-
The Unscented Kalman Filter for StateEstimation
Colin McManus
Autonomous Space Robotics LabUniversity of Toronto Institute for
Aerospace Studies
UTIAS
Presented at the Simultaneous Localization and Mapping (SLAM)
Workshop
May 29th, 2010
Colin McManus (UTIAS) The UKF for State Estimation May 29th,
2010 1 / 28
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UTIASOutline
Problem Statement
The Extended Kalman Filter (EKF)OverviewExampleSummary
The Unscented Kalman Filter (UKF)OverviewExampleUKF
variantsSummary
EKF and UKF Comparison Summary
Questions
Colin McManus (UTIAS) The UKF for State Estimation May 29th,
2010 2 / 28
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Problem Statement
Defining termsStereoCamera GPS
Lidar
State:p(xk|u1:k, y1:k) N
(xk, Pk
)
Motion model:
xk = h (xk1,uk,wk) , wk N (0,Qk)Sensor model:
yk = g (xk,nk) , nk N (0,Rk)
Colin McManus (UTIAS) The UKF for State Estimation May 29th,
2010 3 / 28
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UTIAS
Problem Statement
Defining termsStereoCamera GPS
Lidar
State:p(xk|u1:k, y1:k) N
(xk, Pk
)Motion model:
xk = h (xk1,uk,wk) , wk N (0,Qk)
Sensor model:
yk = g (xk,nk) , nk N (0,Rk)
Colin McManus (UTIAS) The UKF for State Estimation May 29th,
2010 3 / 28
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UTIAS
Problem Statement
Defining termsStereoCamera GPS
Lidar
State:p(xk|u1:k, y1:k) N
(xk, Pk
)Motion model:
xk = h (xk1,uk,wk) , wk N (0,Qk)Sensor model:
yk = g (xk,nk) , nk N (0,Rk)Colin McManus (UTIAS) The UKF for
State Estimation May 29th, 2010 3 / 28
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UTIAS
Problem Statement
GoalGoal at time-step k:
{xk1, Pk1,uk, yk} {xk, Pk}
Measurement update (correction step):
xk = xk + Kk (yk yk)Pk = Pk KkU
Tk
I xk : Predicted stateI Pk : Predicted covarianceI Kk : Kalman
gainI yk : Predicted measurementI Uk : Cross-covariance term
Colin McManus (UTIAS) The UKF for State Estimation May 29th,
2010 4 / 28
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UTIAS
Problem Statement
GoalGoal at time-step k:
{xk1, Pk1,uk, yk} {xk, Pk}
Measurement update (correction step):
xk = xk + Kk (yk yk)Pk = Pk KkU
Tk
I xk : Predicted stateI Pk : Predicted covarianceI Kk : Kalman
gainI yk : Predicted measurementI Uk : Cross-covariance term
Colin McManus (UTIAS) The UKF for State Estimation May 29th,
2010 4 / 28
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UTIAS
The Extended Kalman Filter (EKF) Overview
Extended Kalman Filter
I Nonlinear extension to the famous Kalman FilterI EKF uses a
first-order Taylor series expansion of the motion and
observation models with respect to the current state
estimate
I Prediction step:
xk = h(xk1,uk, 0)Pk = Hx,kPk1H
Tx,k + Hw,kQkH
Tw,k
where
Hx,k :=h(xk1,uk,wk)
xk1
xk1,uk,0
, Hw,k :=h(xk1,uk,wk)
wk
xk1,uk,0
.
Colin McManus (UTIAS) The UKF for State Estimation May 29th,
2010 5 / 28
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UTIAS
The Extended Kalman Filter (EKF) Overview
Extended Kalman Filter
I Nonlinear extension to the famous Kalman FilterI EKF uses a
first-order Taylor series expansion of the motion and
observation models with respect to the current state estimateI
Prediction step:
xk = h(xk1,uk, 0)Pk = Hx,kPk1H
Tx,k + Hw,kQkH
Tw,k
where
Hx,k :=h(xk1,uk,wk)
xk1
xk1,uk,0
, Hw,k :=h(xk1,uk,wk)
wk
xk1,uk,0
.
