Industrial robots are robots used in the industrial sector. They are not humanoid robots, but rather mimic the body structure of humans, such as a section of an arm or a lower body. They do not have hands, a mouth, ears, a nose, or eyes that are indispensable to humans. They exist purely for completing industrial tasks.
However, as a robot, it also has systems similar to humans, such as control systems, drive systems, perception systems, and so on.
This article will talk about its driving system.
The driving system, in simple terms, is the force that makes the robot move. What supports industrial robots to move with such precision, from picking up, moving, putting down, to returning to their original position? What is the required force here?
The answer is the robot drive structure.
Composed of a motor and a reducer, the motor adopts an absolute servo motor, and the reducer has two types: RV reducer and harmonic reducer. The motor and reducer are generally connected using a reducer shaft or a wave generator.
1. Motor type
Using absolute value servo motors: The motors in the robot drive system are mainly absolute value servo motors, which have closed-loop control capabilities for position, speed, and torque, high accuracy, and no stepping problems.
Other motor types: Some scenarios also use AC servo motors, DC servo motors, or stepper motors, but servo motors have become mainstream due to their fast response and precise control.
2. Types and division of labor of reducers
The mainstream reducers are generally RV reducers and harmonic reducers.
RV reducer: With a complex structure, strong rigidity, and high output torque, it is suitable for heavy-duty parts such as the base, waist, and boom, especially common in joints with loads of over 20kg.
Harmonic reducer: lightweight and compact, with high precision, commonly used for small arms, wrists and other parts with light loads or requiring high-precision transmission.
Other reduction mechanisms include planetary gear reducers, cycloidal pinwheel reducers, etc., but RV and harmonic are still the mainstream choices for industrial robot joints.
3. Connection method between motor and reducer
Core connecting components:
Gearbox shaft: Directly connect the motor output shaft to the gearbox input gear to achieve power transmission.
Wave generator: specifically designed for harmonic reducers, transmitting power through elastic deformation.
These structures together form the power system of the robot, analogous to the 'cardiovascular system'. Provide working power for robots.