线驱动仿海豹尾部推进机构设计与运动学分析  

Design and Kinematics Analysis of a Wire-Driven Propulsion Mechanism Inspired by the Seal Aft Fin

作　　者：刘玉红[1] 刘书赫 邓仕晗 李厚存 冯登雪 Liu Yuhong;Liu Shuhe;Deng Shihan;Li Houcun;Feng Dengxue(School of Mechanical Engineering,Tianjin University,Tianjin 300072,China)

机构地区：[1]天津大学机械工程学院,天津300072

出　　处：《天津大学学报（自然科学与工程技术版）》2022年第2期133-142,共10页Journal of Tianjin University：Science and Technology

基　　金：国家自然科学基金资助项目(51675372,51721003);天津市自然科学基金资助项目(18JCTPJC49100).

摘　　要：仿生推进由于具有速度快、效率高、机动性好、噪声污染低等优势,在水下机器人领域备受青睐.基于对海豹尾部生物结构及运动特征的研究,提出并设计了一种基于线驱动原理并结合柔性铰链机构的仿海豹尾部摆动推进机构.该机构包括脊椎框架单元、骨盆单元、胫骨单元以及柔性尾鳍单元,其关节采用柔性铰链,并通过两侧弹性元件的对称布置,可实现由单一舵机驱动仿生推进机构实现周期性摆动动作.采用D-H参数法对推进机构进行运动学分析,确定了推进机构尾鳍末端点在世界坐标系中的坐标,研究了仿生推进机构等效连杆摆角参数(摆动角、摆动幅值、初始角)对推进机构摆动幅值的影响规律.根据运动学分析结果,采用序列二次规划法对设计的仿生推进机构等效连杆摆角参数进行了优化,获得了与海豹尾部摆动幅值一致的最佳运动参数;在与海豹相同的游动速度下,推进机构尾鳍末端点的摆动轨迹与生物海豹的摆动轨迹基本吻合,验证了优化分析的正确性.在空气中进行原理样机摆动实验,通过摄像机连续拍摄的运动序列图,获得了实验样机尾鳍的摆动轨迹拟合曲线,与优化后的理论曲线对比,进一步验证了仿海豹尾部推进机构设计与分析的正确性.Bionic propulsions have attracted much attention due to their advantages of fast speed,high efficiency,good maneuverability,and low noise pollution.Based on the research on the biological structure and movement characteristics of the seal aft fin,a swing propulsion mechanism is proposed and designed based on the wire-driven principle and a flexible hinge mechanism.The mechanism includes a spine frame unit,a pelvis unit,a tibia unit and a flexible seal aft fin unit.The joints adopt flexible hinges,and with the symmetrical arrangement of elastic elements on both sides,the bionic propulsion mechanism can be driven by a single steering gear to realize periodic swing.The D-H parameter method was used to conduct the kinematics analysis for the bio-inspired propulsion mechanism,and the coordinates of the seal aft fin endpoint in the absolute coordinate system were determined.The effect of the swing angle parameters(swing angle,swing amplitude and initial angle)of the equivalent connecting rod of the bionic propulsion mechanism on the swing amplitude of the propulsion mechanism is studied.According to the results,the swing angles of the equivalent connecting rods were optimized by the sequential quadratic programming method,and the best motion parameters consistent with the swing amplitude of the seal aft fin were obtained.At the same swimming speed as the seal,the swing trajectory of the seal aft fin unit basically matches that of the biological seal,which verifies the correctness of the optimization analysis.The swing experiment of the prototype is carried out in the air.The swing trajectory of the experimental prototype is obtained through the motion sequence diagrams continuously taken by the camera,which is compared with the optimized theoretical trajectory.The correctness of the design and analysis of the bio-inspired propulsion mechanism inspired by the seal aft fin was further verified.

关 键 词：仿海豹尾部推进机构 线驱动 柔性铰链 运动学分析 D-H参数法 

分 类 号：TH113.2[机械工程—机械设计及理论]