Page 211 - Anatomy of a Robot

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196 CHAPTER EIGHT
15 radians per second
Actual Signal 16 radians per second 17 radians per second
Actual Signal
Actual Signal
1 1 1
0.5 0.5 0.5
0 0 0
-0.5 0 1 2 3 4 -0.5 0 1 2 3 4 -0.5 0 1 2 3 4
-1 -1 -1
Sampled Signal Sampled Signal Sampled Signal
1 1 1
0.5 0.5 0.5
0 0 0
0 0 0
-0.5 -0.5 -0.5
-1 -1 -1
18 radians per second 19 radians per second 20 radians per second
Actual Signal Actual Signal Actual Signal
1 1 1
0.5 0.5 0.5
0 0 0
-0.5 0 1 2 3 4 -0.5 0 1 2 3 4 -0.5 0 1 2 3 4
-1 -1 -1
Sampled Signal Sampled Signal Sampled Signal
1 1 1
0.5 0.5 0.5
0 0 0
0 0 0
-0.5 -0.5 -0.5
-1 -1 -1
21 radians per second 22 radians per second 23 radians per second
Actual Signal Actual Signal Actual Signal
1 1 1
0.5 0.5 0.5
0 0 0
-0.5 0 1 2 3 4 -0.5 0 1 2 3 4 -0.5 0 1 2 3 4
-1 -1 -1
Sampled Signal Sampled Signal Sampled Signal
1 1 1
0.5 0.5 0.5
0 0 0
0 0
-0.5 -0.5 -0.5 0
-1 -1 -1
24 radians per second 25 radians per second 26 radians per second
Actual Signal Actual Signal Actual Signal
1 1 1
0.5 0.5 0.5
0 0 0
-0.5 0 1 2 3 4 -0.5 0 1 2 3 4 -0.5 0 1 2 3 4
-1 -1 -1
Sampled Signal Sampled Signal Sampled Signal
1 1 1
0.5 0.5 0.5
0 0 0
0 0 0
-0.5 -0.5 -0.5
-1 -1 -1
FIGURE 8-3 Aliasing example: When sampling at 20 radians per second,
aliasing is evident past 10 and dramatic by 20.