Uncalibrated Visual Servoing for Underwater Vehicle Manipulator Systems with an Eye in Hand Configuration Camera

Abstract

This paper presents an uncalibrated visual servoing scheme for underwater vehicle manipulator systems (UVMSs) with an eye-in-hand camera under uncertainties. These uncertainties contain vision sensor parameters, UVMS kinematics and feature position information. At first, a linear separation approach is addressed to collect these uncertainties into vectors, and this approach can also be utilized in other free-floating based manipulator systems. Secondly, a novel nonlinear adaptive controller is proposed to achieve image error convergence by estimating these vectors, the gradient projection method is utilized to optimize the restoring moments. Thirdly, a high order disturbance observer is addressed to deal with time-varying disturbances, and the convergence of the image errors is proved under the Lyapunov theory. Finally, in order to illustrate the effectiveness of the proposed method, numerical simulations based on a 9 degrees of freedom (DOFs) UVMS with an eye-in-hand camera are conducted. In simulations, the UVMS is expected to track a circle trajectory on the image plane, meanwhile, time-varying disturbances are exerted on the system. The proposed scheme can achieve accurate and smooth tracking results during simulations.

Dynamics Simulation of Grasping Process of Underwater Vehicle-Manipulator System

“…Many different control strategies for UVMS to track task trajectories were designed and carried out in recent years, such as adaptive backstepping control [30][31], model predictive control [32], sliding mode impedance control [33], and so on. Furthermore, vision based dexterous manipulation is also a useful form for underwater operations [34][35][36]. However, motion planning, advance control and sensing identification need higher technical support, these are hard to implement in practice.…”

Dynamics Simulation of Grasping Process of Underwater Vehicle-Manipulator System

“…In addition, sliding mode control of UVMS for second-order system is common and reliable, such as sliding mode impedance control [60], terminal sliding control [43,53,[61][62][63][64], dynamic sliding mode control [65], robust sliding mode control [5], multiple sliding mode methods [66], dynamic neural network [67], double-loop sliding mode control [68][69][70], adaptive sliding mode PID control [71], fuzzy sliding mode control [72][73][74][75], and so on. Furthermore, vision-based dexterous manipulation is also a useful form for underwater operations [41,[76][77][78]. However, motion planning, advance control, and sensing identification need higher technical support, and are hard to implement in practice.…”

Stereo Vision System for Vision-Based Control of Inspection-Class ROVs

“…In terms of underwater operations, visual servoing has been mainly utilised in AUVs [1,6,32,33]. Some researchers have also used this technique in ROVs for vehicle docking [3,32], vehicle navigation [34], work-class vehicle control [35], and manipulator control [33].…”

“…In terms of underwater operations, visual servoing has been mainly utilised in AUVs [1,6,32,33]. Some researchers have also used this technique in ROVs for vehicle docking [3,32], vehicle navigation [34], work-class vehicle control [35], and manipulator control [33]. Nevertheless, to the knowledge of the authors, previous research has not been as devoted as this one to utilising visual servoing for precise vehicle control at low speed and a calculated distance from the bottom in a small area.…”