Imagine you've built a walking robot, and it moves reasonably well on a flat, smooth, high-traction surface... but it slides around on overly polished floors, and has trouble when the terrain is overly sloped or even if parts of the terrain are overly sloped.

Now, suppose we replace each of the feet (or perhaps just the bottoms of the feet) of the robot with a type of device called a Universal Gripper, and whenever the foot makes contact with the ground, actuate the gripper, and whenever the foot is about to be lifted up, release the gripper... or even apply positive pressure with the gripper, so that it pushes away from the ground.

Now, you're probably going to ask, "what in the world is a Universal Gripper?" It's an amazingly simple device: a rubber balloon, filled with granules, with a mechanism to suck out air from the balloon (which makes it rigid) and a valve to release air back into the balloon (which makes it soft). The more advanced version also has a mechanism to quickly blow air into the balloon, to toss away whatever had been held... or in this idea, push away from the ground a bit faster.

The Universal Gripper was invented in 2010, and has become relatively well known (if you google search for "universal robotic gripper", you'll get over 100,000 results), spread from the time of it's invention, till the present.

After it occurred to me that this kind of gripper would make awesome robotic feet (while watching a video of a walking robot whose feet were sliding around), I searched Google, and found precisely /one/ relevant result -- a one line mention, shortly after the Universal Gripper was invented. So it's not baked or half-baked, and certainly not /widely/ known to exist.
-- goldbb, Sep 14 2013

you need to shape them differently.

1: Add re-growable or replaceable hairs to take advantage of van-der-waals.

2: Shape so they deflate from outside to inside and make (adjustable-depth?) cups when fully deflated, creating suction cups

3, possibly: Add a band around (inside) where the rim of the cups will be, capable of sliding against itself to shrink or grow. This will let the cups physically grab on to any protrusions should that be helpful, or press against the sides of cracks and holes in the surface.
-- Voice, Sep 14 2013


4, possibly: rough spikes that can stick out of the middle of the pad to obtain a better grip in gels, muds, and flesh.
-- Voice, Sep 14 2013


//filled with granules//
IIRC, the early versions used coffee grounds. Good complex surfaces for the particles to grab each other (during the "suck for rigidity" phase).
(PS: "suck for rigidity" innuendo was entirely unintentional...)
-- neutrinos_shadow, Sep 15 2013


The universal gripper is dependent on the particulate forming a surface that clamps down on irregularities in the gripped object.

It won't work all that well on smooth surfaces (polished marble, glass, etc.).

Given the need for an extremely pliable outer surface, it will also be somewhat vulnerable to damage from rough/sharp surfaces. A rubberized kevlar or similar might avoid that problem, however.
-- MechE, Sep 15 2013



random, halfbakery