A Robomedic for the Battlefield

A snakelike robotic arm may one day medically attend to soldiers as they are carried off the battlefield.The first 30 minutes after a battlefield injury are dire: that's when nearly 86 percent of battlefield deaths occur. Before attending to the wounded, frontline physicians have to quickly locate the casualty and extract him from the battlefield, often under heavy fire. This can take up costly minutes, as well as expose medics themselves as possible targets.

Now researchers at Carnegie Mellon University (CMU) are developing technology to give battlefield medics a helping hand--literally. Howie Choset, an associate professor of robotics at CMU, has engineered a snakelike robotic arm equipped with various sensors that can monitor a soldier's condition. The robot can be wirelessly controlled via a joystick, so that a doctor at a remote clinic may move the robot to any point on a soldier's body to assess his injuries as he's being carried to a safe location. The robot's serpentine flexibility allows it to maneuver within tight confines, so that, in case a casualty can't be extracted from the battlefield immediately, the robot can perform an initial medical assessment in the field.

Choset and his colleagues have been building "snakebots" for over 10 years, improving range of motion and flexibility, as well as minimizing the overall size in multiple prototypes. In the past, the group has designed robots for urban search-and-rescue missions, and has worked with Ford Motor Company to build snake robots for precise auto-body painting. The team recently formed a startup company to commercialize one of its latest technologies, a robot that can potentially perform heart surgery.

Currently, the team is collaborating with the U.S. Army's Telemedicine and Advanced Technology Research Center (TATRC) to integrate the robotic arm within the military's high-tech stretcher, called the Life Support for Trauma and Transport system (LSTAT). This stretcher is essentially a portable intensive-care unit, with a ventilator, defibrillator, and other physiological monitors, and it's currently being used in areas of Iraq and Afghanistan. Medics can quickly load a casualty onto the stretcher and attend to injuries with the equipment onboard.

"It has all these sensors onboard so we can perform preliminary diagnostics and maybe therapeutics to save the guy's life," says Choset. "The problem is, these sensors are attached to the LSTAT, and you would have to move them by hand, and if someone's shot and you go over and help them, you're an easy target. So we want to automate this whole system, and robotically move the sensors onto the patient while he's being dragged off the battlefield."

The Army's Remote-Controlled Beetle

The insect's flight path can be wirelessly controlled via a neural implant.

Cyborg beetle: Shown here is a giant flower beetle carrying a microprocessor, radio receiver, and microbattery and implanted with several electrodes. To control the insect’s flight, scientists wirelessly deliver signals to the payload, which sends electrical signals through the electrode to the brain and flight muscles.A giant flower beetle with implanted electrodes and a radio receiver on its back can be wirelessly controlled, according to research presented this week. Scientists at the University of California developed a tiny rig that receives control signals from a nearby computer. Electrical signals delivered via the electrodes command the insect to take off, turn left or right, or hover in midflight. The research, funded by the Defense Advanced Research Projects Agency (DARPA), could one day be used for surveillance purposes or for search-and-rescue missions.

Beetles and other flying insects are masters of flight control, integrating sensory feedback from the visual system and other senses to navigate and maintain stable flight, all the while using little energy. Rather than trying to re-create these systems from scratch, Michel Maharbiz and his colleagues aim to take advantage of the beetle's natural abilities by melding insect and machine. His group has previously created cyborg beetles, including ones that have been implanted with electronic components as pupae. But the current research, presented at the IEEE MEMS in Italy, is the first demonstration of a wireless beetle system.

The beetle's payload consists of an off-the-shelf microprocessor, a radio receiver, and a battery attached to a custom-printed circuit board, along with six electrodes implanted into the animals' optic lobes and flight muscles. Flight commands are wirelessly sent to the beetle via a radio-frequency transmitter that's controlled by a nearby laptop. Oscillating electrical pulses delivered to the beetle's optic lobes trigger takeoff, while a single short pulse ceases flight. Signals sent to the left or right basilar flight muscles make the animal turn right or left, respectively.

Most previous research in controlling insect flight has focused on moths. But beetles have certain advantages. The giant flower beetle's size--it ranges in weight from four to ten grams and is four to eight centimeters long--means that it can carry relatively heavy payloads. To be used for search-and-rescue missions, for example, the insect would need to carry a small camera and heat sensor.

In addition, the beetle's flight can be controlled relatively simply. A single signal sent to the wing muscles triggers the action, and the beetle takes care of the rest. "That allows the normal function to control the flapping of the wings," says Jay Keasling, who was not involved in the beetle research but who collaborates with Maharbiz. Minimal signaling conserves the battery, extending the life of the implant. Moths, on the other hand, require a stream of electrical signals in order to keep flying.

The research has been driven in large part by advances in the microelectronics industry, with miniaturization of microprocessors and batteries.