1. Classified by scope of use
(1) A dedicated manipulator is a mechanical device attached to the main machine, equipped with a fixed (and sometimes adjustable) program but lacking an independent control system. It features limited motion, a single workpiece type, a simple structure, and reliable operation, making it well suited for high-volume automated production. It is widely used in the light industry and electronics sectors.
(2) A general-purpose manipulator is a type of robotic arm equipped with an independent control system, programmable motion sequences, and flexible, versatile movements. It features a large working envelope, high positioning accuracy, and strong versatility, making it well suited for medium- and small‑batch automated production where product varieties change frequently. Consequently, it is widely employed in flexible automated production lines.
2. Classified by drive type
(1) Mechanical‑drive manipulators are robotic arms whose actuators are driven by mechanical transmission mechanisms—such as cams, linkages, gears, and racks. Their primary characteristics include precise and reliable motion and high cycle rates; however, they tend to be relatively large in size and have fixed motion sequences. They are typically employed as loading or unloading devices in automated systems.
(2) Hydraulic‑driven manipulator: This type of manipulator uses hydraulic pressure to drive its actuators. It offers a large payload capacity, a compact and lightweight structure, smooth transmission, flexible motion, stepless speed regulation, and continuous trajectory control. However, oil leakage significantly affects its performance; therefore, it places stringent demands on sealing components and is not suitable for operation under high‑ or low‑temperature conditions.
(3) Pneumatic manipulators are robotic arms that use compressed air pressure to drive the motion of their actuators. Their main advantages include readily available power sources, rapid pneumatic actuation, simple construction, and low cost, enabling operation in high‑temperature, high‑speed, and dusty environments. However, due to the compressibility of air, their speed stability is relatively poor, and because of the low pressure of the air supply, they are best suited for light‑load applications.
(4) Electric‑drive manipulators are robotic arms in which the actuating mechanism is driven directly by specially designed electric motors, linear motors, or stepper motors. Since they eliminate the need for intermediate transmission mechanisms, their structure is simple; among them, linear‑motor‑driven manipulators offer high speeds and long strokes, while being easy to operate and maintain. Mechanical design is increasingly trending toward “mechatronics,” and the use of electric direct drive in robotic arms is expected to grow steadily.