Performance constraints on the maneuverability of flexible and rigid biological systems

• Main Author: Frank E. Fish
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Published: 1999
• Subjects: Humpback Whale
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.538.6283; http://darwin.wcupa.edu/~biology/fish/pubs/pdf/1999AUSI99.pdf

ABSTRACT- Flexible bodies possessed by fish and marine mammals have been shown to permit high levels of performance with respect to maneuverability. However, flexibility has been avoided in the construction of engineered vehicles. Mechanisms to enhance turning performance with rigid bodies were assessed for the whirligig beetle and the humpback whale. Whirligig beetles swim rapidly in circular patterns. Curved trajectories were executed as powered turns by asymmetrical rowing of the legs, or by increased drag from the abducted elytra in combination with vectored thrust generated from sculling of the wing. Minimum relative radius was 24 % of body length. Maximum rate of turn was 4428 deg/s with maximum centripetal acceleration of 2.86 g. Humpback whales use elongate, winglike flippers to develop lift which is resolve into centripetal force to drive the turn. The relative minimum turning radius predicted from flipper structure was 82 % of body length. Compared to vertebrates with flexible bodies, the turning performance of rigid bodied beetles and whales is constrained; however, use of appendages can enhance turning performance.