Many fashioned leather patches are characterized by seamless but visible edges, finished by means of time-consuming iterative processes involving edge grinding and subsequent dying. In the last years great efforts have been made by scientific and technical community to automate many leather manufacturing processes; therefore, the need to carry out manually the edge dying procedure represents a bottleneck for the entire leather patch finishing process.

As a consequence the development of an automated dyeing procedure is advisable. The main purpose of the present work is to describe a Machine Vision based system for automatically dying leather patches edges. Such a system comprises two main parts: a Machine Vision (MV) system devoted to leathers edge detection and a CNC painting pantograph (2 axis Cartesian robot) whose painting tool is moved according to the output of the MV apparatus. The developed system, tested on a prototype dyeing machine, proved to be effective in delivering high quality leather patches edge finishing.