A vision-based embedded control system for crystal reorientation and inspection

This paper proposes a vision-based embedded motion control system that is developed in our research group. The system is an integration of three subsystems including, an embedded positioning platform, a vision system for inspection and a crystal reorientation system. The system is used as a positioning platform and crystal reorientation system to automate the crystal reorientation process. This process is important in ensuring that the units are correctly oriented for production processes. The focus of this research is placed on how to develop the embedded positioning platform, the crystal reorientation system, and how to improve the system performances including positioning and reorientation accuracy in high speed operation and quality of inspection. A distributed control architecture has been developed using PIC18F4520 microcontrollers. Tests run on the complete system have shown that the system is capable of a minimum indexing time of 1.53 units per second and a reorientation time of 1.42 seconds.