摘要:
在利用Kane方法对机器海豚进行动力学建模的基础上, 提出了一种对豚体波拟合推进进行速度优化的方法. 首先, 选取各连杆的关节角和机器海豚头部质心的坐标作为广义坐标, 对具有三个推进关节的机器海豚进行运动学分析,进而得到广义惯性力; 然后,结合对各连杆受力分析得到的广义主动力, 建立机器海豚的动力学方程. 其中, 根据尾鳍攻角所处的不同范围,分别利用升力线理论和阻力模型将尾鳍建模为有限翼展机翼或平板来计算水动力. 在此基础上, 结合豚体波拟合推进, 提出一种通过调节尾鳍关节角规律的幅度和相位来优化平均推进速度的方法. 仿真结果表明了所建模型及优化方法的有效性.
Abstract:
In this paper, a dynamic model of a robotic dolphin using Kane method is presented, and a speed optimization method based on this model is proposed to improve the proplusive speed by fitting the dolphin's wave. Firstly, the joint angle of each link and centroid's coordinate of robotic dolphin's head are selected as the generalized coordinates. Then, after analyzing the kinematic of robotic dolphin with three propulsive joints, the generalized inertia forces are given. In the meantime, the generalized active forces are obtained by analyzing the forces of each link. And thus the robotic dolphin's dynamic equations are determined. In addition, the fluke is modeled as a finite span hydrofoil or flat plate according to different ranges of its attack angle based on lifting-line theory and resistance model, respectively. Furthermore, combing the propulsion by fitting dolphin's wave, a speed optimization approach by adjusting the amplitude and phase of fluke's joint angle's profile is proposed. Finally, simulation results show that the dynamic model and optimization method are effective.