diff --git a/SoftRobotics/StepByStep-introduction/0-basic.py b/SoftRobotics/StepByStep-introduction/0-basic.py
index a343b8b..481cf5c 100644
--- a/SoftRobotics/StepByStep-introduction/0-basic.py
+++ b/SoftRobotics/StepByStep-introduction/0-basic.py
@@ -3,6 +3,6 @@ def createScene(rootNode):
 	rootNode.dt = 0.01			        # Time step
 	rootNode.gravity = [ 0., 0. ,0.]	# Gravitational acceleration applied on the entire scene
 
-	rootNode.addObject("DefaultAnimationLoop", name="animation loop")
+	rootNode.addObject("DefaultAnimationLoop", name="animation_loop")
 
 	rootNode.addChild("MyObject", bbox=[0,0,0,1,1,1])   # bbox is only needed here to define a non-zero simulation space since the scene is empty
diff --git a/SoftRobotics/StepByStep-introduction/9-boundary-conditions.py b/SoftRobotics/StepByStep-introduction/10-boundary-conditions.py
similarity index 100%
rename from SoftRobotics/StepByStep-introduction/9-boundary-conditions.py
rename to SoftRobotics/StepByStep-introduction/10-boundary-conditions.py
diff --git a/SoftRobotics/StepByStep-introduction/10-controller-access-data.py b/SoftRobotics/StepByStep-introduction/11-controller-access-data.py
similarity index 100%
rename from SoftRobotics/StepByStep-introduction/10-controller-access-data.py
rename to SoftRobotics/StepByStep-introduction/11-controller-access-data.py
diff --git a/SoftRobotics/StepByStep-introduction/11-collision-model.py b/SoftRobotics/StepByStep-introduction/12-collision-model.py
similarity index 100%
rename from SoftRobotics/StepByStep-introduction/11-collision-model.py
rename to SoftRobotics/StepByStep-introduction/12-collision-model.py
diff --git a/SoftRobotics/StepByStep-introduction/12-controller-create-objects.py b/SoftRobotics/StepByStep-introduction/13-controller-create-objects.py
similarity index 94%
rename from SoftRobotics/StepByStep-introduction/12-controller-create-objects.py
rename to SoftRobotics/StepByStep-introduction/13-controller-create-objects.py
index 24d103a..e5741b1 100644
--- a/SoftRobotics/StepByStep-introduction/12-controller-create-objects.py
+++ b/SoftRobotics/StepByStep-introduction/13-controller-create-objects.py
@@ -19,17 +19,23 @@ def generateRadius(self):
 	def generatXPos(self):
 		return self.iteration%11 * 10  -170
 
+	def updateCollisionPipeline(self):
+		self.rootNode.removeObject(self.rootNode.collision_pipeline)
+		self.rootNode.addObject("CollisionPipeline", name="collision_pipeline")
+		self.rootNode.collision_pipeline.init()
+
 	def addFallingParticle(self, node):
 		iteration_loc = self.iteration
 		newParticle = node.addChild("ParticleToCollideWith-"+str(iteration_loc))
 		newParticle.addObject("EulerImplicitSolver")
-		newParticle.addObject("CGLinearSolver", iterations=200, tolerance=1e-09, threshold=1e-09)
+		newParticle.addObject("SparseLDLSolver", name="linear_solver", template="CompressedRowSparseMatrixMat3x3d")
 		newParticle.addObject("MechanicalObject", template="Rigid3", name="myParticle", position=[self.generatXPos(), 80, 0,  0,0,0,1], showObject=True)
 		newParticle.addObject("UniformMass", totalMass=1)
 		newParticle.addObject("ConstantForceField", totalForce=[0,-50,0,0,0,0], indices=0)
 		newParticle.addObject("SphereCollisionModel", radius=self.generateRadius(), contactStiffness=100)
 		newParticle.init()
 		self.iteration = iteration_loc +1
+		self.updateCollisionPipeline()
     
 	def removeFallingParticle(self, node):
 		iteration_loc = self.iteration - 1
@@ -41,6 +47,7 @@ def removeFallingParticle(self, node):
 
 			myParticleNode = self.rootNode.removeChild(str(name))
 			self.iteration = iteration_loc
+			self.updateCollisionPipeline()
     
