Page 169 - Flexible Robotics in Medicine

Handheld flexible robot with concentric tubes aiming for intraocular procedures 155

unlike the aforementioned devices, where the rotary actuator rode on the translation axis,
here, a gear train is used to rotate the tube from a distance. The result is a neat solution,
which allows for easy changing of the tube [22].

Unlike the earlier devices, the device proposed in ref. [23] was a handheld steerable needle
for percutaneous interventions. The proposed device was a modified biopsy needle, with a
similar actuation mechanism, as illustrated in Fig. 6.4. Here a solid rod known as a stylet
has a slight curve at its tip and sits inside of a stiff cannula. The stylet is longer than the

Figure 6.4
Needle-steering concept.