Python CreateFDM.set_aircraft_path方法代码示例

# 需要导入模块: from JSBSim_utils import CreateFDM [as 别名]
# 或者: from JSBSim_utils.CreateFDM import set_aircraft_path [as 别名]
    def test_actuator_rate_from_property(self):
        # Second part of the test.
        # #######################
        #
        # The test is run again but this time, <rate_limit> will be read from a
        # property instead of being read from a value hard coded in the aircraft
        # definition file. It has been reported in the bug 1503 of FlightGear
        # that for such a configuration the <actuator> output is constantly
        # increasing even if the input is null. For this script the <actuator>
        # output is stored in the property fcs/left-aileron-pos-rad. The
        # function ScriptExecution will monitor that property and if it changes
        # then the test is failed.

        tree = et.parse(os.path.join(self.path_to_jsbsim_aircrafts, self.aircraft_name + ".xml"))
        actuator_element = tree.getroot().find("flight_control/channel/actuator//rate_limit/..")
        rate_element = actuator_element.find("rate_limit")
        flight_control_element = tree.getroot().find("flight_control")
        property = et.SubElement(flight_control_element, "property")
        property.text = "fcs/rate-limit-value"
        property.attrib["value"] = rate_element.text
        actuator_element = flight_control_element.find("channel/actuator//rate_limit/..")
        rate_element = actuator_element.find("rate_limit")
        rate_element.attrib["sense"] = "decr"
        rate_element.text = property.text
        new_rate_element = et.SubElement(actuator_element, "rate_limit")
        new_rate_element.attrib["sense"] = "incr"
        new_rate_element.text = rate_element.text

        tree.write(self.sandbox("aircraft", self.aircraft_name, self.aircraft_name + ".xml"))

        fdm = CreateFDM(self.sandbox)
        fdm.set_aircraft_path("aircraft")
        self.ScriptExecution(fdm)
        del fdm

# 需要导入模块: from JSBSim_utils import CreateFDM [as 别名]
# 或者: from JSBSim_utils.CreateFDM import set_aircraft_path [as 别名]
    def testOrbit(self):
        script_name = 'ball_orbit.xml'
        script_path = self.sandbox.path_to_jsbsim_file('scripts', script_name)
        self.AddAccelerometersToAircraft(script_path)

        # The time step is too small in ball_orbit so let's increase it to 0.1s
        # for a quicker run
        tree = et.parse(script_path)
        run_tag = tree.getroot().find('./run')
        run_tag.attrib['dt'] = '0.1'
        tree.write(script_name)

        fdm = CreateFDM(self.sandbox)
        fdm.set_aircraft_path('aircraft')
        fdm.load_script(script_name)
        # Switch the accel on
        fdm['fcs/accelerometer/on'] = 1.0
        fdm.run_ic()

        while fdm.run():
            self.assertAlmostEqual(fdm['fcs/accelerometer/X'], 0.0, delta=1E-8)
            self.assertAlmostEqual(fdm['fcs/accelerometer/Y'], 0.0, delta=1E-8)
            self.assertAlmostEqual(fdm['fcs/accelerometer/Z'], 0.0, delta=1E-8)
            self.assertAlmostEqual(fdm['accelerations/a-pilot-x-ft_sec2'], 0.0,
                                   delta=1E-8)
            self.assertAlmostEqual(fdm['accelerations/a-pilot-y-ft_sec2'], 0.0,
                                   delta=1E-8)
            self.assertAlmostEqual(fdm['accelerations/a-pilot-z-ft_sec2'], 0.0,
                                   delta=1E-8)

        del fdm

# 需要导入模块: from JSBSim_utils import CreateFDM [as 别名]
# 或者: from JSBSim_utils.CreateFDM import set_aircraft_path [as 别名]
    def test_CAS_ic(self):
        script_name = 'Short_S23_3.xml'
        script_path = self.sandbox.path_to_jsbsim_file('scripts', script_name)

        # Add a Pitot angle to the Short S23
        tree, aircraft_name, path_to_jsbsim_aircrafts = CopyAircraftDef(script_path, self.sandbox)
        self.addPitotTube(tree.getroot(), 5.0)
        tree.write(self.sandbox('aircraft', aircraft_name,
                                aircraft_name+'.xml'))

