def test_write_simple_JSBSimAircraft(self):
rocket = rdoc.Rocket("Rocket")
stage0 = rdoc.Stage("Sustainer")
body = rdoc.Bodytube("body", 1, 0.2, diameter=0.33)
engine = rdoc.Engine("test engine")
engine.manufacturer = "Open Aerospace"
engine.length = 0.1
engine.diameter = 0.2
engine.Isp = 169
engine.m_prop = 1.0
engine.thrust_avg = 1000
body.components = [engine]
stage0.components = [
rdoc.Nosecone(rdoc.Noseshape.VONKARMAN, 1, 0.2, 1.0), body
]
rocket.stages = [stage0]
rocket.aero_properties['CD'] = [(0.1, 0.8), (0.5, 0.6), (1.0, 0.8)]
str_file = writers.JSBSimAircraft.dump(rocket)
# print(str_file)
# smoke test
self.assertGreater(len(str_file), 150)
def test_rocket_length_sum(self):
stage0 = document.Stage("Booster")
stage0.components = [
document.Nosecone("", 1, 0.7, 1.2),
document.Bodytube("body", 0, 1),
document.Bodytube("body", 24.1, 1),
]
stage1 = document.Stage("Booster")
stage1.components = [
document.Bodytube("body", 4.87, 1),
document.Fin('fin', 1, 1, 1, sweepangle=45.0, mass=0.1),
]
rocket = document.Rocket("Rocket")
rocket.stages = [stage0, stage1]
self.assertAlmostEqual(rocket.length, 5.2)
def test_stage_mass_sum(self):
stage0 = document.Stage("Booster")
stage0.components = [
document.Nosecone(document.Noseshape.CONE, 0, 0.7, 1.4),
document.Bodytube("body", 0, 1),
document.Bodytube("body", 24.1, 1),
]
self.assertEqual(24.8, stage0.mass)
def test_spec_a_rocket(self):
rocket = document.Rocket("Rocket")
stage0 = document.Stage("Booster")
stage0.components = [
document.Nosecone(document.Noseshape.VONKARMAN, 1, 0.7, 1.2),
document.Bodytube("body", 1.2, 0.5),
]
rocket.stages = [stage0]
def __init__(self, Isp, thrust, impulse, CD):
"""Take variables as input, build a rocket"""
# Create an engine document
engine = document.Engine('Motor')
# Set our design
engine.Isp = Isp
engine.thrust_avg = thrust
engine.I_total = impulse
# volume of propellent needed
prop_volume = engine.m_prop / self.prop_density
# Solve for the radius/length of the fuel grain (assume solid, end burning)
engine.diameter = 2 * (prop_volume / (2 * self.LD * pi))**(1 / 3.0)
engine.length = engine.diameter * self.LD
# Add a nose
nose = document.Nosecone(
document.Noseshape.TANGENT_OGIVE, # Shape
1.0, # shape_parameter
3.5, # mass
engine.diameter * self.Nose_LD, # Length
diameter=engine.diameter,
)
# Payload section
payload = document.Bodytube(
"Payload", # Name
3.5, # mass
0.33, # length, fixed
diameter=engine.diameter,
)
# Body section the size of the engine
body = document.Bodytube(
"Body", # Name
20.0, # mass
engine.length,
diameter=engine.diameter,
)
body.components = [engine]
# Rocket:
rocket = document.Rocket("Rocket")
rocket.aero_properties['CD'] = CD
stage0 = document.Stage("Sustainer")
stage0.components = [nose, payload, body]
rocket.stages = [stage0]
self.rocket = rocket
def test_write_document_smoke(self):
rocket = rdoc.Rocket("Rocket")
stage0 = rdoc.Stage("Sustainer")
stage0.components = [
rdoc.Nosecone(rdoc.Noseshape.VONKARMAN, 1, 0.2, 1.0),
rdoc.Bodytube("body", 1, 0.2),
]
rocket.stages = [stage0]
str_file = writers.Document().dump(rocket)
# print("Output:")
# print(str_file)
self.assertGreater(len(str_file), 10)
def test_write_simple_svg(self):
rocket = rdoc.Rocket("Rocket")
stage0 = rdoc.Stage("Sustainer")
stage0.components = [
rdoc.Nosecone(rdoc.Noseshape.VONKARMAN, 1, 0.2, 1.0, diameter=0.2),
rdoc.Bodytube("body", 1, 1.2, diameter=0.2),
]
rocket.stages = [stage0]
str_file = writers.SVG.dump(rocket)
# print("Output:")
# print(str_file)
# with open("testdraw.svg", "w") as testwrite:
# testwrite.write(str_file)
self.assertGreater(len(str_file), 10)
def test_rocket_length_sum_0(self):
# just rocket
rocket = document.Rocket("Rocket")
self.assertEqual(rocket.length, 0)
# rocket and a stage
stage0 = document.Stage("sustainer")
rocket.stages = [stage0]
self.assertEqual(rocket.length, 0)
# zero length components in rocket
stage0.components = [
document.Nosecone("", 1, 0.7, 0),
document.Bodytube("body", 0, 0),
document.Bodytube("body", 24.1, 0)
]
self.assertEqual(rocket.length, 0)
def load(self, filename):
"""Read an OpenRocket file"""
zf = ZipFile(filename)
root = ET.fromstring(zf.read(zf.namelist()[0]))
self.or_version = root.attrib['version']
