January 14, 2023: After decades of incremental improvements in UGVs (unmanned ground vehicles), Estonia and South Korea recently delivered UGV models that troops find useful, dependable and easy to operate. The most recent (late 2022) is the South Korean Arion-SMET (Autonomous and Robotic systems for Intelligence Off-road Navigation – Small Multi-purpose Equipment Transport). Arion is a 6x6 version of a 2019 4x4 UGV that was adequate for civilian uses but not for the more dangerous and demanding military operations. A major improvement for the 2022 Arion is the vehicle software, particularly the autonomous capabilities and ease of use for operators. Hanwha, the developer and manufacturer, has been developing UGVs since 2006 and created lots of incremental improvements in UGV design.

Arion can carry up to 550 kg (1,100 pounds) of cargo or accessories. The primary use is battlefield transport of ammunition and other supplies as well as evacuation of casualties. Additional vehicle equipment turns Arion into a reconnaissance vehicle which can also call-in artillery fire or airstrikes. Standard equipment includes gunfire detection that quickly locates where gunfire is coming from. Arion can also be armed with a machine-gun controlled by a remote operator or autonomously. The navigation system can follow a specific nearby operator (“follow the soldier”) or autonomously find its way to a location. An onboard diesel generator charges the batteries which, on a full charge, enable Arion to travel up to 100 kilometers. Max road speed is 43 kilometers an hour while it is 34 kilometers offroad.

A similar UGV, THeMIS, was developed by an Estonian company and entered service in 2020. Several NATO nations adopted it and in late 2022 some were sent to Ukraine where they performed so well that the Russians tried to capture one and steal its tech. Russia has been developing UGVs for a long time but is way behind other nations when it comes to software and tech. As of early 2023, Russia is still seeking to grab a THeMIS.

THeMIS is a tracked 1.6-ton UGV with a remarkably effective sensor system that enables it to find its way through any terrain. It is a compact vehicle measuring 2.4 meters (7.8 feet) long, two meters (6.6 feet) wide and 1.15 meters (3.75 feet) high. In contrast the heavier two-ton 6x6 wheeled Arion vehicle is 2.95 meters long and 1.5 meters wide.

THeMIS also uses a diesel generator to recharge UGV batteries. When operating, electricity is used for propulsion for five or more hours of continuous use. THeMIS has a 1.2-ton payload, which can consist of cargo, casualties, more sensors or even weapons. Top speed is 20 kilometers an hour but it normally moves at a walking pace. At least ten NATO members have evaluated THeMIS and most then purchased THeMIS. Ukrainian troops were pleased with its performance and asked for more. Unlike Arion, THeMIS has been used in a combat zone.

Israel and the United States have become the major developers of UGVs. The Americans have been at it for about two decades and the Israelis even longer than that. Israel has been facing continuous military and terrorist threats since the 1940s, so its UGVs are often used in hostile environments. Israeli firms like Roboteams regularly introduce new UGV models. While Roboteams has only been around since 2009, it continued decades-old Israeli efforts to create more useful UGVs. In 2021 Roboteams introduced the Rook, a 6x6 UGV similar to the South Korean Arion. Rook is a 1.2-ton 6x6 vehicle that can carry 1.2 tons of equipment and operate up to eight hours using a hybrid (generator/battery) motor. Max speed is 30 kilometers an hour and it can be towed by other vehicles at up to 80 kilometers an hour. An operator can control several Rooks simultaneously using the Torch-X software that allows an operator to control any ground, aerial or seagoing autonomous vehicle equipped to work with Torch-X. There is also a ruggedized tablet with a seven-inch display that just controls ROOKs within a thousand meters of the operator.

While UGVs come in all sizes and perform a wide variety of tasks, one of the most popular uses is logistics, i.e., carrying supplies or equipment in a combat zone. ROOK’s predecessor, the smaller (435 kg) 4x4 Probot, was successful because it did that well and was able to operate successfully for border security along the dangerous Gaza border. Manned patrols are sometimes fired on or attacked by bombs placed near the security fence. Attacking a Probot carrying a load of day/night sensors, including one that can detect the direction gunfire came from, made border patrol safer and more effective. For decades Israel has been using various models of UGVs for this and, as new tech appears, the next models of UGV incorporate it. Probot and Rook are examples of this.

There has long been a demand for military logistics UGVs, that are easier to use and more robust (works effectively and reliable most of the time). These vehicles are meant to operate on roads or paths which have been checked out by humans.

The 4x4 Probot originally weighed 410 kg (900 pounds) and carried up to 700 kg (1,500 pounds) or one stretcher casualty. Probot does not have true autonomous operation but instead uses sensors to avoid immediate obstacles and GPS to go from one waypoint to another, or it can simply follow a man on foot guiding it to its destination. For this there is also a follow the leader (vehicle in front) capability. The lead vehicle can be a manned one carrying a small electronics pack for the following Probot to follow. This wireless link can be up to 500 meters. Top speed is 9.6 kilometers an hour (six MPH). This is suited for the nastiest terrain and a man-on-foot leading the vehicle or vehicles. It is battery operated and operates eight hours before needing a recharge. This is an improved MULE UGV that the Americans canceled a decade ago. Probot is a much better UGV but it is unclear if it is better enough to gain enough sales to be profitable and worth continuing to produce. In 2017 Probot V2 was introduced. This version weighed 435 Kg with a max payload of 750 kg, Top speed was now 12 kilometers an hour and max range of the wireless controlled 700 meters.

