a)
b)
Micro-patterned PDMS tread
Quarter
Camera
with LEDs
IR emitters Motor
Timing pulley
Tefon rollers
Tether
ROBOTICS continued
to traverse slippery, tubular environments, the device became
bogged down with biological tissue and eventually stopped
working,” says Valdastri, who is also principal investigator at Vanderbilt’s Science and Technology of Robotics in
Medicine (STORM) Lab.
“The robotic platform for colonoscopy we are currently working on at the STORM Lab is based on closed-loop
magnetic guidance of a soft-tethered endoscopic capsule using a remote seven-degree-of-freedom robotic arm. All the
major developers of capsule endoscopes like Given Imaging
and Olympus are moving in the same direction and magnetic platforms to control wireless ingestible cameras are concretely the next revolution in the field of gastrointestinal endoscopy.” 7 There is even an untethered soft-capsule robot
from Carnegie Mellon University (Pittsburgh, PA) that can
be rolled inside the stomach using remote magnetic actuation. 8 This soft capsule offers noninvasive stomach imaging,
drug delivery, and can even conduct biopsy and elastogra-phy by a doctor’s direct control.
Beyond magnetics, other means of mobility being explored
for RCEs include biomimetic robotic feet fitted with photo-
lithographically patterned silicon pads from the University
of Leeds that mimic the “sticky” feet of tree frogs for motion
inside the abdomen (see http://youtu.be/X Trogpss6W0) and
micro-patterned polydimethylsiloxane (PDMS) treads from
the University of Colorado (Boulder, CO). 9, 10 The treads—
driven by a gear train and a direct-current motor within
FIGURE 4. A robotic capsule endoscope traverses the GI tract
using patterned treads that simulate the action of insect feet.
(Courtesy of University of Colorado)
FIGURE 5. Jasmine (a), and I-SWARM (b) microrobots represent
different generations of microrobotic design; the microrobots
have shrunk in size from 3 cm3 (for Jasmine) down to 3 mm3 (for
I-SWARM). (Courtesy of Open Source; www.swarmrobot.org)