The Avtonomnyy Razvedyvatel'ny Tank, shablon 2151 (2151-pattern Autonomous Reconnaissance Tank) is a light mechwalker used by military and civilian authorities in Mechanocratic Russia. It sees service in the Mecharussian Armed Forces, often alongside the heavier AST-N main battle mechs and AST-C heavy assault walkers, as a fast scout and infantry fighting vehicle. In the Civil Pacification and Sunikagrad's Red Guard, it is used for patrol duty.
The civilian variation bears something of a misnomer, as the walker is piloted by a single crewmember with additional space for an extra passenger and has very limited autonomous capability. However, the military variant is fully unmanned - although some tankers often modify police models to carry the heavier weaponry of the military model.
The loadouts used by the ART-51 vary dramatically depending on which model is being used. Police models are typically outfitted with a 6V24 Drakon Gatling laser on the side and a GSh-40 grenade machine gun, able to fire nonlethal rounds, such as flash and smoke, as well as lethal munitions. In addition, a foldable microwave active-denial system is oftentimes present on the top of a police walker for crowd suppression.
Military models have a much more vastly-expanded armament, the most common variation bearing either a 14.5-millimetre GShGm assault chaingun or (more recently) a TBP heavy plasma repeater. Rocket pods are also almost always present, though this can be replaced with a 9K42 Ballista guided missile system, a PSOP-2 plasma launcher, or even a 2A52 Burya 125-millimetre assault gun.
There also exists a light air defence variant of the military ART-51, the ZSU-30-4, armed with a battery of 30-millimetre autocannons on both sides of the cabin and a pair of surface-to-air missile pods on the top.
In order to preserve its great speed and agility, ART-51s rely more upon 'soft kill' countermeasures than on strong layers of armour or anti-projectile systems for protection - focusing on, rather than absorbing a strike, preventing the strike from occurring in the first instance. As a result, the walker possesses a full suite of jamming systems and adaptive camouflage in addition to various different types of flare and smoke, designed to beat infrared, RADAR and LIDAR targeting systems. Some specialised models are also equipped with active camouflage, allowing the walker to remain hidden in plain sight and thus get closer to enemy forces without being spotted and targeted.
In the event that these measures fail, the ART-51 can always rely upon its high speed and agility to escape a dangerous situation. Able to reach a top speed of 110 miles per hour even in dense vegetation and the urban sphere, it can easily outrun most other ground units and especially heavier vehicles (such as the NFE-operated M2 Greatsword main battle tank and M60 Clyde medium mechwalker) that may pose a serious threat to it. On the total flip side, it can also catch up to said units with great ease, making the ART-51 more than ideal for hounding fleeing enemies and hit-and-run skirmish tactics.
- The Red Guard variant of the ART-51 makes a brief appearance in A Blood Debt.