def smallestDirection(x,method='inertia',return_size=False):
"""Return the direction of the smallest dimension of a Coords
- `x`: a Coords-like array
- `method`: one of 'inertia' or 'random'
- return_size: if True and `method` is 'inertia', a tuple of a direction
vector and the size along that direction and the cross directions;
else, only return the direction vector.
"""
x = x.reshape(-1,3)
if method == 'inertia':
# The idea is to take the smallest dimension in a coordinate
# system aligned with the global axes.
C,r,Ip,I = x.inertia()
X = x.trl(-C).rot(r)
sizes = X.sizes()
i = sizes.argmin()
# r gives the directions as column vectors!
# TODO: maybe we should change that
N = r[:,i]
if return_size:
return N,sizes[i]
else:
return N
elif method == 'random':
# Take the mean of the normals on randomly created triangles
from plugins.trisurface import TriSurface
n = x.shape[0]
m = 3 * (n // 3)
e = arange(m)
random.shuffle(e)
if n > m:
e = concatenate([e,[0,1,n-1]])
el = e[-3:]
S = TriSurface(x,e.reshape(-1,3))
A,N = S.areaNormals()
ok = where(isnan(N).sum(axis=1) == 0)[0]
N = N[ok]
N = N*N
N = N.mean(axis=0)
N = sqrt(N)
N = normalize(N)
return N
def createShellModel():
"""Create the Finite Element Model.
It is supposed here that the Geometry has been created and is available
as a global variable F.
"""
# Turn the Formex structure into a TriSurface
# This guarantees that element i of the Formex is element i of the TriSurface
S = TriSurface(F)
print "The structure has %s nodes, %s edges and %s faces" % (S.ncoords(),S.nedges(),S.nfaces())
nodes = S.coords
elems = S.elems # the triangles
clear()
draw(F)
# Shell section and material properties
# VALUES SHOULD BE SET CORRECTLY
glass_plate = {
'name': 'glass_plate',
'sectiontype': 'shell',
'thickness': 18,
'material': 'glass',
}
glass = {
'name': 'glass',
'young_modulus': 72000,
'shear_modulus': 26200,
'density': 2.5e-9, # T/mm**3
}
print glass_plate
print glass
glasssection = ElemSection(section=glass_plate,material=glass)
PDB = PropertyDB()
# All elements have same property:
PDB.elemProp(set=arange(len(elems)),section=glasssection,eltype='STRI3')
# Calculate the nodal loads
# Area of triangles
area,normals = S.areaNormals()
print "Area:\n%s" % area
### DEFINE LOAD CASE (ask user) ###
res = askItems([('Glass',True),('Snow',False)])
if not res:
return
step = 0
if res['Glass']:
step += 1
NODLoad = zeros((S.ncoords(),3))
# add the GLASS weight
wgt = 450e-6 # N/mm**2
# Or, calculate weight from density:
# wgt = glass_plate['thickness'] * glass['density'] * 9810
# assemble uniform glass load
for e,a in zip(S.elems,area):
NODLoad[e] += [ 0., 0., - a * wgt / 3 ]
# Put the nodal loads in the properties database
for i,P in enumerate(NODLoad):
PDB.nodeProp(tag=step,set=i,cload=[P[0],P[1],P[2],0.,0.,0.])
if res['Snow']:
step += 1
NODLoad = zeros((S.ncoords(),3))
# add NON UNIFORM SNOW
fn = 'hesperia-nieve.prop'
snowp = fromfile(fn,sep=',')
snow_uniform = 320e-6 # N/mm**2
snow_non_uniform = { 1:333e-6, 2:133e-6, 3:133e-6, 4:266e-6, 5:266e-6, 6:667e-6 }
# assemble non-uniform snow load
for e,a,p in zip(S.elems,area,snowp):
NODLoad[e] += [ 0., 0., - a * snow_non_uniform[p] / 3]
# Put the nodal loads in the properties database
for i,P in enumerate(NODLoad):
PDB.nodeProp(tag=step,set=[i],cload=[P[0],P[1],P[2],0.,0.,0.])
