*5.1.1 Network control model*

The network control system is generally divided into two structures, direct control and indirect control. The main difference between them is the signal transmission mode. Both the direct control signal and the sensor signal are transmitted through the network, and there is no restriction on the transmission network. The network that transmits the two signal flows can be independent of each other. The remote end of the indirect control structure is an independent closed-loop control system. The actuator signal collected by the sensor is directly fed back to the control system at the remote end and no longer fed back to the main controller to reduce the impact of the network on signal transmission.