Efforts to develop usable large military UGVs have so far been energetic and prolific, but unable to create vehicles ready for battlefield use. The only ones useful enough to generate large orders and widespread use are the small UGVs. By 2011 Americans had developed and the military deployed the second generation: XM1216 SUGV (Small Unmanned Ground Vehicle). This is a 13 kg (29 pound) robot, like the slightly larger Packbot that demonstrated the concept could work five years earlier. SUGV can carry 3 kg (6.6 pounds) of gear, and one of seven different "mission packages." These accessories include various types of sensors and double jointed arms (for grabbing things.) SUGV is waterproof and shock resistant. It fits into the standard army backpack and is meant to operate in a harsh environment. The battery-powered SUGV is operated wirelessly, or via a fiber optic cable, using a controller that looks like a video game controller with a video screen built in. SUGV can also use an Xbox controller, with the right drivers. Like the older PackBot, SUGV can climb stairs, maneuver over rubble and other nasty terrain.

The SUGV design was based largely on feedback from combat troops. For example, it is rugged enough to be quickly thrown into a room or cave and begin sending video, as well as audio, of what is in there. This feature makes it very popular with the troops, who want droids with the ability to see, hear and smell more acutely. No one likes being the first one going into a dark, potentially dangerous, place. Throwing a grenade at first doesn't always work, because sometimes frightened civilians are in there. But the current generation of robots are not fast enough, agile enough or sensitive enough to compete with human troops doing this kind of work. Sometimes, however, the robots are an adequate, and life-saving, substitute. SUGV is supposed to be better at this sort of thing.

SUGV can also perform outpost and listening post work. These are two dangerous jobs the infantry are glad to hand off to a robot. Outposts are, as the name implies, one or two troops dug in a hundred meters or so in front of the main position, to give early warning of an enemy attack. A listening post is similar, but the friendly troops are often much deeper into enemy territory. The SUGV battery enables it to just sit in one place, listening and watching, for eight hours or more. After that, you send out another SUGV with a fresh battery and have the other one come back for a recharge. No risk of troops getting shot at while doing the same things over and over, and the troops really appreciate that. Again, the problem with this is that the robot sensors are just not there yet. Getting close, but not close enough for troops to trust their lives to this thing.

Other dangerous jobs for the SUGV are placing explosives by a door (to blow it open for the troops), or placing a smoke grenade where it will prevent the enemy from seeing the troops move. For nearly a decade before SUGV appeared, users of older small UGVs filled military message boards with interesting uses they had found for these robots, and new features they could make use of. SUGV was the product of all that chatter.

Because SUGV became available after most of the heavy combat in Iraq and Afghanistan was over, sales were minuscule. There were still a lot of the older, and still useful, Packbots available. Sales of these UGVs to police department bomb squads became a major source of sales. If SUGV had shown up eight years earlier it would have sold in huge (thousands of units) numbers. After 2011 there simply was not enough demand, especially because so many older UGVs were good enough.

Larger UGVs are having an even more difficult time finding customers willing to buy them in quantity. For example, in 2011 the U.S. Army canceled all versions of its MULE (Multifunction Utility/Logistics and Equipment) robotic vehicle. In 2010, it canceled the transport and mine clearing versions. A year later the remaining version (Armed Robotic Vehicle-Assault Light) was canceled, and development work on MULE ended. Meanwhile, work was already underway on a smaller design, called MUTT (Multi-Utility Tactical Transport) that learned much from the MULE project and produced the MUTT UGV that entered service in 2021.

MULE was one of these futuristic concepts, a robotic vehicle for carrying stuff on the battlefield. In practice, it did not work out. Close, but not close enough. MULE was a one ton, six-wheeled vehicle that is 4.8 meters (15 feet) long, 1.93 meters (six feet) wide, which carried nearly a ton of equipment or weapons. The operator (any infantryman with an hour or so of training) used a handheld controller to tell the MULE to go from Point A to Point B. The MULE has enough computing power to get over obstacles it can handle and go around those it could not.

The MULE was designed to handle a lot of dangerous jobs normally requiring troops, like bringing supplies (ammo, water, weapons, or medical supplies) across that last few hundred meters, to where the fighting is going on. Currently, that means troops hauling this stuff themselves, and exposing themselves to enemy fire. The MULE could also take casualties far enough away so a medevac helicopter could take over. MULE could also be equipped with mine clearing equipment, to perform another dangerous job. MULE was also to be equipped with heavy weapons (.50 caliber machine-gun, small autocannon, or missiles), that would be fired under human control.