Colin McManus (UTIAS) The UKF for State Estimation May 29th,
2010 5 / 28
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UTIAS
The Extended Kalman Filter (EKF) Example
Example
I Consider a simple example with a quadratic nonlinearity,
h (xk1, uk, wk) = x2k1 + wk
Colin McManus (UTIAS) The UKF for State Estimation May 29th,
2010 6 / 28
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UTIAS
The Extended Kalman Filter (EKF) Example
Example
(Loading)
Colin McManus (UTIAS) The UKF for State Estimation May 29th,
2010 7 / 28
ekf3.wmvMedia File (video/x-ms-wmv)
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The Extended Kalman Filter (EKF) Summary
Strengths and weaknesses
Strengths:I Computationally inexpensive
Weaknesses:I For highly nonlinear problems, the EKF is known to
encounter
issues with both accuracy and stability (Julier et al. ,1995;
Wanand van der Merwe, 2000)
I When analytical Jacobians are not available, numerical
Jacobiansare required
Colin McManus (UTIAS) The UKF for State Estimation May 29th,
2010 8 / 28
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The Unscented Kalman Filter (UKF) Overview
Unscented Kalman Filter
I Introduced by Julier et al. (1995) as a derivative-free
alternative tothe EKF
I UKF uses a weighted set of deterministically sampled
pointscalled sigma-points, which are passed through the
nonlinearityand are used to approximate the statistics of the
distribution
I Unscented Transformation is accurate to at least third-order
forGaussian systems
Colin McManus (UTIAS) The UKF for State Estimation May 29th,
2010 9 / 28
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UTIAS
The Unscented Kalman Filter (UKF) Overview
Unscented Kalman Filter
Image taken from van der Merwe and Wan (2001).
Colin McManus (UTIAS) The UKF for State Estimation May 29th,
2010 10 / 28
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UTIAS
The Unscented Kalman Filter (UKF) Overview
The Unscented Transformation
A set of 2N + 1 sigma-points is computed from the prior
density,N(
xk1, Pk1)
, according to
SST := Pk1 (Cholesky decomposition)X0 := xk1Xi := xk1 +
N + coliS
i = 1 . . . NXi+N := xk1 N + coliS
where N = dim(xk1).
Xi = h (Xi) , for i = 0 . . . 2N
Colin McManus (UTIAS) The UKF for State Estimation May 29th,
2010 11 / 28
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The Unscented Kalman Filter (UKF) Overview
The Unscented Transformation
The mean and covariance are computed as follows:
xk =1
N +
(X0 +
1
2
2Ni=1
Xi
),
Pk =1
N +
((X0 x
) (X0 x
)T+
1
2
2Ni=1
(Xi x
) (Xi x
)T).
I Why this deterministic sampling scheme?I Consider the
expectation of the prior mean plus a disturbance:
xk = E [h (xk1 + x)] , x N(
0, Pk1)
Colin McManus (UTIAS) The UKF for State Estimation May 29th,
2010 12 / 28
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UTIAS
The Unscented Kalman Filter (UKF) Overview
The Unscented Transformation
The mean and covariance are computed as follows:
xk =1
N +
(X0 +
1
2
2Ni=1
Xi
),
Pk =1
N +
((X0 x
) (X0 x
)T+
1
2
2Ni=1
(Xi x
) (Xi x
)T).
I Why this deterministic sampling scheme?
I Consider the expectation of the prior mean plus a
disturbance:
xk = E [h (xk1 + x)] , x N(
0, Pk1)
Colin McManus (UTIAS) The UKF for State Estimation May 29th,
2010 12 / 28
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UTIAS
The Unscented Kalman Filter (UKF) Overview
The Unscented Transformation
The mean and covariance are computed as follows:
xk =1
N +
(X0 +
1
2
2Ni=1
Xi
),
Pk =1
N +
((X0 x
) (X0 x
)T+
1
2
2Ni=1
(Xi x
) (Xi x
)T).
I Why this deterministic sampling scheme?I Consider the
expectation of the prior mean plus a disturbance:
xk = E [h (xk1 + x)] , x N(
0, Pk1)
Colin McManus (UTIAS) The UKF for State Estimation May 29th,
2010 12 / 28
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UTIAS
The Unscented Kalman Filter (UKF) Overview
Analytical Linearization
xk = E [h (xk1 + x)]
= h (xk1) + E[
Dxh +D2xh
2!+
D3xh3!
+D4xh
4!+ . . .
]where,
Dnxhn!
=1
n!
(Ni=1
xn
xn
)nh (x)
x=xk1
Colin McManus (UTIAS) The UKF for State Estimation May 29th,
2010 13 / 28
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UTIAS
The Unscented Kalman Filter (UKF) Overview
Analytical LinearizationBy symmetry, odd-moments are zero,
xk = h (xk1) + E[
D2xh2!
