Enhance FEM object integration and update beam parameters

Modify addFEMObject function to return solver and points nodes
Update beam parameters in tutorial scenes (tuto_3, tuto_4, tuto_5)
Refactor FEM object creation in tuto_5 scene
Adjust cable constraint parameters and mapping in tuto_5
Minor code cleanup and parameter naming consistency improvements

examples/python3/useful/header.py

@@ -153,8 +153,8 @@ def addSolverNode(parent_node, name='solverNode', template='CompressedRowSparseM
     return solver_node
 
 
-def addFEMObject(parent_node, path):
-    finger_solver = addSolverNode(parent_node)
+def addFEMObject(parent_node, path, name='FEMFinger'):
+    finger_solver = addSolverNode(parent_node, name=name)
 
     # Load a VTK tetrahedral mesh and expose the resulting topology in the scene .
     loader = finger_solver.addObject('MeshVTKLoader', name='loader', filename=f'{path}finger.vtk',
@@ -188,6 +188,8 @@ def addFEMObject(parent_node, path):
                          showIndices="1")
     fem_points.addObject('BarycentricMapping')
 
+    return finger_solver, fem_points
+
 
 def addMappedPoints(parent_node, name="pointsInFEM", position=None, showObject="1",
                     showIndices="1", femPos="0.0 0 0 15 0 0 30 0 0 45 0 0 60 0 0 66 0 0 81 0.0 0.0"):

tutorial/tuto_scenes/tuto_3.py

@@ -14,7 +14,7 @@
 from useful.params import BeamPhysicsParametersNoInertia, BeamGeometryParameters
 from cosserat.CosseratBase import CosseratBase
 
-geoParams = BeamGeometryParameters(beam_length=30.,  nb_section=2, nb_frames=12, build_collision_model=0)
+geoParams = BeamGeometryParameters(beam_length=30.,  nb_section=32, nb_frames=32, build_collision_model=0)
 physicsParams = BeamPhysicsParametersNoInertia(beam_mass=0.3, young_modulus=1.0e3, poisson_ratio=0.38, beam_radius=1.,
                                                beam_length=30)
 Params = Parameters(beam_geo_params=geoParams, beam_physics_params=physicsParams)

tutorial/tuto_scenes/tuto_4.py

@@ -25,7 +25,8 @@
 geoParams = BeamGeometryParameters(beam_length=30.,
                                    nb_section=_nb_section, nb_frames=_nb_section, build_collision_model=0)
 physicsParams = BeamPhysicsParametersNoInertia(beam_mass=1., young_modulus=1.0e4, poisson_ratio=0.38,
-                                               beam_radius=_beam_radius, beam_length=30)
+                                               beam_radius=_beam_radius, beam_length=_beam_length)
+
 simuParams = SimulationParameters()
 Params = Parameters(beam_geo_params=geoParams, beam_physics_params=physicsParams, simu_params=simuParams)
 

tutorial/tuto_scenes/tuto_5.py

@@ -9,7 +9,7 @@
 __copyright__ = "(c) 2021,Inria"
 __date__ = "October, 26 2021"
 
-from useful.header import addHeader, addSolverNode, Finger
+from useful.header import addHeader, addSolverNode, addFEMObject
 from useful.params import BeamPhysicsParametersNoInertia, BeamGeometryParameters, SimulationParameters
 from useful.params import Parameters
 from cosserat.CosseratBase import CosseratBase
@@ -19,21 +19,21 @@
 import os
 from math import pi
 from controller import FingerController
-from numpy import array
-
 
+_beam_radius = 0.5
+_beam_length = 81.
+_nb_section = 32
+force_null = [0., 0., 0., 0., 0., 0.]  # N
 path = f'{os.path.dirname(os.path.abspath(__file__))}/../../examples/python3/actuators/mesh/'
 
-geoParams = BeamGeometryParameters(init_pos=[0., 0., 0.], beamLength=81., showFramesObject=1,
-                                   nbSection=12, nbFrames=32, buildCollisionModel=0)
-physicsParams = BeamPhysicsParametersNoInertia(beamMass=1., youngModulus=5.e6, poissonRatio=0.4, beamRadius=0.5,
-                                      beamLength=30)
+geoParams = BeamGeometryParameters(beam_length=_beam_length, nb_section=_nb_section, nb_frames=_nb_section)
+physicsParams = BeamPhysicsParametersNoInertia(beam_mass=1., young_modulus=5.e6, poisson_ratio=0.4,
+                                               beam_radius=_beam_radius, beam_length=_beam_length)
 
 simuParams = SimulationParameters()
-Params = Parameters(beamGeoParams=geoParams, beamPhysicsParams=physicsParams, simuParams=simuParams)
+Params = Parameters(beam_geo_params=geoParams, beam_physics_params=physicsParams, simu_params=simuParams)
 
-force_null = [0., 0., 0., 0., 0., 0.]  # N
-femPos = [[0.0, 0, 0], [15, 0, 0], [30, 0, 0], [45, 0, 0], [60, 0, 0], [66, 0, 0], [81, 0.0, 0.0]]
+femPos = [[0.0, 0, 0], [15., 0, 0], [30., 0, 0], [45., 0, 0], [60., 0, 0], [66., 0, 0], [81., 0.0, 0.0]]
 
 
 class ForceController(Sofa.Core.Controller):
@@ -44,7 +44,7 @@ def __init__(self, *args, **kwargs):
         self.force_type = kwargs['force_type']
         self.tip_controller = kwargs['tip_controller']
 
