Backstory
In the BattleTech universe, the first BattleMech ever developed was the Mackie MSK-6S, described as a 100-ton box with legs. It was developed in 2439 by the Terran Hegemony, first deployed in 2443, and produced throughout the rest of the Inner Sphere after its construction plans were stolen in 2455. Significant development and refinement of the technology followed through subsequent centuries. 'Mech advancement in the Inner Sphere crested during the reign of the Star League, but slowly degraded during the protracted conflicts of the Succession Wars. Much of the infrastructure and expertise necessary to produce the most advanced models was lost, with the result that, by the early 31st century, most Great Houses were fielding models that were centuries old.
Star League-era BattleMech technology was preserved during this period of decline by a military faction later known as the Clans. Absent from the Inner Sphere for centuries, they returned in 3049 fielding 'Mechs of considerable sophistication and power. The first confirmed sighting of a Clan 'Mech by an Inner Sphere observer was that of a Timber Wolf (called the Mad Cat by Inner Sphere observers) by the legendary Phelan Kell of the Kell Hounds mercenary unit.
The Clan invasion triggered a resurgence of BattleMech-related research and development, both in the Inner Sphere and among the Clans, leading to many new models being introduced during the 3050s and '60s.
After the collapse of the 2nd Star League in late 3067, most Battlemech manufactures were damaged or outright destroyed by the Word of Blake Jihad (Holy War). Smaller factories retooled and began manufacturing ancient designs dating back to the Age of War when Mackie was first introduced. The creation of hybrids from these ancient designs and new technologies again led to a slow progress in 'Mech development, despite the return to all-out war and the use of nuclear weaponry.[2]
However, the collapse of the hyperpulse generator network in the early 32nd century disrupted 'Mech advancement.
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Terminology and nomenclature
The term "'Mech" broadly applies to all mecha within the BattleTech universe. BattleMechs, those that are intended for combat or related operations, are the predominant variety, with the result that the term is frequently applied to all BattleTech mecha. Non-combat models do exist, however, and are generally referred to as WorkMechs or UtilityMechs. These models tend to be specialized to perform a particular task such as harvesting, lumbering, scavenging, repair, etc.
OmniMechs are a sub-class of BattleMech that mount weapons and equipment in modular "pods". The pods are easily swapped or changed, enabling engineers to customize an OmniMech's components for any given mission.
With few exceptions, every major model of BattleMech bears both a name and an identifying code. Codes generally use letters from the 'Mech's name, followed by an alphanumeric reference to the submodel or variant. For example, the base model of the 70-ton Warhammer is WHM-6R, with variants WHM-6X, WHM-7A, etc. A single letter is normally used to indicate common variants of an OmniMech.
Clan 'Mechs are sometimes known by two different names, one assigned by its Clan creators and one by Inner Sphere observers. An example is the 75-ton Clan Timber Wolf, known in the Inner Sphere as the Mad Cat. This practice generally ceased after the mid 3060s
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Configuration
BattleMechs range in height from 7 to 17 meters (23 to 56 feet) and mass from 20 to 100 tonnes (22 to 110 short tons) in five-ton intervals, with some capable of ground speeds in excess of 150 km/h (93 mph). Mechs have a torso that can rotate to either side independently from the legs, but few can do a complete 360 twist. Their power is drawn from fusion reactors and are best suited for ground combat, although they are also capable of limited performance underwater and in outer space.
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Bipedal
The majority of BattleMechs are bipedal and can be classed as either humanoid or reverse-joint ("chicken walker"). Humanoid-type BattleMechs are the most common and include the iconic Atlas and Summoner (Thor). Reverse-joint 'Mechs are slightly less common on the field of battle, being quicker but less stable than the humanoid-type, but include such famous models as the Supernova, Marauder, Catapult, Timber Wolf (Mad Cat) and the Dire Wolf (Daishi). There are a few, however, with digitigrade legs that have a raised ankle and stand on their toes, like the legs of a dog, cat, etc. Examples include the Thanatos and Nova Cat.
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Quadrupedal
Four-legged "quad" 'Mechs constitute a small segment of official designs, and while they lack the flexibility and speed of bipedal designs, they are considerably more stable and can mount heavier weaponry. Though often maligned, quads experienced a bit of a renaissance in the years after 3060 with several new models released. Notable quad designs include the 25-ton Tarantula, 55-ton Scorpion, and 70-ton Barghest.
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Land-Air 'Mech (LAM)
LAMs are an extremely uncommon form of 'Mech capable of transforming between BattleMech and aircraft configurations, an ability that conveys great speed and flexibility at the cost of power and protection. The design of these LAMs, as well as several other 'Mechs, were leased from mecha designs used in The Super Dimension Fortress Macross and other anime series (see variable fighters); resulting real-world legal conflicts ended their official existence within the franchise. The Wasp, Stinger and Phoenix Hawk are the only published LAMs, found in the unrevised edition of Technical Readout: 3025, along with the other "lost" or "unseen" BattleMechs such as the Marauder, Crusader, Warhammer and the non-LAM versions of the Stinger, Wasp, and Phoenix Hawk.
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BattleMech Construction
BattleMechs are initially made up of a series of internal structure "bones" which are connected together to form a skeleton of the 'Mech. An electroactive polymer called myomer, which contracts in the presence of an electric current, is then wrapped around these bones. This powerful myomer transmission system is what gives BattleMechs their speed and agility in even the roughest terrain.
The necessary electric current for the myomers is provided by a fusion reactor mounted in the torso. This artificial skeleton and musculature, combined with a powerful gyroscope provide stability for the BattleMech. The entire system is controlled by a pilot wearing a neurohelmet that effectively links the 'Mech's central computer to the pilot's sense of balance and nervous system. The neurohelmet also gives feedback by providing a kinesthetic sense of the mech's position for better judgement of balance. The movement of a 'Mech is controlled by a combination throttle, joysticks, and dual pedal system.
The sections of a 'Mechs body have non-optional equipment that come with the internal structure such as cockpit, life support, sensors, engine, gyro and actuator packages. Additionally any spaces left over after you account for structure (Endo-steel) and armor upgrades (Ferro-Fibrous) is available space for the installation of heat sinks, weapon systems and applicable ammunition.
In some 'Mech-based games there are a series of different size and capacity rated hardpoints for the attachment of critical systems such as life support and cooling equipment. In addition, weapons and armor plating are also attached to these points to give the 'Mech its offensive and defensive capability.
'Mechs can carry a variety of weapons, most of which generate heat upon firing. This can become a problem in intense or prolonged fighting, as an overheating 'Mech may shut down or, in extreme cases, explode. To mitigate this, the heat is transferred into massive heat sinks, which help facilitate cooling but do not eliminate the problem entirely. Water is an effective coolant, but it also impairs movement.