Most
of us dread an experience at the hospital. The medics often use invasive
methods that cause us pain and discomfort. Sometimes the method involves a
lengthy meticulate process, usually a surgery, which is both costly and takes a
long time to heal. What if we could go to the hospital, swallow a tiny device
that gets into living tissue and the doctor would control it to carry out a
procedure? Not imaginable? It shouldn’t be. It can be done with a small enough
for injection without leaving a wound, new microrobots could revolutionize the
way modern medicine treats certain hard-to-reach areas of the body. The eyes
and brain are extremely tricky places for surgeons, and a non-invasive solution
to certain ailments has long been sought. Micro robotics or microbots is the field of miniature robotics, in
particular mobile robots with characteristic dimensions less than 1 mm.
Due to their small size, microbots
are potentially very cheap, and could be used in large numbers to explore
environments which are too small or too dangerous for people or larger robots.
It is expected that microbots will be useful in applications such as looking
for survivors in collapsed buildings after an earthquake, or crawling through
the digestive tract. What microbots lack in computational power, they can make
up for by using large numbers, as in swarms of microbots. The development of
wireless connections, especially Wi-Fi has greatly increased the communication
capacity of microbots, and consequently their ability to coordinate with other
microbots to carry out more complex tasks.
Magnetic Microbots are already in use for various operations, such as removing
plaque from a patient's arteries or helping with ocular conditions and disease
screenings.
Another application of the micro
robotics is in space exploration.
They can be used for planetary exploration, making them next-generation
instruments for in-situ chemical and mineralogical analyses on
extra-terrestrial planets. It's easy to imagine relatively
lightweight micro-robots routinely probing the entire solar system. The
challenge of building space-borne robots is in making significant decisions on
their own. Radio signals can take hours to reach distant parts of the solar
system thus remote control from the earth is not effective. This filed of
microbots is still significantly in the research stage and wide deployment is
not expected.
Microbots can be flexible and deformable
to enable them to work in uncertain and dynamic environments. Researchers are
working on various materials that our bodies can tolerate and would respond
positively to body fluids. Stimuli-responsive
hydrogels are a class of materials closely resembling biological tissues in
their physical and chemical properties. These materials have unique capability to
responds to different stimuli such as temperature, pH and ionic strength. They can
be used in tissue engineering, drug and cell delivery and wound healing. They
detect lesions, deliver medicine directly to affected areas, and remove tissue
samples for further study.
One of the major challenges in
developing a microrobot is to achieve motion using a very limited power supply.
The microrobots can use a small lightweight battery source like a coin cell or
can scavenge power from the surrounding environment in the form of vibration or
light energy. Microbots are also now using biological motors as power sources,
such as flagellated Serratia marcescens,
to draw chemical power from the surrounding fluid to actuate the robotic
device. These microbots can be
directly controlled by stimuli such as chemotaxis or galvanotaxis with several
control schemes available.Another
challenge, once introduced into the body, they must be able to move through
bodily fluids and tissue. Magnetic
control is used in some cases but limits the areas microbots can explore. They
have limits on motor power, motion precision, and energetic efficiency
of modules making them less relevant. Despite these challenges, microbots have
a great future. Some
scientists predict that micro robotics will define the new age after the
Internet.
