
Model-Based Testing of Hybrid Systems 403
3
2
1
0
2.5
1.5
0.5
–0.5
–1
–1.5 –1 –0.5 0 1 20.5 1.5 2.5
x
3
2
1
0
2.5
1.5
0.5
y
–0.5
–1
–1.5 –1 –0.5 0 1 20.5 1.5 2.5
x
FIGURE 14.11
Results obtained using the guided sampling method (left) and using the uniform sampling
method (right).
Example 2. This example is a linear system with a stable focus at the origin. Its dynamics is
˙x
˙y
=
−1 −1.9
1.9 −1
×
x
y
+
u
1
u
2
.
We let the dynamics be slightly perturbed by an additive input u. The state space is the
box B =[−3, −3] ×[3,3]. The input set U = {u ∈ R
2
|||u|| ≤ 0.2}. Figure 14.11 shows the
results obtained after 50,000 iterations. We can see that again the guided sampling method