Soldiers' missions frequently lead them to locations where they must assess the status of structures, and where the presence of threats is not immediately known or easily detectable. These threats include everything from ambushes to chemical and biological threats that could be lurking around every corner. Current technology assists soldiers in detecting these possible threats by allowing them to assess structures and threats through the use of teleoperated sensing systems.

Army researchers envision the use of spatially distributed, multimodal, wide- field sensing based on the neurophysiology of insects for enabling navigation and obstacle avoidance on micro aerial robots. (Photo: U.S. Army)

"Think of it as a camera on wheels, where soldiers have a one or two pound sensor that they can throw into a building to assess situational awareness," said Dr. Brett Piekarski, chief of the U.S. Army Research Laboratory's Micro and Nano Materials and Devices Branch within the Sensors and Electron Devices Directorate, or SEDD; and Cooperative Agreement Manager of the Micro Autonomous Systems and Technology, or MAST, Collaborative Technology Alliance. "The soldier controls it like a video game to complete the task."

Though successful in getting the job done, current systems have their drawbacks. "In order for soldiers to send a system into a building and guide it along the way, they must put their weapons down to do so. This creates the need for other soldiers to stop what they are doing to protect the solider that is controlling the system," Piekarski said.

In addition, existing sensing systems do not have the ability to go everywhere the soldier goes because they are not very successful in rugged terrain and are too slow to keep up with the speed of the soldier. According to Piekarski, in terms of the future, sensing systems are desired that have the ability to find their own way in and out of a structure, instantaneously send back information to the soldier from within the structure, hover to defend soldiers' perimeters and perch to conduct surveillance, all while being minimally monitored by the soldier.

A key benefit of future systems is that they would allow soldiers to complete other tasks, including keeping their weapons readily available for self- protection. These systems can come in the form of ground vehicle sensors, aerial sensors and humanoid robots that would work hand-in-hand with soldiers, creating what Piekarski calls a "bubble" around them for sensing and protection purposes. The U.S. Army Research Laboratory, known as ARL, is working toward providing improved situational awareness capabilities for soldiers through projects that involve small unmanned aerial vehicles, and insect scaled platforms.

Researchers are currently working with the ARL microquadrotor, which is a platform for testing integrated sensing and processing on size-constrained robotic systems. The system is currently able to fly using a manual pilot control or within a test environment that utilizes an external visual tracking system, such as a Vicon system. According to Dr. Joseph Conroy, research engineer in SEDD, the sensing integrated onto this iteration of the vehicle provides limited capabilities for sensing the environment.

"Methods currently used for control, navigation and obstacle avoidance, such as laser range finders, are prohibitively heavy and expensive. We wish to use methods inspired by the neurophysiology of the insect visual system to provide these capabilities within the necessary payload," Conroy said. He noted that soldiers have expressed a desire for general purpose squad level Intelligence, Surveillance and Reconnaissance capabilities that can be provided by flying robotic vehicles, however, they wish to minimize weight, training required, and time spent paying attention to the robotic system instead of the environment around them. "For this reason, these vehicles must demonstrate a high degree of autonomy in a small package," he said.

In terms of insect scaled platforms, ARL researchers are developing and testing millimeter-scale robotic leg structures. According to Dr. Ronald Polcawich, team lead for Piezoelectric-Micro Electro-Mechanical Systems Technology at ARL, the leg structures consist of segments of piezoelectric thin film actuators and thin film copper sections that are designed to mimic the kinetics of a leg and have the ability to move, lift and resist impact.

Amidst the benefits that these future systems could offer, foreseen challenges do exist. "One of the challenges of future systems in being a true teammate to the Soldier involves joint decision-making and the trusting of information," Piekarski said. "Soldiers can become fatigued after long hours on duty, whereas systems are more consistent, but soldiers may be able to see better first-hand if something appears to be a threat or not. We are currently examining how soldiers will ultimately make their decisions. Will they trust their instinct, the system, or a combination of both?"

Through the challenges to be faced and the development and testing of these future technologies, the goal of Army researchers remains the same — to extend the situational awareness of soldiers in order to provide them with advanced protection on the battlefield that could help save their lives when they are put in risky and unknown situations.

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