Biomedical Engineering Reference
In-Depth Information
1.13.1 Robotic Surgery
Robotic surgery, or computer-assisted surgery, are terms for technological developments
that use robotic systems to aid in surgical procedures. Robotic surgery was developed to
overcome both the limitations of MIS and to enhance the capabilities of surgeons per-
forming open surgery. In the case of MIRS, instead of directly moving the instruments,
the surgeon uses one of two methods to control the instruments; either a direct telemanip-
ulator or a computer control. A telemanipulator is a remote manipulator that allows the
surgeon to perform normal movements that he would encounter during a regular surgi-
cal procedure. In computer-controlled systems the surgeon uses a computer to control the
robotic arms and its end-effectors, though these systems can also still use telemanipulators
for their input. One advantage of using the computerized method is that the surgeon does
not have to be present and, indeed, the surgeon could be located anywhere, which ushers
in the possibility for remote surgery. In the case of enhanced open surgery, autonomous
instruments (in familiar configurations) replace traditional steel tools, performing certain
actions (such as rib spreading) with much smoother, feedback-controlled motions than
could ever be achieved by a human hand. The main object of such smart instruments is
to reduce or eliminate the tissue trauma traditionally associated with open surgery, with-
out requiring more than a few minutes' training on the part of surgeon. This approach
seeks to improve that lion's share of surgeries, particularly cardio-thoracic, that minimally
invasive techniques have so far failed to supplant.
1.14 Applications
Artificial organs, like an artificial finger or artificial skin, can receive benefits from the use
of tactile sensors. For instance, the Shadow Finger Test Unit is an artificial finger which
is equipped with tactile sensors such as is used on Shadow Dextrous Hand mentioned
above (Figure 1.9). Synthetic skin, fabricated from semiconductor materials that can sense
touch, is anticipated to augment robotics in conducting rudimentary tasks that would be
considered delicate and require 'touch'. It is also expected that this technology can be
further advanced such that it can be eventually used on prosthetic limbs to restore the
sense of touch. Markets with distant palpable products may also have a future in tactile
sensing applications. Tactile sensors, which have been developed specifically for use with
industrial robots, can also complement visual systems by becoming the controlling system
during the time in which contact is made between a gripper of the robot, and the object
or objects being gripped, since it is during this time that vision is often obscured.
In robotics, tactile sensors provide useful information about the state of contact between
a robot hand and the object it is grasping. Sensors can indicate the presence or shape of
an object, its location in the hand, and the force of contact.
As previously stated, the lack of haptic feedback is evident in MIS, remote surgery
and remote manipulation tasks. Therefore, the significant challenge in the fields of tactile
sensing and displays (teletaction systems) is to provide haptic feedback in order to increase
operating dexterity and to encourage the greater use of MIS and MIRS.
In robotic telemanipulators, specifically in MIS and MIRS, and in order to provide local
shape information, an array of force generators are used to create a pressure distribution
on a fingertip that is tantamount to providing a true contact [79]. A comparatively large
Search WWH ::




Custom Search