# Walk tree, there should be a 'rocket' and 'simulation tags'. We only
# care about 'rocket'. After that there is a little metadata and then
# components.
for element in root:
if element.tag == 'rocket':
# We found a rocket! Create a document
ordoc = rdoc.Rocket("Imported OpenRocket File") # default name
for orkrocket in element:
if orkrocket.tag == 'name':
# This rocket has a name
ordoc.name = orkrocket.text
if orkrocket.tag == 'subcomponents':
# This rocket has stages
for orkstage in orkrocket:
if orkstage.tag == 'stage':
# Create a stage, default name is stage number
stage = rdoc.Stage("stage {0}".format(len(ordoc.stages)))
for stage_parts in orkstage:
if stage_parts.tag == 'name':
stage.name = stage_parts.text
if stage_parts.tag == 'subcomponents':
# Recurse down through all components
stage.components = [part for part in self._subcomponent_walk(stage_parts)]
# Append to rocket
ordoc.stages.append(stage)
return ordoc
def test_stage_name_slug(self):
# replace spaces with dashes
c = document.Stage("Stage-0")
self.assertEqual(c.name_slug, "stage-0")
def rocket():
# parametric thrust curve:
peak_thrust = random.uniform(3000, 4200)
delay_time = random.uniform(0.5, 30.0)
min_thrust = random.uniform(0.5, 1.0)
growth_rate = random.uniform(1.01, 2.5)
engine = document.Engine("Motor")
engine.m_prop = 70.0 # kg
engine.diameter = 0.28
engine.length = 1.5
isp = 244
max_impulse = engine.m_prop * isp * 9.8
thrust = 1.0
thrustcurve = []
itot = 0
for i in range(500):
t = i * 0.1
if t > delay_time:
thrust = min_thrust * growth_rate**(t - delay_time)
if thrust > 1.0:
thrust = 1.0
thrust_N = thrust * peak_thrust
# compute Total impulse
if i > 0:
x = thrustcurve[-1]['t']
x_1 = t
f_x = thrustcurve[-1]['thrust']
f_x1 = thrust_N
itot += ((x_1 - x) * (f_x1 + f_x)) / 2.0
thrustcurve.append({'t': t, 'thrust': thrust_N})
# When we exceed our impulse budget quit
if itot > max_impulse:
break
engine.thrustcurve = thrustcurve
body.components = [engine]
# Rocket:
rocket = document.Rocket("Rocket")
rocket.aero_properties['CD'] = [
(0.010, 0.699865),
(0.200, 0.580362),
(0.300, 0.586504),
(0.400, 0.595115),
(0.500, 0.606208),
(0.600, 0.619801),
(0.700, 0.635912),
(0.800, 0.654567),
(0.900, 0.675792),
(0.950, 0.681607),
(1.000, 0.688266),
(1.050, 0.725044),
(1.100, 0.722610),
(1.200, 0.657679),
(1.300, 0.595412),
(1.400, 0.572275),
(1.500, 0.550839),
(1.600, 0.530843),
(1.700, 0.512105),
(1.800, 0.494492),
(1.900, 0.477901),
(2.000, 0.462252),
]
stage0 = document.Stage("Sustainer")
stage0.components = [nose, payload, body]
rocket.stages = [stage0]
return rocket