I. Introduction
Drilling process is a crucial industrial process in the exploration of resources and energy. However, the geological environment becomes complicated with the increase in drilling depth, and the downhole fault is usually inevitable [1]. The detection of drilling faults is primarily dependent on the manual monitoring and knowledge of drilling engineers. Yet the job of drilling engineers may be tiresome and laborious, and the subjective risk of human judgment can not be avoided. Therefore, research on fault detection is essential for the safety of the drilling process.