def test_skywalkerX8_force_x_dir():
control_input = ControlInput()
control_input.throttle = 0.0
t = 0
state = State()
state.vx = 20.0
for j in range(3):
state.pitch = state.pitch + 0.05
state.roll = state.roll + 0.05
state.yaw = state.yaw + 0.05
x_update = np.zeros(11)
constants = SkywalkerX8Constants()
for i in range(0, 11):
control_input.throttle = i * 0.1
prop = IcedSkywalkerX8Properties(control_input)
params = {"prop": prop, "wind": no_wind()}
update = dynamics_kinetmatics_update(t,
x=state.state,
u=control_input.control_input,
params=params)
x_update[i] = update[6]
S_p = constants.propeller_area
C_p = constants.motor_efficiency_fact
k_m = constants.motor_constant
m = constants.mass
K = 2 * m / (AIR_DENSITY * S_p * C_p * k_m**2)
for i in range(0, 10):
throttle_0 = i * 0.1
throttle_1 = (i + 1) * 0.1
assert np.allclose(K * (x_update[i + 1] - x_update[i]),
throttle_1**2 - throttle_0**2)
def test_inertial2body_test_cases():
state1 = State()
state1.roll = np.pi / 4.0
vec1 = np.array([0.0, 0.0, 1.0])
expect1 = np.array([0.0, np.sqrt(2.0) / 2.0, np.sqrt(2.0) / 2.0])
state2 = State()
state2.pitch = np.pi / 4.0
vec2 = np.array([0.0, 0.0, 1.0])
expect2 = np.array([-np.sqrt(2.0) / 2.0, 0.0, np.sqrt(2.0) / 2.0])
state3 = State()
state3.yaw = np.pi / 4.0
vec3 = np.array([1.0, 0.0, 0.0])
expect3 = np.array([np.sqrt(2.0) / 2.0, -np.sqrt(2.0) / 2.0, 0.0])
return [(state1, vec1, expect1), (state2, vec2, expect2),
(state3, vec3, expect3)]
def test_kinematics():
control_input = ControlInput()
prop = FrictionlessBall(control_input)
outputs = [
"x", "y", "z", "roll", "pitch", "yaw", "vx", "vy", "vz", "ang_rate_x",
"ang_rate_y", "ang_rate_z"
]
system = build_nonlin_sys(prop, no_wind(), outputs)
t = np.linspace(0.0, 10, 500, endpoint=True)
state = State()
state.vx = 20.0
state.vy = 1
for i in range(3):
state.roll = 0
state.pitch = 0
state.yaw = 0
if i == 0:
state.ang_rate_x = 0.157079633
state.ang_rate_y = 0
state.ang_rate_z = 0
elif i == 1:
state.ang_rate_x = 0
state.ang_rate_y = 0.157079633
state.ang_rate_z = 0
elif i == 2:
state.ang_rate_x = 0
state.ang_rate_y = 0
state.ang_rate_z = 0.157079633
T, yout = input_output_response(system, t, U=0, X0=state.state)
pos = np.array(yout[:3])
eul_ang = np.array(yout[3:6])
vel_inertial = np.array(
[np.zeros(len(t)),
np.zeros(len(t)),
np.zeros(len(t))])
for j in range(len(vel_inertial[0])):
state.roll = yout[3, j]
state.pitch = yout[4, j]
state.yaw = yout[5, j]
vel = np.array([yout[6, j], yout[7, j], yout[8, j]])
vel_inertial_elem = body2inertial(vel, state)
vel_inertial[0, j] = vel_inertial_elem[0]
vel_inertial[1, j] = vel_inertial_elem[1]
vel_inertial[2, j] = vel_inertial_elem[2]
vx_inertial_expect = 20 * np.ones(len(t))
vy_inertial_expect = 1 * np.ones(len(t))
vz_inertial_expect = GRAVITY_CONST * t
x_expect = 20 * t
y_expect = 1 * t
z_expect = 0.5 * GRAVITY_CONST * t**2
roll_expect = state.ang_rate_x * t
pitch_expect = state.ang_rate_y * t
yaw_expect = state.ang_rate_z * t
assert np.allclose(vx_inertial_expect, vel_inertial[0], atol=7e-3)
assert np.allclose(vy_inertial_expect, vel_inertial[1], atol=5e-3)
assert np.allclose(vz_inertial_expect, vel_inertial[2], atol=8e-3)
assert np.allclose(x_expect, pos[0], atol=8e-2)
assert np.allclose(y_expect, pos[1], atol=5e-2)
assert np.allclose(z_expect, pos[2], atol=7e-2)
assert np.allclose(roll_expect, eul_ang[0], atol=1e-3)
assert np.allclose(pitch_expect, eul_ang[1], atol=1e-3)
assert np.allclose(yaw_expect, eul_ang[2], atol=1e-3)