# Get support nodes
botnodes = where(isClose(nodes[:,2], 0.0))[0]
bot = nodes[botnodes].reshape((-1,1,3))
pf.message("There are %s support nodes." % bot.shape[0])
botofs = bot + [ 0.,0.,-0.2]
bbot2 = concatenate([bot,botofs],axis=1)
print bbot2.shape
S = Formex(bbot2)
draw(S)
## np_central_loaded = NodeProperty(3, displacement=[[1,radial_displacement]],coords='cylindrical',coordset=[0,0,0,0,0,1])
## #np_transf = NodeProperty(0,coords='cylindrical',coordset=[0,0,0,0,0,1])
## # Radial movement only
## np_fixed = NodeProperty(1,bound=[0,1,1,0,0,0],coords='cylindrical',coordset=[0,0,0,0,0,1])
# Since we left out the ring beam, we enforce no movement at the botnodes
bc = PDB.nodeProp(set=botnodes,bound=[1,1,1,0,0,0],csys=CoordSystem('C',[0,0,0,0,0,1]))
# And we record the name of the bottom nodes set
botnodeset = Nset(bc.nr)
fe_model = Dict(dict(nodes=nodes,elems=elems,prop=PDB,botnodeset=botnodeset,nsteps=step))
export({'fe_model':fe_model})
smooth()
lights(False)
def createFrameModel():
"""Create the Finite Element Model.
It is supposed here that the Geometry has been created and is available
as a global variable F.
"""
wireframe()
lights(False)
# Turn the Formex structure into a TriSurface
# This guarantees that element i of the Formex is element i of the TriSurface
S = TriSurface(F)
nodes = S.coords
elems = S.elems # the triangles
# Create edges and faces from edges
print "The structure has %s nodes, %s edges and %s faces" % (S.ncoords(),S.nedges(),S.nfaces())
# Create the steel structure
E = Formex(nodes[S.getEdges()])
clear()
draw(E)
# Get the tri elements that are part of a quadrilateral:
prop = F.prop
quadtri = S.getFaceEdges()[prop==6]
nquadtri = quadtri.shape[0]
print "%s triangles are part of quadrilateral faces" % nquadtri
if nquadtri > 0:
# Create triangle definitions of the quadtri faces
tri = Connectivity.tangle(quadtri,S.getEdges())
D = Formex(nodes[tri])
clear()
flatwire()
draw(D,color='yellow')
conn = connections(quadtri)
print conn
# Filter out the single connection edges
internal = [ c[0] for c in conn if len(c[1]) > 1 ]
print "Internal edges in quadrilaterals: %s" % internal
E = Formex(nodes[S.getEdges()],1)
E.prop[internal] = 6
wireframe()
clear()
draw(E)
# Remove internal edges
tubes = S.getEdges()[E.prop != 6]
print "Number of tube elements after removing %s internals: %s" % (len(internal),tubes.shape[0])
D = Formex(nodes[tubes],1)
clear()
draw(D)
# Beam section and material properties
b = 60
h = 100
t = 4
b1 = b-2*t
h1 = h-2*t
A = b*h - b1*h1
print b*h**3
I1 = (b*h**3 - b1*h1**3) / 12
I2 = (h*b**3 - h1*b1**3) / 12
I12 = 0
J = 4 * A**2 / (2*(b+h)/t)
tube = {
'name':'tube',
'cross_section': A,
'moment_inertia_11': I1,
'moment_inertia_22': I2,
'moment_inertia_12': I12,
'torsional_constant': J
}
steel = {
'name':'steel',
'young_modulus' : 206000,
'shear_modulus' : 81500,
'density' : 7.85e-9,
}
print tube
print steel
tubesection = ElemSection(section=tube,material=steel)
# Calculate the nodal loads
# Area of triangles
area,normals = S.areaNormals()
print "Area:\n%s" % area
# compute bar lengths
bars = nodes[tubes]
barV = bars[:,1,:] - bars[:,0,:]
barL = sqrt((barV*barV).sum(axis=-1))
print "Member length:\n%s" % barL