        # Read the CAS specified in the IC file
        tree = et.parse(script_path)
        use_element = tree.getroot().find('use')
        IC_file = use_element.attrib['initialize']
        tree = et.parse(os.path.join(path_to_jsbsim_aircrafts,
                                     append_xml(IC_file)))
        vc_tag = tree.getroot().find('./vc')
        VCAS = float(vc_tag.text)
        if 'unit' in vc_tag.attrib and vc_tag.attrib['unit'] == 'FT/SEC':
            VCAS /= 1.68781  # Converts in kts

        # Run the IC and check that the model is initialized correctly
        fdm = CreateFDM(self.sandbox)
        fdm.set_aircraft_path('aircraft')
        fdm.load_script(script_path)
        fdm.run_ic()

        self.assertAlmostEqual(fdm['ic/vc-kts'], VCAS, delta=1E-7)
        self.assertAlmostEqual(fdm['velocities/vc-kts'], VCAS, delta=1E-7)

# 需要导入模块: from JSBSim_utils import CreateFDM [as 别名]
# 或者: from JSBSim_utils.CreateFDM import set_aircraft_path [as 别名]
    def Compare(self, section):
        # Rerun the script with the modified aircraft definition
        self.sandbox.delete_csv_files()
        fdm = CreateFDM(self.sandbox)
        # We need to tell JSBSim that the aircraft definition is located in the
        # directory build/.../aircraft
        fdm.set_aircraft_path('aircraft')
        fdm.set_output_directive(self.sandbox.path_to_jsbsim_file('tests',
                                                                  'output.xml'))
        fdm.load_script(self.script)
        fdm['simulation/randomseed'] = 0.0

        fdm.run_ic()
        ExecuteUntil(fdm, 50.0)

        mod = pd.read_csv('output.csv', index_col=0)

        # Check the data are matching i.e. the time steps are the same between
        # the two data sets and that the output data are also the same.
        self.assertTrue(isDataMatching(self.ref, mod))

        # Whether the data is read from the aircraft definition file or from an
        # external file, the results shall be exactly identical. Hence the
        # precision set to 0.0.
        diff = FindDifferences(self.ref, mod, 0.0)
        self.assertEqual(len(diff), 0,
                         msg='\nTesting section "'+section+'"\n'+diff.to_string())

# 需要导入模块: from JSBSim_utils import CreateFDM [as 别名]
# 或者: from JSBSim_utils.CreateFDM import set_aircraft_path [as 别名]
    def test_actuator_rate_from_property(self):
        # Second part of the test.
        # #######################
        #
        # The test is run again but this time, <rate_limit> will be read from a
        # property instead of being read from a value hard coded in the
        # aircraft definition file. It has been reported in the bug 1503 of
        # FlightGear that for such a configuration the <actuator> output is
        # constantly increasing even if the input is null. For this script the
        # <actuator> output is stored in the property
        # fcs/left-aileron-pos-rad. The function ScriptExecution will monitor
        # that property and if it changes then the test is failed.

        tree = et.parse(os.path.join(self.path_to_jsbsim_aircrafts, self.aircraft_name+'.xml'))
        actuator_element = tree.getroot().find('flight_control/channel/actuator//rate_limit/..')
        rate_element = actuator_element.find('rate_limit')
        flight_control_element = tree.getroot().find('flight_control')
        property = et.SubElement(flight_control_element, 'property')
        property.text = 'fcs/rate-limit-value'
        property.attrib['value'] = rate_element.text
        actuator_element = flight_control_element.find('channel/actuator//rate_limit/..')
        rate_element = actuator_element.find('rate_limit')
        rate_element.attrib['sense'] = 'decr'
        rate_element.text = property.text
        new_rate_element = et.SubElement(actuator_element, 'rate_limit')
        new_rate_element.attrib['sense'] = 'incr'
        new_rate_element.text = rate_element.text

        tree.write(self.sandbox('aircraft', self.aircraft_name, self.aircraft_name+'.xml'))

        fdm = CreateFDM(self.sandbox)
        fdm.set_aircraft_path('aircraft')
        self.ScriptExecution(fdm)
        del fdm

# 需要导入模块: from JSBSim_utils import CreateFDM [as 别名]
# 或者: from JSBSim_utils.CreateFDM import set_aircraft_path [as 别名]
    def test_fuel_tanks_inertia(self):
        script_path = self.sandbox.path_to_jsbsim_file('scripts', 'c1722.xml')

