Researchers at NASA's Jet Propulsion Laboratory, Pasadena, Calif., have created a micro robot reminiscent of the childhood character Charlotte from "Charlotte's Web." Dubbed "spider-bot" for its spider-like appearance, this itsy-bitsy, high-tech critter may one day chart the terrain on other planets and explore smaller bodies, such as comets, asteroids or the Moon.

The spider-bot prototype. Photo: NASA/JPL

Spider-bots may also help with maintenance and repairs on the International Space Station. On Earth, they might fill in for humans by investigating hazardous materials or taking soil measurements on farms.

"Traditional rovers have very efficient wheels, but there are things we'd like to explore with legs that you can't do with wheels," said Robert Hogg, engineer in JPL's Mobility Systems Concept Development Section. "Our aim is to make a small, capable robot that can explore varying terrain in different environments; in other words, go anywhere any time."

Like a real spider, this robot has feeler-like antennas, which help it detect various obstacles. The first prototype is small enough to fit in the palm of your hand. Future versions could be one-tenth that size. Equipped with cameras that pan and survey its surroundings, the spider-bot has six legs and uses a tripod-walking gait to balance while in motion. In the future, depending on the kind of work they must perform, spider-bots may have eight, 12 or even 50 legs.

Hogg led the team of researchers developing the micro robot, which recently underwent its first demonstration. Small radio packages were dropped from a larger rover, and one radio was turned off. A spider-bot was successfully directed to navigate simulated Martian terrain to take the place of the "broken" radio.

Spider-bot prototype and JPL engineer Robert Hogg. Photo: NASA/JPL

Researchers envision multiple spider-bots weaving an entire communications network without the need of an existing infrastructure, such as a satellite. Each robot would continuously collect data from the environment and transmit the information short distances from one spider-bot to the next. The data could be shared by all of the spider-bots, allowing each one to know what is collected elsewhere.

Development of the spider-bot is true to NASA's vision to create evolvable hardware with many uses. "In the old days, if one instrument failed an entire mission might be at risk," said Dr. Neville Marzwell, manager, Advanced Concepts and Technology Innovations at JPL.

"The new approach is to have structures or robots that are reconfigurable, adjustable and flexible to stand on their own," Marzwell said. "Evolvable, reconfigurable structures are key to changing the paradigm for future space missions by increasing their functionality while reducing cost by becoming a multi-use robot or system."

The next big step in the development of the spider-bot is for researchers to attach tools to the robot's two front legs, enabling it to perform tasks like digging and repair. They also plan to build a more advanced prototype that will move faster, climb and make independent decisions to explore. "In the future, we might use a hundred or a thousand of them at once, so they can all work together to achieve one goal," Hogg said.

NASA's Cross Enterprise Technology Development Program provided funding for this work. The California Institute of Technology in Pasadena manages JPL for NASA.