+D4xh
4!+ . . .
]
The second-order term is given by,
E[
D2xh2!
]=
(TE
[xxT
]
2!
)h
x=xk1
=
(T Pk1
2!
)h
x=xk1
Resulting in the following
xk = h (xk1) +
(T Pk1
2!
)h
x=xk1
+ E[
D4xh4!
+ . . .
]
Colin McManus (UTIAS) The UKF for State Estimation May 29th,
2010 14 / 28
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UTIAS
The Unscented Kalman Filter (UKF) Overview
Analytical LinearizationBy symmetry, odd-moments are zero,
xk = h (xk1) + E[
D2xh2!
+D4xh
4!+ . . .
]The second-order term is given by,
E[
D2xh2!
]=
(TE
[xxT
]
2!
)h
x=xk1
=
(T Pk1
2!
)h
x=xk1
Resulting in the following
xk = h (xk1) +
(T Pk1
2!
)h
x=xk1
+ E[
D4xh4!
+ . . .
]
Colin McManus (UTIAS) The UKF for State Estimation May 29th,
2010 14 / 28
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UTIAS
The Unscented Kalman Filter (UKF) Overview
Analytical LinearizationBy symmetry, odd-moments are zero,
xk = h (xk1) + E[
D2xh2!
+D4xh
4!+ . . .
]The second-order term is given by,
E[
D2xh2!
]=
(TE
[xxT
]
2!
)h
x=xk1
=
(T Pk1
2!
)h
x=xk1
Resulting in the following
xk = h (xk1) +
(T Pk1
2!
)h
x=xk1
+ E[
D4xh4!
+ . . .
]
Colin McManus (UTIAS) The UKF for State Estimation May 29th,
2010 14 / 28
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UTIAS
The Unscented Kalman Filter (UKF) Overview
Statistical Linearization
We define some samples according to
Xi := xk1 + ii = 0 . . . 2NXi = h (Xi)
where N = dim (xk1). Now we calculate the weighted
sigma-pointexpectations and compare with the true mean
Colin McManus (UTIAS) The UKF for State Estimation May 29th,
2010 15 / 28
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UTIAS
The Unscented Kalman Filter (UKF) Overview
Statistical Linearization
xk = h (xk1) +1
2(N + )
2Ni=1
(Dih +
D2ih2!
+D3ih
3!+
D4ih4!
+ . . .
)
The second-order term is given by
D2ih2!
=
(TiTi
2!
)hx=xk1
Recall
E[
D2xh2!
]=
(TE
[xxT
]
2!
)h
x=xk1
=
(T Pk1
2!
)h
x=xk1
Colin McManus (UTIAS) The UKF for State Estimation May 29th,
2010 16 / 28
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UTIAS
The Unscented Kalman Filter (UKF) Overview
Statistical Linearization
xk = h (xk1) +1
2(N + )
2Ni=1
(Dih +
D2ih2!
+D3ih
3!+
D4ih4!
+ . . .
)
The second-order term is given by
D2ih2!
=
(TiTi
2!
)hx=xk1
Recall
E[
D2xh2!
]=
(TE
[xxT
]
2!
)h
x=xk1
=
(T Pk1
2!
)h
x=xk1
Colin McManus (UTIAS) The UKF for State Estimation May 29th,
2010 16 / 28
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UTIAS
The Unscented Kalman Filter (UKF) Overview
Statistical Linearization
xk = h (xk1) +1
2(N + )
2Ni=1
(Dih +
D2ih2!
+D3ih
3!+
D4ih4!
+ . . .
)
The second-order term is given by
D2ih2!
=
(TiTi
2!
)hx=xk1
Recall
E[
D2xh2!
]=
(TE
[xxT
]
2!
)h
x=xk1
=
(T Pk1
2!
)h
x=xk1
Colin McManus (UTIAS) The UKF for State Estimation May 29th,
2010 16 / 28
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The Unscented Kalman Filter (UKF) Overview
Statistical Linearization
We let i := N + coliS, where SST = Pk1, which gives
xk = h (xk1) +
(T Pk1
2!
)h
x=xk1
+1
2(N + )
2Ni=1
(D4ih
4!+ . . .
)
Compare above with analytical linearization
xk = h (xk1) +
(T Pk1
2!
)h
x=xk1
+ E[
D4xh4!
+ . . .
