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Chapter 3 – Caterpillar Locomotion 146
3. Caterpillar Locomotion
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3.1 Introduction
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Chapter 3 – Caterpillar Locomotion 147
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3.1.1 Previous Studies of Animal Locomotion
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Chapter 3 – Caterpillar Locomotion 148
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Chapter 3 – Caterpillar Locomotion 149
Left 3
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Leg is supporting —
Leg is not supporting —
Figure 3.1 — Gait Diagram of a Cockroach's "Tripod Gait". (Adapted from Wilson, (1966).)
3.1.2 Caterpillars
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Chapter 3 – Caterpillar Locomotion 150
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Figure 3.2 — Side View of a Standing Tent Caterpillar
Figure 3.3 — Side View of a Pitching Tent Caterpillar
Chapter 3 – Caterpillar Locomotion 151
Figure 3.4 — Bottom View of Turning (Yawing) Tent Caterpillar
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Chapter 3 – Caterpillar Locomotion 152
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3.2 Experimental Program
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3.2.1 Videotaping Caterpillar Locomotion
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Chapter 3 – Caterpillar Locomotion 153
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Chapter 3 – Caterpillar Locomotion 154
3.2.2 Determination of Workspace
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Chapter 3 – Caterpillar Locomotion 156
Table 3.1 — Approximate Physical and Locomotion Characteristics of Eastern TentCaterpillars
Note 1: This may not have been voluntary. Also note that this is pitching up; negative pitch was not
measured but is believed to be much smaller.
Note 2: After the experiments, when the caterpillars were released, they appeared to move much
faster than this 'maximum'. Unfortunately, this was not documented on video and so their
true top speed is unknown. The caterpillars' decision to finally demonstrate their speed
capabilities may be attributable to their pleasure at finally being released from the jar, or
more likely, the pavement was hot.
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Chapter 3 – Caterpillar Locomotion 159
Figure 3.6 — Tent Caterpillar Gait Diagram
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Chapter 3 – Caterpillar Locomotion 161
Figure 3.7 — Eastern Tent Caterpillar Climbing a Large “Hill”
3.3.2.2 Crossing Large Obstacles
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3.5 Chapter Summary
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