A Switching Image-Based Visual Servoing Method for Cooperative Continuum Robots.

In this paper, a full-kinematic model and a visual-servo control system for recently introduced cooperative continuum robots (CCRs) are proposed. The focus will be on operative-supportive configuration which consists of two continuum robots (CRs), coupled to perform a positioning task. First, a hybrid kinematic modeling approach based on Denavit-Hartenberg method and Cosserat rod theory is developed. An efficient control system is also introduced within which the issues related to numerical Jacobian of Cosserat-based approach are addressed. A switching image-based visual servoing (IBVS) control strategy is proposed. The switching controller enables switching between the standard and proposed scaled-and non-dimensional (SND) IBVS sub-control systems. The stability of the proposed system in the sense of Lyapunov is also proved. Extensive simulations verified that SND IBVS is well capable of reducing large error signals at the beginning of the motion. In addition, the performance of the proposed switching approach, standard IBVS, and SND IBVS are compared to highlight the effectiveness of the proposed switching controller. Robustness analysis is also included here to show that even in the presence of imaging and actuation noise, the controlled system smoothly accomplishes the positioning task with an acceptable convergence speed. [ABSTRACT FROM AUTHOR]