### DEFINE LOAD CASE (ask user) ###
res = askItems([('Steel',True),
('Glass',True),
('Snow',False),
('Solver',None,'select',['Calpy','Abaqus']),
])
if not res:
return
nlc = 0
for lc in [ 'Steel','Glass','Snow' ]:
if res[lc]:
nlc += 1
NODLoad = zeros((nlc,S.ncoords(),3))
nlc = 0
if res['Steel']:
# the STEEL weight
lwgt = steel['density'] * tube['cross_section'] * 9810 # mm/s**2
print "Weight per length %s" % lwgt
# assemble steel weight load
for e,L in zip(tubes,barL):
NODLoad[nlc,e] += [ 0., 0., - L * lwgt / 2 ]
nlc += 1
if res['Glass']:
# the GLASS weight
wgt = 450e-6 # N/mm**2
# assemble uniform glass load
for e,a in zip(S.elems,area):
NODLoad[nlc,e] += [ 0., 0., - a * wgt / 3 ]
nlc += 1
if res['Snow']:
# NON UNIFORM SNOW
fn = 'hesperia-nieve.prop'
snowp = fromfile(fn,sep=',')
snow_uniform = 320e-6 # N/mm**2
snow_non_uniform = { 1:333e-6, 2:133e-6, 3:133e-6, 4:266e-6, 5:266e-6, 6:667e-6 }
# assemble non-uniform snow load
for e,a,p in zip(S.elems,area,snowp):
NODLoad[nlc,e] += [ 0., 0., - a * snow_non_uniform[p] / 3]
nlc += 1
# For Abaqus: put the nodal loads in the properties database
print NODLoad
PDB = PropertyDB()
for lc in range(nlc):
for i,P in enumerate(NODLoad[lc]):
PDB.nodeProp(tag=lc,set=i,cload=[P[0],P[1],P[2],0.,0.,0.])
# Get support nodes
botnodes = where(isClose(nodes[:,2], 0.0))[0]
bot = nodes[botnodes]
pf.message("There are %s support nodes." % bot.shape[0])
# Upper structure
nnodes = nodes.shape[0] # node number offset
ntubes = tubes.shape[0] # element number offset
PDB.elemProp(set=arange(ntubes),section=tubesection,eltype='FRAME3D')
# Create support systems (vertical beams)
bot2 = bot + [ 0.,0.,-200.] # new nodes 200mm below bot
botnodes2 = arange(botnodes.shape[0]) + nnodes # node numbers
nodes = concatenate([nodes,bot2])
supports = column_stack([botnodes,botnodes2])
elems = concatenate([tubes,supports])
## !!!
## THIS SHOULD BE FIXED !!!
supportsection = ElemSection(material=steel,section={
'name':'support',
'cross_section': A,
'moment_inertia_11': I1,
'moment_inertia_22': I2,
'moment_inertia_12': I12,
'torsional_constant': J
})
PDB.elemProp(set=arange(ntubes,elems.shape[0]),section=supportsection,eltype='FRAME3D')
# Finally, the botnodes2 get the support conditions
botnodes = botnodes2
## # Radial movement only
## np_fixed = NodeProperty(1,bound=[0,1,1,0,0,0],coords='cylindrical',coordset=[0,0,0,0,0,1])
## # No movement, since we left out the ring beam
## for i in botnodes:
## NodeProperty(i,bound=[1,1,1,0,0,0],coords='cylindrical',coordset=[0,0,0,0,0,1])
## np_central_loaded = NodeProperty(3, displacement=[[1,radial_displacement]],coords='cylindrical',coordset=[0,0,0,0,0,1])
## #np_transf = NodeProperty(0,coords='cylindrical',coordset=[0,0,0,0,0,1])
# Draw the supports
S = connect([Formex(bot),Formex(bot2)])
draw(S,color='black')
if res['Solver'] == 'Calpy':
fe_model = Dict(dict(solver='Calpy',nodes=nodes,elems=elems,prop=PDB,loads=NODLoad,botnodes=botnodes,nsteps=nlc))
else:
fe_model = Dict(dict(solver='Abaqus',nodes=nodes,elems=elems,prop=PDB,botnodes=botnodes,nsteps=nlc))
export({'fe_model':fe_model})
print "FE model created and exported as 'fe_model'"
def createShellModel():
"""Create the Finite Element Model.
