As we continue to explore other planets, we're going to want to know not only what's on their surface, but also what's underneath it. That's where the Mole-bot comes in – it's a robot that autonomously tunnels its way through the ground.
Developed at the Korea Advanced Institute of Science and Technology (KAIST), the Mole-bot is inspired by both the European mole and the African mole-rat. The latter excavates tunnels by biting into the earth with its strong incisor teeth, while the former uses its powerful forelimbs to push dislodged soil back behind itself.
Instead of mole-rat-like teeth, the Mole-bot has a sort of propeller-like expandable drill in front. As this whirls around and grinds its way into the soil, its folding serrated blades extend outwards to dig a tunnel that's wider than the robot's cylindrical body. Next, instead of forelimbs, the bot uses two extendable hinged metal flanges located on either side of the drill to push the loose soil back past its front end.
The drill and the flanges operate alternately, so that they don't get in one another's way.
Three caterpillar-like tracks in the rear push the Mole-bot forward, plus a pivoting mechanical "waist" in its midsection allows it to change direction while tunnelling. It's able to orient itself utilizing 3D Simultaneous Localization and Mapping (SLAM) technology, which continuously tracks the robot's location relative to the Earth's magnetic field.
Along with its use on other planets, the Mole-bot might also be utilized in the mining industry. As compared to existing drilling systems, it is claimed to be cheaper, less labor-intensive and more eco-friendly, as it doesn't require mud compounds in order to clear debris. The current prototype, which is the third version of the robot, measures 84 cm long by 25 cm wide (33 by 9.8 in) and weighs 26 kg (57 lb).
"We look forward to a more efficient resource exploration with this type of drilling robot," says the lead scientist, Prof. Hyun Myung. "We also hope Mole-bot will have a very positive impact on the robotics market in terms of its extensive application spectra and economic feasibility."
You can see it in action, in the video below.
And for another example of an autonomous tunnelling robot, check out the worm-inspired BADGER.
Source: KAIST
