title: Hydrodynamic investigation of a self-propelled robotic fish based on a force-feedback control method.
abstract: We implement a mackerel (Scomber scombrus) body-shaped robot, programmed to display the three most typical body/caudal fin undulatory kinematics (i.e. anguilliform, carangiform and thunniform), in order to biomimetically investigate hydrodynamic issues not easily tackled experimentally with live fish. The robotic mackerel, mounted on a servo towing system and initially at rest, can determine its self-propelled speed by measuring the external force acting upon it and allowing for the simultaneous measurement of power, flow field and self-propelled speed. Experimental results showed that the robotic swimmer with thunniform kinematics achieved a faster final swimming speed (St = 0.424) relative to those with carangiform (St = 0.43) and anguilliform kinematics (St = 0.55). The thrust efficiency, estimated from a digital particle image velocimetry (DPIV) flow field, showed that the robotic swimmer with thunniform kinematics is more efficient (47.3%) than those with carangiform (31.4%) and anguilliform kinematics (26.6%). Furthermore, the DPIV measurements illustrate that the large-scale characteristics of the flow pattern generated by the robotic swimmer with both anguilliform and carangiform kinematics were wedge-like, double-row wake structures. Additionally, a typical single-row reverse Karman vortex was produced by the robotic swimmer using thunniform kinematics. Finally, we discuss this novel force-feedback-controlled experimental method, and review the relative self-propelled hydrodynamic results of the robot when utilizing the three types of undulatory kinematics.
authors.affiliation: Museum of Comparative Zoology, Harvard University, 26 Oxford Street, Cambridge, MA 02138, USA. liwen@oeb.harvard.edu
authors.forename: L
authors.initials: L
authors.lastname: Wen
authors.forename: T M
authors.initials: TM
authors.lastname: Wang
authors.forename: G H
authors.initials: GH
authors.lastname: Wu
authors.forename: J H
authors.initials: JH
authors.lastname: Liang
mesh_terms: D000818:Animals; D040761:Biomimetic Materials; D032701:Biomimetics / Q000295:instrumentation*; D003198:Computer Simulation; D017076:Computer-Aided Design; D004867:Equipment Design; D019544:Equipment Failure Analysis; D025461:Feedback, Physiological / Q000502:physiology; D008954:Models, Biological; D010473:Perciformes / Q000502:physiology*; D012371:Robotics / Q000295:instrumentation*; D013314:Stress, Mechanical; D013550:Swimming / Q000502:physiology*; D014867:Water
chemical_list: D014867:Water