Lasers give rise to spider robots for dangerous missions

Ashley N. Paddock, ashley.paddock@photonics.com

Chemical spill? Gas leak? Mine collapse? Send in the spiders.

Laser-based 3-D printing can help fabricate mobile robot spiders that can explore environments considered unreachable by or too hazardous for humans.

The prototype robot, developed by researchers at Fraunhofer Institute for Manufacturing Engineering and Automation IPA, looks and moves much like a real spider. With a camera and measurement equipment onboard, it can provide emergency responders with images on the scene of a chemical accident and even offer data about poisonous substances. And as does a real spider, the device keeps four legs on the ground at all times, rendering it able to navigate any terrain.

The researchers used selective laser sintering (SLS) to shape the plastics for the prototype, combining rigid and elastic shapes in a single component. They applied step-by-step thin layers of a fine polyamide powder and melted them into place with a laser beam to create the robot’s complex geometries, inner structures and lightweight components.

A robotic spider could help emergency responders obtain information about chemical spills and other dangers. Images courtesy of Fraunhofer IPA.

All components required for motion, such as the control unit, valves and compressor pump, are located on the robot’s body. It can carry a variety of sensors and measuring devices, depending upon the appliction. Hinges interoperate with bellows drives to pneumatically bend, extend and turn the artificial limbs as needed.

Using SLS saves materials, minimizes assembly effort and reduces the time it takes to build the spider, said Ralf Becker, a scientist at Fraunhofer. He added that individual parts can be quickly swapped and, because the robot is so easy and cheap to produce, it can be discarded after just one use.

The robot spider’s legs are 20 cm long. Elastic bellows drives serve as its joints.

The robot spider also could be useful for exploration and search-and-rescue missions; for example, after natural catastrophes and industrial or reactor accidents. It also could help responders to fires by broadcasting live images or tracking down hazards or leaking gases.

The prototype was displayed at the recent EuroMold 2011 show in Frankfurt, Germany.