A Review of Research on Machine Vision-Based Dimensional Measurement Methods for Parts

With the continual advancement of industrialization and automation levels in the context of Intelligent Manufacturing 2025, machine vision-based part-size measuring technology has emerged as a research hotspot. First, this paper explains the history of machine vision technology's development, its fundamental ideas, and the state of its research both at home and abroad. Next, the challenges facing machine vision measurement accuracy today are identified, and a solution to increase measurement accuracy and efficiency through two factors-hardware system and software processing algorithm-is proposed. Second, the light source and lighting technique are examined in the context of the hardware system, with an emphasis on the analysis of the selection of the light source and the lighting technique appropriate for the measurement of part dimensions; Third, the sub-pixel edge detection technology is investigated and examined in the context of the software processing algorithm, and the most widely applied sub-pixel edge detection technology is summarized. Finally, the qualities and limits of part size measuring technology based on machine vision are outlined, and a roadmap for further research is suggested.