-        self.size = geoParams.nbFrames
+        self.size = geoParams.nb_frames
         self.applyForce = True
         self.forceCoeff = 0.
         self.theta = 0.1
@@ -69,7 +69,7 @@ def compute_force(self):
             for i, v in enumerate(vec):
                 force[0][i] = v
 
-    def compute_orthogonal_force(self):
+    def compute_orthogonal_force(self) -> None:
         position = self.frames.position[self.size]  # get the last rigid of the cosserat frame
         orientation = Quat(position[3], position[4], position[5], position[6])  # get the orientation
         # Calculate the direction of the force in order to remain orthogonal to the x axis of the last frame of the beam.
@@ -80,13 +80,13 @@ def compute_orthogonal_force(self):
             for count in range(3):
                 force[0][count] = vec[count]
 
-    def rotate_force(self):
+    def rotate_force(self) -> None:
         if self.forceCoeff <= 100. * pi:
             with self.tip_controller.position.writeable() as position:
                 last_frame = self.frames.position[self.size]
                 vec = Quat(last_frame[3], last_frame[4], last_frame[5], last_frame[6])  # get the orientation
 
-                vec.rotateFromEuler([self.theta, 0., 0.])  # apply rotation arround x-axis 
+                vec.rotateFromEuler([self.theta, 0., 0.])  # apply rotation around x-axis
                 vec.normalize()
                 for i, v in enumerate(vec):
                     position[0][i + 3] = v
@@ -100,10 +100,10 @@ def onKeypressedEvent(self, event):
 
 
 def createScene(root_node):
-    addHeader(root_node, isConstrained=True)
+    addHeader(root_node, is_constrained=True)
     root_node.gravity = [0, 0., 0.]
 
-    solver_node = addSolverNode(root_node, name="solver_node", isConstrained=True)
+    solver_node = addSolverNode(root_node, name="cable_node", isConstrained=True)
 
     # create cosserat Beam
     cosserat_beam = solver_node.addChild(CosseratBase(parent=solver_node, params=Params))
@@ -112,13 +112,15 @@ def createScene(root_node):
     # Finger node
     femFingerNode = root_node.addChild('femFingerNode')
     """ Add FEM finger to the scene"""
-    finger_node, fem_points_node = Finger(femFingerNode, name="Finger", rotation=array([0.0, 180.0, 0.0]),
-                                       translation=array([-17.5, -12.5, 7.5]), path=path)
+    # finger_node, fem_points_node = Finger(femFingerNode, name="Finger", rotation=array([0.0, 180.0, 0.0]),
+    #                                      translation=array([-17.5, -12.5, 7.5]), path=path)
+
+    finger_node, fem_points_node = addFEMObject(root_node, path=path, name="Finger")
 
     #  This creates a new node in the scene. This node is appended to the finger's node.
     cable_state_node = cosserat_frames_node.addChild('cable_state_node')
 
-    # This creates a MechanicalObject, a componante holding the degree of freedom of our
+    # This creates a MechanicalObject, a component holding the degree of freedom of our
     # mechanical modelling. In the case of a cable it is a set of positions specifying
     # the points where the cable is passing by.
     cable_state = cable_state_node.addObject('MechanicalObject', name="cablePos",
@@ -129,20 +131,19 @@ def createScene(root_node):
     distance_node = cable_state_node.addChild('distance_node')
     fem_points_node.addChild(distance_node)
     distance = distance_node.addObject('MechanicalObject', template='Vec3d', position=femPos,
-                                           name="distancePointsMO", showObject='1', showObjectScale='1')
-
+                                       name="distancePointsMO", showObject='1', showObjectScale='1')
 
     """The controller of the cable is added to the scene"""
     cable_state_node.addObject(FingerController(cosserat_beam.rigidBaseNode.RigidBaseMO,
-                                         cosserat_beam.cosseratCoordinateNode.cosseratCoordinateMO))
+                                                cosserat_beam.cosseratCoordinateNode.cosseratCoordinateMO))
 
     inputCableMO = cable_state.getLinkPath()
     inputFEMCableMO = fem_points_node.getLinkPath()
     outputPointMO = distance.getLinkPath()
     """ This constraint is used to compute the distance between the cable and the fem points"""
     distance_node.addObject('QPSlidingConstraint', name="QPConstraint")
-    distance_node.addObject('DifferenceMultiMapping', name="pointsMulti", input1=inputFEMCableMO, indices="5",
-                                 input2=inputCableMO, output=outputPointMO, direction="@../../FramesMO.position")
+    distance_node.addObject('DifferenceMultiMapping', name="pointsMulti", input1=inputFEMCableMO, indices="6",
+                            input2=inputCableMO, output=outputPointMO, direction="@../../FramesMO.position")
 
     return root_node
     # # this constance force is used only in the case we are doing force_type 1 or 2