Page 155 - Flexible Robotics in Medicine

Modular origami joint operator to create bendable motions with multiple radii 141
Table 5.9: Performance summary.

Tendon
Characteristic Pneumatics driven
Bending motion Maximum bending angle 72.3 87.9
Stability Lateral displacement (cm) 20.20 6 0.30 3.04 6 0.62
Longitudinal displacement (cm) û 1.59 6 0.16
Lateral stabilization time (s) û 0.63
Longitudinal stabilization time (s) û 0.067
Targeting accuracy Deviation of the drill bit from the center of the target û Hits target
(cm)
Repeatability Standard deviation of the maximum bending angle 2.8 7.0
(degrees)
Absolute deviation Deviation from 90 degrees 17.74 4.54

Table 5.10: Design comparative review for tendon and vacuum approaches.
Pneumatics Tendon driven
Fabrication Longer fabrication process Easier to fabricate
Ensure no leaks
Cost- More expensive due to more equipment required Cheaper
effectiveness
User More parameters need to be controlled (Relationship Motor is used to
friendliness between voltage and bending motion needs to be clearly control bending
identified.) motion
Leaks can be problematic and dangerous
Workspace Larger workspace as a DC supply and a vacuum pump is Smaller workspace
required required
Motor is used to
control bending
motion

accompanying components of a bronchoscope will be mentioned purely for reference. The
patent coverage of MOJO design will also apply to the manufacturing of the said joint as
well as the use of the said joint in a medical procedure such as TT.

5.5.1 Search strategy

Patents in the domain of steerable rigid and flexible endoscopes are considered. The relevant
patents were found primarily by searching the US Patent and Trademark Office and the
World Intellectual Property Organization database. The search engine used was Google. In
the search using Boolean operators, all OR and NOT terminologies were coupled with each
individual AND terminology. Please refer to Table 5.11 for the list of keywords to filter out
the most relevant patents. The selected patents are listed in Table 5.12.