Page 479 - Flexible Robotics in Medicine

CHAPTER 21

OmniFlex: omnidirectional flexible

hand-held endoscopic manipulator with

spheroidal joint

1
1
1
Hritwick Banerjee 1,2 , Low Rui Qi , Joel Tan Xian Zheng , Bryan Chua ,
1
Pham Tan Hung and Hongliang Ren 1
1 2
Department of Biomedical Engineering, National University of Singapore, Singapore, Max Planck
Institute for Intelligent Systems, Stuttgart, Germany

In this chapter, we discuss and design a flexible endoscopic manipulator, OmniFlex, capable of
omnidirectional rotation that can be actively controlled intuitively. Biopsy forceps with precision
control is important, so it is essential to have flexible forceps that can detach from the endoscopic
distal end to reach the area of the lesion. With this, a large field of operation of the area can be
maintained by the practitioner, hence increasing the precision. The tool bends according to the
curvature of the flexible endoscopic manipulator. Because of its compliant nature, the forceps rely
on the endoscopic manipulator for support. OmniFlex promotes ease of usage with one-hand
intuitive ball and socket control and omnidirectional curvature. Shape-lock ability, on the other
hand, enables multitasking capability. No twisting of the prototype is required to touch hard to
reach the targeted spot. The curvature angle can be about 150 degrees in all four directions.

21.1 Introduction

21.1.1 Nasopharyngeal carcinoma: origin and anatomy

Nasopharyngeal carcinoma (NPC) originates in the nasopharynx, the area behind the nose
and near the base of the skull [1]. Healthy cells proliferate in an orderly manner. In the case
of cancer, cancer cells are unable to stop proliferating and dividing, which will eventually
lead to the formation of a lump or tumor [2,3]. Therefore in nasopharyngeal cancer, cancer
cells are formed in the tissues of the nasopharynx. The most common method of diagnosis
is by collecting biopsy samples using nasal endoscopy (NE) [4]. Such a procedure will
require an operator to insert a flexible endoscopic manipulator into the nose. A camera
located at the distal end of the flexible endoscopic manipulator can survey the nasopharynx
for tumors. The operator conducting operation may collect a tissue sample by passing a

Flexible Robotics in Medicine.
DOI: https://doi.org/10.1016/B978-0-12-817595-8.00022-5 473
© 2020 Elsevier Inc. All rights reserved.