]
Colin McManus (UTIAS) The UKF for State Estimation May 29th,
2010 17 / 28
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UTIAS
The Unscented Kalman Filter (UKF) Overview
Statistical Linearization
We let i := N + coliS, where SST = Pk1, which gives
xk = h (xk1) +
(T Pk1
2!
)h
x=xk1
+1
2(N + )
2Ni=1
(D4ih
4!+ . . .
)
Compare above with analytical linearization
xk = h (xk1) +
(T Pk1
2!
)h
x=xk1
+ E[
D4xh4!
+ . . .
]
Colin McManus (UTIAS) The UKF for State Estimation May 29th,
2010 17 / 28
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UTIAS
The Unscented Kalman Filter (UKF) Example
Example
(Loading)
Colin McManus (UTIAS) The UKF for State Estimation May 29th,
2010 18 / 28
ukf3.wmvMedia File (video/x-ms-wmv)
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UTIAS
The Unscented Kalman Filter (UKF) UKF variants
Augmented UKF
xk = h (xk1,uk,wk) , wk N (0,Qk)yk = g (xk,nk) , nk N (0,Rk)
I Completely general case, both the prior belief, the process
noiseand measurement noise have uncertainty so these are
stackedtogether in the following way:
z :=
xk100
, Y :=Pk1 0 00 Qk 0
0 0 Rk
I Let N := dim (x), P := dim (Qk), M := dim (Rk)I Number of
sigma-points: 2(N + P +M) + 1
Colin McManus (UTIAS) The UKF for State Estimation May 29th,
2010 19 / 28
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UTIAS
The Unscented Kalman Filter (UKF) UKF variants
Augmented UKF
xk = h (xk1,uk,wk) , wk N (0,Qk)yk = g (xk,nk) , nk N (0,Rk)
I Completely general case, both the prior belief, the process
noiseand measurement noise have uncertainty so these are
stackedtogether in the following way:
z :=
xk100
, Y :=Pk1 0 00 Qk 0
0 0 Rk
I Let N := dim (x), P := dim (Qk), M := dim (Rk)I Number of
sigma-points: 2(N + P +M) + 1
Colin McManus (UTIAS) The UKF for State Estimation May 29th,
2010 19 / 28
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UTIAS
The Unscented Kalman Filter (UKF) UKF variants
Augmented UKF
xk = h (xk1,uk,wk) , wk N (0,Qk)yk = g (xk,nk) , nk N (0,Rk)
I Completely general case, both the prior belief, the process
noiseand measurement noise have uncertainty so these are
stackedtogether in the following way:
z :=
xk100
, Y :=Pk1 0 00 Qk 0
0 0 Rk
I Let N := dim (x), P := dim (Qk), M := dim (Rk)I Number of
sigma-points: 2(N + P +M) + 1
Colin McManus (UTIAS) The UKF for State Estimation May 29th,
2010 19 / 28
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UTIAS
The Unscented Kalman Filter (UKF) UKF variants
Additive noiseI If our motion and observation model are given
by
xk = h (xk1,uk) + wk, wk N (0,Qk)yk = g (xk) + nk, nk N
(0,Rk)
I Only 2N + 1 sigma-points are required!
z := xk1, Y := Pk1
I Must re-draw sigma-points from {xk , Pk } for the correction
step
(lose odd-moment information)I Alternatively, we can use 2(N + P
) + 1 sigma-points for the
correction step and avoid re-drawing (incorporate
Qk intosigma-points)
Colin McManus (UTIAS) The UKF for State Estimation May 29th,
2010 20 / 28
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UTIAS
The Unscented Kalman Filter (UKF) UKF variants
Additive noise
I If our motion and observation model are given by
xk = h (xk1,uk,wk) , wk N (0,Qk)yk = g (xk) + nk, nk N
(0,Rk)
I Only 2(N + P ) + 1 sigma-points are required
z :=[
xk10
], Y :=
[Pk1 0
0 Qk
]
Colin McManus (UTIAS) The UKF for State Estimation May 29th,
2010 21 / 28
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The Unscented Kalman Filter (UKF) UKF variants
Other efficiency improvements
I Spherical-simplex sigma-points (Julier et al., 2003)I Used a
set of N + 2 sigma-points, which were chosen to minimize
the third-order moments (accurate to second-order)I Reduced
sigma-point UKF (Quine, 2006)
I Used a minimal set of N + 1 sigma-points (accurate
tosecond-order)
I Square-root Unscented Kalman Filter (van der Merwe and
Wan,2001)
I Efficient square-root form that avoids refactorizing the
statecovariance at the prediction step and reduces computational
costrequired to compute the Kalman gain
I Present additional benefits in terms of numerical stability
andensures that the state covariance is always
positive-definite
Colin McManus (UTIAS) The UKF for State Estimation May 29th,
2010 22 / 28
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UTIAS
The Unscented Kalman Filter (UKF) UKF variants
Other efficiency improvements
I Spherical-simplex sigma-points (Julier et al., 2003)I Used a
