#
# ISC License
#
# Copyright (c) 2016, Autonomous Vehicle Systems Lab, University of Colorado at Boulder
#
# Permission to use, copy, modify, and/or distribute this software for any
# purpose with or without fee is hereby granted, provided that the above
# copyright notice and this permission notice appear in all copies.
#
# THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
# WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
# MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
# ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
# WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
# ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
# OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
#
import matplotlib.pyplot as plt
import numpy as np
import pytest
from Basilisk.architecture import messaging
from Basilisk.fswAlgorithms import mrpSteering # import the module that is to be tested
from Basilisk.utilities import RigidBodyKinematics
from Basilisk.utilities import SimulationBaseClass
from Basilisk.utilities import macros
from Basilisk.utilities import unitTestSupport # general support file with common unit test functions
[docs]@pytest.mark.parametrize("K1", [0.15, 0])
@pytest.mark.parametrize("K3", [1, 0])
@pytest.mark.parametrize("omegaMax", [1.5 * macros.D2R, 0.001 * macros.D2R])
# uncomment this line is this test is to be skipped in the global unit test run, adjust message as needed
# @pytest.mark.skipif(conditionstring)
# uncomment this line if this test has an expected failure, adjust message as needed
# @pytest.mark.xfail() # need to update how the RW states are defined
# provide a unique test method name, starting with test_
def test_mrp_steering_tracking(show_plots, K1, K3, omegaMax):
r"""
**Validation Test Description**
This unit test compares the computed :math:`\pmb\omega_{\mathcal{B}^{\ast}/\mathcal{R}}` and
:math:`\pmb\omega_{\mathcal{B}^{\ast}/\mathcal{R}}'` to truth values computed in the python unit test.
**Test Parameters**
This test checks a set of gains ``K1``, ``K3`` and ``omegaMax`` on a rigid body with no external
torques, and with a fixed input reference attitude message. The commanded rate solution
is evaluated against python computed values at 0s, 0.5s and 1s to within a tolerance of :math:`10^{-12}`.
:param show_plots: flag indicating if plots should be shown.
:param K1: The control gain :math:`K_1`
:param K3: The control gain :math:`K_3`
:param omegaMax: The control gain :math:`\omega_{\text{max}}`
:return: void
"""
[testResults, testMessage] = mrp_steering_tracking(show_plots, K1, K3, omegaMax)
assert testResults < 1, testMessage
def mrp_steering_tracking(show_plots, K1, K3, omegaMax):
# The __tracebackhide__ setting influences pytest showing of tracebacks:
# the mrp_steering_tracking() function will not be shown unless the
# --fulltrace command line option is specified.
__tracebackhide__ = True
testFailCount = 0 # zero unit test result counter
testMessages = [] # create empty list to store test log messages
unitTaskName = "unitTask" # arbitrary name (don't change)
unitProcessName = "TestProcess" # arbitrary name (don't change)
# Create a sim module as an empty container
unitTestSim = SimulationBaseClass.SimBaseClass()
# Create test thread
testProcessRate = macros.sec2nano(0.5) # update process rate update time
testProc = unitTestSim.CreateNewProcess(unitProcessName)
testProc.addTask(unitTestSim.CreateNewTask(unitTaskName, testProcessRate))
# Construct algorithm and associated C++ container
module = mrpSteering.mrpSteering()
module.ModelTag = "mrpSteering"
# Add test module to runtime call list
unitTestSim.AddModelToTask(unitTaskName, module)
# Initialize the test module configuration data
module.K1 = K1
module.K3 = K3
module.omega_max = omegaMax
# Create input message and size it because the regular creator of that message
# is not part of the test.
guidCmdData = messaging.AttGuidMsgPayload() # Create a structure for the input message
sigma_BR = np.array([0.3, -0.5, 0.7])
guidCmdData.sigma_BR = sigma_BR
omega_BR_B = np.array([0.010, -0.020, 0.015])
guidCmdData.omega_BR_B = omega_BR_B
omega_RN_B = np.array([-0.02, -0.01, 0.005])
guidCmdData.omega_RN_B = omega_RN_B
domega_RN_B = np.array([0.0002, 0.0003, 0.0001])
guidCmdData.domega_RN_B = domega_RN_B
guidInMsg = messaging.AttGuidMsg().write(guidCmdData)
# Setup logging on the test module output message so that we get all the writes to it
dataLog = module.rateCmdOutMsg.recorder()
unitTestSim.AddModelToTask(unitTaskName, dataLog)
# connect messages
module.guidInMsg.subscribeTo(guidInMsg)
# Need to call the self-init and cross-init methods
unitTestSim.InitializeSimulation()
# Step the simulation to 3*process rate so 4 total steps including zero
unitTestSim.ConfigureStopTime(macros.sec2nano(1.0)) # seconds to stop simulation
unitTestSim.ExecuteSimulation()
# Compute truth states
omegaAstTrue, omegaAstPTrue = findTrueValues(guidCmdData, module)
# compare the module results to the truth values
accuracy = 1e-12
for i in range(0, len(omegaAstTrue)):
# check a vector values
if not unitTestSupport.isArrayEqual(dataLog.omega_BastR_B[i], omegaAstTrue[i], 3, accuracy):
testFailCount += 1
testMessages.append("FAILED: " + module.ModelTag + " Module failed omega_BastR_B unit test at t="
+ str(dataLog.times()[i] * macros.NANO2SEC) + "sec \n")
# compare the module results to the truth values
accuracy = 1e-12
for i in range(0, len(omegaAstPTrue)):
# check a vector values
if not unitTestSupport.isArrayEqual(dataLog.omegap_BastR_B[i], omegaAstPTrue[i], 3, accuracy):
testFailCount += 1
testMessages.append("FAILED: " + module.ModelTag + " Module failed omegap_BastR_B unit test at t="
+ str(dataLog.times()[i] * macros.NANO2SEC) + "sec \n")
# If the argument provided at commandline "--show_plots" evaluates as true,
# plot all figures
if show_plots:
plt.show()
# print out success message if no error were found
if testFailCount == 0:
print("PASSED: " + module.ModelTag)
# return fail count and join into a single string all messages in the list
# testMessage
return [testFailCount, ''.join(testMessages)]
def findTrueValues(guidCmdData, module):
omegaMax = module.omega_max
sigma = np.asarray(guidCmdData.sigma_BR)
K1 = np.asarray(module.K1)
K3 = np.asarray(module.K3)
Bmat = RigidBodyKinematics.BmatMRP(sigma)
omegaAst = [] #np.asarray([0, 0, 0])
omegaAst_P = []
for i in range(len(sigma)):
steerRate = -1*(2*omegaMax/np.pi)*np.arctan((K1*sigma[i]+K3*sigma[i]*sigma[i]*sigma[i])*np.pi/(2*omegaMax))
omegaAst.append(steerRate)
if 1: #module.ignoreOuterLoopFeedforward: #should be "if not"
sigmaP = 0.25*Bmat.dot(omegaAst)
for i in range(len(sigma)):
omegaAstRate = (K1+3*K3*sigma[i]**2)/(1+((K1*sigma[i]+K3*sigma[i]**3)**2)*(np.pi/(2*omegaMax))**2)*sigmaP[i]
omegaAst_P.append(-omegaAstRate)
else:
omegaAst_P = np.asarray([0, 0, 0])
omegaAst = [omegaAst, omegaAst, omegaAst]
omegaAst_P = [omegaAst_P, omegaAst_P, omegaAst_P]
return omegaAst, omegaAst_P
if __name__ == "__main__":
test_mrp_steering_tracking(False, 0.1, 1.0, 1.0)