If there is no feedback between the output and input of the system, that is, the output of the control system has no influence on the control of the system, such a system is called open loop. Contrary to closed-loop control system. In the control system, the process of returning the output to the input through appropriate detection equipment and comparing it with the input is feedback. The control input of the system is not affected by the output. In an open-loop control system, there is no feedback path from output to input. Therefore, the open-loop control system is also called no feedback control system. The open-loop control system consists of a controller and a controlled object. The controller usually has a power amplification function. Compared with the closed-loop control system, the open-loop control system is simpler and more economical. Open-loop control system is mainly used for enhanced system.
The difference between open loop and closed loop:
1, with or without feedback;
2. Whether it is applicable to the current control. Open-loop control is generally an instantaneous control activity, and closed-loop control will last for a certain time, so it can be judged that,
The first shot is closer to the second shot. It is also a kind of feedback, but it will not affect the first shot, so it is open-loop control.
For example:
Adjust the faucet with 1-first, have an expected flow in mind. After the faucet is turned on, observe the existing flow with eyes and compare it with the expected value, and constantly adjust it by hand to form feedback closed-loop control;
Riding-Similarly, the direction and speed of travel are constantly revised to form a closed-loop control.