Man-machine interface refers to the field of human and machine contact or mutual influence on information exchange and function, or the interface said man-machine interface, information exchange, functional contact or mutual influence, refers to the hard contact and soft contact of human and machine, this interface not only includes the direct contact of points, lines and surfaces, but also includes the role of long-distance information transmission and control space.

Human-machine interface design should consider the following principles:
1, user-centered basic design principles

In the process of system design, designers should grasp the characteristics of users and discover the needs of users. In the whole development process of the system to constantly seek the user's opinion, to consult the user. The design decision of the system should be combined with the user's work and application environment, and the user's requirements for the system must be understood. The best way to do this is to involve real users in development, so that the developers can properly understand the needs and goals of the users, and the system will be more successful.

2, the order principle

That is, according to the order of processing events, the order of access and viewing (such as from the whole to a single, from large to small, from upper to lower, etc.) and the control process, the main interface of monitoring management and man-machine dialogue and its secondary interface are designed.

3. Function principle

That is, according to the specific functional requirements of the object application environment and occasion, the parallel processing requirements of the same interface of various subsystem control types and different management objects, and the simultaneous requirements of multiple dialogue interactions, etc., the human-computer interaction interface is designed to distinguish multi-level menus, hierarchical prompt information and multiple dialog bars simultaneously by function. Thus, it is easy for users to distinguish and master the use rules and characteristics of the interactive interface, and improve its friendliness and easy operation.

4. Consistency principle

Including consistent color, consistent operation area, consistent text. That is, on the one hand, the interface color, shape and font are consistent with national, international or industry general standards. On the other hand, the interface color, shape and font are self-contained, and the colors of different devices and their same design status should be consistent. The consistency of the interface detail design allows the operator to feel comfortable looking at the interface without distracting him. Consistency also reduces operational errors for new operators, or operators dealing with issues in emergency situations.

5. Frequency principle

That is, according to the dialogue interaction frequency of the managed object, the hierarchical order of the man-machine interface and the display position of the dialog window list are designed to improve the frequency of monitoring and access to the dialogue.

6. Importance principle

That is, according to the importance and overall level of the management object in the control system, the position and prominence of the primary and secondary menus and dialogue Windows of the man-machine interface are designed, which helps the managers to grasp the primary and secondary of the control system, implement the order of control decisions, and realize the optimal scheduling and management.

7. Object-oriented principles

That is, according to the identity of the operator and the nature of the work, design a suitable and friendly man-machine interface. According to its work needs, it is appropriate to display tips, guidance and help information in pop-up Windows, so as to improve the user's interaction level and efficiency.

Human-machine interface, whether it is oriented to the field controller or the upper monitoring management, the two are closely related, and the field equipment objects they monitor and manage are the same, so many field equipment parameters are shared and transmitted between them. The standardized design of human-machine interface should be the future development direction, because it does reflect the simple, simple and practical basic wood principle, and fully expresses the people-oriented design concept. Various industrial control configuration software and programming tools provide powerful support means for making exquisite human-computer interaction interface, and the larger and more complex the system, the more can reflect its superiority.