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Amphibionics 05 3/24/03 8:44 AM Page 176
Amphibionics
To make the robot snake turn to the right, the same sine wave pat-
tern will need to occur in the vertical moving body segments, but
the snake’s body will also need to oscillate between the middle
position and a position where the body is arched to the right. The
pulsout values needed to control this movement are listed in Table
5.9 and will be used when programming the snake. Figure 5.62
shows the two positions that the snake’s body will oscillate
between to turn to the right. You might have noticed that when
positioning the robot’s body to the right, smaller pulsout values
were used. This is to take into account the extra weight of the ser-
vos that are positioned on the right side of the snake’s body.

TABLE 5.9 Body Position 1
Servo Position Values
Servo and port address Pulsout value
Needed to Sequence a
Right Turn 1—PortB.2 150
2—PortB.3 210
3—PortB.7 150
4—PortB.6 100

5—PortB.5 150
6—PortB.4 210

Body Position 2
Servo and port address Pulsout value
1—PortB.2 190

2—PortB.3 100
3—PortB.7 190
4—PortB.6 210

5—PortB.5 190
6—PortB.4 100

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