It is supposed here that the Geometry has been created and is available
as a global variable F.
"""
# Turn the Formex structure into a TriSurface
# This guarantees that element i of the Formex is element i of the TriSurface
S = TriSurface(F)
print("The structure has %s nodes, %s edges and %s faces" %
(S.ncoords(), S.nedges(), S.nfaces()))
nodes = S.coords
elems = S.elems # the triangles
clear()
draw(F)
# Shell section and material properties
# VALUES SHOULD BE SET CORRECTLY
glass_plate = {
'name': 'glass_plate',
'sectiontype': 'shell',
'thickness': 18,
'material': 'glass',
}
glass = {
'name': 'glass',
'young_modulus': 72000,
'shear_modulus': 26200,
'density': 2.5e-9, # T/mm**3
}
print(glass_plate)
print(glass)
glasssection = ElemSection(section=glass_plate, material=glass)
PDB = PropertyDB()
# All elements have same property:
PDB.elemProp(set=arange(len(elems)), section=glasssection, eltype='STRI3')
# Calculate the nodal loads
# Area of triangles
area, normals = S.areaNormals()
print("Area:\n%s" % area)
### DEFINE LOAD CASE (ask user) ###
res = askItems([('Glass', True), ('Snow', False)])
if not res:
return
step = 0
if res['Glass']:
step += 1
NODLoad = zeros((S.ncoords(), 3))
# add the GLASS weight
wgt = 450e-6 # N/mm**2
# Or, calculate weight from density:
# wgt = glass_plate['thickness'] * glass['density'] * 9810
# assemble uniform glass load
for e, a in zip(S.elems, area):
NODLoad[e] += [0., 0., -a * wgt / 3]
# Put the nodal loads in the properties database
for i, P in enumerate(NODLoad):
PDB.nodeProp(tag=step, set=i, cload=[P[0], P[1], P[2], 0., 0., 0.])
if res['Snow']:
step += 1
NODLoad = zeros((S.ncoords(), 3))
# add NON UNIFORM SNOW
fn = '../data/hesperia-nieve.prop'
snowp = fromfile(fn, sep=',')
snow_uniform = 320e-6 # N/mm**2
snow_non_uniform = {
1: 333e-6,
2: 133e-6,
3: 133e-6,
4: 266e-6,
5: 266e-6,
6: 667e-6
}
# assemble non-uniform snow load
for e, a, p in zip(S.elems, area, snowp):
NODLoad[e] += [0., 0., -a * snow_non_uniform[p] / 3]
# Put the nodal loads in the properties database
for i, P in enumerate(NODLoad):
PDB.nodeProp(tag=step,
set=[i],
cload=[P[0], P[1], P[2], 0., 0., 0.])
