Development of 2D maneuverable robotic fish propelled by multiple ionic polymer-metal composite artificial fins

Due to their high propulsion efficiency, stealthiness, and compact size, bio-inspired robotic fish are promising underwater vehicles that can carry out remote sensing missions in intelligence collection, environmental monitoring, and fishing agriculture. In this paper, a two-dimensional (2D), maneuverable, bio-inspired robotic fish propelled by multiple ionic polymer-metal composite (IPMC) artificial fins is developed. The robot utilizes two pectoral fins for steering and one caudal fin for main propulsion. IPMC artificial muscles are used as actuators in all fins. These IPMC fins are designed and fabricated. An on-board micro-controller with a lithium ion battery and XBee communication device is developed for the robotic fish. Finally, a free-swimming robotic fish is assembled and tested. In its first demonstration of free swimming, the forward-swimming speed reached 0.5 cm/sec, and both the left-turning and right-turning speeds reached up to 1.5 rad/sec. Experimental results have verified the 2D maneuvering capability of robotic fish through multiple-fin propulsion.