set of N + 2 sigma-points, which were chosen to minimize
the third-order moments (accurate to second-order)
I Reduced sigma-point UKF (Quine, 2006)I Used a minimal set of N
+ 1 sigma-points (accurate to
second-order)I Square-root Unscented Kalman Filter (van der
Merwe and Wan,
2001)I Efficient square-root form that avoids refactorizing the
state
covariance at the prediction step and reduces computational
costrequired to compute the Kalman gain
I Present additional benefits in terms of numerical stability
andensures that the state covariance is always
positive-definite
Colin McManus (UTIAS) The UKF for State Estimation May 29th,
2010 22 / 28
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UTIAS
The Unscented Kalman Filter (UKF) UKF variants
Other efficiency improvements
I Spherical-simplex sigma-points (Julier et al., 2003)I Used a
set of N + 2 sigma-points, which were chosen to minimize
the third-order moments (accurate to second-order)I Reduced
sigma-point UKF (Quine, 2006)
I Used a minimal set of N + 1 sigma-points (accurate
tosecond-order)
I Square-root Unscented Kalman Filter (van der Merwe and
Wan,2001)
I Efficient square-root form that avoids refactorizing the
statecovariance at the prediction step and reduces computational
costrequired to compute the Kalman gain
I Present additional benefits in terms of numerical stability
andensures that the state covariance is always
positive-definite
Colin McManus (UTIAS) The UKF for State Estimation May 29th,
2010 22 / 28
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UTIAS
The Unscented Kalman Filter (UKF) UKF variants
Other efficiency improvements
I Spherical-simplex sigma-points (Julier et al., 2003)I Used a
set of N + 2 sigma-points, which were chosen to minimize
the third-order moments (accurate to second-order)I Reduced
sigma-point UKF (Quine, 2006)
I Used a minimal set of N + 1 sigma-points (accurate
tosecond-order)
I Square-root Unscented Kalman Filter (van der Merwe and
Wan,2001)
I Efficient square-root form that avoids refactorizing the
statecovariance at the prediction step and reduces computational
costrequired to compute the Kalman gain
I Present additional benefits in terms of numerical stability
andensures that the state covariance is always
positive-definite
Colin McManus (UTIAS) The UKF for State Estimation May 29th,
2010 22 / 28
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UTIAS
The Unscented Kalman Filter (UKF) Summary
Strengths and weaknesses
Strengths:I Unscented Transformation is accurate to third-order
for Gaussian
systemsI Derivative-free (easy implementation)
Weaknesses:I Depending on noise assumptions, can be expensiveI
Sigma-point scaling issues
I The Scaled Unscented Kalman Filter (Julier, 2002)I Additional
weight parameters (Wan and van der Merwe, 2000)
Colin McManus (UTIAS) The UKF for State Estimation May 29th,
2010 23 / 28
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UTIAS
The Unscented Kalman Filter (UKF) Summary
Strengths and weaknesses
Strengths:I Unscented Transformation is accurate to third-order
for Gaussian
systemsI Derivative-free (easy implementation)
Weaknesses:I Depending on noise assumptions, can be expensiveI
Sigma-point scaling issues
I The Scaled Unscented Kalman Filter (Julier, 2002)
I Additional weight parameters (Wan and van der Merwe, 2000)
Colin McManus (UTIAS) The UKF for State Estimation May 29th,
2010 23 / 28
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UTIAS
The Unscented Kalman Filter (UKF) Summary
Strengths and weaknesses
Strengths:I Unscented Transformation is accurate to third-order
for Gaussian
systemsI Derivative-free (easy implementation)
Weaknesses:I Depending on noise assumptions, can be expensiveI
Sigma-point scaling issues
I The Scaled Unscented Kalman Filter (Julier, 2002)I Additional
weight parameters (Wan and van der Merwe, 2000)
Colin McManus (UTIAS) The UKF for State Estimation May 29th,
2010 23 / 28
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UTIAS
EKF and UKF Comparison Summary
Accuracy
20 15 10 5 0 5 10 15 20 25 300
0.005
0.01
0.015
0.02
0.025
0.03
0.035
0.04
0.045
0.05
x
P(x
)
True PosteriorFirstorder LinearizationUnscented
Transformation
I Tong, C. and Barfoot, T.D. A Comparison of the EKF, SPKF, and
theBayes Filter for Landmark-Based Localization, In Proceedings of
the 7thCanadian Conference on Computer and Robot Vision (CRV), to
appear.Ottawa, Canada, 31 May - 2 June 2010.
