There are four main types of driving mechanisms used in robotic arms: hydraulic drive, pneumatic drive, electrical drive, and mechanical drive.

1. Hydraulic driven type

A hydraulic driven robotic arm typically consists of a hydraulic motor (various oil cylinders, oil motors), servo valves, oil pumps, oil tanks, and other driving systems, which are operated by the actuator of the driving robotic arm. Usually, it has a great lifting capacity (up to several hundred kilograms or more), characterized by compact structure, smooth movement, impact resistance, vibration resistance, and good explosion-proof performance. However, hydraulic components require high manufacturing accuracy and sealing performance, otherwise oil leakage will pollute the environment.

2. Pneumatic driven type

Its driving system usually consists of a cylinder, an air valve, an air tank, and an air compressor. Its characteristics are convenient air source, fast action, simple structure, low cost, and easy maintenance. But it is difficult to control the speed and the air pressure should not be too high, so the grabbing ability is low.

3. Electric drive is the most commonly used driving method for robotic arms. Its characteristics are convenient power supply, fast response, high driving force (joint type load-bearing capacity has reached 400kg), easy signal detection, transmission, and processing, and can adopt multiple flexible control schemes. The driving motor generally adopts stepper motor, and DC servo motor (AC) is the main driving method. Due to the high speed of the motor, reduction mechanisms such as harmonic drive, RV cycloidal pinwheel drive, gear drive, spiral drive, and multi rod mechanism are usually required. Some robotic arms have started to use high torque, low-speed motors without reduction mechanisms for direct drive (DD), which can simplify the mechanism and improve control accuracy.

4. Mechanical driven type

Mechanical drive is only used in situations where the action is fixed. Generally, cam linkage mechanisms are used to achieve the specified actions. Its characteristics are reliable movements, high working speed, low cost, but not easy to adjust. Others also adopt hybrid driving, namely liquid gas or electric liquid hybrid driving.