This paper addresses the novel design of a biomimetic underwater vehicle (BUV) propelled by undulatory fins and its heading control problems. Inspired by the cuttlefish, which can perform flexible motions by undulatory propulsion in narrow spaces, our BUV with two undulatory fins is designed. The specific implementation of mechanical structure is elaborated. Moreover, a hybrid heading control which combines active disturbance rejection control (ADRC) with fuzzy strategy is proposed to achieve accurate heading control for this BUV. In the end, experimental results demonstrate the feasibility and effectiveness of the mechanism and control system.
Various autonomous underwater vehicles (AUVs) have been developed as ocean industries have grown rapidly (Blidberg, 2001; Ayutthaya, Tiaple, Laitongdee and Iamraksa, 2014). Nevertheless, operations in dangerous and worse environments are more complicated. To address increasing demands for high mobility, robustness and improved disturbance rejection, many researchers and engineers have attempted to design biomimetic AUVs. (Chu, Lee, Song, Han, Lee, Kim, Kim, Park, Cho and Ahn, 2012).
Recently, many BUVs propelled by undulatory fins have been built (Curet, Patankar, Lauder and MacIver, 2011; Hu, Low, Shen and Xu, 2012; Zhou and Low 2012; Rahman, Sugimori, Miki, Yamamoto, Sanada and Toda, 2013). However, most of researchers focus on undulatory fin control, but seldom consider precise heading control for those BUVs in underwater missions.
Heading control is a vital issue for the successful operation of a BUV. Although prior researchers have achieved satisfactory performance (Perez, 2006; Yu, Bao and Nonami, 2008), most heading controllers only aim to obtain the course stabilization of ships by steering the rudder angle, which is quite different from that of BUVs by coordinating the fins. Few researchers have presented some effective approaches to deal with heading control for BUVs (Wei, Wang, Wang, Zhou and Tan, 2015). They proposed a course controller to make a BUV rotate to a given angle in situ, while it's more helpful to control the heading of BUVs at a certain swimming speed.
