Graphics Programs Reference
In-Depth Information
velocity for the
(
n
+
1
)
th
observation. An implementation of the
αβγ
tracker
The tracker will follow an input whose acceleration is constant with no
steady state errors. Again, in order to reduce the error at the output of the
tracker, a weighted difference between the measured and predicted values is
used in estimating the smoothed position, velocity, and acceleration as follows:
αβγ
x
s
()
x
p
=
() α
x
0
+
(
()
x
p
()
)
(9.110)
β
---
ß
s
()
ß
s
T
ßß
s
=
(
n
1
)
+
(
n
1
)
+
(
x
0
()
x
p
()
)
(9.111)
2γ
T
2
ßß
s
()
ßß
s
-----
=
(
n
1
)
+
(
x
0
()
x
p
()
)
(9.112)
()
T
2
2
()
T
ß
s
ßß
s
-----
x
p
(
n
+
1
)
=
x
s
+
+
()
(9.113)
and the initialization process is
x
s
()
x
p
=
()
x
0
=
()
ß
s
()
ßß
s
()
ßß
s
=
=
() 0
=
x
0
()
x
0
T
()
ß
s
()
=
--------------------------------
-
+
+
x
p
x
0
+
Σ
Σ
Σ
α
1
delay,
z
+
+
+
x
s
T
ß
s
ß
p
β
---
+
+
Σ
1
Σ
delay,
z
+
+
ßß
s
T
2
T
⁄
2
2γ
T
2
-----
Σ
1
delay,
z
+
+
αβγ
Figure 9.21. An implementation for an
tracker.
Search WWH ::
Custom Search