Tendon-driven continuum robot for neuroendoscopy: validation of extended kinematic mapping for hysteresis operation

Abstract

Purpose The hysteresis operation is an outstanding issue in tendon-driven actuation—which is used in robot-assisted surgery—as it is incompatible with kinematic mapping for control and trajectory planning. Here, a new tendon-driven continuum robot, designed to fit existing neuroendoscopes, is presented with kinematic mapping for hysteresis operation. Methods With attention to tension in tendons as a salient factor of the hysteresis operation, extended forward kinematic mapping (FKM) has been developed. In the experiment, the significance of every component in the robot for the hysteresis operation has been investigated. Moreover, the prediction accuracy of postures by the extended FKM has been determined experimentally and compared with piecewise constant curvature assumption (PCCA). Results The tendons were the most predominant factor affecting the hysteresis operation of the robot. The extended FKM including friction in tendons predicted the postures in the hysteresis operation with improved accuracy (2.89 mm and 3.87 mm for the single and the antagonistic tendons layouts, respectively). The measured accuracy was within the target value of 5 mm for planning of neuroendoscopic resection of intraventricle tumors. Conclusion The friction in tendons was the most predominant factor for the hysteresis operation in the robot. The extended FKM including this factor can improve prediction accuracy of the postures in the hysteresis operation. The trajectory of the new robot can be planned within target value for the neuroendoscopic procedure by using the extended FKM.

Positioning and stiffening of an articulated/continuum manipulator for implant delivery in minimally invasive surgery

“…For those cases, either model‐less or model‐based control approaches could be pursued. Model‐based approaches, in particular, would benefit from the development of a stiffening model also accounting for frictional effects, which are complex to model even for simple contact geometries and sensibly depend on the specific manipulator . An additional limitation of our study is due to the fact that we used an auxiliary external sensor for compensation during stiffening: a stronger demonstration should be based on image processing, by leveraging the tip cameras integrated in the manipulator.…”

“…In addition, a few “hybrid” articulated/continuum designs have been recently proposed. The manipulator in Kato et al introduced rigid links connected by rolling joints around a cylindrical elastic backbone. An elastic tube surrounded by rigid vertebras also acting as wire guides was similarly introduced in Li et al: the vertebras formed rotational joints (friction‐based sliding), and the authors proposed to insert a rigid tube within the aforementioned elastic one in order to also control the length of the bendable section.…”

Hysteresis analysis of a notched continuum manipulator driven by tendon

“…Kato et al (2016) took hysteresis of a tendon-driven continuum robot for neuroendoscopy into account by adding friction coefficient into their model instead of using fitting parameters, and this research only worked out the hysteresis caused by the friction. However, the hysteresis effect of our proposed continuum manipulator has many factors, including the hysteresis property of HNA and the elastic deformation of tendon (CruzHernandez and Hayward, 1998), as well as the friction and backlash happened in the tendon transmission (Swevers et al, 2000).…”

Development of a novel robotic platform with controllable stiffness manipulation arms for laparoendoscopic single‐site surgery (LESS)

“…17 However, the small-scale on-board micromotors provide limited payload capability for the manipulation arm, and larger, more powerful motors inevitably result in a large-scale arm. Snake-like continuum manipulation arm that provides high flexibility, dexterity, obstacle-avoidance capability, and potential for miniaturization, has been investigated by many researchers for LESS applications, including the 14-DoF continuum robot IREP, 18 unfoldable continuum mechanism, 19 tendon-driven continuum snake robot 20 and highly articulated robotic probe. 21 However, they would be less accurate than fully actuated articulated arms due to the highly redundant DoFs, making it difficult to perform fine movements such as knotting and suture-tying.…”