        # The aircraft c172x does not contain an <inertia_factor> tag so we
        # need to add one.
        tree, aircraft_name, b = CopyAircraftDef(script_path, self.sandbox)
        tank_tag = tree.getroot().find('propulsion/tank')
        inertia_factor = et.SubElement(tank_tag, 'inertia_factor')
        inertia_factor.text = '1.0'
        tree.write(self.sandbox('aircraft', aircraft_name,
                                aircraft_name+'.xml'))

        fdm = CreateFDM(self.sandbox)
        fdm.set_aircraft_path('aircraft')
        fdm.load_script(script_path)
        fdm.run_ic()

        contents0 = fdm['propulsion/tank/contents-lbs']
        ixx0 = fdm['propulsion/tank/local-ixx-slug_ft2']
        iyy0 = fdm['propulsion/tank/local-iyy-slug_ft2']
        izz0 = fdm['propulsion/tank/local-izz-slug_ft2']

        # Remove half of the tank contents and check that the inertias are
        # updated accordingly
        fdm['propulsion/tank/contents-lbs'] = 0.5*contents0
        contents = fdm['propulsion/tank/contents-lbs']
        ixx = fdm['propulsion/tank/local-ixx-slug_ft2']
        iyy = fdm['propulsion/tank/local-iyy-slug_ft2']
        izz = fdm['propulsion/tank/local-izz-slug_ft2']

        self.assertAlmostEqual(contents, 0.5*contents0, delta=1E-7,
                               msg="The tank content (%f lbs) should be %f lbs" % (contents, 0.5*contents0))
        self.assertAlmostEqual(ixx, 0.5*ixx0, delta=1E-7,
                               msg="The tank inertia Ixx (%f slug*ft^2) should be %f slug*ft^2" % (ixx, 0.5*ixx0))
        self.assertAlmostEqual(iyy, 0.5*iyy0, delta=1E-7,
                               msg="The tank inertia Iyy (%f slug*ft^2) should be %f slug*ft^2" % (iyy, 0.5*iyy0))
        self.assertAlmostEqual(izz, 0.5*izz0, delta=1E-7,
                               msg="The tank inertia Izz (%f slug*ft^2) should be %f slug*ft^2" % (izz, 0.5*izz0))

        # Execute the script and check that the fuel inertias have been updated
        # along with the consumption.
        ExecuteUntil(fdm, 200.0)

        contents = fdm['propulsion/tank/contents-lbs']
        ixx = fdm['propulsion/tank/local-ixx-slug_ft2']
        iyy = fdm['propulsion/tank/local-iyy-slug_ft2']
        izz = fdm['propulsion/tank/local-izz-slug_ft2']

        contents_ratio = contents / contents0
        ixx_ratio = ixx / ixx0
        iyy_ratio = iyy / iyy0
        izz_ratio = izz / izz0

        self.assertAlmostEqual(contents_ratio, ixx_ratio, delta=1E-7,
                               msg="Ixx does not vary as the tank content does\nIxx ratio=%f\nContents ratio=%f" % (ixx_ratio, contents_ratio))
        self.assertAlmostEqual(contents_ratio, iyy_ratio, delta=1E-7,
                               msg="Iyy does not vary as the tank content does\nIyy ratio=%f\nContents ratio=%f" % (iyy_ratio, contents_ratio))
        self.assertAlmostEqual(contents_ratio, izz_ratio, delta=1E-7,
                               msg="Izz does not vary as the tank content does\nIzz ratio=%f\nContents ratio=%f" % (izz_ratio, contents_ratio))

# 需要导入模块: from JSBSim_utils import CreateFDM [as 别名]
# 或者: from JSBSim_utils.CreateFDM import set_aircraft_path [as 别名]
    def test_pitot_angle(self):
        script_name = 'ball_chute.xml'
        script_path = self.sandbox.path_to_jsbsim_file('scripts', script_name)

        # Add a Pitot angle to the Cessna 172
        tree, aircraft_name, path_to_jsbsim_aircrafts = CopyAircraftDef(script_path, self.sandbox)
        root = tree.getroot()
        pitot_angle_deg = 5.0
        self.addPitotTube(root, 5.0)
        contact_tag = root.find('./ground_reactions/contact')
        contact_tag.attrib['type'] = 'STRUCTURE'
        tree.write(self.sandbox('aircraft', aircraft_name,
                                aircraft_name+'.xml'))

        fdm = CreateFDM(self.sandbox)
        fdm.set_aircraft_path('aircraft')
        fdm.load_model('ball')
        pitot_angle = pitot_angle_deg * math.pi / 180.
        weight = fdm['inertia/weight-lbs']
        spring_tag = contact_tag.find('./spring_coeff')
        spring_coeff = float(spring_tag.text)
        print "Weight=%d Spring=%d" % (weight, spring_coeff)
        fdm['ic/h-sl-ft'] = weight / spring_coeff
        fdm['forces/hold-down'] = 1.0
        fdm.run_ic()

