A new minuscule robot just four millimetres in size could potentially be used in the future for minimally invasive surgery and targeted delivery of medication into the human body. It is a so-called soft robot, a robot built from soft materials inspired by living organisms.
The robot has been developed by scientists at Germany's Max Planck Institute for Intelligent Systems. The tiny soft robot is able to move around easily in complex environments - both on dry surfaces and in a liquid - which the scientists say makes it unique. For example, the robot can walk, crawl or roll over uneven terrain, carry a load with it and swim in liquids.
Inspired by small-bodied animals with one-week bodies
Scientists were inspired to develop the robot by larvae of beetles, caterpillars and jellyfish. "We looked at the physical locomotion mechanisms of both week-bodied caterpillars and jellyfish and took inspiration from this. As a result, our millirobot is a combination of different small animals with week bodies, such as the larva of a beetle, a caterpillar, a spermatozoid and a jellyfish," said Professor Metin Sitti, director of the Physical Intelligence Department at the Max Planck Institute for Intelligent Systems in Stuttgart.
The robot is controlled using magnetic particles embedded in the robot's body, which is made of soft elastomer. If these magnetic particles are exposed to external magnetic fields, the robot's body changes shape. This not only allows the robot to be propelled, but also, for example, to change direction and make the robot jump.
Delivering drugs to desired location
"In the future, our robot can transport medications and deliver them to the desired location where they are most needed," said Sitti, drawing comparisons with delivering a parcel to the front door. The robot can be 'released' into the human body by swallowing the robot or letting it enter the body through an opening in the skin. The robot can then be sent to the desired location in the human body via the digestive tract, urinary tract or abdominal cavity, among others.
The robot has already been tested is an artificial surgical model of the stomach and tissue of a chicken. Sitti's team, consisting of Wenqi Hu, Guo Zhan Lum and Massimo Mastrangeli, managed to successfully guide the robot to its destination in both cases using external magnetic fields. By using ultrasonic imaging technology, the scientists were able to track the robot's movements during this procedure. Sitti hopes the robot will one day become a standard in healthcare, enabling non-invasive access to hard-to-reach areas of the body. "Currently, many small regions in the human body cannot be reached without surgery. Our goal is to reach these regions non-invasively and perform diagnostic or therapeutic procedures with our soft robots," Sitti said.
More information can be found at the scientific journal Nature, which published a paper by the scientists.
Author: Wouter Hoeffnagel
Source: Max Planck Institute for Intelligent Systems (pictured)
Source: Nature
