| Popis: |
Locomotor behaviors enable an organism to move through their environment to access distributed resources, and are important for capturing prey or avoiding predators. Predation and escape behaviors often require maximal performance, whereas general locomotion requires efficiency. In fish, the major aspects of locomotion studied are steady forward swimming and escape responses. These behaviors are important for understanding how fish succeed in their environment, but few studies investigate the performance of routine turn behaviors. These behaviors make up a large portion of a fish’s locomotor repertoire and understanding their performance will lead to a better understanding of how fish function in their habitats. This dissertation consists of three chapters that progressively explore the kinematics and performance of routine behaviors of fish. First, I describe fundamental kinematics of the routine turns, including body deformation kinematics and whole-body kinematics. Second, I use the insights from my kinematics experiments to design a new control scheme for multi-link fish robots, and compare its turning performance with other control schemes from the literature. Third, I use live fish and a robotic model that span a range of body depths to investigate the effect of increasing body depth on maneuverability. I conclude that heading change is primarily affected by body curvature, and accelerations are affected by the duration of the bending event. My new robotic control scheme was better at limiting recoil and maintaining acceleration but was poorer at total heading change and maximum centripetal acceleration when compared to the other control schemes. I found small differences in turn performance among live fish with different body shapes, but found that increasing body depth improved turn performance in the robot. The results of these experiments add important observations about the performance of routine maneuvers in fish. They also raise questions about the neuromuscular and hydrodynamic mechanisms that govern body shape deformation and turn performance that can be investigated in future studies. |
