Tiny Linux Computer Has High Hopes For Robotics Apps

A computer-science professor at the University of Essex has created a novel, airborne robotics application. He's combined a $99 Linux single-board-computer, called Gumstix because it's roughly the size of a stick of chewing gum, with a motor and propeller and sent the package aloft, maintaining control via a wireless LAN connection.

"So far we've flown one fixed-wing aircraft and one helicopter," said Owen Holland, who is also the head of computer-science research at the British school. "The helicopter development has gone amazingly smoothly. It appears to be stable and it's still reasonably maneuverable. We're now concentrating on achieving visually controlled autonomous flight on a single helicopter."

As the project moves forward, Holland is looking to create a bigger buzz by building a whole a collection of flying automatons. "There are two almost independent aims: to get the helicopters to fly autonomously in the same way as a flock of birds; and to achieve Beowulf-like cluster computing using wireless," he explained. "The long-term objective is to do both at once, in an [project called] UltraSwarm."

Holland's application could be a harbinger of a wave of low-cost robotics projects spurred by the availability of the tiny Gumstix board, which appears to be gaining popularity among a home-brew and commercial users. The Gumstix board is made by a small embedded-hardware vendor of the same name in Palo Alto, Calif. Gumstix' founder Gordon Kruberg, who's long been involved in robotics, said his company is working with some 80 university robotics departments, in a bid to facilitate such projects.

He points to George Mason University, in Fairfax, Va., where a group of computer science students have set up a Wiki where they share tips on building what they call an "open" robot for about $800. Along with the Gumstix board, the robot has a servo-controlled camera, a "gripper" capable of picking up small cans, an intrusion sensor, a flat surface for pushing boxes, five infrared rangefinders to help with positioning, and a nickel-metal-hydride battery pack.

As the students use the term, "open" means they're freely sharing the design. That's something Kruberg intends to encourage. "What we are trying to do is open-source the whole concept so people who are working on robotics can start sharing drivers and applications," he said.

To extend its robotics reach, Gumstix on June 24 is planning to launch a $49 companion expansion board called "Robostix," which is intended to make it easier to control robotics peripherals. "It's a series of interfaces, control pads, and servo controls for running a robotics device," said Don Anderson, vice president of marketing at Gumstix.

In terms of technology, the Gumstix board is built around an Intel XScale processor, which is widely used in embedded systems. Though the CPU isn't an x86 device (it uses the ARM instruction set), the processor and board boast a healthy collection of software development tools.

"It comes with a Linux kernel already flashed on to it," said Anderson. "You can plug it into a Windows machine, and USB-net into it, or with Ethernet you can put it on your own network."

On the marketing front, Gumstix is taking a Dell-like approach of selling direct over the Web, in an arena where single-board computers have long been built using specialized standards such as PC/104 and marketed through distributors.

As for Prof. Holland, he's going to concentrate on the helicopter leg of the project moving forward. "We suspended work on the fixed wing project because it's almost impossible to find enough uncontrolled airspace in the UK to do it, given that the plane has a range of some 30 miles, and is very fast," Holland said.