Effect of hybrid task scheduling algorithm on manufacturing accuracy in software-based CNC system

In order to reveal the relationship between scheduling algorithms and manufacturing accuracy, a model-based method of analyzing mismachining tolerance is presented. First, for embedded implementation, the parameters relating to sampling jitter and input-output jitter are analyzed in depth. Then, based on the error evaluation from this research, a software-based CNC simulation model is established. Finally, simulations are performed to illuminate the effect of the scheduling algorithm on manufacturing accuracy. The results show that the error value is up to 0.64% for two-level scheduling and the maximum error values are 0.37% and 0.34% for EDF and PS algorithms, respectively. The research method in this paper may be employed to verify scheduling algorithms, which is very helpful for embedded system design oriented to software-based CNC systems.