Page 493 - Flexible Robotics in Medicine

OmniFlex: omnidirectional flexible hand-held endoscopic manipulator with spheroidal joint 487

Figure 21.8
Functional test setup and forceps targeting/retrieving specimens.

21.5.4 Biopsy test

The setup is to mimic the actual biopsy test. The model of the biopsy test is used to test
various aspects of the prototype, including targeting ability, specimen retrieval,
contamination, and ease of use. The biopsy test setup comprises of a water bottle cut in half
and a few targeting specimens. The prototype needs to go through the bottleneck, and upon
reaching the specimen area, it will need to curve and target the specimen location
(Fig. 21.8). Then the forceps will be used to retrieve the specimen. Contamination
avoidance is measured by how clean the forceps can retrieve the specimen without touching
the nonspecific area. The prototype was able to retrieve all specimens safely within a short
period (9 minutes). As seen from the prototype, the retraction of the driving rods out of the
OmniFlex body is prevented by four channels when the proximal disc is rotated (Fig. 21.1).
Without these channels, the driving rods will slip out of the OmniFlex body and may cause
hindrance. Changes to the design of the OmniFlex container, such as increasing the length
of the body and building in guiding channels, will solve this problem.

The current design process of OmniFlex concerns the phases of feasibility and design
verification. Furthermore, the prototype’s components are easy to manufacture and
assemble, making it easier for the design transfer process. The prototype demonstrates high