Purpose

The purpose of this paper is to introduce a motion control method for WFF-AmphiRobot, which can effectively realize the flexible motion of the robot on land, underwater and in the transition zone between land and water.

Design/methodology/approach

Based on the dynamics model, the authors selected the appropriate state variables to construct the state space model of the robot and estimated the feedback state of the robot through the maximum a posteriori probability estimation. The nonlinear predictive model controller of the robot is constructed by local linearization of the model to perform closed-loop control on the overall motion of the robot. For the control problem of the terminal trajectory, using the neural rhythmic movement theory in bionics to construct a robot central pattern generator (CPG) for real-time generation of terminal trajectory.

Findings

In this paper, the motion state of WFF-AmphiRobot is estimated, and a model-based overall motion controller for the robot and an end-effector controller based on neural rhythm control are constructed. The effectiveness of the controller and motion control algorithm is verified by simulation and physical prototype motion experiments on land and underwater, and the robot can ideally complete the desired behavior.

Originality/value

The paper designed a controller for WFF-AmphiRobot. First, when constructing the robot state estimator in this paper, the robot dynamics model is introduced as the a priori estimation model, and the error compensation of the a priori model is performed by the method of maximum a posteriori probability estimation, which improves the accuracy of the state estimator. Second, for the underwater oscillation motion characteristics of the flipper, the Hopf oscillator is used as the basis, and the flipper fluctuation equation is modified and improved by the CPG signal is adapted to the flipper oscillation demand. The controller effectively controls the position error and heading angle error within the desired range during the movement of the WFF-AmphiRobot.

中文翻译：

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轮鳍翻转一体式两栖机器人CPG-MPC控制器

目的

本文的目的是介绍一种WFF-AmphiRobot运动控制方法，能够有效实现机器人在陆地、水下以及陆水过渡区的柔性运动。

设计/方法论/途径

基于动力学模型，作者选择合适的状态变量构建机器人的状态空间模型，并通过最大后验概率估计来估计机器人的反馈状态。通过模型的局部线性化构建机器人的非线性预测模型控制器，对机器人的整体运动进行闭环控制。针对终端轨迹的控制问题，利用仿生学中的神经节律运动理论，构建机器人中央模式生成器（CPG），用于实时生成终端轨迹。

发现

本文对WFF-AmphiRobot的运动状态进行估计，构建了基于模型的机器人整体运动控制器和基于神经节律控制的末端执行器控制器。通过陆地和水下仿真和物理样机运动实验验证了控制器和运动控制算法的有效性，机器人能够理想地完成期望的行为。

原创性/价值

论文为WFF-AmphiRobot设计了控制器。首先，本文在构造机器人状态估计器时，引入机器人动力学模型作为先验估计模型，并通过最大后验概率估计的方法对先验模型进行误差补偿，提高了精度的状态估计器。其次，针对鳍状肢水下振荡运动特性，以Hopf振子为基础，通过CPG信号对鳍状肢波动方程进行修正和改进，以适应鳍状肢振荡需求。控制器有效地将WFF-AmphiRobot运动过程中的位置误差和航向角误差控制在期望的范围内。