diff --git a/src/loop_closure_base_2d.h b/src/loop_closure_base_2d.h
index a634af460da05548bd0f8d3b14c9bd4c49c8614d..97965a453329427a51e89e0b0cbabb0e0e518ba9 100644
--- a/src/loop_closure_base_2d.h
+++ b/src/loop_closure_base_2d.h
@@ -17,6 +17,7 @@
  **************************/
 #include "laser_scan.h"
 #include "scene_base.h"
+#include "scene_falko.h"
 
 /**************************
  *      Falko includes      *
@@ -52,11 +53,11 @@ public:
     /** \brief compare new scans against the trained set in order to find loop closures
      **/
     //virtual void findLoopClosure(std::list<cornerScene>& scenes, const cornerScene newScene){}
-    virtual void findLoopClosure(){}
+    //virtual void findLoopClosure(){}
 
     /** \brief update the scene struct with keypoints and descriptors
      **/
-    //virtual void extractScene(LaserScan &scan,LaserScanParams &scanParams){}
+    virtual std::shared_ptr<sceneFalko<falkolib::BSC>> extractScene(LaserScan &scan,LaserScanParams &scanParams){}
 
     /** \brief Convert scans from laserscanutils::LaserScan to falkolib::LaserScan object
      **/
diff --git a/src/loop_closure_falko.h b/src/loop_closure_falko.h
index 35be401349b4f18798590efdee265ec9e7af9c6b..e75c91d3cf01ad4447db0519f7c82db07733e373 100644
--- a/src/loop_closure_falko.h
+++ b/src/loop_closure_falko.h
@@ -51,7 +51,6 @@ private:
 public:
     Extr extractor_;
     M matcher_;
-    int test=1;
 
     /** \brief Constructor
     **/
@@ -67,7 +66,7 @@ public:
 
     /** \brief update the scene struct with keypoints and descriptors
      **/
-    std::shared_ptr<sceneFalko<D>> extractScene(LaserScan &scan,LaserScanParams &scanParams);
+    std::shared_ptr<sceneFalko<D>> extractScene(LaserScan &scan,LaserScanParams &scanParams) override;
 
     
 };
diff --git a/src/scene_base.h b/src/scene_base.h
index 4be0f75726c3881c66e0c69958bf944b7a7a877d..7e7dd89ec371c16e2a73dafe5bf025c3e2975cc5 100644
--- a/src/scene_base.h
+++ b/src/scene_base.h
@@ -18,6 +18,7 @@ namespace laserscanutils
 struct sceneBase{
     //std::vector<falkolib::FALKO> keypointsList;
     //std::vector<D> descriptorsList;
+    std::vector<double> test;
 };
 
 
diff --git a/src/scene_falko.h b/src/scene_falko.h
index 73f857fe6a6122596bd9885d3db60491658e4559..65b725348958189309ffd629c187393bfedd1af8 100644
--- a/src/scene_falko.h
+++ b/src/scene_falko.h
@@ -35,7 +35,7 @@ namespace laserscanutils
 {
 
 template <typename D>
-struct sceneFalko : sceneBase{
+struct sceneFalko : public sceneBase{
     std::vector<falkolib::FALKO> keypointsList;
     std::vector<D> descriptorsList;
 };