The driving device of industrial robots is the core component that determines their movement ability. It is the power mechanism that makes the robot move and is the heart of the robot. This article will introduce different types of industrial robot drive devices, how they convert electrical or fluid energy into mechanical energy to meet the command signals of the control system, and achieve various work tasks. The power devices of industrial robots are categorized into three types based on their power sources: hydraulic drive, pneumatic drive, and electric drive. These three basic types can also be combined into composite drive devices as needed.
▶ Hydraulic drive device
The hydraulic drive device utilizes the stored energy in the liquid to drive the movement of industrial robots. This system utilizes linear displacement or rotary pistons, as well as hydraulic servo systems. The hydraulic servo system adjusts the flow cross-section through servo valves to achieve flow rate regulation proportional to the control signal. The characteristics of hydraulic drive include high power output, high torque to inertia ratio, fast response, and suitability for environments with large loads and inertia. However, due to the need to convert electrical energy into hydraulic energy, its efficiency is relatively low, and liquid leakage may cause environmental pollution and generate high noise. Therefore, in robots with low to medium loads, electric drive systems are usually used.
In the field of heavy industry, such as automobile manufacturing and metal processing, hydraulic drive devices are widely used. For example, in the field of automobile manufacturing, hydraulic systems are widely used to control robotic arms, enabling them to accurately grasp and operate heavy vehicle components such as the body and engine. In addition, hydraulic drive devices are commonly used in large excavators and cranes in the construction industry to provide sufficient power to operate heavy equipment.
▶ Pneumatic drive device
Pneumatic drive devices use air pressure to drive the movement of industrial robots, usually consisting of pistons and control valves. Its characteristics include high speed, simple structure, easy maintenance, and low cost, making it suitable for robots with small and medium loads. However, implementing servo control is relatively difficult, so it is mostly used for program-controlled robots, such as loading and unloading and stamping applications.
Pneumatic drive devices have a wide range of applications in automation on assembly lines. For example, in electronic manufacturing, pneumatic-driven robots are commonly used to process and assemble tiny electronic components such as circuit boards and semiconductors. In addition, in the packaging industry, pneumatically driven robots are used for filling, sealing, and labeling products to improve production efficiency.
▶ Electric drive device
The electric drive device adopts different methods, including stepper motor drive, DC servo motor drive, and AC servo motor drive. In recent years, low-inertia, high-torque AC/DC servo motors and their servo drives have been widely used in various types of robots. Its characteristics include no need for energy conversion, easy use, low noise, and flexible control. Most electric motors require the installation of precision transmission mechanisms, but DC brushed motors cannot be used in environments that require explosion-proofing. In recent years, the development of direct drive motors has enabled robots to achieve fast and high-precision positioning and has therefore been widely used in assembly robots.
Electric drive devices are widely used in various industrial fields. In pharmaceutical manufacturing, electric driven robots are used to accurately dispense drug ingredients to manufacture drugs. In the food processing industry, electric drive robots are used for automated food packaging and sorting. In addition, in the aerospace field, electric drive devices are commonly used to control robot arms for assembling and maintaining aircraft components, ensuring highly accurate assembly and maintenance work.
There is no superiority or inferiority to any device, the one that is suitable is the best. There are various types of driving devices for industrial robots, and it is crucial to choose the appropriate driving method according to different needs and application scenarios. These three types of driving devices play a key role in different industrial applications, helping robots achieve various tasks and improve production efficiency and product quality. Choosing the appropriate driving method usually depends on specific application requirements and industrial environments.
Advantages and disadvantages of three power devices for industrial robots:
1. Hydraulic drive:
Advantages: Fast response, easy standardization of structure, high throttling efficiency, and large load capacity
Disadvantages: Hydraulic seals are prone to problems and pose a fire hazard under certain conditions
Application areas: commonly used in spray painting industrial robots and heavy-duty industrial robots
2. Pneumatic drive:
Advantages: Fast response, simple structure, easy standardization, low installation requirements, low cost
Disadvantage: There is a risk of explosion when the pressure exceeds 10 atmospheres
Application field: Mostly used in point control handling robots
3. Electric drive
Advantages: Simple structure, flexible control, high precision
Disadvantages: Poor explosion-proof performance of DC brushed motors
Application field: Used in various high-precision arc welding and assembly industrial robots