Abstract This paper presents the development and metrological validation of an automated 2-axis mass transfer system designed for the high-precision calibration of standards ranging from 2 to 50 kg. The system features a novel three-position design that accommodates a reference and two test masses, enabling efficient simultaneous calibration. The mechanical structure was validated for rigidity and maximum deflection using Finite Element Analysis (FEA). The system utilizes PID controllers tuned for an overdamped response (> 1) to neutralize mechanical oscillations and ensure a stable transfer process. A high-quality prototype capable of handling up to 20 kg was constructed to experimentally verify the design concept and control system. The results signpost that the automated system achieved improvements in expanded uncertainty (U) at a 95\% confidence level at (k = 2), ranging from 2\% at 20 kg to 19\% at 2 kg, primarily by reducing Type A repeatability uncertainty. This enhanced precision is primarily attributed to minimizing the uncertainty from measurement repeatability. The study, therefore, validates the method’s superior precision and highlights air buoyancy uncertainty as the principal limiting factor for future system enhancements. The high-quality prototype was compared with another commercial product (CC50001S-L) using Eₙ values, and all measurements fall between 0. 006 and 0. 025. These results confirm that there is no significant statistical difference, thereby validating the prototype’s performance.
Sayed et al. (Thu,) studied this question.