Biomedical Engineering Reference
In-Depth Information
Agonist
Force
Generator
sB
ant
+
K
st
Initial
Conditions
Eye
Position
Target
Position
1
Gain
d
Σ
Σ
Σ
s
4
+
C
3
s
3
+
C
2
s
2
+
C
1
s
+
C
0
Antagonist
Force
Generator
sB
ag
+
K
st
Η
FIGURE 13.32
Block diagram of the modified linear homeomorphic eye movement model in Eq. (13.35).
A set of parameter estimates for the oculomotor plant from the system identification
technique are
125 Nm
1
K
se
¼
32 Nm
1
K
lt
¼
4Nm
1
K
¼
66
:
1 Nsm
1
B
¼
3
:
10
3
Ns
2
m
1
J
¼
2
:
2
4 Nsm
1
B
ag
¼
3
:
2 Nsm
1
B
ant
¼
1
:
t
ac
¼
0
:
009 s
t
de
¼
0
:
0054 s
10
5
d
¼
5
:
80288
The eigenvalues for the oculomotor plant using the parameter values above are
15,
66,
1,293.
Figure 13.33 shows estimation routine results for a 15
target displacement. The accu-
racy of these results is typical for all target displacements with all subjects tested, except
for saccades with glissadic or dynamic overshoot (saccades with glissadic or dynamic
overshoot are discussed later in this chapter). Figures 13.34 and 13.35 further illustrate
the accuracy of the system identification technique parameter estimation routine by the
close agreement of the velocity and acceleration estimates with the two-point central
differences estimates.
173, and