 	def onKeypressedEvent(self, event):
 		key = event["key"]
diff --git a/SoftRobotics/StepByStep-introduction/13-lagrangian-constraints.py b/SoftRobotics/StepByStep-introduction/14-lagrangian-constraints.py
similarity index 100%
rename from SoftRobotics/StepByStep-introduction/13-lagrangian-constraints.py
rename to SoftRobotics/StepByStep-introduction/14-lagrangian-constraints.py
diff --git a/SoftRobotics/StepByStep-introduction/14-final-pneunet.py b/SoftRobotics/StepByStep-introduction/15-final-pneunet.py
similarity index 100%
rename from SoftRobotics/StepByStep-introduction/14-final-pneunet.py
rename to SoftRobotics/StepByStep-introduction/15-final-pneunet.py
diff --git a/SoftRobotics/StepByStep-introduction/6-elastic-finger-units.py b/SoftRobotics/StepByStep-introduction/6-elastic-finger-units.py
new file mode 100644
index 0000000..197fa0d
--- /dev/null
+++ b/SoftRobotics/StepByStep-introduction/6-elastic-finger-units.py
@@ -0,0 +1,37 @@
+def createScene(rootNode):
+
+	from Sofa.Units.Definitions import s, m, mm, N, g, kg, Pa  
+	from Sofa.Units.UnitSystem import MechanicalUnitSystem
+
+	scene_unit = MechanicalUnitSystem(s, m, kg)
+
+	rootNode.name = "RootNode"
+	rootNode.dt = scene_unit(0.01, s)
+	rootNode.gravity = [0, scene_unit(-9.81, N/kg), 0] # Defining gravity along -Y
+
+	rootNode.addObject("DefaultAnimationLoop", name="animation_loop", computeBoundingBox=False)
+	
+	rootNode.addObject("RequiredPlugin", pluginName=["Sofa.Component.StateContainer","Sofa.Component.Mass","Sofa.Component.MechanicalLoad",
+												     "Sofa.Component.LinearSolver.Direct","Sofa.Component.ODESolver.Backward",
+													 "Sofa.Component.IO.Mesh","Sofa.Component.Topology.Container.Dynamic",
+													 "Sofa.Component.SolidMechanics.FEM.Elastic","Sofa.Component.Topology.Container.Constant",
+													 "Sofa.Component.Visual"])
+	rootNode.addObject("VisualStyle", name="visual_options", displayFlags="showForceFields")
+	
+	rootNode.addObject("MeshVTKLoader", name="mesh_loader_coarse", filename="../PneuNets_remeshed.vtk") # Using a VTK file format, thus using MeshVTKLoader
+	
+	################################################
+	# Mechanical representation of the finger object
+	mechanicalModel = rootNode.addChild("Finger")
+	
+	mechanicalModel.addObject("EulerImplicitSolver", name="integration_scheme")
+	mechanicalModel.addObject("SparseLDLSolver", name="linear_solver", template="CompressedRowSparseMatrixMat3x3d")
+	
+    # MeshTopology is a static topology container, i.e. it does not support topology changes (unlike TetrahedronSetTopologyContainer)
+	mechanicalModel.addObject("MeshTopology", name="topology_container", src="@../mesh_loader_coarse" )
+
+	mechanicalModel.addObject("MechanicalObject", template="Vec3", name="state_container", showObject=True) # Define the template as Vec3 for 3D deformable bodies
+	
+	mechanicalModel.addObject("TetrahedronFEMForceField", name="elastic_material_law", template="Vec3", poissonRatio=0.3, youngModulus=scene_unit(100, Pa)) # Define an elastic constitutive law
+	mechanicalModel.addObject("MeshMatrixMass", name="mass", template="Vec3,Vec3", totalMass=scene_unit(500, g)) # Use a mass integrated over the volume
+	################################################
diff --git a/SoftRobotics/StepByStep-introduction/6-rendering-model.py b/SoftRobotics/StepByStep-introduction/7-rendering-model.py
similarity index 100%
rename from SoftRobotics/StepByStep-introduction/6-rendering-model.py
rename to SoftRobotics/StepByStep-introduction/7-rendering-model.py
diff --git a/SoftRobotics/StepByStep-introduction/7-mapping.py b/SoftRobotics/StepByStep-introduction/8-mapping.py
similarity index 100%
rename from SoftRobotics/StepByStep-introduction/7-mapping.py
rename to SoftRobotics/StepByStep-introduction/8-mapping.py
diff --git a/SoftRobotics/StepByStep-introduction/8-different-representations.py b/SoftRobotics/StepByStep-introduction/9-different-representations.py
similarity index 100%
rename from SoftRobotics/StepByStep-introduction/8-different-representations.py
rename to SoftRobotics/StepByStep-introduction/9-different-representations.py