import numpy as np
import openmdao.api as om
[docs]
class NonIntersectingThickness(om.ExplicitComponent):
"""
Create a constraint so the thickness of the spar does not intersect
itself in the center of the spar. Basically, the thickness must be less
than or equal to the radius.
parameters
----------
thickness[ny-1] : numpy array
Thickness of each element of the FEM spar.
radius[ny-1] : numpy array
Radius of each element of the FEM spar.
Returns
-------
thickness_intersects[ny-1] : numpy array
If all the values are negative, each element does not intersect itself.
If a value is positive, then the thickness within the hollow spar
intersects itself and presents an impossible design.
Add a constraint as
`OASProblem.add_constraint('thickness_intersects', upper=0.)`
"""
def initialize(self):
self.options.declare("surface", types=dict)
def setup(self):
self.surface = surface = self.options["surface"]
self.ny = surface["mesh"].shape[1]
self.add_input("thickness", val=np.zeros((self.ny - 1)), units="m")
self.add_input("radius", val=np.zeros((self.ny - 1)), units="m")
self.add_output("thickness_intersects", val=np.zeros((self.ny - 1)), units="m")
arange = np.arange(self.ny - 1)
self.declare_partials("thickness_intersects", "thickness", rows=arange, cols=arange, val=1.0)
self.declare_partials("thickness_intersects", "radius", rows=arange, cols=arange, val=-1.0)
def compute(self, inputs, outputs):
outputs["thickness_intersects"] = inputs["thickness"] - inputs["radius"]