        ExecuteUntil(fdm, 10.)

        for i in xrange(36):
            for j in xrange(-9, 10):
                angle = math.pi * i / 18.0
                angle2 = math.pi * j / 18.0
                ca2 = math.cos(angle2)
                fdm['atmosphere/wind-north-fps'] = 10. * math.cos(angle) * ca2
                fdm['atmosphere/wind-east-fps'] = 10. * math.sin(angle) * ca2
                fdm['atmosphere/wind-down-fps'] = 10. * math.sin(angle2)
                fdm.run()

                vg = fdm['velocities/vg-fps']
                self.assertAlmostEqual(vg, 0.0, delta=1E-7)

                vt = fdm['velocities/vt-fps']
                self.assertAlmostEqual(vt, 10., delta=1E-7)

                mach = vt / fdm['atmosphere/a-fps']
                P = fdm['atmosphere/P-psf']
                pt = P * math.pow(1+0.2*mach*mach, 3.5)
                psl = fdm['atmosphere/P-sl-psf']
                rhosl = fdm['atmosphere/rho-sl-slugs_ft3']
                A = math.pow((pt-P)/psl+1.0, 1.0/3.5)
                alpha = fdm['aero/alpha-rad']
                beta = fdm['aero/beta-rad']
                vc = math.sqrt(7.0*psl/rhosl*(A-1.0))*math.cos(alpha+pitot_angle)*math.cos(beta)

                self.assertAlmostEqual(fdm['velocities/vc-kts'],
                                       max(0.0, vc) / 1.68781, delta=1E-7)

# 需要导入模块: from JSBSim_utils import CreateFDM [as 别名]
# 或者: from JSBSim_utils.CreateFDM import set_aircraft_path [as 别名]
def CheckRateLimit(script_path, input_prop, output_prop, incr_limit, decr_limit):
    fdm = CreateFDM(sandbox)
    fdm.set_aircraft_path('aircraft')

    ScriptExecution(fdm, script_path, 1.0)

    fdm.set_property_value(input_prop, 1.0)

    CheckRateValue(fdm, output_prop, incr_limit)

    fdm.set_property_value(input_prop, 0.0)
    CheckRateValue(fdm, output_prop, decr_limit)

# 需要导入模块: from JSBSim_utils import CreateFDM [as 别名]
# 或者: from JSBSim_utils.CreateFDM import set_aircraft_path [as 别名]
    def testSteadyFlight(self):
        script_name = 'c1722.xml'
        script_path = self.sandbox.path_to_jsbsim_file('scripts', script_name)
        self.AddAccelerometersToAircraft(script_path)

        fdm = CreateFDM(self.sandbox)
        fdm.set_aircraft_path('aircraft')
        fdm.load_script(script_path)
        # Switch the accel on
        fdm['fcs/accelerometer/on'] = 1.0
        # Use the standard gravity (i.e. GM/r^2)
        fdm['simulation/gravity-model'] = 0
        # Select an orientation such that frame transformations simplify
        fdm['ic/psi-true-rad'] = 0.0
        fdm.run_ic()

        ExecuteUntil(fdm, 0.1)

        fdm['simulation/do_simple_trim'] = 1

        r = fdm['position/radius-to-vehicle-ft']
        pitch = fdm['attitude/theta-rad']
        roll = fdm['attitude/phi-rad']
        latitude = fdm['position/lat-gc-rad']
        g = fdm['accelerations/gravity-ft_sec2']
        omega = 0.00007292115  # Earth rotation rate in rad/sec
        fc = r * math.cos(latitude) * omega * omega  # Centrifugal force

        uvw = np.array(fdm.get_propagate().get_uvw().T)[0]
        Omega = omega * np.array([math.cos(pitch - latitude),
                                  math.sin(pitch - latitude) * math.sin(roll),
                                  math.sin(pitch - latitude) * math.cos(roll)])

