Interview with Prof. Metin Sitti, Department of Physical Intelligence, Max Planck Institute for Intelligent Systems, Stuttgart
Robotics open up countless new possibilities for medical technology. Especially highly miniaturized robots could be increasingly used in minimally invasive surgery in the future. Researchers at the Max Planck Institute for Intelligent Systems have developed a mobile millirobot, which is able to move smoothly through rough terrain. They were mainly inspired by the world of insects.
Prof. Metin Sitti
In an interview with COMPAMED-tradefair.com, Prof. Metin Sitti explains how the millirobot developed by his team works, what it is used for and why the use of such robots offers many advantages for minimally invasive surgery.
Prof. Sitti, what inspired you to build the robot?
Prof. Metin Sitti: We looked at the physical mechanism of locomotion of soft-bodied caterpillars and jellyfishes and took inspiration from them. The result is that our millirobot is a mix of small-scale soft-bodied animals, such as a beetle larva, a caterpillar, a spermatozoid, and a jellyfish.
How do you control the robot?
Sitti: We use an external magnetic field. Magnetic particles are embedded in the polymer layer of the soft robot. In this way, its larval-like shape can be changed from the outside. We can use these shape changes to control where the robot moves. For example, it can move on surfaces or on wheels. It can also overcome obstacles, crawl through narrow tubes or even swim in liquids. It is also capable of capturing, carrying and storing objects at a certain destination.
What exactly will the Millirobot be used for in the future?
Sitti: In the future, our robot can carry drugs and deliver them to a desired location where they are most needed, much like a doorstep delivery. We would use it for minimally invasive medical applications inside the human body: it would be delivered through swallowing or a cavity on the skin and make its way through the digestive or urinary tract, abdominal cavity, or heart surface.
The millirobot is very small with a size of four millimeters.
What is particularly innovative?
Sitti: The Millirobot has a very high mobility. It can also move easily in a complex environment - including surfaces as well as liquid media. The robot is also very small with a size of four millimeters, flat and made of soft, elastic polymer. Since it can easily change its locomotion mode, it also comes quickly from the spot in rough terrain. It is an intelligent robot, but its intelligence is not based on "computational intelligence" - the built-in computing power - but on its physical nature. The materials it is made of, its ability to organize and adapt itself make it unique.
In many areas of the body, we can currently not gain access without surgical intervention. Our goal is to use our soft millirobot to gain access to these regions in a non-invasive manner, in order to be able to make a diagnosis and carry out a therapy.
What challenges still need to be overcome in order to establish the robot in medical technology?
Sitti: At present, there are still some challenges to be overcome before these kinds of systems can establish themselves in medical technology. So far, we have only been able to test the robot in a synthetic gastrointestinal model and animal tissue. This environment allowed us to control the softrobot very well. With the help of ultrasound, we were able to follow the robot's path and check exactly where it could make its way. Further tests are still pending.
What are the plans for the future?
Sitti: For minimally invasive surgery, the use of mobile robots could represent a revolution. Such a millirobot allows surgeons direct access to areas of the body that are otherwise difficult to access. In addition, this type of robot can be controlled and monitored very precisely in the body. Due to all of these advantages, miniaturized soft robots could become a standard feature of medical technology in the future.
The interview was conducted and translated from German by Julia Unverzagt.