Colin McManus (UTIAS) The UKF for State Estimation May 29th,
2010 24 / 28
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UTIAS
EKF and UKF Comparison Summary
Accuracy
20 15 10 5 0 5 10 15 20 25 300
0.005
0.01
0.015
0.02
0.025
0.03
0.035
0.04
0.045
0.05
x
P(x
)
True PosteriorFirstorder LinearizationUnscented
Transformation
I Tong, C. and Barfoot, T.D. A Comparison of the EKF, SPKF, and
theBayes Filter for Landmark-Based Localization, In Proceedings of
the 7thCanadian Conference on Computer and Robot Vision (CRV), to
appear.Ottawa, Canada, 31 May - 2 June 2010.
Colin McManus (UTIAS) The UKF for State Estimation May 29th,
2010 24 / 28
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UTIAS
EKF and UKF Comparison Summary
Computational cost
I In general, EKF cost < UKF cost
I Problem dependentI UKF form:
I Additive UKFI Augmented UKF
I Sigma point reduction:I Spherical-simplex sigma-points (Julier
et al., 2003)I Reduced sigma-point UKF (Quine, 2006)
Colin McManus (UTIAS) The UKF for State Estimation May 29th,
2010 25 / 28
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UTIAS
EKF and UKF Comparison Summary
Computational cost
I In general, EKF cost < UKF costI Problem dependentI UKF
form:
I Additive UKFI Augmented UKF
I Sigma point reduction:I Spherical-simplex sigma-points (Julier
et al., 2003)I Reduced sigma-point UKF (Quine, 2006)
Colin McManus (UTIAS) The UKF for State Estimation May 29th,
2010 25 / 28
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UTIAS
EKF and UKF Comparison Summary
Computational cost
I In general, EKF cost < UKF costI Problem dependentI UKF
form:
I Additive UKFI Augmented UKF
I Sigma point reduction:I Spherical-simplex sigma-points (Julier
et al., 2003)I Reduced sigma-point UKF (Quine, 2006)
Colin McManus (UTIAS) The UKF for State Estimation May 29th,
2010 25 / 28
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Questions
Any Questions?
Colin McManus (UTIAS) The UKF for State Estimation May 29th,
2010 26 / 28
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UTIAS
Questions
References
I Julier, S., Uhlmann, J. and Durrant-Whyte, H. A New Approach
forFiltering Nonlinear Systems, Proceedings of the American
ControlConference, 1995, 3, 1628-1632.
I Julier, S. The Scaled Unscented Transform, Proceedings of
theAmerican Control Conference, 2002, 6, 4555 - 4559.
I Julier, S. The Spherical Simplex Unscented
Transformation,Proceedings of the American Control Conference,
2003.
I Quine, B. A derivative-free implementation of the extended
Kalmanfilter, Automatica, 2006, 42, 19271934.
Colin McManus (UTIAS) The UKF for State Estimation May 29th,
2010 27 / 28
-
UTIAS
Questions
References
I Tong, C. and Barfoot, T.D. A Comparison of the EKF, SPKF, and
theBayes Filter for Landmark-Based Localization, In Proceedings of
the 7thCanadian Conference on Computer and Robot Vision (CRV), to
appear.Ottawa, Canada, 31 May - 2 June 2010.
I van der Merwe, R. and Wan, E. The Square-Root Unscented
KalmanFilter for State and Parameter-Estimation, IEEE
InternationalConference on Acoustics, Speech, and Signal
Processing, 2001, 6,3461-3464.
I Wan, E. and van der Merwe, R. The Unscented Kalman Filter
forNonlinear Estimation, Adaptive Systems for Signal
Processing,Communications, and Control Symposium, 2000,
153-158.
Colin McManus (UTIAS) The UKF for State Estimation May 29th,
2010 28 / 28
Problem StatementThe Extended Kalman Filter
(EKF)OverviewExampleSummary
The Unscented Kalman Filter (UKF)OverviewExampleUKF
variantsSummary
EKF and UKF Comparison SummaryQuestions