# Get support nodes
botnodes = where(isClose(nodes[:, 2], 0.0))[0]
bot = nodes[botnodes].reshape((-1, 1, 3))
pf.message("There are %s support nodes." % bot.shape[0])
botofs = bot + [0., 0., -0.2]
bbot2 = concatenate([bot, botofs], axis=1)
print(bbot2.shape)
S = Formex(bbot2)
draw(S)
## np_central_loaded = NodeProperty(3, displacement=[[1,radial_displacement]],coords='cylindrical',coordset=[0,0,0,0,0,1])
## #np_transf = NodeProperty(0,coords='cylindrical',coordset=[0,0,0,0,0,1])
## # Radial movement only
## np_fixed = NodeProperty(1,bound=[0,1,1,0,0,0],coords='cylindrical',coordset=[0,0,0,0,0,1])
# Since we left out the ring beam, we enforce no movement at the botnodes
bc = PDB.nodeProp(set=botnodes,
bound=[1, 1, 1, 0, 0, 0],
csys=CoordSystem('C', [0, 0, 0, 0, 0, 1]))
# And we record the name of the bottom nodes set
botnodeset = Nset(bc.nr)
fe_model = Dict(
dict(nodes=nodes,
elems=elems,
prop=PDB,
botnodeset=botnodeset,
nsteps=step))
export({'fe_model': fe_model})
smooth()
lights(False)
def createFrameModel():
"""Create the Finite Element Model.
It is supposed here that the Geometry has been created and is available
as a global variable F.
"""
wireframe()
lights(False)
# Turn the Formex structure into a TriSurface
# This guarantees that element i of the Formex is element i of the TriSurface
S = TriSurface(F)
nodes = S.coords
elems = S.elems # the triangles
# Create edges and faces from edges
print("The structure has %s nodes, %s edges and %s faces" %
(S.ncoords(), S.nedges(), S.nfaces()))
# Remove the edges between to quad triangles
drawNumbers(S.coords)
quadtri = where(S.prop == 6)[0]
nquadtri = quadtri.shape[0]
print("%s triangles are part of quadrilateral faces" % nquadtri)
faces = S.getElemEdges()[quadtri]
cnt, ind, xbin = histogram2(faces.reshape(-1), arange(faces.max() + 1))
rem = where(cnt == 2)[0]
print("Total edges %s" % len(S.edges))
print("Removing %s edges" % len(rem))
edges = S.edges[complement(rem, n=len(S.edges))]
print("Remaining edges %s" % len(edges))
# Create the steel structure
E = Formex(nodes[edges])
clear()
draw(E)
warning("Beware! This script is currently under revision.")
conn = connections(quadtri)
print(conn)
# Filter out the single connection edges
internal = [c[0] for c in conn if len(c[1]) > 1]
print("Internal edges in quadrilaterals: %s" % internal)
E = Formex(nodes[edges], 1)
E.prop[internal] = 6
wireframe()
clear()
draw(E)
# Remove internal edges
tubes = edges[E.prop != 6]
print("Number of tube elements after removing %s internals: %s" %
(len(internal), tubes.shape[0]))
D = Formex(nodes[tubes], 1)
clear()
draw(D)
# Beam section and material properties
b = 60
h = 100
t = 4
b1 = b - 2 * t
h1 = h - 2 * t
A = b * h - b1 * h1
print(b * h**3)
I1 = (b * h**3 - b1 * h1**3) / 12
I2 = (h * b**3 - h1 * b1**3) / 12
I12 = 0
J = 4 * A**2 / (2 * (b + h) / t)
tube = {
'name': 'tube',
'cross_section': A,
'moment_inertia_11': I1,
'moment_inertia_22': I2,
'moment_inertia_12': I12,
'torsional_constant': J
}
steel = {
'name': 'steel',
'young_modulus': 206000,
'shear_modulus': 81500,
'density': 7.85e-9,
}
print(tube)
print(steel)
tubesection = ElemSection(section=tube, material=steel)
# Calculate the nodal loads
# Area of triangles
area, normals = S.areaNormals()
print("Area:\n%s" % area)
# compute bar lengths
bars = nodes[tubes]
