1. Point To Point Control Mode
The point control system is actually a position servo system, and their basic structure and composition are basically the same, but the focus is different, and the complexity of control is also different. A point control system generally includes the final mechanical actuator, mechanical transmission mechanism, power element, controller, position measurement device, etc. The mechanical actuator is the action component that completes functional requirements, such as the robotic arm of a welding robot, the workbench of a CNC machining machine, etc. In a broad sense, actuators also include motion support components such as guide rails, which play a crucial role in positioning accuracy.
This control method only controls the position and posture of certain specified discrete points of the industrial robot terminal actuator in the workspace. In control, industrial robots are only required to move quickly and accurately between adjacent points, without requiring the trajectory of the target point to reach the target point. The positioning accuracy and the required time for motion are the two main technical indicators of this control method. This control method has the characteristics of simple implementation and low positioning accuracy. Therefore, it is commonly used for the loading and unloading, spot welding, and placement of components on circuit boards, only requiring the position and posture of the terminal actuator to be accurate at the target point. This method is relatively simple, but it is difficult to achieve a positioning accuracy of 2-3 μ m.
2. Continuous trajectory control method
This control method continuously controls the position and posture of the end effector of an industrial robot in the workspace, requiring it to strictly follow the predetermined trajectory and speed to move within a certain accuracy range, with controllable speed, smooth trajectory, and stable motion, in order to complete the operation task. Among them, trajectory accuracy and motion stability are the two most important indicators.
The joints of industrial robots move continuously and synchronously, and the end effectors of industrial robots can form continuous trajectories. The main technical indicators of this control method are the trajectory tracking accuracy and stability of the end effector of industrial robots, which are commonly used in arc welding, painting, hair removal, and detection robots.
3. Force control mode
When robots complete tasks related to the environment, such as grinding and assembly, simple position control can lead to significant position errors, causing damage to parts or robots. When robots move in this motion limited environment, they often need to combine ability control to be used, and they must use (torque) servo mode. The principle of this control method is basically the same as position servo control, except that the input and feedback are not position signals, but force (torque) signals, so the system must have a powerful torque sensor. Sometimes, adaptive control also utilizes sensing functions such as proximity and sliding.
4. Intelligent control methods
The intelligent control of robots is to acquire knowledge of the surrounding environment through sensors and make corresponding decisions based on their internal knowledge base. By adopting intelligent control technology, the robot has strong environmental adaptability and self-learning ability. The development of intelligent control technology relies on the rapid development of artificial intelligence, such as artificial neural networks, genetic algorithms, genetic algorithms, expert systems, etc. Perhaps this control method really has the taste of artificial intelligence landing for industrial robots, which is also the most difficult to control. In addition to algorithms, it also heavily relies on the accuracy of components.
Post time: Jul-05-2024
