A multi-position method of viscous measurement for small volume samples with high viscous

Measurements of viscosity of small-volume samples are critical in analytical chemistry, hydrodynamics, and micro-electromechanical systems. It is hard for the previous methods to measure the liquid with viscosity large than 150 mPa $\cdot \text{s}$ . To enlarge the measurement range, a viscosity measurement method, in which the sample volume is less than $15~\mu \text{L}$ , was designed in this article. In the proposed method, the measured range is expanded to 750 mPa $\cdot \text{s}$ by the combination of flexible hinge and cantilever. In addition, to reduce the effects of surface tension, a multiposition method is adopted. The calibration results showed that the method performed well, and the uncertainty analysis indicated high accuracy. The effects of vessel width, density, and temperature on the results are also investigated. The relative uncertainty of viscosity was estimated to be 3% indicating the validity of this method.