Page 210 - Anatomy of a Robot

08_200256_CH08/Bergren 4/10/03 4:39 PM Page 195
3 radians per second
5 radians per second
Actual Signal
Actual Signal 4 radians per second DIGITAL SIGNAL PROCESSING (DSP) 195
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
6 radians per second 7 radians per second 8 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
9 radians per second 10 radians per second 11 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
12 radians per second 13 radians per second 14 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 8-2 Sampling Theorem example: When sampling at 20 radians per
second, things break down for signals faster than 10.