Why Can't Cars Move Like Crabs Physicists Create Insect-imitating Robot To Scoot Over Unstable Surfaces

Thu, 4 Feb 2010

If you've ever gotten stuck in mud or sand in your car, you know that our cars, trucks and SUVs don't always do what we need them to. But now there's a smoother way for us to get around all the bumps, holes and curves that come our way.

They're a big attraction at aquariums, giant spider crabs that can grow to the size of a car and can travel over all kinds of surfaces. But what if physics could make a car that moves like these crabs?

He attaches backpacks onto the crabs, which are connected to strain gauges that measure the movement of its legs. High-speed video tracks other animals, like lizards, as they run.

"We're interested to explore how the motion of the limbs and the motions of its little pointy feet allow mobility on certain types of sand but not very high mobility on other types of sand," says Dr. Goldman. Scientists are also measuring how different forces impact unstable materials, setting the stage for devices that can move better through them.

A robot, designed by engineers at the University of Pennsylvania, is based on a common cockroach and can be programmed to walk through deep sand. A mini-vehicle designed to move like an insect.

The army is helping to fund Dr. Goldman's research. The hope is that by learning more about the physics of unstable surfaces, scientists and engineers can develop vehicles for the military that are more adaptable to sandy deserts and other environments. One thing physicists and engineers do know -- the way we think of motion is changing, one step at a time.