Exemplo n.º 1
0
def test_qnorm():
    qi = tq.qeye()
    assert tq.qnorm(qi) == 1
    assert tq.qisunit(qi)
    qi[1] = 0.2
    assert not tq.qisunit(qi)
    # Test norm is sqrt of scalar for multiplication with conjugate.
    # https://en.wikipedia.org/wiki/Quaternion#Conjugation,_the_norm,_and_reciprocal
    for q in quats:
        q_c = tq.qconjugate(q)
        exp_norm = np.sqrt(tq.qmult(q, q_c)[0])
        assert np.allclose(tq.qnorm(q), exp_norm)
def test_qnorm():
    qi = tq.qeye()
    assert tq.qnorm(qi) == 1
    assert tq.qisunit(qi)
    qi[1] = 0.2
    assert not tq.qisunit(qi)
    # Test norm is sqrt of scalar for multiplication with conjugate.
    # https://en.wikipedia.org/wiki/Quaternion#Conjugation,_the_norm,_and_reciprocal
    for q in quats:
        q_c = tq.qconjugate(q)
        exp_norm = np.sqrt(tq.qmult(q, q_c)[0])
        assert np.allclose(tq.qnorm(q), exp_norm)
Exemplo n.º 3
0
def update_function(state: np.ndarray,
                    dx: np.ndarray) -> np.ndarray:
    '''
    update state according to delta x.
    :param state:
    :param dx:
    :return:
    '''
    state[:6] += dx[:6]
    q = euler.euler2quat(state[6], state[7], state[8])
    # r_q = euler.euler2quat(input[])
    # w = input[3:6] * time_interval
    w = dx[6:9]
    r_q = euler.euler2quat(w[0], w[1], w[2])
    r_q = r_q / quaternions.qnorm(r_q)
    # q = q * r_q
    q = quaternions.qmult(q, r_q)
    # q = q.fillpositive
    # q = q.norm()
    q = q / quaternions.qnorm(q)
    state[6:9] = euler.quat2euler(q)

    return state
Exemplo n.º 4
0
def test_qnorm():
    qi = tq.qeye()
    assert tq.qnorm(qi) == 1
    assert tq.qisunit(qi)
    qi[1] = 0.2
    assert not tq.qisunit(qi)
Exemplo n.º 5
0
 def cons_func(x):
     qs = x[len_ts:len_ts + len_qs].reshape(scene_q[1:, :].shape)
     return np.asarray([(np.linalg.norm(tfq.qnorm(q)**2 - 1)) for q in qs])
Exemplo n.º 6
0
def orientationEstimaton():
    #import the data
    filename = "imu/imuRaw1.mat"
    viconFileName = "vicon/viconRot1.mat"
    Ax, Ay, Az, Wx, Wy, Wz, ts = importData(filename)

    #intialize the P estimate covariance matrix (3x3)
    Pk_minus = np.zeros((3, 3))
    Pk_minus[0, 0] = 0.277
    Pk_minus[1, 1] = 0.277
    Pk_minus[2, 2] = 0.4

    #initialize a Q matrix (3x3)
    Q = np.diag(np.ones(3) * .1)

    #intialize state
    xk_minus = np.array([1, 0, 0, 0])

    #matrix for final output
    allEstimates = np.empty((len(Ax), 3))

    #run the measurement model for each of the pieces of data we have
    for i in range(0, len(Ax) - 1):
        epsilon = 5
        c = epsilon * np.eye(3)

        #find the S matrix (3x3)
        S = np.linalg.cholesky((2 * len(Q)) * (Pk_minus + Q + c))

        #create the Wi matrix
        Wi = np.hstack((S, -S))  #3x6

        #convert W to quaternion representation
        Xi = np.empty((6, 4))
        for j in range(0, len(Wi)):
            newQuat = axisAngleToQuat(Wi[j, :])
            Xi[j, :] = quat.qnorm(newQuat)

