These tiny robots can pull items 2,000 times their own weight

Scorpus

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A group of mechanical engineers from Stanford University have created a collection of tiny robots capable of pulling items more than 100 times their own weight, thanks to a clever adhesive mechanism inspired by geckos.

The feet of these small robots are covered with extremely small rubber spikes that grip onto surfaces as the robot moves. When pressure is applied to the foot, the spikes bend, which increases their surface area to provide more grip. But when the robot wants to pick up its foot to move forward, it can easily do so as the spikes will straighten.

The robot pulls heavy loads along by keeping one foot firmly attached to the surface while the other moves forward, and can do so either horizontally or vertically. One such bot weighs just 9 grams and can pull more than a kilogram, while an even smaller one weighs a mere 20 milligrams with the ability to lift items up to 500 milligrams.

But the strongest one of them all is a 12 gram bot nicknamed μTug, which has the capacity to drag an item up to 2,000 times its own weight (24 kilograms). Engineer David Christensen, a member of the team that created these robots, says that this the equivalent of a human dragging along a blue whale.

The team hopes that these sort of robots could be used for hauling heavy items around factories, or to carry items to people in emergency situations. Current prototypes are reasonably slow, as you can see from the video above, but larger robots have the potential to both be stronger and faster.

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And you shall become known as the prophet that saw it coming but failed to stop it.
 
a 12 gram bot nicknamed μTug, which has the capacity to drag an item up to 2,000 times its own weight (24 kilograms). Engineer David Christensen, a member of the team that created these robots, says that this the equivalent of a human dragging along a blue whale..

That's a bit of an exaggeration.

A blue whale weighs about 140,000 KG (go internet!) and if a human weighs 80kg (about 175 lbs) that's only 1750 times as much. Not 2000...

Anyway...you can't scale up strength at the same rate you scale up size. Strength increases on two dimensions, while volume increases on three dimensions.

So if this little thing weights 12 grams (.012 kg) and a human weighs 80kg that means the human is 6666 times heavier. and therefore, according to "engineer Dave" we would be able to drag something 6666 times heavier than the robot can drag (a blue whale weighing 159,000 kg).

But the law of scales says this isn't how it works. If something is 6666 times as massive it should only be 6666^(2/3) as strong. That means the human would be 354 times as strong, not 6666. And 354 * 24kg is 8501kg. Granted, 8500kg is a LOT, but it's only 1/18th of what he said. And considering this is a machine, the question is, could we build an 80kg machine that could drag 8500kg? I'd bet that could be easily done using an electric motor with some gears.

I'm surprised an engineer would be so far off with his math.

(source: http://hep.ucsb.edu/courses/ph6b_99/0111299sci-scaling.html
 
Think of it as the 9 gr bot being the average human, and the 12 gr uTug being a stronger than the average person, think of it as a muscle dude weighing around 120 kg (Which could make it 1166 times it's weight), above the average of the 80.

BTW when you think of rubber spikes that increase their radius it also increases it's strength not only in a rotor weight. So it could be feasible.
 
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