Microscopic Robots in Healthcare
In the wake of the current pandemic, healthcare is at the top of everyone’s list, including that of the robotics industry. Robots have started to advance in almost every industry, however, the medical industry will be the pinnacle of bio-robotics.
What is MedTech?
MedTech refers to the union of the technology and medical industries. In Silicon Valley, the shift of focus towards MedTech is all but apparent. However, whenever MedTech is discussed, the question always arises of how the robotics industry can possibly be a part of something that is as far from technology as it is possible to get?
The answer to this question lies, not in the large but in the small. When it comes to truly helping people live healthier lives, microscopic robots are the clear solution. As fantastical, and yet scientifically possible, these small surgeons are, creating these robots is much harder than it looks.
A lot of the advancements in the microscopic world of robotics are still within the boundaries of research. The main problem these researchers are attempting to solve is that of locomotion. How can we make these robots move around the body? There are several approaches, ranging from mechanical to magnetic, to even chemically powered robots.
Cornell University’s Walking Robots
Recently, a team of researchers at Cornell University lead by Dr Mark Miskin, Itai Cohen, and Paul McEuen developed walking microbots that can be controlled by lasers. These robots are so small that you could fit 10 of them in the full stop at the end of this sentence.
The robots are made up of a body covered in solar cells based on conventional electronics, along with 4 platinum legs. The legs are moved using microscopic actuators (motors), which are controlled through lasers. This laser control is so precise that the team was able to move an entire army of these walking robots in simultaneous motion.
So far, all the microbots that have been developed used some sort of abstract methods such as magnetism or chemical control to move. The reason why these walking robots stand out from the rest is that they are in fact made up of conventional electronics and are moved just like electric cars are. This enables us to create smarter versions of these robots where someday they might even be able to move all on their own.
Bradley Nelson, a scientist at ETH Zurich, has created microbots that work very similarly to bacteria and use changing magnetic fields to move around the body. These researchers took inspiration from shape-changing bacteria and used origami techniques to make the microbots do the same, allowing them to effectively move around the body.
Nelson’s microbots use two things to move – a magnetic field and a shape-changing body. The robots are made of sensitive chemical materials which change shape based on the viscosity and temperature of the environment around them. This enables it to get around tight spots and navigate human tissue.
The robot then draws power from the changing magnetic field to propel itself forward. The team has tested this technology using a simulated oesophagus and stomach. The parts were 3D Printed from silicon in order to consistently simulate the real body. The robot was able to successfully move through the apparatus, demonstrating that this hybrid control system can indeed work as expected.
Researchers at MIT have created a similar pill that can be ingested and then unfolds inside the body. Under the influence of a magnetic field, this pill can also move around the body and deliver chemicals to specific parts of the body.
Chemically Powered Robots
The main concern that comes up with the methods of propulsion described above is that they may not be biocompatible. The adverse effect of essentially ingesting electronics into the body is something that people are unsure of. This is why researchers are also exploring more biocompatible means of chemically powered robots.
There is much research going on about creating microbots that use harmless chemical reactions using readily available resources within the body (such as water and oxygen), in order to propel themselves forward. One of these research groups has developed a microbot that can propel itself around the mouth to fight biofilm (Dental Plaque) developments on teeth.
These researchers have developed a chemical system that can carry out a simple chemical reaction in order to propel itself forward. The system takes H2O2 (Hydrogen Peroxide), as its reactant and decomposes it into H2O and O2. This simple reaction creates little oxygen bubbles that propel the system in the opposite direction.
This type of “bubble propulsion” is not only useful in dentistry but in many other treatments as well. This is because it allows doctors to send special chemicals and medicines to targeted areas within the body, leading to the most efficient treatment. In the case of dental plaque treatment, these microbots have the ability to penetrate through the plaque within 5 mins.
What’s next for Microbots?
There is much scope for this technology in the near future. So far, we have robots that can propel themselves with the help of external forces such as lasers or changing magnetic fields. However, without the help of these external devices, these robots have nowhere to go and are rendered useless.
The next generation of microbots will have the ability to move on their own and select a path or area to target. These robots will be pre-programmed with instructions on what medicines to deliver to specific parts of the body and they should be able to carry out these tasks autonomously.
The walking robots developed by Cornell University’s research team, have opened the doors to this exact possibility. Since the walking microbots are created using conventional silicon chip technology, their electronics can be expanded to include preprogrammed microscopic logic gates which will enable them to move without the help of a guiding laser. With the advent of this technology, the dream of autonomous microscopic robots is not so farfetched after all.