Optimal Combination Method for Weights Loading of the Deadweight Force Standard Machine

The study of deadweight force standard machines (DWM) that operate over a wide range is at the leading edge and a hot spot in force metrology. Optimizing the combination method of the weight load has important theoretical significance for improving the stability and accuracy of DWMs. Firstly, the law of weight loading position on a pendulum relevant to the hanging system through dynamical theory and finite element methods was studied, likewise the minimum pendular degree caused by the loading on the upper end of the hanging system was determined. Then, a method for optimal combination of weights was presented and carried out using MATLAB software. A force transducer of 1000 kN was selected to test on a 2 MN DWM, and the results show that the method can effectively improve the repeatability and linearity. Finally, compared with two random combination methods, the repeatability deviation decreased by more than 50%, and the linear deviation by approximately 10%.