Page 374 - Flexible Robotics in Medicine

Robotic transluminal Pan-and-Tilt Scope 367

self-administer the monitoring of tumor growth in the nasopharynx region by obtaining the
images. Besides, the camera at the tip of the device will be steerable by merely pressing the
four buttons controlled by the motors.

16.2.1 Design requirement and aims

The design requirements and aims of the device are set to make the device safer and user-
friendly.

16. Steerable to increase the viewing angles in order to obtain a broader view of the
nasopharynx region.
2. Self-administered by patients at home without assistance from medical personnel to
save the hassle of patients visiting the hospital regularly.
3. Safe and easy to use. It is best that patients have their hands free from holding the
device so that they can control the steering of the device with both hands, thus
increasing the safety of the device.

16.2.2 Design overview

Due to the inspiration from the eyeballs, the design of the device mimicked the movement
of the eyeballs. The P.A.T.S device comprises two mechanisms, tilting mechanism and
rotation mechanism, accomplished with the following components: camera holder, tip,
sheath, servo motor, and stepper motor. The overall design of P.A.T.S is as shown in
Fig. 16.2. As shown in Fig. 16.2, P.A.T.S is a straight tube coupled with motors to facilitate
the self-administration for patients.
• Tip: The two ends of the tip have different features, serving for different purposes. The
distal end of the tip has two supports extended out, allowing the camera holder to attach
on them through the threading of two stainless steel wires. The proximal end of the tip
has a groove that will be matching with the groove at the distal end of the sheath. This
groove is the essential feature of the rotation mechanism. There are also two stainless
steel wires threading through the proximal end, and the two wires are stuck together,
acting as the axis of rotation.
• Sheath: The sheath is hollow to house the camera wire and the cables used for the
tilting and rotation mechanism. By enclosing the wires, it is ensured that the wires are
not exposed to the nasal passageway. Furthermore, the sheath also has its distinct
element, which is the groove that matches the groove of the tip. The sheath is to be
assembled with the tip by matching the groove. The groove is designed to facilitate the
rotation between the tip and the sheath.
• Servo motor and stepper motor: The servo motor is responsible for the tilting
mechanism of the device by pulling the stainless-steel wires clockwise or anticlockwise.