Combined dynamics and kinematics networked fuzzy task priority motion planning for underwater vehicle-manipulator systems

Yanhui Wei,Qiangqiang Li,Shanshan Luo,Jishun Xie,Yongkang Hou

doi:10.1177/17298814211012229

Yanhui Wei, Qiangqiang Li + Show 3 more

Open Access

https://doi.org/10.1177/17298814211012229

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Abstract

The underwater vehicle-manipulator systems (UVMS) face significant challenges in trajectory tracking and motion planning because of external disturbance (current and payload) and kinematic redundancy. Former algorithms can finish the tracking of end-effector (EE) and free of singularity redundancy solution alone. However, only a few analytical studies have been conducted on coordinated motion planning of UVMS considering the dynamics controller. This article introduces a combined dynamics and kinematics networked fuzzy task priority motion planning method to solve the above problems. It avoids the assumption of perfect dynamic control. Firstly, to eliminate the kinematics error, a dynamic transformation method from joint space to task space is proposed. Without chattering, an outer loop sliding mode controller is designed for tracking EE’s trajectory. Further, to ensure the underwater vehicle’ posture stability and joint constraint, a task priority frame with kinematics error is used to planning the coordinated motion of UVMS, in which the posture and joint limits map into the null space of prioritized tasks, and weight gains are adopted to guarantee orthogonality of secondary tasks. On top of that, the gain weighted are updated by the networked fuzzy logic. The proposed algorithm achieves better coordinated motion planning and tracking performance. Effectiveness is validated by numerical simulation.

Highlights

The vehicle-manipulator system has a more complex external environment and force characteristics in the space and ocean
Kim et al.[13] solved kinematics singularity by dynamic distributing tasks based on task priority (TP) method
It is worth noticing that the problem of uncertainty and external disturbance, as the precondition of underwater vehicle-manipulator systems (UVMS) coordinated motion planning, is based on a sliding mode controller.[22]

Summary

Introduction

The vehicle-manipulator system has a more complex external environment and force characteristics in the space and ocean. To the best of the authors’ knowledge, researchers have proposed a variety of trajectory planning methods for UVMS at different criteria, such as obstacle avoidance,[12] free of singularity,[13] shortest time,[2,14] optimal torque, and lowest energy consumption.[15] Kim et al.[13] solved kinematics singularity by dynamic distributing tasks based on task priority (TP) method. Under this idea, it is easy to obtain the TP refactoring criteria and evaluate its performance. In the process of combined kinematics and model uncertainty error, the quality of control still needs to be improved

Design specifications

Design of a tracking controller

Findings

Conclusions