Name:  Upper Arm Actuator
Type (Category):  Core (Actuator)
Reference:  TechManual (p. 32)

Description:
A ’Mech’s joints are generally referred to as its actuators. This includes more than just the hinges between bones. An actuator includes the joint itself, the associated myomer bundles and the motor control units.

The actual joint is typically a ball joint like your hip or a hinge like your elbow, and it is the simplest component of an actuator. The joints are sealed and are usually filled with dry lubricants like graphite.

The joints are moved by the myomers, just as your joints are moved by their associated muscles. Before I get to the myomers, however, I want to describe how the myomers and joints are controlled. Each joint has an associated Motor Control Unit (MCU, for short) that sends commands—in the form of electrical power—to the myomer bundles. The MCUs are local managers that organize thousands of myomer fibers in each myomer bundle, contracting them and monitoring feedback. These MCUs are in turn commanded by higher-order control systems that interpret the MechWarrior’s input for the benefit of these units.

Game Rules:
This critical hit destroys the muscle (actuator) in the foot. The controlling player must make a Piloting Skill Roll at the end of the phase in which the critical hit occurred, with a +1 modifier (in addition to any other standard modifiers); see Making Piloting/Driving Skill Rolls.

For each foot actuator damaged, reduce the ’Mech’s Walking MP by 1 and add a +1 modifier to any subsequent Piloting Skill Roll. (The player must refigure the Running MP as well; multiply the new Walking MP by 1.5, rounding up.) A Piloting Skill Roll is required whenever the ’Mech jumps; the roll is made at the end of the ’Mech’s movement. For each foot actuator critical, apply a +1 to-hit modifier to all kick attacks.

These effects are cumulative with other leg and foot actuator damage.

BattleMechsIndustrialMechs

Prototype Date:	~2300
Production Date:	2350
Extinction Date:	—
Recovery Date:	—

WEAPONS AND EQUIPMENT COMBAT AND CONSTRUCTION TABLE
RULES LEVEL PROGRESSION TABLE
MegaMek Output → Critical Slot:  Upper Arm Actuator
Record Sheet Output → Critical Slot:  Upper Arm Actuator

Prototype Date:	~2300
Production Date:	2350
Extinction Date:	—
Recovery Date:	—

WEAPONS AND EQUIPMENT COMBAT AND CONSTRUCTION TABLE
RULES LEVEL PROGRESSION TABLE
MegaMek Output → Critical Slot:  Upper Arm Actuator
Record Sheet Output → Critical Slot:  Upper Arm Actuator

Prototype Date:	~2300
Production Date:	2350
Extinction Date:	—
Recovery Date:	—

WEAPONS AND EQUIPMENT COMBAT AND CONSTRUCTION TABLE
RULES LEVEL PROGRESSION TABLE
MegaMek Output → Critical Slot:  Upper Arm Actuator
Record Sheet Output → Critical Slot:  Upper Arm Actuator

Prototype Date:	~2300
Production Date:	2350
Extinction Date:	—
Recovery Date:	—

WEAPONS AND EQUIPMENT COMBAT AND CONSTRUCTION TABLE
RULES LEVEL PROGRESSION TABLE
MegaMek Output → Critical Slot:  Upper Arm Actuator
Record Sheet Output → Critical Slot:  Upper Arm Actuator