diff --git a/Detector/DetSegmentation/DetSegmentation/GridDriftChamber.h b/Detector/DetSegmentation/DetSegmentation/GridDriftChamber.h
index d6fcd5dffaa115de4883f358ee1ce4cf9ea27910..38e236c0d19d8b4419184510036b9db7e873e261 100644
--- a/Detector/DetSegmentation/DetSegmentation/GridDriftChamber.h
+++ b/Detector/DetSegmentation/DetSegmentation/GridDriftChamber.h
@@ -45,6 +45,7 @@ public:
   virtual CellID cellID(const Vector3D& aLocalPosition, const Vector3D& aGlobalPosition,
                         const VolumeID& aVolumeID) const;
   virtual double distanceTrackWire(const CellID& cID, const TVector3& hit_start, const TVector3& hit_end) const;
+  virtual void cellposition(const CellID& cID, TVector3& Wstart, TVector3& Wend) const;
 
 //  double phi(const CellID& cID) const;
   inline double cell_Size() const { return m_cellSize; }
@@ -86,13 +87,13 @@ public:
 
   inline auto returnAllWires() const { return m_wiresPositions; }
 
-  inline TVector3 returnWirePosition(double angle, int sign) const {
-    TVector3 w(0, 0, 0);
-    w.SetX(_currentRadius * std::cos(angle));
-    w.SetY(_currentRadius * std::sin(angle));
-    w.SetZ(sign * m_detectorLength / 2.0);
-    return w;
-  }
+//  inline TVector3 returnWirePosition(double angle, int sign) const {
+//    TVector3 w(0, 0, 0);
+//    w.SetX(_currentRadius * std::cos(angle));
+//    w.SetY(_currentRadius * std::sin(angle));
+//    w.SetZ(sign * m_detectorLength / 2.0);
+//    return w;
+//  }
 
   void updateParams(int layer)  const{
     auto it_end = layer_params.cend();
@@ -115,10 +116,10 @@ public:
     m_offset = offset;
  }
 
- inline double returnAlpha() const {
-   double alpha = 2 * std::asin(m_detectorLength * std::tan(m_epsilon0)/(2 * _currentRadius));
-   return alpha;
- }
+// inline double returnAlpha() const {
+//   double alpha = 2 * std::asin(m_detectorLength * std::tan(m_epsilon0)/(2 * _currentRadius));
+//   return alpha;
+// }
 
 protected:
 
@@ -126,6 +127,19 @@ protected:
   std::map<int,LAYER> layer_params; // <layer, {layerphi, R, eps, offset}>
   std::map<int, std::vector<std::pair<TVector3, TVector3> >> m_wiresPositions; // < layer, vec<WireMidpoint, WireDirection> >
 
+  inline TVector3 returnWirePosition(double angle, int sign) const {
+    TVector3 w(0, 0, 0);
+    w.SetX(_currentRadius * std::cos(angle));
+    w.SetY(_currentRadius * std::sin(angle));
+    w.SetZ(sign * m_detectorLength / 2.0);
+    return w;
+  }
+
+  inline double returnAlpha() const {
+    double alpha = 2 * std::asin(m_detectorLength * std::tan(m_epsilon0)/(2 * _currentRadius));
+    return alpha;
+ }
+
   double m_cellSize;
   double m_epsilon0;
   double m_detectorLength;
diff --git a/Detector/DetSegmentation/src/GridDriftChamber.cpp b/Detector/DetSegmentation/src/GridDriftChamber.cpp
index 4063a5ee229b86e67dc8664e5c50d345ebf085a6..b65edb2d3564a2f269526d946b67f8eb3d7f099d 100644
--- a/Detector/DetSegmentation/src/GridDriftChamber.cpp
+++ b/Detector/DetSegmentation/src/GridDriftChamber.cpp
@@ -72,8 +72,8 @@ double GridDriftChamber::phi(const CellID& cID) const {
   return binToPosition(phiValue, _currentLayerphi, m_offset);
 }
 
-double GridDriftChamber::distanceTrackWire(const CellID& cID, const TVector3& hit_start,
-                                           const TVector3& hit_end) const {
+void GridDriftChamber::cellposition(const CellID& cID, TVector3& Wstart,
+                                    TVector3& Wend) const {
 
   auto layerIndex = _decoder->get(cID, "layer");
   updateParams(layerIndex);
@@ -81,8 +81,26 @@ double GridDriftChamber::distanceTrackWire(const CellID& cID, const TVector3& hi
   double phi_start = phi(cID);
   double phi_end = phi_start + returnAlpha();
 
-  TVector3 Wstart = returnWirePosition(phi_start, -1); // The default centimeter unit in DD4hep
-  TVector3 Wend = returnWirePosition(phi_end, 1);   // The default centimeter unit in DD4hep
+  Wstart = returnWirePosition(phi_start, -1);
+  Wend = returnWirePosition(phi_end, 1);
+}
+
+
+
+double GridDriftChamber::distanceTrackWire(const CellID& cID, const TVector3& hit_start,
+                                           const TVector3& hit_end) const {
+
+//  auto layerIndex = _decoder->get(cID, "layer");
+//  updateParams(layerIndex);
+//
+//  double phi_start = phi(cID);
+//  double phi_end = phi_start + returnAlpha();
+
+//  TVector3 Wstart = returnWirePosition(phi_start, -1); // The default centimeter unit in DD4hep
+//  TVector3 Wend = returnWirePosition(phi_end, 1);   // The default centimeter unit in DD4hep
+  TVector3 Wstart = {0,0,0};
+  TVector3 Wend = {0,0,0};
+  cellposition(cID,Wstart,Wend);
 
   TVector3 a = hit_end - hit_start;
   TVector3 b = Wend - Wstart;