68

Figure 4.10 and Figure 4.11 show discrete RV value plots typical of the results obtained using

swing-COM RVs. Q^dis indicated by a dotted line.

0.1

0.05

0

-0.05

-0.1
-0.15

0102030405060
step

0.1

0.05

0

-0.05

0

10

20

30

step

40

50

60

(a) forward component

(b) lateral component

Figure 4.10 - Discrete RV values, Q_i^*, for L-F sampling, Q^d= [0.05,0]

0.1

0.05

0

-0.05

-0.1
-0.15

0102030405060

step

0.1

0.05

0

-0.05

0

10

20

30

step

40

50

60

(a) forward component

(b) lateral component

Figure 4.11 - Discrete RV values, Q_i^*, for SP sampling, Q^d= [0.0,0]

Overall, the results are not as good as those obtained with the up-vector RV.

The swing-COM

Q_i^*values are, in general, less stable, fall farther from their desired values with larger, more

chaotic oscillations, and demonstrate a tendency to drift. Correspondingly, the continuous motion

of the biped in most swing-COM trials is farther from a true limit cycle, qualitatively speaking.