The troops were eager to have something like the MULE around, if only because it makes their life in the combat zone so much easier and safer. The MULE was designed to take a lot of damage and keep going, but only actually using it in combat would reveal what its weaknesses were, and what modifications had to be made. MULE never got that far because field tests were disappointing. MULE was canceled in 2011. Development continued and by 2015 Son of MULE showed up as the smaller 750 kg MUTT that can carry up to half a ton of cargo. The MUTT design was a lot more flexible and came in 4x4, 6x6 or 8x8 models that could also be equipped with tracks.

After 2001 the U.S. Army suddenly had, for about a decade, more money, and freedom to use it, than it ever expected. A lot of useful stuff was developed, often by simply modifying civilian gear. That also worked with small UGVs. Thus encouraged, by 2005 the army put UGV development into high gear, to get more UGVs (unmanned ground vehicles) into the hands of the troops. That worked as between 2005 and 2010, thousands of small UGVs used by American troops for checking out caves and buildings were put into service and the troop response was very positive. Some of these lightweight (under 45 kg /100 pounds) robots were even equipped with weapons, but not used much when armed.

The army hoped that the next major development in UGVs would be heavier, weighing 1-3 tons. That's where the much-anticipated MULE came in. As more gadgets are invented for the troops, the weight they must carry keeps increasing. One solution was believed to be a UGV that can accompany troops, carrying a lot of this load, otherwise, each soldier is going to be carrying about 45 kg (100 pounds) of gear, which is hardly “fighting weight.” There’s one problem, a major one, and that was the building of a sensor/software system that would allow the MULE UGV to move along the ground without a human driver. This proved to be a major obstacle, although developers of driverless car systems have demonstrated in the last decade, progress is still being made and that eventually led to MUTT.

Meanwhile, there are already civilian robotic security systems that use UGVs. But their software moves a vehicle around a known course, with limited navigation ability, and only enough smarts to alert a human operator that the droid has encountered something that is not supposed to be there. A combat UGV that will be allowed to decide when and where to fire is now possible. But there is a reluctance to build them and turn them loose.

The Israelis have been working on the larger UGVs and had a very real need for them because they had hundreds of kilometers of borders in remote areas that were threatened by hostile intruders. These borders were already patrolled regularly by troops in ATVs (all-terrain vehicles), often the Israeli made Tomcar ATVs. In 2006 an Israeli firm produced a robotic vehicle based on the two-seater TomCar. Called AvantGuard, the robotic vehicle used sensors and software that enabled it to patrol along planned routes, and was capable of some cross-country operation as well. The designers knew that improved sensors, software and computers would improve capabilities. The AvantGuard mounted a remote-controlled gun turret equipped with a 7.62mm machine-gun. The vehicle had digital cameras facing every direction and used pattern recognition to identify potential threats, like people sneaking around where they are not supposed to be, or obstacles on the road. The idea was that a pair of human operators could control a dozen or more AvantGuard vehicles. This system was particularly effective at night because it had night vision and moved quietly. Weighing only 1.3 tons, the AvantGuard was protected against rifle fire and fragments from shells and smaller roadside bombs. AvantGuard proved adequate for guarding industrial parks, but not the vast stretches of Negev desert, along the border with Gaza. Too many things could go wrong out in the desert (obstacles in the road, hostile action) that AvantGuard could not handle. Despite, or because of actual field testing in border and combat zones, the IDF (Israeli Defense Forces) and border guard concluded that, while promising, AvantGuard was not worth purchasing. Not yet, but eventually. Work continued and in 2008, building on the AvantGuard technology, Guardium appeared. Using the same TomCar vehicle, and a remote-control turret, the Guardium has better sensors and software. Guardium was pitched as "smart" enough to be used in urban areas and to serve as an emergency response vehicle. Guardium proved effective along the Gaza border, where Palestinians were constantly trying to cross the border, either for economic gain or to kill Israelis. Guardium eventually got better sensors, giving it better hearing than humans and a navigation system like those now used by driverless cars. Guardium was so successful that it was able to use its autonomous (not always monitored by a human) mode a lot more. This was largely because of the improved sensors and software that had been improved over several decades to accurately detect what is out there. Despite impressive prototype vehicles Guardium never obtained enough orders to keep the project going and the project shut down in 2016.

The Israelis kept trying. In 2017 the Rambow UGV appeared. While Rambow did not attract buyers, it was a definite improvement on predecessors. About the same time the first Probots were demonstrating the ability to deliver on many of the feature’s troops have been seeking in a battlefield logistics UGV. In addition, Probot/Rook can also be equipped with a wide variety of combat zone equipment and use it under fire, which is something the troops always appreciate. At the same time the failed American MULE evolved into the smaller, more capable and MUTT. Probot and Rook found buyers in the United States and other countries. The MUTT has also attracted foreign customers. The demand is out there for UGVs that can reliably carry payloads autonomously. For Israel such vehicles are a matter of life and death and need is constant and continuous. That’s why even the less successful UGVs found work in Israel. American UGV developers followed Israeli progress in this area and developed smaller UGVs that met an urgent need for Western armies that have overloaded their infantry with useful new gear that has the troops, and their commander, desperately seeking a solution to carrying all that useful stuff into the combat zone without exhausting the infantry. Rook and MUTT are not the final word in UGVs that do their job, but demonstrate the worth or continuous improvement of the tech.