Stanford Team Developing Spiked Robots To Explore Phobos

cylonlover writes "Robot hedgehogs on the moons of Mars may sound like the title of a B-grade sci-fi movie, but that is what Stanford University is working on. Marco Pavone, an assistant professor in the Department of Aeronautics and Astronautics, and his team are developing spherical robots called 'hedgehogs' that are about half a meter (1.6 ft) wide and covered in spikes to better cope with rolling and hopping across the surface of the Martian moon Phobos with its very low gravity."

I don't get it

[Dunbal]

How does reducing the actual surface area in contact with the ground help it stay on a moon with low gravity? Or are the "spikes" expected to sink into the "dust" or something? What happens when this thing drives over a rock?

Re:I don't get it

[DiamondGeezer]

The problem with low gravity is low friction. So in order to drive across a body with low gravity, you need to increase the effective coefficient of friction (or increase the mass, which makes it more expensive to get there).

In answer to your second question, you keep the speed down.

On the other hand if you need to jump across something, then just a little boost will do it...