        0., (correctedEndfaceOffsetsY.at(0) + correctedEndfaceOffsetsY.at(1)) / 2. / fromMmToCm, 0.);
    theHalfBarrels.at(halfBarrel)->move(direction * (dyLocal));
  }

  // now fit the endcaps into that alignment tube frame. the strategy is the following:
  //
  // 1. apply the parameters from the endcap algorithm to the individual disks
  // 2. the tec as a whole is rotated and moved such that the innermost disk (1) (= halfbarrel inner endface)
  //    reaches the position determined by the barrel algorithm.
  // 3. then, the TEC is twisted and sheared until the outermost disk (9) reaches nominal position
  //    (since it has been fixed there in the alignment tube frame). this resolves any common
  //    shear and torsion within the TEC coordinate frame.

  // shortcut to the z positions of the disks' mechanical structures (TEC+/-, 9*disk)
  std::vector<std::vector<double> > wheelZPositions(2, std::vector<double>(9, 0.));
  for (int wheel = 0; wheel < 9; ++wheel) {
    wheelZPositions.at(0).at(wheel) = theEndcaps.at(0)->components().at(wheel)->globalPosition().z();
    wheelZPositions.at(1).at(wheel) = theEndcaps.at(1)->components().at(wheel)->globalPosition().z();
  }

  // we can do this for both TECs in one go;
  // only real difference is the index change in the second argument to barrelParameters::GetParameter:
  // here the disk index changes from 0(+) to 1(-), since the end faces are sorted according to z (-->side=det)

  for (int det = 0; det < 2; ++det) {
    const int& side = det;

    // step 1: apply the endcap algorithm parameters

    // factors of -1. within the move/rotate statements: see comment above.
    // difference here: in the the endcap algorithm, the alignment parameter phi (z-rotation) is defined
    // in the opposite sense compared with the AT algorithm, thus the factor of -1 applies also to phi rotations.

    for (int wheel = 0; wheel < 9; ++wheel) {
      theEndcaps.at(det)->components().at(wheel)->rotateAroundLocalZ(
          direction * endcapParameters.GetDiskParameter(det, wheel, 0).first);
      const align::GlobalVector dXY(endcapParameters.GetDiskParameter(det, wheel, 1).first / fromMmToCm,
                                    endcapParameters.GetDiskParameter(det, wheel, 2).first / fromMmToCm,
                                    0.);
      theEndcaps.at(det)->components().at(wheel)->move(direction * dXY);
    }

    // step 2: attach the innermost disk (disk 1) by rotating/moving the complete endcap

    // rotation around z of disk 1
    const align::Scalar dphi1 = barrelParameters.GetParameter(det, side, 0).first;
    theEndcaps.at(det)->rotateAroundLocalZ(-1. * direction *
                                           dphi1);  // dphi1 is from the AT algorithm, so additional sign (s.above)

    // displacement in x,y of disk 1
    const align::GlobalVector dxy1(barrelParameters.GetParameter(det, side, 1).first / fromMmToCm,
                                   barrelParameters.GetParameter(det, side, 2).first / fromMmToCm,
                                   0.);
    theEndcaps.at(det)->move(direction * dxy1);

    // determine the resulting phi, x, y of disk 9 after step 2
    // the wrong sign for TEC- is soaked up by the reducedZ in step 3
    const align::Scalar resultingPhi9 =
        barrelParameters.GetParameter(det, 1, 0).first - barrelParameters.GetParameter(det, 0, 0).first;
    const align::GlobalVector resultingXY9(
        (barrelParameters.GetParameter(det, 1, 1).first - barrelParameters.GetParameter(det, 0, 1).first) / fromMmToCm,
        (barrelParameters.GetParameter(det, 1, 2).first - barrelParameters.GetParameter(det, 0, 2).first) / fromMmToCm,
        0.);

    // step 3: twist and shear back

    // the individual rotation/movement of the wheels is a function of their z-position
    for (int wheel = 0; wheel < 9; ++wheel) {
      const double reducedZ =
          (wheelZPositions.at(det).at(wheel) - wheelZPositions.at(det).at(0)) / theBarrelLength.at(det) * fromMmToCm;
      theEndcaps.at(det)->components().at(wheel)->rotateAroundLocalZ(-1. * direction * reducedZ *
                                                                     resultingPhi9);          // twist
      theEndcaps.at(det)->components().at(wheel)->move(direction * reducedZ * resultingXY9);  // shear
    }
  }
}

Member Data Documentation

isMisalignmentFromRefGeometry

bool LASGeometryUpdater::isMisalignmentFromRefGeometry

private

Definition at line 29 of file LASGeometryUpdater.h.

Referenced by LASGeometryUpdater(), SetMisalignmentFromRefGeometry(), and TrackerUpdate().

isReverseDirection

bool LASGeometryUpdater::isReverseDirection

private

Definition at line 28 of file LASGeometryUpdater.h.

Referenced by LASGeometryUpdater(), SetReverseDirection(), and TrackerUpdate().

lasConstants

LASConstants LASGeometryUpdater::lasConstants

private

Definition at line 27 of file LASGeometryUpdater.h.

Referenced by ApplyBeamKinkCorrections(), and LASGeometryUpdater().

nominalCoordinates

LASGlobalData<LASCoordinateSet> LASGeometryUpdater::nominalCoordinates

private

Definition at line 26 of file LASGeometryUpdater.h.

Referenced by EndcapUpdate(), and LASGeometryUpdater().