Investigation of the vibration assistance on the bark peeling tool to reduce the force required for cinnamon (Cinnamomum zeylanicum) peeling

Cinnamon (Cinnamomum zeylanicum) is the predominant spice among other export crops in Sri Lanka. The bark peeling process of cinnamon requires high skilled labour and the force required is subordinate only to the bark rubbing step. Since the traditional tools used for peeling are inefficient, a study was conducted to explore possibilities of using a vibration-assisted peeling knife to reduce the required force for cinnamon peeling and to enhance productivity. Three types of eccentric rotating mass motors (RF-555, R260 and MABUCHI RF-M50WA) were fixed to induce mechanical vibrations to the peeling knife. Vibration generated from the selected motors was changed by means of frequency and acceleration through the supply voltage, and respective values were recorded by an accelerometer. Selected cinnamon sticks (diameter 3.5 cm and length 10 cm) were tested by peeling out of 5 mm width bark strip from the stick at each frequency – acceleration rate values. As a control test, sticks with similar diameter and length were peeled without the vibration assistance. The motor RF555- ERM, offered the highest advantage for the peeling force reduction (73.22% - 78.6%) when compared to the control test. The results showed that the potential of using ERM in vibration-assisted tools to reduce the bark peeling forces of cinnamon sticks.