Event Driven Control for Robot Networked Control System with Disturbance

An event driven control method was designed for the disturbed robot networked control system, which combined the disturbance observer and event-triggered mechanism. The disturbance was compensated and the random time delay in the network was considered as well. Event driven can greatly reduce the network congestion and the computing burden of the controller, saving the communication channel bandwidth. When the controller determined whether the output error of the controlled robot met the preset event or not, it received the disturbance observation value from the disturbance observer at the same time. When the system output error did not meet the preset event, the controller used the system output error and disturbance observation value to calculate a new control input to replace the original control input signal; otherwise, the controller maintained the previous control input. The stability and convergence of the robot networked control system were proved. Finally, simulations were conducted on the network control system of a two-joint robot. The results show that the proposed method can observe the external disturbance, and hence, the controlled robot has good position tracking performance under the influence of disturbance and random network delay.