The classification of robotic arms from four aspects: usage range, motion coordinate form, driving mode, and arm force size are as follows:

1. Classified by usage scope:

(1) Specialized robotic arms generally only have fixed programs and no separate control systems. It belongs to a certain machine or production line used to automatically transport objects or operate a certain tool, such as the "blank loading and unloading robot arm", "curved automatic lathe robot arm", "oil pump camshaft automatic line robot arm", and so on. This type of robotic arm has a relatively simple structure and low cost, making it suitable for large-scale production with simple movements.

(2) Universal mechanical fingers have a variable program and individually driven control system, are not subordinate to any particular machine, and can automatically transfer objects or operate certain mechanical devices. Universal robotic arms can be divided into two types based on their positioning and control methods: simple type and servo type. The simple type is only point control, so it belongs to the program control type. The servo type can be point control or continuous trajectory control, generally belonging to the digital control type.

2. Classified by motion coordinate type:

(1) The Cartesian coordinate robotic arm can move in three directions along the Cartesian coordinate axes X, Y, and Z, that is, the arm can stretch back and forth (defined as movement along the X direction), move left and right (defined as movement along the Y direction), and move up and down (defined as movement along the Z direction);

(2) The cylindrical coordinate robotic arm can move along the X and Z directions of the Cartesian coordinate axis, and can also rotate around the Z axis (referred to as rotation around the Z axis), that is, the arm can stretch back and forth, lift up and down, and rotate left and right;

(3) The spherical coordinate mechanical arm can move along the X-axis of the Cartesian coordinate system, and can also rotate around the Y-axis and Z-axis. In other words, the arm can stretch back and forth (move along the X-axis), swing up and down (defined as swinging around the Y-axis), and rotate left and right (still defined as rotating around the Z-axis);

(4) The arm of a multi joint robotic arm can be divided into a small arm and a large arm. The connection between the forearm and the upper arm (elbow), as well as the connection between the upper arm and the body (shoulder), are all joint (hinge) connections, that is, the forearm can swing up and down around the elbow with the upper arm, the upper arm can swing multiple angles around the shoulder, and the arm can also rotate left and right.

3. Classified by driving mode:

(1) Hydraulic driven robotic arm is driven by pressure oil;

(2) Pneumatic driven robotic arm is driven by compressed air;

(3) Electric driven robotic arms are directly driven by electric motors;

(4) Mechanical drive manipulator is a driving method that transmits the power of the main engine to the manipulator through cam, connecting rod, gear, intermittent mechanism, etc.

4. Classified by arm strength of the robotic arm:

(1) The force of the micro robotic arm is less than 1kg;

(2) The force of a small robotic arm is 1-10 kg;

(3) The force of a medium-sized robotic arm is 10-30kg;

(4) The force of a large robotic arm is greater than 30kg.