Comparison between Raspberry Pi and Arduino controller of gas bubble monitoring for a fermentation process

บทคัดย่อ

Two types of controller, Raspberry Pi3 B and Arduino mega 2560, were used in a gas bubble counter equipped with a photo sensor for indicating progress of a fermentation process. The optimum temperature and and switching on/off of the light conditions of the gas bubble counter were studied and the counting performance of the gas bubble counter controlled by these controllers at optimum conditions were compared. It was found that the optimum temperature was 20-25 o C with turning on the light. It was also found that at optimum conditions, the percentage error of this gas counting device increased with increase of the rate of carbon dioxide gas bubbles produced in the fermentation process. The maximum percentage error of Raspberry Pi3 B controller was 1.5%, while Arduino mega 2560 was 2.25% at bubble rate of 135 bubbles/ minute. In addition, the change of rate of number of carbon dioxide bubbles corresponded to the change that would happen in the fermentation process. Information of the number of gas bubbles counted by the gas bubble counter can also be used to indicate the trend of the amount of ethyl alcohol produced by the fermentation process, which corresponds to the progress of fermentation process and also to the yeast growth rate.