December 18, 2002
This is not the kind of bug you want to squash. The new Spiderbot is the leggy brainchild of JPL's Mobility Systems Concept Development section, including two ambitious engineering students and one recent graduate. Gabe Sibley, Jonathan Wall and Michael Poole spent their summer vacation building and testing this robotic hexapod.
Sibley, a doctoral research student in the Robotic Embedded Systems Laboratory at the University of Southern California, has long been interested in robotics. As a child, he got his start building with Legos and tinkering in his father’s machine shop. Poole, a mechanical engineering graduate of Southern California also spent a great deal of time in the machine shop while growing up but didn’t seriously consider a career move into the field until his junior year and subsequently got a job in the USC Robotics Research Laboratory. Wall, a Caltech senior, had his sights set on JPL “way back” in high school all the way from Portland, Oregon. Seemingly surprised that he has already reached that goal, he is now considering furthering his education at Carnegie Mellon University.
After JPL engineer Robert Hogg asked them to join the team, they were given the daunting challenge of building a working, micro-legged robot in a matter of weeks. Over a two week period Poole used a powerful computer-aided drafting program to produce 3D geometric models of the ‘bots body parts that would later be rapid-prototyped from a plastic epoxy. Three days after finishing the final drawings, the individual parts they ordered arrived at the lab and they began assembling the new creation almost as if it were a kit from the local hobby store, building it with the eagerness of children, Poole said.
Although they might look like child's toy, the size of the Spiderbot is not a novelty. Small robots can be incredibly useful in exploring Earth and space. However, engineers are often tasked with providing them enough computing power to accomplish complicated tasks. The current spider-bot operates on limited power.
"The electronics system, which coordinates the Spiderbot’s legs and monitors its sensors, is only about 1 centimeter square (less than a square inch)," Wall said. "It’s enough for basic walking around, but a lot of sensor technologies involve algorithms that simply require more computational power."
After assembly, the group was challenged with exploring mobility and sensor options.
"We take guidance from nature," said Sibley, the team's technical lead. "For example, animal locomotion gives us design clues and can show us how to improve overall energy-efficiency."
By mimicking biological features, the young engineers hope to increase the capability of the Spiderbot. With expanded computational power, the team could integrate an Inertial Measurement Unit which functions as an inner ear for the 'bot, using gyroscopes and accelerometers to maintain balance. They also hope to incorporate shape memory alloy nanomuscles, or tiny artificial muscles, that would give it the ability to grasp and move objects. An artificial "skin" with solar arrays could allow the spider-bot to remain "on" all the time by constantly absorbing and regenerating power.
"Future options for the Spiderbot will greatly increase its ability to perceive its environment," Wall said. "We hope to provide the brains and brawn needed to be truly autonomous."
These small wonders are proving that bigger isn't always better. Their size and mobility promises to lend them to important tasks that would be impossible for larger robots or for humans.
"At disaster sites, a number of spider-bots could get into the area and quickly establish an information network that would relay information back to rescue workers," Sibley said. "For planetary missions, astronauts could have a deployable information web, on-hand, to relieve them of tedious tasks."
As young as they are, these three seem to know that their future is in robotics. They are clearly at home in the lab having found a career track that suits them and a place that fosters their interest in the field. And aside from the benefit of working with leading robotics experts at JPL, another important perk Poole noted is the opportunity to collaborate in a campus-style environment with such a strong academic atmosphere and they don’t even have to wear a tie.
Contacts: JPL/Colleen Sharkey (818) 354-0372