Development of digital viscometer based on Arduino to determine the viscosity of liquid

摘要

A viscometer is an instrument used to measure the viscosity of industrial products in the form of liquid substances. There are three kinds of the viscometer that are often used to measure of liquid viscosity, one of them is a falling ball viscometer. In Physics Laboratory, a falling ball viscometer is used for physics experiment, but the equipment is still manual. Determination of liquid viscosity using falling ball viscometer manually is very susceptible to human error making it less accurate. To overcome this problem, this research has successfully developed a digital falling ball viscometer using an Arduino micro controller to measure the viscosity of the liquid. This digital viscometer consists of a measuring tube, photo diode sensor, laser (light-emitting), Arduino micro controller, stative, and iron ball. The liquid samples whose viscosities measured are placed in a measuring tube. At the body of the measuring tube mounted two pairs of photo diode- laser sensors separated by a certain distance. The first sensor pair detects the start time and the second sensor pair detects the final time of the falling ball in the liquid sample. The falling time of the iron ball when moving in the liquid sample is calculated by automatically and it displayed on the LCD. The system test shows that the digital viscometer is functioning well with a standard deviation is 0.036. Based on measurements using this equipment, the coefficient viscosity of cooking oil is 0.032 Pa.s and the engine oil is 0.024 Pa.s. It is hoped that the digital viscometer can help users in physics experiment with accurate measurement to reduce human error in measuring the viscosity of the liquid.