Sandia Hand – low cost robotic arm for bomb dismantling

Robotic hands are regarded as one the most complex parts of the robotic system. Complexity due to many joints and embedded sensors, combined with need to maintain their light weight and dexterity, lead to high prices of robotic hands. Researchers at Sandia National Laboratories managed to develop a modular and affordable robotic hand meant to disarm improvised explosive devices.

The Sandia Hand is modular, thus allowing different types of fingers or attachments to be connected with magnets and quickly plugged into the hand frame. The operator has the flexibility to quickly and easily attach additional fingers or other tools, such as flashlights, screwdrivers or cameras. Aside allowing flexibility of the system, modularity allows easier maintenance and prolongs the durability of the system. The fingers are designed to fall off in case the operator accidentally clashes the hand into a wall or some other object.

“Rather than breaking the hand, this configuration allows the user to recover very quickly, and fingers can easily be put back in their sockets”, said Curt Salisbury, principal investigator of the project at Sandia National Laboratories. “In addition, if a finger pops off, the robot can actually pick it up with the remaining fingers, move into position and re-socket the finger by itself.”

The operator controls the robot with a glove, and the lifelike design allows even first-time users to manipulate the robot easily. The robot’s tough outer skin covers a gel-like layer to mimic human tissue, giving the Sandia Hand the additional advantage of securely grabbing and manipulating objects, like a human hand.

Using Sandia’s robotic hand to disable improvised explosive devices, rather than blowing them up, could preserve the evidence of bomb construction and lead investigators to the bomb makers themselves.

Sandia partnered with researchers at Stanford University to develop the hardware and worked with consulting firm LUNAR to lower the cots of the hand. In current commercially available robotic hands, each independently actuated degree of freedom costs roughly $10,000, leading to robotic hands that cost between $120,000 and $250,000.

“The Sandia Hand has 12 degrees of freedom, and is estimated to retail for about $800 per degree of freedom — $10,000 total — in low-volume production. This 90 percent cost reduction is really a breakthrough”, said Salisbury.

DARPA is funding a separate software effort in a parallel track to the hardware work. Although it is initially developed for bomb dismantling, the low price and advancements in the design of the robotic hand developed at Sandia Labs could one day be used as a base for artificial arms for people with disabilities or for people recovering from injuries.

“At this price point, the Sandia Hand has the potential to be a disruptive technology”, said Philip Heermann, Sandia senior manager. “Computers, calculators and cell phones became part of daily life and drastically changed how we do things when the price became affordable. This hand has the same potential, especially given that high-volume production can further reduce the cost.”