Prosthetic Arm Project Spins Off Next-Generation Bomb Hunter
Explosive ordnance disposal (EOD) robots have saved countless lives in Iraq. In 25,000 EOD missions, there have been 30 fatalities. The death count would have been higher if it weren't for the robots, according to the commander of the Army, Navy, and Air Force explosives disposal teams in Iraq. But "improvements can be made and should be made," he said at a National Defense Industry Association (NDIA) Ground Robotics Exposition.
A small group of engineers from the Biomedicine Business Area was already heading in that direction with the creation of the Dexterous Robotics Platform. The system, affectionately known as Sally, is a fabricated human torso "armed" with the first two prototypes from the Revolutionizing Prosthetics Program, an APL-led effort to create a prosthetic arm that looks, feels, and operates like a human limb. Much of Sally was developed under APL's Independent Research and Development (IRAD) funding specific to Biomedicine.
To operate Sally's arms, controllers slide their arms into exoskeletal sleeves and insert their hands into gloves with sensors on the fingertips. The operator can control the robot's movements by simply moving his own limbs. The robot is mounted on a two-wheeled platform that can be steered by a video-game-type controller, a joystick, or a foot-controlled pressure sensor worn in the operator's shoes.
It is topped off with a tracking and visualization system—two networked cameras spaced at the same separation and gaze angle as human eyes—that streams images to two eyepiece screens mounted in a visor-like cap. An operator not only sees what Sally sees, but when he moves his head, Sally's follows.
Matthew Kozlowski, a National Security Technology Department engineer working on the effort, describes Sally as "unlike any of the traditional EOD platforms. Most fielded EOD robots are racked vehicles with very low dexterity and a claw that can move in three, maybe five ways. Sally has stereo vision. The operator can see what she sees in 3D. She has motion-tracking features that allow the neck to pan with the operator's movement. And her limbs can fully mimic the operator's motion."
EOD personnel should be able to learn the system quickly, Kozlowski adds, "since we already innately know how to control our native limbs. The system will serve as a significant milestone in anthropomorphic mobile robotics and as a test bed for operator training and development." The Navy, the lead service in developing EOD robots, asked APL to create a common system architecture for the next generation.
"APL already has the expertise to support this role, in advanced robotics research, human system integration capabilities, virtual integration environments, and platform autonomy," Kozlowski says. "But as the technology advances, we will begin using it as a test bed for the control architecture and other advanced robotics tasks, and it will eventually be a cross-enterprise Lab resource."