By Derhun D. Sanders, Tank Automotive Research, Development and Engineering CenterAugust 2, 2011
DETROIT ARSENAL, Mich., Aug. 2, 2011 -- Unmanned ground vehicles allow warfighters to perform surveillance, route clearance and threat defeat from safer distances. Tele-operation makes it possible for warfighters to maintain even greater standoff distances while conducting these dangerous tasks.
New technology developed by the U.S. Army Tank Research, Development and Engineering Command's, or TARDEC's, Tank and Automotive Research Center may make it possible to perform these missions at an even greater distance, possibly far from the battlefield.
The military currently operates unmanned aircraft systems, or UAS, in theater but can control them from the United States. This has proven very effective in Iraq and Afghanistan, so in May 2010, the Tank Automotive Research, Development and Engineering Center's Ground Vehicle Robotics, or GVR, team undertook an initiative to determine whether unmanned ground assets could be similarly controlled.
"While UAS are flying in theater, they're being controlled from here," remarked GVR Robotics System Integration Laboratory Electrical Engineer Ty Valascho. "Our task within GVR was to see if we could get that capability working and be able to drive it using all in-house assets."
TARDEC's Long Distance Tele-Operation, or LDTO, system allows operators to access a secure Web portal and log into the system. Miles away, the UGVs have already been dialed-in. Once connected, the operator selects a platform from a drop-down menu and is directed to a user interface screen that includes a variety of commands and a video link with the platform.
The robot is operated through the Internet using a cellular data signal.
Directional Associates worked with the original equipment manufacturers to get interface information about the fielded robotic platforms, which enabled the LDTO capability to be integrated onto UGVs. The system has been demonstrated with the TALON, PackBot and Omni-Directional Inspection System platforms.
"One of the constraints we put on ourselves was that we wanted to use whatever systems they were using in theater because it would make the transition to the field easier," Valascho stated. "Because these were largely commercial-off-the-shelf robots that had been rapidly fielded, the government had no technical data packages on the platforms. So that was a big challenge. We had to work with that supplier to get some information. They were very helpful, but it took a few months to get that information."
GVR associates also worked with academic partners through the Ground Robotics Research Center, or GRRC, to design a secure Web portal that allows users to log into the system and operate the systems over the Internet.
"We made the design choice early on to use a cellular data link, so securing that equipment, getting the appropriate approvals and working it through the configuration control board all took some time and effort," Valascho explained. "Michigan State University and Wayne State University, who partner with us through the GRRC, assisted us with setting up the secure website, and once we had that, we were able to begin the challenge of getting the system to work."
While operators have successfully used LDTO to control UAS in theater, ground assets face obstacles that aerial platforms do not.
"When you're flying in open space you can move in any direction at any time. As long as you're staying above a certain height, the odds of running into another aircraft are really slim," Valascho commented. "Airspace is pretty tightly controlled, and you don't really have random aircraft running around."
"On the ground, none of that is true. UGVs have mobility challenges going down slopes, moving up slopes and watching out for obstacles on the ground that they can't overcome or that could overturn them. Those are all things that a UGV operator has to be aware of that someone driving an air asset doesn't," he continued.
While video cameras allow operators to see oncoming hazards, the use of unpredictable Internet connections and data feeds poses significant challenges.
"If the robot's moving at full speed and you're trying to negotiate around something, even a half-second delay can make a huge difference," Valascho noted. "Latency is a problem, and the fact that we're going over the Internet adds another challenge, because it's not constant latency. This is a variable latency, so sometimes the delays are very great and sometimes there's very little delay. We're trying different techniques to minimize the effect on the user."
As the team continues to address latency, they are also developing a user interface that is easy to use, yet still allows the full range of platform capabilities. Currently, a common basic interface is used to control all platforms.
"There are several refinements we're making to the user interface," Valascho remarked. "Because these are complicated systems, we have a balance to strike between making the interface easy to use while still allowing them to have all of those platforms' capabilities. We're working with experts at the Army Research Laboratory who know a lot about user interface, and we've received several helpful suggestions."
Testing at TARDEC's Warren, Mich., facilities and other locations has proven that LDTO of UGVs is possible.
"We first got it working in August 2010," Valascho remarked. "We've conducted end-to-end testing from Fort Benning, Ga., and Selfridge Air National Guard Base, Mich. Our engineers have reduced latency by slightly redesigning the system. I think we have latency down as far as we can get it now, so we're looking to see what we can do to compensate."
Valascho believes that the work done by TARDEC could serve as a foundation for future fielded applications.
"If this were to be a fielded solution, there would have to be a lot of redesign because we would use military satellites and would be doing things a lot differently," he commented. "Right now, we're just showing what's possible, but there are big parts of the system that could be reused if this were fielded."
These capabilities could provide life-saving assistance to Soldiers, allowing them to complete missions while removed from harm's way.
"Driving a robot professionally is a specialized skill; it isn't something that just anybody can do. Our warfighters are very valuable people, so we try to reduce the amount that they're put into harm's way," Valascho concluded. "I think this would be a very big benefit for the Army in terms of reducing risks to these valuable assets."