MIT’s CSAIL (Computer Science and Artificial Intelligence Laboratory) has released the announcement of a tiny ingestible robot, designed to be swallowed and sent to perform tasks within the human body. The robot is the newest in a series of programmable matter robots known as “origami robots”, so named because of their ability to fold themselves into different shapes.
The origami robot completely unfolded (left) and in a partially-folded state with an embedded magnet (right). Image courtesy of MIT.
These programmable matter robots are able to change shape based on pre-installed creases in the semi-rigid material they’re constructed out of. By inputting different algorithmic electrical signals, the robots’ shape-memory alloys are able to assemble themselves into different shapes without being physically touched.
The robots activate and unfurl when exposed to heat. They are then controlled via “external programmable actuation”. In other words, the robot is controlled by programmed magnetic fields generated externally. This is made possible by a small magnet folded into the programmable material.
Dissolvable Pig Intestine Casing
According to MIT’s CSAIL Director Daniela Rus, the rather simplistic list of materials needed to build these origami robots means that they’re significantly cheaper to manufacture than their traditional robotic counterparts.
But over the past year, the team has had to tackle issues that inherently come with putting foreign material, in this case tiny robots, into a human body. As Rus puts it: “The challenge with designing an ingestible robot is finding biocompatible materials.
The solution in this instance has been to base the programmable material on dried pig intestine material— the same sort of pig intestine used in sausage casings.
The pig intestine material is water soluble and bio-compatible, making it easier for human digestive tracts to process and expel it.
Application in the Medical Field
The hope is for these miniature robots to be able to deliver medicine to specific points of the human body and even patch internal wounds.
At present, however, the magnets in the newest origami robots lend themselves to a specific and important medical task: removing swallowed batteries.
Button batteries are commonly swallowed by children and, if allowed to remain in the body, can cause erosion in stomach and esophageal linings.
This new pig-intestine-based variation of the origami robot is promising for its prospective ability to drag wayward batteries into the the digestive tract. Despite how invasive it sounds to have a programmable material robot in one’s stomach, this robot is being designed to merely be swallowed and excreted.
An origami robot still partially encased in an ice pill demonstrates how it can magnetically grab onto a swallowed battery. Video courtesy of MIT.
Once ingested, the robot will be manipulated (via external magnetic fields) into workings its way to the swallowed battery. Once it’s dragged said battery safely to the correct point in the digestive system (where it can be harmlessly processed), the robot will dissolve and be excreted along with the battery it was sent to collect.
Because the robots unfurl when exposed to heat, the current plan is for them to be swallowed when encased in a pill made of ice. This will ensure that the robots only unfold (and then refold) once they’ve reached a patient’s stomach.
The next steps, Rus says, are to develop and attach sensors to the origami robots so that they can control their own actions instead of relying on instruction from an external magnetic field.