Students and researchers at Stanford University have developed a new kind of robot that explores its environment in a totally new way. The caterpillar-like robot, made of soft material, can stretch over long distances without moving its body. This makes the robot very suitable for all kinds of applications, such as rescue operations in the rubble of a collapsed building.
The robot is shaped like a small, airtight cylinder. It looks like an inflatable rubs but the design is a lot more ingenious than that. The mechaniscm of the robot is based on natural organisms that cover distance by growing, such as plants and nerve cells.
Folded into itself
The basic idea behind this robot is a tube of soft material folded inside itself, like a sock sitting inside out. The robot grows in a certain direction as the material at the front of the tube pushes outwards. This process can continue endlessly.
It is this unique growth mechanism that makes this robot so useful. "The body of the robot lengthens once the material extends at the end but the rest does not move," said Elliot Hawkes, lead author of the study. "If the robot gets stuck, say between two rocks, the robot does not stop. The end can keep growing as long as new material is added."
Obstacles
Tests with different prototypes have shown good results. Among other things, the researchers let the robot loose in a set-up with all kinds of obstacles. In doing so, it had to manoeuvre over sticky paper, glue, between nails and along an ice wall. The robot also showed it could crawl through a hole much smaller in diameter than itself and lift a 100-kilogram crate off the ground by crawling underneath.
The researchers have developed a software system that determines the robot's direction based on pictures coming in through a camera on the front of the tube.
The scientists think the robot will be useful for a variety of applications. They are thinking primarily of natural disasters. For example, the growing robot can manoeuvre itself through debris with a little camera on the front allowing rescuers to see even in unreachable places. It could also carry with it a sensor that detects carbon dioxide emissions from survivors. Because the robot is made of soft material, it is much safer to use around people than hard robots.
Furthermore, they see future potential for medical applications (such as examining the gut) or pulling cables through small spaces.
Further research
Although the Stanford team is happy with the initial results, further research is still needed. They are also working on an advanced form of the robot. In the prototypes, handmade from cheap plastic, the researchers used compressed air to grow the robot. In the future, they want to create a version that can be made automatically. It may also be possible to grow the robot using liquid.
Furthermore, the researchers are looking at the possibilities of stronger materials such as nylon and Kevlar and much smaller and larger versions.
By: Kelly Bakker
Source: Stanford University
