Exploration of swimming performance for a biomimetic multi-joint robotic fish with a compliant passive joint

2020 ◽  
Vol 16 (2) ◽  
pp. 026007
Author(s):  
Di Chen ◽  
Zhengxing Wu ◽  
Huijie Dong ◽  
Min Tan ◽  
Junzhi Yu
Soft Robotics ◽  
2017 ◽  
Vol 4 (3) ◽  
pp. 202-210 ◽  
Author(s):  
Ardian Jusufi ◽  
Daniel M. Vogt ◽  
Robert J. Wood ◽  
George V. Lauder

Author(s):  
Hongwei Ma ◽  
Yueri Cai ◽  
Yuliang Wang ◽  
Shusheng Bi ◽  
Zhao Gong

Purpose The paper aims to develop a cownose ray-inspired robotic fish which can be propelled by oscillating and chordwise twisting pectoral fins. Design/methodology/approach The bionic pectoral fin which can simultaneously realize the combination of oscillating motion and chordwise twisting motion is designed based on analyzing the movement of cownose ray’s pectoral fins. The structural design and control system construction of the robotic fish are presented. Finally, a series of swimming experiments are carried out to verify the effectiveness of the design for the bionic pectoral fin. Findings The experimental results show that the deformation of the bionic pectoral fin can be well close to that of the cownose ray’s. The bionic pectoral fin can produce effective angle of attack, and the thrust generated can propel robotic fish effectively. Furthermore, the tests of swimming performance in the water tank show that the robotic fish can achieve a maximum forward speed of 0.43 m/s (0.94 times of body length per second) and an excellent turning maneuverability with a small radius. Originality/value The oscillating and pitching motion can be obtained simultaneously by the active control of chordwise twisting motion of the bionic pectoral fin, which can better imitate the movement of cownose ray’s pectoral fin. The designed bionic pectoral fin can provide an experimental platform for further study of the effect of the spanwise and chordwise flexibility on propulsion performance.


Robotica ◽  
2009 ◽  
Vol 27 (7) ◽  
pp. 1075-1089 ◽  
Author(s):  
Yonghui Hu ◽  
Wei Zhao ◽  
Guangming Xie ◽  
Long Wang

SUMMARYA novel ostraciiform swimming, vision-based autonomous robotic fish is developed in this paper. Its feasibility and capability are shown by implementing a dynamic target following task in a swimming pool. Inspired by boxfish that is highly stable and fairly maneuverable, the robotic fish is designed and constructed by locating multiple propulsors peripherally around a rigid body. Swimming locomotion of the robotic fish is achieved through harmonic oscillations of the tail and pectoral fins. The forces and moments acting on the fins and body are analyzed and the governing motion equations are derived. Through coordinating the movements of the propulsors, several typical swimming patters are empirical designed and realized. A digital camera is integrated in the robotic fish, and the visual information is processed with the embedded microcontroller. To treat the degradation of underwater image, a continuously adaptive mean shift (Camshift) algorithm is modified to keep visual lock on the moving target. A fuzzy logic controller is designed for motion regulation of a hybrid swimming pattern, which employs synchronized pectoral fins for thrust generation and tail fin for steering. A simple target following task is designed via an autonomous robotic fish swimming after a manually controlled robotic fish with fixed distance. The swimming performance of the robotic fish is tested and the effectiveness of the proposed target following method is verified experimentally.


2021 ◽  
pp. 107754632199760
Author(s):  
Hongzhou Jiang ◽  
Yanwen Liu

Compliant robotic fish can achieve a better swimming performance than rigid-bodied robotic fish. Therefore, this article investigates the swimming behavior of the compliant robotic fish based on a new swimming model that combines the large-amplitude elongated-body theory with decoupled natural orthogonal complement matrices. The simulation reveals that the multi-order resonances are generated in tail-beat amplitude, forward speed, stride length, and transport efficiency when the compliant robotic fish is driven at the corresponding frequency. Moreover, the resonant effects demonstrate the nonlinear behaviors as the driving torque increases. A control strategy for resonance utilization is presented to improve the performance capabilities. The potential influence factors for resonant effects are also discussed, showing that the tail-generated hydrodynamic force significantly impacts the resonant effect. These nonlinear characteristics can provide important guidelines for the motion control of the compliant robotic fish.


Author(s):  
Cui Zuo ◽  
Jiang Hong-zhou

Previous biological experiments show that the fish use their muscles to stiffen their bodies for improving the swimming performance. Inspired by that, we propose a planar model of oscillatory propulsor with variable stiffness using hyper redundant serial-parallel mechanisms to mimic a fish. Our goal in the paper is to identify the swimming characteristics with respect to the body stiffness. Moreover, a simulation model is presented and its results show that the swimming performance is largely dependent on the body stiffness and the driven frequency. Our primary conclusions include: 1) when the driven frequency is closed to the design frequency, the robotic fish with the calculated body stiffness has a super swimming performance. 2) Driven at the design frequency, the forward speed of robotic fish is linearly proportional to the driving frequency and the Strouhal number is consistent with the experiment results 0.25<St<0.35.


Author(s):  
Paul Phamduy ◽  
Raymond Le Grand ◽  
Maurizio Porfiri

Biomimetic robotic fish exhibits have been an attraction for many visitors in informal learning settings. Although these exhibits are entertaining to the visitors, they generally lack interactive components to promote participants’ engagement. Interactivity in exhibits is an increasing trend in public educational venues, and is a crucial factor for promoting science learning among participants. In this work, we propose a novel platform for enhancing participant interaction through a robotic fish controlled by a touch screen device. Specifically, we develop and characterize a robotic fish based on a multi-link design with a pitch and buoyancy control system for three-dimensional biomimetic swimming. Performance tests are conducted to assess the robotic fish speed.


Soft Robotics ◽  
2019 ◽  
Vol 6 (4) ◽  
pp. 520-531 ◽  
Author(s):  
Bingxing Chen ◽  
Hongzhou Jiang

2018 ◽  
Vol 2018 ◽  
pp. 1-12 ◽  
Author(s):  
Wenjing Zhao ◽  
Aiguo Ming ◽  
Makoto Shimojo

To design a soft robotic fish with high performance by a biomimetic method, we are developing a soft robotic fish using piezoelectric fiber composite (PFC) as a flexible actuator. Compared with the conventional rigid robotic fish, the design and control of a soft robotic fish are difficult due to large deformation of flexible structure and complicated coupling dynamics with fluid. That is why the design and control method of soft robotic fish have not been established and they motivate us to make a further study by considering the interaction between flexible structure and surrounding fluid. In this paper, acoustic fluid-structural coupling analysis is applied to consider the fluid effect and predict the dynamic responses of soft robotic fish in the fluid. Basic governing equations of soft robotic fish in the fluid are firstly described. The numerical coupling analysis is then carried out based on different structural parameters of soft robotic fish. Through the numerical analysis, a new soft robotic fish is finally designed, and experimental evaluation is performed. It is confirmed that the larger swimming velocity and better fish-like swimming performance are obtained from the new soft robotic fish. The new soft robotic fish is developed successfully for high performance.


Sign in / Sign up

Export Citation Format

Share Document