In the machine programming process, AR systems are mainly applied to verify and optimize machine tool paths: the integra- tion of these technologies within traditional Computer Numerical Control (CNC) simulation systems is a focal research topic. The po- tentiality of AR application in this manufacturing field is to de- velop innovative tools for path verification based on AR-assisted in situ simulation systems: thus, these simulation systems have been modified from software-centric (as traditionally ones) to more ef- fective based on machine tool-centric system ( Zhang, Ong, & Nee, 2010 ).