Tech Focus: Robotics
Army evaluates robots for big EOD dig
The Army Environmental Command tested a variety of familiar robotic systems Feb. 10 at Fort Bliss, Texas. Several of the systems have already seen action in the United States and overseas in removing explosive ordnance devices (EODs), improvised explosive devices (IEDs) and unexploded ordnance. But the Army has a much bigger job in mind for these systems.
“What makes our testing here at Fort Bliss different is that we're trying to apply this equipment to support future range construction activities, which require a lot larger areas to be cleared,” said Gene Fabian, range sustainment program manager at the Army’s Aberdeen Test Center.
“We're looking at what's going to work and what we can scale up to address the larger capacity — or the larger volumes of soil that might be required to be processed for a range-construction activity as opposed to some of the smaller scale EOD range maintenance activities that they've typically done with this equipment,” Fabian said.
The Air Force Research Laboratory (AFRL) produced several of the systems tested from commercial technology, which the lab customized only slightly.
As a result, Fabian said, it’s easier and cheaper to convert equipment for remote operations. “In earlier versions there was a lot of custom building for a remote package. Now it's almost completely off-the-shelf.”
One of the AFRL-built systems was the All-Purpose Remote Transport System (ARTS), a remote-controlled, lightly armored tractor that handles and disarms explosives. The Air Force developed ARTS to dismantle or disable IEDs, partly in response to the Khobar Towers bombing in Saudi Arabia in 1996, according to the AFRL’s Materials and Manufacturing Directorate.
Two other systems from AFRL also were evaluated. One is a remote-controlled excavator with a sieve for sifting dirt for fragments and smaller shells. The other is the Advanced Mobility Research and Development System (AMRDS), an autonomous robotic vehicle for towing geophysical sensors that detect buried metal objects.
The AMRDS “is set up for autonomous operation, meaning that we plug in the outer boundaries of an area that we will want geophysically surveyed,” said Robert Selfridge, chief geophysicist at the Army Corps of Engineers at Huntsville, Ala. The result is a complete map of all the metallic anomalies in an area before and after cleanup, he said.
The evaluation focused on two issues, Fabian said. One was removal efficiency — that is, the percentage of metallic anomalies on the range that can be removed with robotic systems. The other was whether the rate of the work could be accelerated through these systems to help meet schedules.
The Army is evaluating robots for the range-clearing job because of the danger and costliness posed by other options: clearing by hand or using armored, manned vehicles.
“The remote-operated equipment that we're demonstrating helps us remove that risk because the operators are outside of the blast zone,” Fabian said. “Hand-digging is very expensive. The second option would be use of armored equipment, but you have limitations on the size of rounds that you can armor against. Above [75 millimeters in size], you have problems not only with the fragmentation generated but also the pressure weight would kill somebody in" the equipment.
“Part of that analysis is how much we can reduce schedule by, because the range-construction schedule is very accelerated and very ambitious,” Selfridge said.
Although the Fort Bliss robotics demonstrations proved generally successful, “one of our tasks that became very evident during this demonstration is that everything has to be much larger scale for these very large, vast areas that we have to clear with a very limited amount of time,” Selfridge said.
In practical terms, that would mean adapting the ARTS, a Bobcat-sized vehicle, into one more on the scale of a Caterpillar bulldozer for some brush-clearing operations. The size of the excavator also would need to be increased to sort large quantities of earth. And the autonomous-scanning unit, which Fabian said works basically like a robot Zamboni, would need to cover larger areas more effectively.