        #add qk-1 to the Xi
        for j in range(0, len(Xi)):
            if i == 0:
                xk_minusAsQuat = np.array([1, 0, 0, 0])
            else:
                xk_minusAsQuat = axisAngleToQuat(xk_minus)
            newQuat = quat.qmult(xk_minusAsQuat, Xi[j, :])
            Xi[j, :] = quat.qnorm(newQuat)

        #get the process model and convert Xi to Yi
        qDelta = processModel(Wx[i], Wy[i], Wz[i], ts[i + 1] - ts[i])
        Yi = np.empty((6, 4))
        for j in range(0, len(Xi)):
            newQuat = quat.qmult(Xi[j, :], qDelta)
            Yi[j, :] = quat.qnorm(newQuat)
        Yi = np.nan_to_num(Yi)

        #get the priori mean and covariance
        [xk_minus_quat, allErrorsX, averageErrorX] = findQuaternionMean(Xi)
        [n, _] = Xi.shape
        xk_minus = quatToAxisAngle(xk_minus_quat)

        #3x3 matrix in terms of axis angle r vectors
        Pk_minus = 1.0 / (2 * n) * np.dot(
            np.array(allErrorsX - averageErrorX).T,
            np.array(allErrorsX - averageErrorX))
        Pk_minus = np.nan_to_num(Pk_minus)

        #this is where the update model starts
        g = measurementModel(Ax[i], Ay[i], Az[i])
        Zi = np.empty((6, 4))
        for j in range(0, len(Yi)):
            vector = np.nan_to_num(Yi[j, :])
            if (np.array_equal(vector, np.array([0, 0, 0, 0]))):
                inverse = vector
            else:
                inverse = np.nan_to_num(quat.qinverse(vector))
            lastTwo = np.nan_to_num(quat.qmult(g, inverse))
            newQuat = np.nan_to_num(quat.qmult(vector, lastTwo))
            Zi[j, :] = np.nan_to_num(quat.qnorm(newQuat))
        #remove all the nans
        Zi = np.nan_to_num(Zi)

        #find the mean and covariance of Zi
        [zk_minus, allErrorsZ, averageErrorZ] = findQuaternionMean(Zi)

        # 6x6 matrix in terms of axis angle r vectors
        Pzz = 1.0 / (2 * n) * np.dot(
            np.array(allErrorsZ - averageErrorZ).T,
            np.array(allErrorsZ - averageErrorZ))

        #find the innovation vk
        zk_plus = np.array([Ax[i], Ay[i], Az[i]])
        zk_minusVector = quatToAxisAngle(zk_minus)
        vk = zk_plus - zk_minusVector

        #find the expected covariance
        R = np.diag(np.ones(3) * .40)
        Pvv = Pzz + R
        Pvv = np.nan_to_num(Pvv)

        #find Pxz, the cross-correlation matrix
        Pxz = 1.0 / (2 * n) * np.dot(
            np.array(allErrorsX - averageErrorX).T,
            np.array(allErrorsZ - averageErrorZ))
        Pxz = np.nan_to_num(Pxz)

        #find the Kalman gain matix
        Kk = Pxz * np.linalg.inv(Pvv)
        Kk = np.nan_to_num(Kk)

        #find the posteriori mean, which is the updated estimate of the state
        xk = xk_minus + np.dot(Kk, vk)
        xk = np.nan_to_num(xk)

        #find the posteriori variation, which is the updated variation
        Pk = Pk_minus - Kk * Pvv * Kk.T
        Pk = np.nan_to_num(Pk)

        #set the new xk to xk_minus and the new Pk to the Pk_minus
        xk_minus = xk
        Pk_minus = Pk

        #add to a matrix and return
        allEstimates[i] = xk_minus

    #visualize the results
    visualizeResults(allEstimates, viconFileName)

    #create the panorama using my own data
    rotsInMatrix = np.empty((3, 3, len(allEstimates)))
    for est in range(0, len(allEstimates)):
        rot = axisAngletoMat(allEstimates[est])
        rotsInMatrix[:, :, est] = rot
    createPanorama(rotsInMatrix, ts)

    return allEstimates