What are industrial robots ?
" An industrial robot is simply a device that executes commands."
An industrial robot is a multi-jointed or multi-degree-of-freedom manipulator , a mechanical device that works through a control system and its own power, and is widely used in industrial production. One industrial robot can replace the labor of several people, working according to pre-defined standard workflows, helping to reduce defect rates and increase unit output. Since its inception, the core structure of industrial robots has not changed significantly. The parts that are "visible" to the average person have remained almost unchanged, but the "invisible" parts have undergone tremendous changes. New materials, new control concepts, and new sensors have transformed modern industrial robots from simple machines into highly integrated devices similar to servers. Yes, it's like a server, with the connected computers acting as cameras, laser rangefinders, and similar devices. Industrial robots generally consist of a mechanical body and a controller . Industrial robots use many motors to perform actions; essentially, controlling an industrial robot involves controlling those motors to rotate forward, reverse, rotate faster, or rotate with greater force. I believe you understand this. Therefore, to control these motors to move as you intend, a PLC is needed as a control platform to write the program. Industrial robots do not work in isolation. A production line requires multiple industrial robots to work together. In addition, the production line also includes other movable parts, such as conveyor belts, AGVs, etc. How these roles cooperate with each other also requires the coordination of PLC.
What is a PLC?
" PLC can coordinate and control these devices"
A PLC ( Programmable Logic Controller ) is a digital electronic system widely used in modern industry. A PLC contains various human-machine interface units and communication units, controlling equipment production through digital or analog inputs and outputs. Its working principle can be divided into three stages: input sampling, program execution, and output refresh, followed by a repetitive (or cyclical) process of input sampling, execution, and output.
A PLC can be simply understood as a small computer capable of performing many tasks. However, using a PLC to control industrial robots presents challenges. Common PLC instructions cannot be implemented, and controlling industrial robots requires writing numerous function libraries, which is beyond the capabilities of ordinary electrical engineers . While a PLC can fulfill the technical requirements of industrial robots, industrial robots cannot achieve the comprehensive capabilities of a PLC. In other words, industrial robots are a branch of PLC, and further refinements are developed to create specialized development environments for robot automation. These environments save developers significant development time while also providing mandatory safety measures. Examples include FANUC's robot systems and its own PLC systems.
What is automation?
" Automation consists of multiple such devices and PLCs."
Automation is a general term for the measurement, manipulation, information processing, and process control of machinery or production processes without direct human intervention, achieving predetermined goals . Currently, " embedded systems ," widely used in German and international manufacturing, completely embed mechanical or electrical components within the controlled device; they are specialized computer systems designed for specific applications. The concept of automation is a dynamic evolution. In the past, people understood automation, or its functional goal, as replacing human operation with mechanical actions to automatically complete specific tasks. This essentially meant automation replacing human physical labor . Later, with the development of electronics and information technology, especially with the emergence and widespread application of computers, the concept of automation has expanded to include using machines (including computers) not only to replace human physical labor but also to replace or assist mental labor in automatically completing specific tasks. The broad connotation of automation includes at least the following: In terms of form, manufacturing automation has three aspects: replacing human physical labor, replacing or assisting human mental labor, and the coordination, management, control, and optimization of humans, machines, and the entire system within a manufacturing system. In terms of function, automation replacing human physical or mental labor is only one part of the functional goal system of automation. The functional goals of automation are multifaceted and have formed an organic system. In terms of scope, manufacturing automation involves not only specific production processes, but also all processes throughout the product lifecycle.
Summarize
After reading the introductions of the three, I wonder if you can discover any connection between them?
Indeed, the most important characteristic of industrial robots is their ability to work "according to a pre-set standard workflow," while PLC is a "digital computing and operating electronic system" that includes "multiple human-machine interfaces," and automation includes the two characteristics of "achieving expected goals" and "dedicated computer systems."
Therefore, during the production line changeover process, only the PLC program needs to be modified and the industrial robot needs to be fine-tuned to start a new round of production.
Therefore, learning PLCs allows for a deeper understanding of industrial robots and the overall working conditions of the workplace. PLCs are essential for engineers to flexibly utilize and control industrial automation. Otherwise, one can only perform simple start-up and stop operations based on pre-set configurations. Without some PLC knowledge, even basic maintenance skills may not be sufficient.
