The Slithering Robot Tries to Worm Its Way Into Navy's Tactical Units

By DAVID VERGUN
Associate Editor

Snakebot is a developmental model of a slithering robot that might one day help remove land mines or worm its way inside collapsed buildings to help rescue victims without disturbing the tottering structures. RoboLobsterr is the prototype for a possible future fleet of many-legged unmanned underwater vehicles (UUVs) designed to hunt and destroy mines in shallow water.

These are two of dozens of experimental systems based on the characteristics of sea organisms that the Navy is evaluating. Navy scientists are searching for innovative ways to design robotic vehicles that can take on more of the services' most dangerous and difficult jobs.

Robots, or unmanned vehicles, already handle many surveillance duties for Marine Corps units, and the Navy is well into the development of the UCAV, an unmanned combat aerial vehicle being designed to carry out air strikes against enemy targets by the year 2020. But scientists at the Office of Naval Research (ONR) in Arlington, Va., believe future robots could perform many more complex tasks.

Civilian and naval scientists at ONR are studying the behavior and properties of barnacles, bats, bees, and a broad spectrum of other critters to determine what benefits they may bring to future Navy programs.

Blue Lights and Fruit Flies

Snakebot, developed for ONR at Carnegie-Mellon University in Pittsburgh, Pa., is a snake-shaped robot five centimeters in diameter and equipped with gears, which enable it to slither, and sensors that enable it to carry out a variety of underwater tasks. Phillip Abraham, an ONR science officer, said that, in addition to land-mine removal and victim rescue, slithering robots also might aid in the structural inspection and repair of Navy platforms.

The coral reefs that line many of the world's littorals are made from tiny living sea creatures that secrete calcium carbonate, the substance that forms the reefs. Interestingly, this substance is fluorescent, and glows in several bright colors when illuminated with blue light. Steven Ackleson, ONR's program manager for environmental optics, believes that the Navy would be able to locate sea mines and other objects more easily in a reef environment by illuminating the sea floor with blue lights, separating the man-made objects, which do not fluoresce, from the coral reef itself.

Bats use echolocation both to search for food and to navigate in the dark. ONR hopes to improve the Navy's radar capabilities by mimicking the echolocation capabilities of large brown bats, which can immediately detect and classify the size and shape of a beetle flying 30 feet away. Neurons in the bat's auditory system are being studied to determine how bats can sense an object's shape as well as the distance and direction of objects in the bat's radarscope. Harold Hawkins, an ONR science program officer, said that Navy electronic sonar-processing systems can differentiate objects between echoes about 12 millionths of a second apart, but bats can differentiate objects 2 to 3 millionths of a second apart.
High-lift biorobotics research at ONR is focusing on ways to make UUVs and unmanned aerial vehicles (UAVs) both more stable and more maneuverable in turbulent air and sea conditions. As part of this effort, ONR scientists are studying the hawk moth, fruit fly, bird-wrasse fish, and boxfish to determine how they achieve high lift quickly and with greater stability--as well as less heave, pitch, yaw, torque, and drag--than is possible with man-made systems. The boxfish can turn on a dime, fruit flies recover from delayed stalls and can land upside down, hungry hawkmoths stay on target (even in mid-air) while feeding, and bird-wrasse fish, using only their pectoral fins, propel their bodies forward at incredibly high speeds. Current ONR research is focused primarily on the neuromuscular systems of these animals in an effort to better understand--and later copy--their amazing propulsion capabilities.

Two studies of lobsters are being conducted. First, ONR is examining the spiny lobster's acute sense of smell, which gives it the ability to sniff out many odor trails in cloudy, turbulent water, according to Keith Ward, chair of ONR's Biomolecular and Biosystem Science and Technology Group. Ward said he believes the Navy could use such olfactory information to enable UAVs and UUVs to smell chemical weapons in the air and unexploded ordnance in shallow waters. Scientists are examining the lobsters' sniffing sensors--antennae as well as hairs--and neuron connections to the brain.

The second lobster study focuses on the ability of lobsters to use their legs to maneuver in all directions in turbulent shallow water. The goal here is to mimic the lobsters' deftness of movement on legged UUVs that could hunt and destroy mines in shallow water. A prototype has already been constructed.

Many other animal initiatives are ongoing at ONR, including efforts to: install tentacles on UUVs and UAVs that would mimic the sensitive and flexible arms of an octopus; design a virtually inexhaustible supply of microbial fuel cells from plankton that could supply electricity to UUVs; build an improved infrared combat camera that mimics the eyes of the infrared-sensitive honey bee; and create an unmanned surface vehicle that copies the desert scorpion's ability to negotiate rugged and extremely hot terrain.

Chief of Naval Research Rear Adm. Jay M. Cohen told a seminar audience at the Navy League's 2003 Sea-Air-Space Exposition that ONR's science and technology research is a worthwhile investment essential to the development of systems that will be vital to U.S. national security 15 or 20 years down the road.

Animals will play a pivotal role in at least some of that research. *