Study on network architecture based on RTnet in CNC system

To solve the problem that a single processor cannot afford the computational load of the key algorithms in conventional CNC system, a network architecture based on RTnet is proposed in this paper. A resource-consumption and low coupling module in CNC was disjoint first from other modules. RTnet was used for communication between remote modules. Then, by means of Linux Real Time mechanism (LXRT), real-time performance of modules in user space was improved. After that, a prototype system was developed based on the above design idea. Furthermore, in order to compare the performance of the prototype system and conventional system, three experiments were carried out in aspects of periodic stability, local data transmission rate and network delay. The results show that the new scheme effectively reduces the processor burden, relieves resource tension, ensures periodic stability, increases local data processing speed and transmission rate, and decreases network delay. The prototype system realizes the balance between the computational capability of nodes and network communication load, and guarantees quality of service (QoS) in network and quality of performance (QoP) in control.