def system(self): r"""Initialise the GProp_GProps depending on the topological type Notes ----- geom_type could be abstracted with TopoDS... instead of using _topo_type Returns ------- OCC.GProp.GProp_GProps """ self._system = GProp_GProps() if self._topo_type in GlobalProperties.surfacic_types: brepgprop_SurfaceProperties(self.shape, self._system) elif self._topo_type in GlobalProperties.linear_types: brepgprop_LinearProperties(self.shape, self._system) elif self._topo_type in GlobalProperties.volumic_types: brepgprop_VolumeProperties(self.shape, self._system) else: msg = "ShapeType is not linear, surfacic or volumic" logger.error(msg) raise WrongTopologicalType(msg) return self._system
def system(self): self._system = GProp_GProps() # todo, type should be abstracted with TopoDS... _topo_type = self.instance.topo_type if _topo_type == 'face' or _topo_type == 'shell': brepgprop_SurfaceProperties(self.instance, self._system) elif _topo_type == 'edge': brepgprop_LinearProperties(self.instance, self._system) elif _topo_type == 'solid': brepgprop_VolumeProperties(self.instance, self._system) return self._system
def cube_inertia_properties(): """ Compute the inertia properties of a shape """ # Create and display cube print("Creating a cubic box shape (50*50*50)") cube_shape = BRepPrimAPI_MakeBox(50., 50., 50.).Shape() # Compute inertia properties props = GProp_GProps() brepgprop_VolumeProperties(cube_shape, props) # Get inertia properties mass = props.Mass() cog = props.CentreOfMass() matrix_of_inertia = props.MatrixOfInertia() # Display inertia properties print("Cube mass = %s" % mass) cog_x, cog_y, cog_z = cog.Coord() print("Center of mass: x = %f;y = %f;z = %f;" % (cog_x, cog_y, cog_z))
def solid_volume(occsolid): """ This function calculates the volume of the OCCsolid. Parameters ---------- occsolid : OCCsolid The OCCsolid to be analysed. Returns ------- volume : float The volume of the solid. """ props = GProp_GProps() brepgprop_VolumeProperties(occsolid, props) volume = props.Mass() return volume
def compute_inertia_and_center_of_mass(shapes, io=None): """ Compute inertia from a list of Shapes. Returns ------- mass center_of_mass inertia inertia_matrix """ from OCC.GProp import GProp_GProps from OCC.BRepGProp import brepgprop_VolumeProperties from OCC.gp import gp_Ax1, gp_Dir from siconos.mechanics import occ system = GProp_GProps() for shape in shapes: iprops = GProp_GProps() if shape.data is None: if io is not None: shape.data = io._shape.get(shape.shape_name, new_instance=True) else: warn('cannot get shape {0}'.format(shape.shape_name)) return None iishape = shape.data ishape = occ.OccContactShape(iishape).data() # the shape relative displacement occ.occ_move(ishape, list(shape.translation) + list(shape.orientation)) brepgprop_VolumeProperties(iishape, iprops) density = None if hasattr(shape, 'mass') and shape.mass is not None: density = shape.mass / iprops.Mass() elif shape.parameters is not None and hasattr(shape.parameters, 'density'): density = shape.parameters.density #print('shape.parameters.density:', shape.parameters.density) else: density = 1. assert density is not None # print("shape", shape.shape_name) # print('density:', density) # print('iprops.Mass():', iprops.Mass()) system.Add(iprops, density) mass = system.Mass() assert (system.Mass() > 0.) computed_com = system.CentreOfMass() gp_mat = system.MatrixOfInertia() inertia_matrix = np.zeros((3, 3)) for i in range(0, 3): for j in range(0, 3): inertia_matrix[i, j] = gp_mat.Value(i + 1, j + 1) I1 = system.MomentOfInertia(gp_Ax1(computed_com, gp_Dir(1, 0, 0))) I2 = system.MomentOfInertia(gp_Ax1(computed_com, gp_Dir(0, 1, 0))) I3 = system.MomentOfInertia(gp_Ax1(computed_com, gp_Dir(0, 0, 1))) inertia = [I1, I2, I3] center_of_mass = np.array( [computed_com.Coord(1), computed_com.Coord(2), computed_com.Coord(3)]) return mass, center_of_mass, inertia, inertia_matrix
def volume(self): '''returns the volume of a solid ''' prop = GProp_GProps() brepgprop_VolumeProperties(self.shape, prop, self.tolerance) return prop
def calculate_volume(shape): props = GProp_GProps() brepgprop_VolumeProperties(shape, props) return props.Mass()
def centerOfMass(solid): prop = GProp_GProps() brepgprop_VolumeProperties(solid, prop) return prop.CentreOfMass()
def _center_of_mass(shape): Properties = GProp_GProps() brepgprop_VolumeProperties(shape, Properties) return Vector(Properties.CentreOfMass())