barV = bars[:, 1, :] - bars[:, 0, :]
barL = sqrt((barV * barV).sum(axis=-1))
print("Member length:\n%s" % barL)
### DEFINE LOAD CASE (ask user) ###
res = askItems([
_I('Steel', True),
_I('Glass', True),
_I('Snow', False),
_I('Solver', choices=['Calpy', 'Abaqus']),
])
if not res:
return
nlc = 0
for lc in ['Steel', 'Glass', 'Snow']:
if res[lc]:
nlc += 1
NODLoad = zeros((nlc, S.ncoords(), 3))
nlc = 0
if res['Steel']:
# the STEEL weight
lwgt = steel['density'] * tube['cross_section'] * 9810 # mm/s**2
print("Weight per length %s" % lwgt)
# assemble steel weight load
for e, L in zip(tubes, barL):
NODLoad[nlc, e] += [0., 0., -L * lwgt / 2]
nlc += 1
if res['Glass']:
# the GLASS weight
wgt = 450e-6 # N/mm**2
# assemble uniform glass load
for e, a in zip(S.elems, area):
NODLoad[nlc, e] += [0., 0., -a * wgt / 3]
nlc += 1
if res['Snow']:
# NON UNIFORM SNOW
fn = '../data/hesperia-nieve.prop'
snowp = fromfile(fn, sep=',')
snow_uniform = 320e-6 # N/mm**2
snow_non_uniform = {
1: 333e-6,
2: 133e-6,
3: 133e-6,
4: 266e-6,
5: 266e-6,
6: 667e-6
}
# assemble non-uniform snow load
for e, a, p in zip(S.elems, area, snowp):
NODLoad[nlc, e] += [0., 0., -a * snow_non_uniform[p] / 3]
nlc += 1
# For Abaqus: put the nodal loads in the properties database
print(NODLoad)
PDB = PropertyDB()
for lc in range(nlc):
for i, P in enumerate(NODLoad[lc]):
PDB.nodeProp(tag=lc, set=i, cload=[P[0], P[1], P[2], 0., 0., 0.])
# Get support nodes
botnodes = where(isClose(nodes[:, 2], 0.0))[0]
bot = nodes[botnodes]
pf.message("There are %s support nodes." % bot.shape[0])
# Upper structure
nnodes = nodes.shape[0] # node number offset
ntubes = tubes.shape[0] # element number offset
PDB.elemProp(set=arange(ntubes), section=tubesection, eltype='FRAME3D')
# Create support systems (vertical beams)
bot2 = bot + [0., 0., -200.] # new nodes 200mm below bot
botnodes2 = arange(botnodes.shape[0]) + nnodes # node numbers
nodes = concatenate([nodes, bot2])
supports = column_stack([botnodes, botnodes2])
elems = concatenate([tubes, supports])
## !!!
## THIS SHOULD BE FIXED !!!
supportsection = ElemSection(material=steel,
section={
'name': 'support',
'cross_section': A,
'moment_inertia_11': I1,
'moment_inertia_22': I2,
'moment_inertia_12': I12,
'torsional_constant': J
})
PDB.elemProp(set=arange(ntubes, elems.shape[0]),
section=supportsection,
eltype='FRAME3D')
# Finally, the botnodes2 get the support conditions
botnodes = botnodes2
## # Radial movement only
## np_fixed = NodeProperty(1,bound=[0,1,1,0,0,0],coords='cylindrical',coordset=[0,0,0,0,0,1])
## # No movement, since we left out the ring beam
## for i in botnodes:
## NodeProperty(i,bound=[1,1,1,0,0,0],coords='cylindrical',coordset=[0,0,0,0,0,1])
## np_central_loaded = NodeProperty(3, displacement=[[1,radial_displacement]],coords='cylindrical',coordset=[0,0,0,0,0,1])
## #np_transf = NodeProperty(0,coords='cylindrical',coordset=[0,0,0,0,0,1])
# Draw the supports
S = connect([Formex(bot), Formex(bot2)])
draw(S, color='black')
if res['Solver'] == 'Calpy':
fe_model = Dict(
dict(solver='Calpy',
nodes=nodes,
elems=elems,
prop=PDB,
loads=NODLoad,
botnodes=botnodes,
nsteps=nlc))
else:
fe_model = Dict(
dict(solver='Abaqus',
nodes=nodes,
elems=elems,
prop=PDB,
botnodes=botnodes,
nsteps=nlc))
export({'fe_model': fe_model})
print("FE model created and exported as 'fe_model'")