US Army Maneuvers Supply Convoy with Driverless Trucks

If you happened to have been in Texas last year, visiting the US Army's massive military reservation at Fort Hood, you might have noticed a convoy of three driverless Army trucks being put through its paces in different, simulated, real-world environments known in military parlance as a Joint Capabilities Technology Demonstration.

Then again, you might not have noticed anything at all, since the convoy's behavior wasn't noticeably different from ones where the human drivers are behind the wheel. That was part of the idea. There's been a lot of talk recently about military robotics, armed drones and reconnaissance systems, and how disruptive they will be on future battlefields. But it's possible the biggest disruption, and benefit, might come from the rear with unarmed, unmanned supply convoys.

Within military history circles there is a saying that “amateurs study tactics while professionals study logistics.” Battles may be won by infantry and tank divisions, but unless there is a good supply stream supporting them, their victories will likely prove short-lived. For this reason, most armies have truck and transportation fleets that are as large, if not larger, than their inventory of tanks and armored vehicles. The US Army is no exception.

Being a truck driver for the US Army is no easy job. During both the Afghanistan and Iraq wars, supply lines were usually very long, traveling through remote territories where the roads were rough and the turns sometimes tight and badly graded. Convoy missions could go ten, even fourteen hours. And with the ever-present threat of enemy ambush or roadside IEDs (improvised explosive devices), drivers and crews needed to constantly maintain high levels of situational awareness. But even so, there were attacks and there were driving accidents. Despite best efforts, collisions and rollovers occurred, as did injuries and lost lives.

With all this in mind, it couldn't have been difficult for the US military's logistics chiefs to accept the case for having automated-driving systems aboard its trucks. The savings ADAS promises in terms of manpower, materiel, operational cost, and most importantly, human lives, is hard to ignore. The real question is whether automated driving systems can be made to work in the kinds of adverse driving conditions that military truck convoys typically face.

TARDEC, the U.S. Army's Tank Automotive Research, Development and Engineering Command, along with defense contractor, Lockheed Martin, is currently road-testing a kit-based automated-driving system it developed. It’s called AMAS, and it can be retrofitted onto different vehicle types that make up the Army and Marine Corps' massive logistics fleets.

It provides a scalable automated driving capability that ranges from warnings and driver assistance to full-up driver-less operation. AMAS, or Autonomous Mobility Appliqué System, consists of two separate, interfacing sub-kits. The By-Wire kit provides an active safety and control interface, while the Autonomy kit provides the robotics.

“What we did is develop a kit that could be applied to a variety of military vehicles,” says David Simon, AMAS program manager for Lockheed. “We installed them on seven different vehicles and we've performed a series of capability demonstrations during the last two years to provide some look at how they perform in different environments including urban areas.”

In leader/follower systems such as AMAS or the system currently being tested by Volvo Trucks, the individual vehicles must 'know' everything about their surroundings and position, while they take directions from the lead vehicle. They use onboard equipment and sensors such as radar, lidar, GPS, computer vision and inertial technology. Advanced control systems interpret sensory information to identify appropriate navigation paths.

AMAS' By-Wire Kit provides active safety and control interfaces for steering, braking, transmission and engine functions, along with lane keeping, collision warning and rollover prevention. The Autonomy Kit provides the convoy capability, allowing the vehicles to operate in either a leader or follower mode, along with waypoint navigation and features for obstacle detection and avoidance.

While the systems in the Autonomy Kit are mostly military systems, the By-Wire Kit consists almost entirely of commercial, off-the-shelf components. According to David Simon, this was what TARDEC's planners stipulated when the system was first being devised: “The sensors that we used all came from the commercial automotive world.”

This is not to say, however, that information coming out of them was exactly the same as on civilian vehicles. Simon says, “We needed to gather a bit more sensor data from the radar used in the adaptive cruise control. But because we have a relationship with the suppliers, we can get more data out.” Simon wouldn't identify any of the manufacturers involved except to say they were all well-known Tier One companies.

Simon explained the two-system approach used in AMAS this way: “We're relating to the environment in which the vehicles will be working. Lane keeping as developed in a commercial system will not always work on a dirt road. The mission profile is not always the same. The military is going to decide what capabilities it wants beyond what the commercial systems provide.”

Although the ultimate goal may be to have trucks that can perform full-up convoy supply missions without having human drivers aboard, currently all tests are being done with a human in the cab capable of taking over vehicle operation at a moment's notice. AMAS is being developed to meet a joint Army-Marine requirement. The one difference is that the Marines want an access port on the side of the cab into which a PlayStation-type controller can be plugged so that a Marine, walking alongside one of the AMAS-equipped can guide it in to a berthing position when being loaded onto a ship for transport.

AMAS recently completed its Joint Capabilities Technology Demonstration–the first involving three driverless trucks at Fort Hood, and the second, involving nine, which was held at the Savannah River Site in South Carolina. They are now awaiting a decision from TARDEC on continuing the program.

“A decision is imminent,” says Simon, though he wouldn't say when he expected it would be made. But when it does, he says there is a clear transition path in place.

Bernard Theisen, Technical Manager for AMAS at TARDEC, believes AMAS has wide-ranging possibilities. “At Fort Hood, we demonstrated driverless trucks obeying rules of the road while interacting with drivers and pedestrians in a complex urban setting. We've also been successful in demonstrating high-speed line haul operation with a convoy of seven vehicles. We've been able to show different types of vehicles working in unison, using commercially-available sensors and vehicle-to-vehicle communications. The driver-less vehicle is coming both in commercial and military applications and the Army is at the forefront of this technology.”

Find out how the latest autonomous tech is impacting the automotive world at TU-Automotive Detroit 2015 (June 3-4).

Autonomous Vehicles