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OmniFlex: omnidirectional flexible hand-held endoscopic manipulator with spheroidal joint 483

The active end consists of two connecting spacers (adapters) and one middle spacer along
with the forceps and spring. Connecting spacer connects tension spring (3 mm diameter)
and compression spring (4.5 mm diameter), and connects compression spring and forceps.
The cables are put outside the spring to maximize the moment arm, thus increasing
precision and ease of control. This product is designed to work with the current
manipulator. Hence the instrumentations are like a conventional nasal endoscopic biopsy
procedure, which may include bronchoscope, light source, image processor, etc.

21.4 Benchmarking

To use the OmniFlex, one must first ensure that the manipulator working diameter is large
enough to house the OmniFlex working tube. Like how a usual biopsy operation is
conducted, the manipulator is first inserted into the nasal cavity. The operator uses the
distal camera to navigate to the target site before the OmniFlex is passed through the
working channel of the manipulator. Once inserted, the OmniFlex distal tool should extend
beyond the distal orifice of the manipulator working channel and come into view of the
camera. The operator can then use the camera to navigate the actively controllable distal
tool of the OmniFlex to the biopsy tissue. A single hand is required for both the actuation
of curvature and the opening and closing of the forceps, allowing the operator to grab the
target tissue quickly without the need for extensive hand actions.
In many ENT procedures, the ENT specialists will encounter head and neck regions that
contained vital organs and structures such as the brain, facial motor nerves, and sensory
centers. This region also contains significant blood vessels and can lead to severe
complications or even death if damaged. Therefore the ENT manipulator shall be steerable
at the distal tip to navigate the area and avoid contact with the surrounding tissues. With the
ease of accessibility of the parts and having a small number of parts, OmniFlex can scale-
down in size to make it even smaller and portable. Additionally, it is compact, hand-held,
and easy to operate. Being omnidirectional and with actively steerable forceps, OmniFlex
can maneuver contours and anatomical curves effectively inside the nasal cavity.

Flexible endoscopic manipulators are the ideal prototypes to use as benchmarking tools
because the OmniFlex must complement the existing endoscopic prototypes. Therefore
defined metrics should match or surpass the capabilities of the existing flexible endoscopic

Table 21.3: Needs table for designing better OmniFlex.

Need no. Prototype part Customer need Importance
1 Distal tool (forceps) Capable of collecting a tissue sample 1
2 Distal end High DOF for maneuverability 1
3 Entire working length Small in dimension 1
5 Proximal control Intuitive 2