--- a/python/moving.py	Wed May 16 21:06:52 2018 -0400
+++ b/python/moving.py	Sun May 20 10:56:24 2018 -0400
@@ -1140,15 +1140,36 @@
     @staticmethod
     def concatenate(obj1, obj2, num = None):
         '''Concatenates two objects supposed to overlap temporally '''
+	if num is None:
+		newNum = obj1.getNum()
+	else:
+		newNum = num
         commonTimeInterval = obj1.commonTimeInterval(obj2)
         if commonTimeInterval.empty():
             print('The two objects\' time intervals do not overlap: obj1 {} and obj2 {}'.format(obj1.getTimeInterval(), obj2.getTimeInterval()))
-            return None
+            emptyInterval = TimeInterval(min(obj1.getLastInstant(),obj2.getLastInstant()) , max(obj1.getFirstInstant(),obj2.getFirstInstant()))
+            positions = Trajectory()
+            if obj1.existsAtInstant(emptyInterval.last):
+            	vitessex=(obj1.getPositionAtInstant(emptyInterval.last).x-obj2.getPositionAtInstant(emptyInterval.first).x)/(emptyInterval.last-emptyInterval.first)
+            	vitessey=(obj1.getPositionAtInstant(emptyInterval.last).y-obj2.getPositionAtInstant(emptyInterval.first).y)/(emptyInterval.last-emptyInterval.first)
+            	px,py=obj2.getPositionAtInstant(emptyInterval.first)
+            else :
+            	vitessex=(obj2.getPositionAtInstant(emptyInterval.last).x-obj1.getPositionAtInstant(emptyInterval.first).x)/(emptyInterval.last-emptyInterval.first)
+            	vitessey=(obj2.getPositionAtInstant(emptyInterval.last).y-obj1.getPositionAtInstant(emptyInterval.first).y)/(emptyInterval.last-emptyInterval.first)
+            	px,py=obj1.getPositionAtInstant(emptyInterval.first)
+            positions = Trajectory()
+            velocities = Trajectory()
+            for t in emptyInterval:
+            	positions.addPositionXY(px,py)
+            	velocities.addPositionXY(vitessex,vitessey)
+            	px+=vitessex
+            	py+=vitessey
+
+	    newObject = MovingObject(newNum, emptyInterval, positions, velocities, userType = obj1.getUserType())
+            return MovingObject.concatenate(MovingObject.concatenate(obj1, newObject),obj2)
+            
+            
         else:
-            if num is None:
-                newNum = obj1.getNum()
-            else:
-                newNum = num
             newTimeInterval = TimeInterval.union(obj1.getTimeInterval(), obj2.getTimeInterval())
             # positions
             positions = Trajectory()