MechE Colloquium: Stability and body mechanics during swimming in fish
Event details
| Date | 12.10.2021 |
| Hour | 12:15 › 13:15 |
| Speaker | Prof. Eric Tytell, Department of Biology, Tufts University |
| Location | Online |
| Category | Conferences - Seminars |
| Event Language | English |
Abstract:
Most fishes are statically unstable. Without active movements of their bodies and fins, they cannot maintain a normal upright posture. The swimming movement itself is also unstable, since the thrust force from the tail is located behind the center of mass. Despite these intrinsic instabilities, most fish are dynamically stable to a wide range of perturbations. How do they maintain stability? My lab has been investigating this question both experimentally and computationally. We are quantifying static stability by measuring the location of the center of mass and center of buoyancy in fishes. Even in a computational model with constant density, different body shapes and stiffnesses have different stability. We are also considering dynamic stability by perturbing fish with a water jet and describing the fin movements they use to compensate. These fin movements appear to be driven by the central nervous system, but are strongly dependent on sensory inputs from mechanosensors in the fin. By controlling the fins, fish can regulate whole-body posture, but also the twisting movements of different parts of the body. These twisting movements, in turn, may generate upward forces to maintain or change position vertically. With these studies, we are starting to identify some of the key ways in which fish maintain stability in three dimensions.
Bio:
Eric D. Tytell received the B.A. degree from the University of North Carolina at Chapel Hill in Biology and Physics in 1998, then the M.Phil. from the University of Cambridge in Zoology in 1999, and the Ph.D. degree in Biology from Harvard University in 2005.
He is an Associate Professor in the biology department at Tufts University, where his laboratory works on the biomechanics, muscle physiology, and neural control of swimming in a wide range of fish species, including experimental and computational work on individual fish and on schools of interacting fish. He enjoys hiking with his wife and two children, running, skiing, and playing board games. For more information, see the lab website here: https://sites.tufts.edu/tytelllab/.
Most fishes are statically unstable. Without active movements of their bodies and fins, they cannot maintain a normal upright posture. The swimming movement itself is also unstable, since the thrust force from the tail is located behind the center of mass. Despite these intrinsic instabilities, most fish are dynamically stable to a wide range of perturbations. How do they maintain stability? My lab has been investigating this question both experimentally and computationally. We are quantifying static stability by measuring the location of the center of mass and center of buoyancy in fishes. Even in a computational model with constant density, different body shapes and stiffnesses have different stability. We are also considering dynamic stability by perturbing fish with a water jet and describing the fin movements they use to compensate. These fin movements appear to be driven by the central nervous system, but are strongly dependent on sensory inputs from mechanosensors in the fin. By controlling the fins, fish can regulate whole-body posture, but also the twisting movements of different parts of the body. These twisting movements, in turn, may generate upward forces to maintain or change position vertically. With these studies, we are starting to identify some of the key ways in which fish maintain stability in three dimensions.
Bio:
Eric D. Tytell received the B.A. degree from the University of North Carolina at Chapel Hill in Biology and Physics in 1998, then the M.Phil. from the University of Cambridge in Zoology in 1999, and the Ph.D. degree in Biology from Harvard University in 2005.
He is an Associate Professor in the biology department at Tufts University, where his laboratory works on the biomechanics, muscle physiology, and neural control of swimming in a wide range of fish species, including experimental and computational work on individual fish and on schools of interacting fish. He enjoys hiking with his wife and two children, running, skiing, and playing board games. For more information, see the lab website here: https://sites.tufts.edu/tytelllab/.
Practical information
- General public
- Free