def compute_inertia_and_center_of_mass(shapes, io=None): """ Compute inertia from a list of Shapes. """ from OCC.GProp import GProp_GProps from OCC.BRepGProp import brepgprop_VolumeProperties from OCC.gp import gp_Ax1, gp_Dir from siconos.mechanics import occ system = GProp_GProps() for shape in shapes: iprops = GProp_GProps() if shape.data is None: if io is not None: shape.data = io._shape.get(shape.shape_name, new_instance=True) else: warn('cannot get shape {0}'.format(shape.shape_name)) return None iishape = shape.data ishape = occ.OccContactShape(iishape).data() # the shape relative displacement occ.occ_move(ishape, list(shape.translation) + list(shape.orientation)) brepgprop_VolumeProperties(iishape, iprops) density = None if hasattr(shape, 'mass') and shape.mass is not None: density = shape.mass / iprops.Mass() elif shape.parameters is not None and \ hasattr(shape.parameters, 'density'): density = shape.parameters.density #print('shape.parameters.density:', shape.parameters.density) else: density = 1. assert density is not None # print("shape", shape.shape_name) # print('density:', density) # print('iprops.Mass():', iprops.Mass()) system.Add(iprops, density) mass= system.Mass() assert (system.Mass() > 0.) computed_com = system.CentreOfMass() gp_mat= system.MatrixOfInertia() inertia_matrix = np.zeros((3,3)) for i in range(0,3): for j in range(0,3): inertia_matrix[i,j]= gp_mat.Value(i+1,j+1) I1 = system.MomentOfInertia( gp_Ax1(computed_com, gp_Dir(1, 0, 0))) I2 = system.MomentOfInertia( gp_Ax1(computed_com, gp_Dir(0, 1, 0))) I3 = system.MomentOfInertia( gp_Ax1(computed_com, gp_Dir(0, 0, 1))) inertia = [I1, I2, I3] center_of_mass = np.array([computed_com.Coord(1), computed_com.Coord(2), computed_com.Coord(3)]) return mass, center_of_mass, inertia, inertia_matrix
def solid_volume(occ_solid): props = GProp_GProps() brepgprop_VolumeProperties(occ_solid, props) volume = props.Mass() return volume
def compute_inertia_and_center_of_mass(shapes, mass, io=None): """ Compute inertia from a list of Shapes. """ from OCC.GProp import GProp_GProps from OCC.BRepGProp import brepgprop_VolumeProperties from OCC.gp import gp_Ax1, gp_Dir from siconos.mechanics import occ props = GProp_GProps() for shape in shapes: iprops = GProp_GProps() if shape.data is None: if io is not None: shape.data = io._shape.get(shape.shape_name, new_instance=True) else: warn('cannot get shape {0}'.format(shape.shape_name)) return None iishape = shape.data ishape = occ.OccContactShape(iishape).data() # the shape relative displacement occ.occ_move(ishape, list(shape.translation) + list(shape.orientation)) brepgprop_VolumeProperties(iishape, iprops) density = None if hasattr(shape, 'mass') and shape.mass is not None: density = shape.mass / iprops.Mass() elif shape.parameters is not None and \ hasattr(shape.parameters, 'density'): density = shape.parameters.density else: density = 1. assert density is not None props.Add(iprops, density) assert (props.Mass() > 0.) global_density = mass / props.Mass() computed_com = props.CentreOfMass() I1 = global_density * props.MomentOfInertia( gp_Ax1(computed_com, gp_Dir(1, 0, 0))) I2 = global_density * props.MomentOfInertia( gp_Ax1(computed_com, gp_Dir(0, 1, 0))) I3 = global_density * props.MomentOfInertia( gp_Ax1(computed_com, gp_Dir(0, 0, 1))) inertia = [I1, I2, I3] center_of_mass = np.array( [computed_com.Coord(1), computed_com.Coord(2), computed_com.Coord(3)]) return inertia, center_of_mass
from OCC.GProp import GProp_GProps from OCC.BRepGProp import brepgprop_VolumeProperties from math import pi # original implementation with occ backend import siconos.io.mechanics_io siconos.io.mechanics_io.set_implementation('original') siconos.io.mechanics_io.set_backend('occ') # ball shape ball = BRepPrimAPI_MakeSphere(.15).Shape() ball_props = GProp_GProps() brepgprop_VolumeProperties(ball, ball_props) ball_mass = ball_props.Mass() ball_com = ball_props.CentreOfMass() ball_inertia = ball_props.MatrixOfInertia() ball_I1 = ball_props.MomentOfInertia(gp_Ax1(ball_com, gp_Dir(1, 0, 0))) ball_I2 = ball_props.MomentOfInertia(gp_Ax1(ball_com, gp_Dir(0, 1, 0))) ball_I3 = ball_props.MomentOfInertia(gp_Ax1(ball_com, gp_Dir(0, 0, 1))) print 'ball mass:', ball_mass print 'ball center of mass:', (ball_com.Coord(1), ball_com.Coord(2), ball_com.Coord(3)) print 'ball moment of inertia:', (ball_I1, ball_I2, ball_I3) # the ground
PFloop = Construct.translate_topods_from_vector(PFloop.Wire(), Construct.gp_Vec(r, 0, z)) PFface = Construct.make_face(PFloop) ax = gp_Ax1(gp_Pnt(0, 0, 0), gp_Dir(0, 0, 1)) PFcoil.append(BRepPrimAPI_MakeRevol(PFface, ax).Shape()) PFcage = Construct.compound(PFcoil) x3d = Construct.compound([TFcage['wp'], TFcage['case'], PFcage, GScage]) my_renderer = x3dom_renderer.X3DomRenderer() my_renderer.DisplayShape(x3d) prop = GpropsFromShape(TF['case']) print('gprop', prop.volume().Mass()) prop = GProp_GProps() brepgprop_VolumeProperties(TF['case'], prop, 1e-6) print('case volume', prop.Mass()) prop = GProp_GProps() brepgprop_VolumeProperties(TF['wp'], prop, 1e-6) print('wp volume', prop.Mass()) prop = GProp_GProps() brepgprop_VolumeProperties(TFcage['wp'], prop, 1e-6) print('cold mass volume', prop.Mass()) display, start_display = init_display()[:2] display.DisplayColoredShape(TFcage['case'], QC[0]) display.DisplayColoredShape(GScage, QC[1]) display.DisplayColoredShape(PFcage, QC[5]) display.FitAll()