        # Compute the acceleration measured by the accelerometer as the sum of
        # the gravity and the centrifugal and Coriolis forces.
        fa_yz = (fc * math.cos(latitude - pitch) - g * math.cos(pitch))
        fa = np.array([(fc * math.sin(latitude - pitch) + g * math.sin(pitch)),
                       fa_yz * math.sin(roll),
                       fa_yz * math.cos(roll)]) + np.cross(2.0*Omega, uvw)

        # After the trim we are close to the equilibrium but there remains a
        # small residual that we have to take the bias into account
        fax = fa[0] + fdm['accelerations/udot-ft_sec2']
        fay = fa[1] + fdm['accelerations/vdot-ft_sec2']
        faz = fa[2] + fdm['accelerations/wdot-ft_sec2']

        # Deltas are relaxed because the tolerances of the trimming algorithm
        # are quite relaxed themselves.
        self.assertAlmostEqual(fdm['fcs/accelerometer/X'], fax, delta=1E-6)
        self.assertAlmostEqual(fdm['fcs/accelerometer/Y'], fay, delta=1E-4)
        self.assertAlmostEqual(fdm['fcs/accelerometer/Z'], faz, delta=1E-5)

        del fdm

# 需要导入模块: from JSBSim_utils import CreateFDM [as 别名]
# 或者: from JSBSim_utils.CreateFDM import set_aircraft_path [as 别名]
    def test_grain_tanks_content(self):
        script_path = self.sandbox.path_to_jsbsim_file('scripts', 'J2460.xml')
        tree, aircraft_name, b = CopyAircraftDef(script_path, self.sandbox)

        id = 0
        for tank in tree.getroot().findall('propulsion/tank'):
            grain_config = tank.find('grain_config')
            if grain_config and grain_config.attrib['type'] == 'CYLINDRICAL':
                break
            ++id

        capacity = float(tank.find('capacity').text)
        tank.find('contents').text = str(0.5*capacity)
        tree.write(self.sandbox('aircraft', aircraft_name,
                                aircraft_name+'.xml'))

        radius_tag = tank.find('radius')
        radius = float(radius_tag.text)
        if 'unit' in radius_tag.attrib and radius_tag.attrib['unit'] == 'IN':
            radius /= 12.0

        bore_diameter_tag = tank.find('grain_config/bore_diameter')
        bore_radius = 0.5*float(bore_diameter_tag.text)
        if 'unit' in bore_diameter_tag.attrib and bore_diameter_tag.attrib['unit'] == 'IN':
            bore_radius /= 12.0

        fdm = CreateFDM(self.sandbox)
        fdm.set_aircraft_path('aircraft')
        fdm.load_script(script_path)
        fdm.run_ic()

        tank_name = 'propulsion/tank[%g]' % (id,)

        self.assertAlmostEqual(fdm[tank_name+'/contents-lbs'], 0.5*capacity)
        fdm['propulsion/tank/contents-lbs'] = capacity
        mass = capacity / 32.174049  # Converting lbs to slugs
        ixx = 0.5 * mass * (radius * radius + bore_radius*bore_radius)
        self.assertAlmostEqual(fdm[tank_name+'local-ixx-slug_ft2'], ixx)

        del fdm

        tank.find('contents').text = '0.0'
        tree.write(self.sandbox('aircraft', aircraft_name,
                                aircraft_name+'.xml'))

        fdm = CreateFDM(self.sandbox)
        fdm.set_aircraft_path('aircraft')
        fdm.load_script(script_path)
        fdm.run_ic()

        self.assertAlmostEqual(fdm[tank_name+'/contents-lbs'], 0.0)
        fdm['propulsion/tank/contents-lbs'] = capacity

# 需要导入模块: from JSBSim_utils import CreateFDM [as 别名]
# 或者: from JSBSim_utils.CreateFDM import set_aircraft_path [as 别名]
    def steerType(self, hasSteerPosDeg, hasSteeringAngle, hasCastered):
        self.tree.write(self.sandbox('aircraft', self.aircraft_name,
                                     self.aircraft_name+'.xml'))

        fdm = CreateFDM(self.sandbox)
        fdm.set_aircraft_path('aircraft')
        fdm.load_script(self.script_path)
        fdm.run_ic()
        pm = fdm.get_property_manager()
        self.assertTrue(pm.hasNode('fcs/steer-pos-deg') == hasSteerPosDeg)
        self.assertTrue(pm.hasNode('gear/unit/steering-angle-deg')
                        == hasSteeringAngle)
        self.assertTrue(pm.hasNode('gear/unit/castered') == hasCastered)

