In industrial robotics terminology: A robot’s articulated “arm” assembly—responsible for positioning and orienting the tool—is called the ______.

Introduction / Context:
Robotics uses precise terms for each part of an automated system. Understanding names like “manipulator,” “end effector,” and “actuator” is essential for selecting hardware, reading datasheets, and troubleshooting performance. The question asks for the correct name of the robot’s arm assembly that moves and positions tools in space.

Given Data / Assumptions:

• The “arm” refers to the multi-joint mechanical structure from base to wrist.
• Common related terms are provided as options.
• We assume a standard industrial robot (e.g., 6-DOF articulated arm).

Concept / Approach:
The manipulator is the robot’s arm structure made up of links and joints. The manipulator provides the degrees of freedom required to place and orient the tool. The end effector (such as a gripper or welder) attaches to the wrist. Actuators (motors) drive joints, and servomechanisms are control loops that manage position/velocity/torque.

Step-by-Step Solution:
Identify what the “arm” physically represents: links + joints.Match this structure to the robotics term “manipulator.”Differentiate end effector (tool), actuator (drive), and servomechanism (control system).Select “manipulator.”

Verification / Alternative check:
Robot kinematics texts define forward/inverse kinematics on the manipulator; the end effector pose is the output. This confirms that the arm assembly is the manipulator, independent of the tool attached.

Why Other Options Are Wrong:
End effector: the tool, not the arm.

Actuator: a component (motor), not the assembly.

Servomechanism: control method, not the physical arm.

None of the above: incorrect because “manipulator” fits precisely.

Common Pitfalls:
Calling the entire arm “the gripper.” The gripper is just one type of end effector; the arm that positions it is the manipulator.

Final Answer:
manipulator