Graboids, a fictional species of sandworm that acts as the main antagonist of the Tremors franchise, has become quite famous among robotics engineers. This creature is often referred to as the ‘shark of the desert’.
A distinct feature of this fictional creature is they are an invertebrate species of giant worms. They are known for their digging skills and can dig big holes underground by pushing dirt and soil out of their way.
The robotics engineers at the University of California, Santa Barbara, and Georgia Institute of Technology got inspired by this fictional and dreadful creature and decided to create a robot similar to the Graboids.
The concept of this robot is similar to a snake’s body, it has abilities to crawl and burrow through soil, dirt or even soft sand. It also can bite someone. But the tester robot developed by the engineers and both the universities is quite small in size compared to the original Graboids size we see in the Tremors. This tester robot worm can dig through soil and soft sand that for now can only nibble on animals and humans.
The engineers believe that this robot due to its digging and burrowing abilities can create a blanket of debris often referred to as regolith on other planets like the moon, Saturn, earth, etc. This can be something we can expect in the next space project. These giant worms can be used as space rovers to collect samples of soil from other planets.
Nicholas Naclerio who is a graduate mechanical engineer at the University of California, Santa Barbara talked about how this giant worm has a very different digging or borrowing style. This worm will try to reduce the resistive forces while digging and will not try to fight with those resistive forces.
There are three important factors that lead to its success. First of all, it has a tip extension facility that will avoid dragging the worm through the soil along both sides of its body. This plays a key role in reducing tension while digging and does not cause wear and tear of the worm’s body.
The second feature includes air fluidization in which a granular material is converted from a solid-state to a dynamic fluid-like state. This process occurs when a fluid is passed up through the granular material. When the worm goes through the granular media which over here is the soil; sand, air fluidization occurs which leads to change in the state of the air thus helping in reducing the resistive forces.
The third feature includes asymmetry of the worm’s body which helps in controlling the lift forces. Lift forces are basically a sum total of all the forces applied to a body and force the body to move perpendicular to the direction of flow. This is avoided by the asymmetrical body of the worm which thus helps in digging horizontally.
The robot’s body is made from an air-tight fabric called ripstop nylon fabric. Often used in yachts for sails and spinnakers, hot air balloons, kites, etc as it is lightweight as well as can handle high pressure.
The body of the worm has a nylon pipe attached to it which blows air inside the worm towards its tip and helps remove the particles in front of the worm to create a route.