City University in Hong Kong is developing a milli-robot that can travel throughout the human body, through blood, mucus or dry terrain, and administer drugs or perform a medical inspection. The robot is so small it will likely be undetectable by the patient. The design is similar to a caterpillar, and was chosen specifically to be able to travel throughout the many different kinds of pathways in the human body.
“The robot's body thickness measures approximately 0.15 mm, with each conical leg measuring 0.65 mm long and the gap between the legs measuring approximately 0.6 mm,” Eurek Alert reports. “Moreover, the robot's pointed legs have greatly reduced their contact area and hence the friction with the surface. Laboratory tests showed that the multi-legged robot has 40 times less friction than a limbless robot in both wet and dry environment.”
The tiny legs are a key part of the design, making the robot much more capable in diverse environments. Professor Wang Zuankai at City University notes, “The rugged surface and changing texture of different tissues inside the human body make transportation challenging. Our multi-legged robot shows an impressive performance in various terrains and hence open wide applications for drug delivery inside the body," says Professor Wang.
The robot also has an incredible strength, as laboratory tests show it is capable of transporting 100 times its own weight. This strength is “comparable to an ant,” or more perhaps more relatable, it is as if “a human being [was] able to easily lift a 26-seated mini-bus,” Eurek Alert calculates.
“The amazingly strong carrying capability, efficient locomotion and good obstacle-crossing ability make this milli-robot extremely suitable for applications in a harsh environment, for example delivering a drug to a designated spot through the digestive system, or carrying out medical inspection," adds Dr Shen of City University.
The next step in development is to be able to smoothly decommission the milli-robot after it has fulfilled its task. "We are hoping to create a biodegradable robot in the next two to three years so it will decompose naturally after its meds delivery mission," says Dr Shen.