        return fdm

# 需要导入模块: from JSBSim_utils import CreateFDM [as 别名]
# 或者: from JSBSim_utils.CreateFDM import set_aircraft_path [as 别名]
    def test_moment(self):
        script_path = self.sandbox.path_to_jsbsim_file('scripts',
                                                       'ball_chute.xml')
        tree, aircraft_name, aircraft_path = CopyAircraftDef(script_path,
                                                             self.sandbox)
        extReact_element = tree.getroot().find('external_reactions')
        moment_element = et.SubElement(extReact_element, 'moment')
        moment_element.attrib['name'] = 'parachute'
        moment_element.attrib['frame'] = 'WIND'
        direction_element = et.SubElement(moment_element, 'direction')
        x_element = et.SubElement(direction_element, 'x')
        x_element.text = '0.2'
        y_element = et.SubElement(direction_element, 'y')
        y_element.text = '0.0'
        z_element = et.SubElement(direction_element, 'z')
        z_element.text = '-1.5'

        tree.write(self.sandbox('aircraft', aircraft_name,
                                aircraft_name+'.xml'))

        fdm = CreateFDM(self.sandbox)
        fdm.set_aircraft_path('aircraft')
        fdm.load_script(script_path)
        fdm.run_ic()

        mDir = np.array([0.2, 0.0, -1.5])
        mDir /= np.linalg.norm(mDir)
        self.assertAlmostEqual(fdm['external_reactions/parachute/l'], mDir[0])
        self.assertAlmostEqual(fdm['external_reactions/parachute/m'], mDir[1])
        self.assertAlmostEqual(fdm['external_reactions/parachute/n'], mDir[2])

        fdm['external_reactions/parachute/magnitude-lbsft'] = -3.5

        while fdm.run():
            Tw2b = fdm.get_auxiliary().get_Tw2b()
            mag = fdm['aero/qbar-psf'] * fdm['fcs/parachute_reef_pos_norm']*20.0
            f = Tw2b * np.mat([-1.0, 0.0, 0.0]).T * mag
            self.assertAlmostEqual(fdm['forces/fbx-external-lbs'], f[0, 0])
            self.assertAlmostEqual(fdm['forces/fby-external-lbs'], f[1, 0])
            self.assertAlmostEqual(fdm['forces/fbz-external-lbs'], f[2, 0])

            m = -3.5 * Tw2b * np.mat(mDir).T
            fm = np.cross(self.getLeverArm(fdm,'parachute'),
                          np.array([f[0,0], f[1,0], f[2, 0]]))
            self.assertAlmostEqual(fdm['moments/l-external-lbsft'], m[0, 0] + fm[0])
            self.assertAlmostEqual(fdm['moments/m-external-lbsft'], m[1, 0] + fm[1])
            self.assertAlmostEqual(fdm['moments/n-external-lbsft'], m[2, 0] + fm[2])

# 需要导入模块: from JSBSim_utils import CreateFDM [as 别名]
# 或者: from JSBSim_utils.CreateFDM import set_aircraft_path [as 别名]
    def CheckRateLimit(self, input_prop, output_prop, incr_limit, decr_limit):
        fdm = CreateFDM(self.sandbox)
        fdm.set_aircraft_path('aircraft')

        self.ScriptExecution(fdm, 1.0)

        fdm[input_prop] = 1.0

        self.CheckRateValue(fdm, output_prop, incr_limit)

        fdm[input_prop] = 0.0
        self.CheckRateValue(fdm, output_prop, decr_limit)

        # Because JSBSim internals use static pointers, we cannot rely on
        # Python garbage collector to decide when the FDM is destroyed
        # otherwise we can get dangling pointers.
        del fdm

# 需要导入模块: from JSBSim_utils import CreateFDM [as 别名]
# 或者: from JSBSim_utils.CreateFDM import set_aircraft_path [as 别名]
    def testSpinningBodyOnOrbit(self):
        script_name = 'ball_orbit.xml'
        script_path = self.sandbox.path_to_jsbsim_file('scripts', script_name)
        self.AddAccelerometersToAircraft(script_path)

        fdm = CreateFDM(self.sandbox)
        fdm.set_aircraft_path('aircraft')
        fdm.load_model('ball')
        # Offset the CG along Y (by 30")
        fdm.set_property_value('inertia/pointmass-weight-lbs[1]', 50.0)

        aircraft_path = self.sandbox.elude(self.sandbox.path_to_jsbsim_file('aircraft', 'ball'))
        fdm.load_ic(os.path.join(aircraft_path, 'reset00.xml'), False)
        # Switch the accel on
        fdm.set_property_value('fcs/accelerometer/on', 1.0)
        # Set the orientation such that the spinning axis is Z.
        fdm.set_property_value('ic/phi-rad', 0.5*math.pi)

