In the metallographic laboratory, pre grinding and polishing of metallographic specimens are essential procedures during the preparation process. Grinding suspension needs to be added during the polishing process. This dropper is designed to facilitate the automatic addition and titration of polishing solution. This machine is an automatic titrator for metallographic sample grinding and polishing solution controlled by a microcontroller. It is output by a precision peristaltic pump, displayed and controlled by a touch panel for input speed, and powered by a motor24VThe DC brushed motor has a long service life and can completely replace manual dripping to achieve the goal of timed and uniform output of grinding and polishing fluid. This machine can adapt to the output of various suspensions and can be used independently on various grinding and polishing equipment. It is easy to operate, has a simple appearance, and is safe to use. It is an ideal supporting equipment for metallographic sample preparation.