A manipulator is a robotic device that moves and positions objects. It is the arm and the hand together, the part of the robot that does the work. Industrial manipulators weld, paint, pick, and place. Research manipulators handle fragile objects, assemble intricate parts, and explore underwater.

The word comes from the Latin manus, hand. A manipulator extends human reach and strength. It can work in environments too dangerous or too small for people: inside a nuclear reactor, on the ocean floor, or in a sterile surgical field. The design varies widely. A gantry manipulator moves on overhead rails. A mobile manipulator combines an arm with a wheeled base.

Manipulator components

• Base: mounts the manipulator to a surface or vehicle.
• Links: rigid segments between joints.
• Joints: revolute or prismatic axes of motion.
• End effector: the tool or gripper at the tip.
• Actuators and sensors: motors, encoders, force sensors.

A manipulator's capability depends on its reach, payload, speed, and precision. A large industrial manipulator might lift 500 kilograms but move slowly. A surgical manipulator might lift a few grams but move with micron precision. The control system coordinates the joints to produce smooth motion. Inverse kinematics converts a desired hand position into joint angles. Force control lets the manipulator push or pull with a specific force. The manipulator is the most visible part of most robots. It is the part that touches the world.