        # Set the angular velocities to 0.0 in the ECEF frame. The angular
        # velocity R_{inertial} will therefore be equal to the Earth rotation
        # rate 7.292115E-5 rad/sec
        fdm.set_property_value('ic/p-rad_sec', 0.0)
        fdm.set_property_value('ic/q-rad_sec', 0.0)
        fdm.set_property_value('ic/r-rad_sec', 0.0)
        fdm.run_ic()

        fax = fdm.get_property_value('fcs/accelerometer/X')
        fay = fdm.get_property_value('fcs/accelerometer/Y')
        faz = fdm.get_property_value('fcs/accelerometer/Z')
        cgy_ft = fdm.get_property_value('inertia/cg-y-in') / 12.
        omega = 0.00007292115 # Earth rotation rate in rad/sec

        self.assertAlmostEqual(fdm.get_property_value('accelerations/a-pilot-x-ft_sec2'),
                               fax, delta=1E-8)
        self.assertAlmostEqual(fdm.get_property_value('accelerations/a-pilot-y-ft_sec2'),
                               fay, delta=1E-8)
        self.assertAlmostEqual(fdm.get_property_value('accelerations/a-pilot-z-ft_sec2'),
                               faz, delta=1E-8)

        # Acceleration along X should be zero
        self.assertAlmostEqual(fax, 0.0, delta=1E-8)
        # Acceleration along Y should be equal to r*omega^2
        self.assertAlmostEqual(fay / (cgy_ft * omega * omega), 1.0, delta=1E-7)
        # Acceleration along Z should be zero
        self.assertAlmostEqual(faz, 0.0, delta=1E-8)

# 需要导入模块: from JSBSim_utils import CreateFDM [as 别名]
# 或者: from JSBSim_utils.CreateFDM import set_aircraft_path [as 别名]
    def testSteadyFlight(self):
        script_name = 'c1722.xml'
        script_path = self.sandbox.path_to_jsbsim_file('scripts', script_name)
        self.AddAccelerometersToAircraft(script_path)

        fdm = CreateFDM(self.sandbox)
        fdm.set_aircraft_path('aircraft')
        fdm.load_script(script_path)
        # Switch the accel on
        fdm.set_property_value('fcs/accelerometer/on', 1.0)
        # Use the standard gravity (i.e. GM/r^2)
        fdm.set_property_value('simulation/gravity-model', 0)
        # Simplifies the transformation to compare the accelerometer with the
        # gravity
        fdm.set_property_value('ic/psi-true-rad', 0.0)
        fdm.run_ic()

        while fdm.get_property_value('simulation/sim-time-sec') <= 0.5:
            fdm.run()

        fdm.set_property_value('simulation/do_simple_trim', 1)
        ax = fdm.get_property_value('accelerations/udot-ft_sec2')
        ay = fdm.get_property_value('accelerations/vdot-ft_sec2')
        az = fdm.get_property_value('accelerations/wdot-ft_sec2')
        g = fdm.get_property_value('accelerations/gravity-ft_sec2')
        theta = fdm.get_property_value('attitude/theta-rad')

        # There is a lag of one time step between the computations of the
        # accelerations and the update of the accelerometer
        fdm.run()
        fax = fdm.get_property_value('fcs/accelerometer/X')
        fay = fdm.get_property_value('fcs/accelerometer/Y')
        faz = fdm.get_property_value('fcs/accelerometer/Z')

        fax -= ax
        fay -= ay
        faz -= az

        # Deltas are relaxed because the tolerances of the trimming algorithm
        # are quite relaxed themselves.
        self.assertAlmostEqual(faz / (g * math.cos(theta)), -1.0, delta=1E-5)
        self.assertAlmostEqual(fax / (g * math.sin(theta)), 1.0, delta=1E-5)
        self.assertAlmostEqual(math.sqrt(fax*fax+fay*fay+faz*faz)/g, 1.0, delta=1E-6)

        del fdm