Robot caterpillar can deliver drugs inside human body

Beijing, Sept. 27: Scientists have developed a tiny, soft robot with caterpillar- like legs that can carry heavy loads and could be used to deliver drugs in the human body.

The robot developed by researchers from the City University of Hong Kong ( CityU) can move efficiently inside surfaces within the body lined with, or entirely immersed in, body fluids such as blood or mucus.

The robot has hundreds of pointed legs, measuring less than a millimetre. Researchers studied the leg structures of hundreds of ground animals, including those with 2, 4, 8 or more legs, in particular the ratio between leglength and the gap between the legs.

“Most animals have a leg- length to leg- gap ratio of 2: 1 to 1: 1. So we decided to create our robot using 1: 1 proportion,” said Shen Yajing, an assistant professor at CityU, who led the research.

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, making the leg- length- to- gap ratio around 1: 1.

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. — PTI