Model-free PID controller with gain scheduling for turning processes

The model-free PID control method with fuzzy neuron gain scheduling is proposed for turning processes in this paper. In order to enhance the control system stability and adaptability to the plants with nonlinearities and uncertainties, the model-free PID controller is designed to keep the cutting force to be constant by changing the controller gain on-line when a cutting tool cuts at various cutting depth or the spindle operates in different speeds. In this control system, the PID controller is used to control the turning process, the neuron is applied to tune the PID controller gain, and a fuzzy scheme is set up to change the neuron gain. With the two examples of different turning processes, the experiments of using the proposed control method are made. The simulation results show the good performance of the model-free PID controller.