Robotic Surgery Goes Soft
Robot-assisted surgery (RAS) has been around a long
time, but it’s worth noting that “robot-assisted” is not
synonymous with “autonomous.” For example, when using
the renowned da Vinci system, a human surgeon is in
control 100 percent of the time. Because soft tissue tends
to move around in unpredictable ways, autonomous surgery
has been applicable only to rigid anatomical items such as
bones. However, surgeons and scientists from the Sheikh
Zayed Institute for Pediatric Surgical Innovation — part of
the Children's National Health System
( childrensnational.org) — have now demonstrated
successful autonomous robotic soft tissue surgery via the
Smart Tissue Autonomous Robot (STAR) — a system
developed in-house.
Their research was actually performed on both dead
and living pigs, but the technology should be suitable for
humans as well. The study included two different surgeries:
linear suturing and end-to-end intestinal anastomosis (i.e.,
connecting two tubular structures). Comparing the STAR
surgery results with the same procedure conducted
manually, by laparoscopy, and by RAS with the da Vinci
system, it proved to be superior in terms of creating
consistent suture spacing and withstanding higher leak
pressures. (Obviously, leakage at suture points is highly
undesirable.)
Mistakes requiring needle removal were minimal, as
was constriction at the connection point. The drawback is
that the surgery took 35 minutes, whereas manually
controlled procedures took only eight minutes. This is still
comparable to the average clinical procedures.
According to the Institute, some or all of the STAR
technology could be brought into clinics within two years.
The next step in the development cycle will be to further
miniaturize the system’s tools and develop improved sensors
to allow for wider use of the system.
The STAR soft tissue surgical system.
by Jeff and Jenn Eckert
Robytes
Origami with a Purpose
As we know, children have a strange desire to put
things in their mouths that don’t belong there such as
coins, marbles, bottle caps, and coat buttons. Among the
most problematic items are the little button batteries found
in calculators, watches, remote controls, and so forth. In
fact, various sources confirm that as many as 6,000
children visit emergency rooms every year to be treated for
battery ingestion — a shocking statistic (sorry). And it’s not
just a choking issue. The battery current can react with
saliva or stomach fluids, generate hydroxide, and cause
caustic injuries to adjoining tissue. Serious damage can
occur in less than two hours, and it can even create a hole
in the esophagus.
To address the problem, researchers at MIT
( web.mit.edu), the University of Sheffield
( ww.sheffield.ac.uk), and the Tokyo Institute of
Technology ( www.titech.ac.jp/english) have developed
an ingestible origami robot that’s capable of capturing and
removing these objects, thus eliminating the need for any
surgery or
endoscopy.
The device is
folded and frozen
into an ice capsule
which dissolves
when swallowed.
The bot then
unfolds and moves
around as directed
by external magnetic fields. An attached magnet grabs the
battery, and the objects then continue through the
digestive system. Propulsion occurs through a “stick-slip”
motion in which the bot flexes to cause its appendages to
either grip or slip free. As noted by one robotics professor,
“This concept is both highly creative and highly practical,
and it addresses a clinical need in an elegant way. It is one
of the most convincing applications of origami robots that I
For a demo, search “ingestible origami robot” on
YouTube.
SERVO 09.2016 7
Origami bot removes foreign objects
from the digestive system.