电容称重传感器特性曲线的拟合方法研究

摘要

Characteristic curve of Capacitance weighing transducer is the basis of weighing , calculation and nonlinear correction , and its accuracy directly affects the effect of weighing .According to the use of the traditional least square method to polynomial fitting of capacitance weighing transducer characteristics curve , apparent error appear in landmarks .Therefore , the three spline function interpolation to fitting capacitance weighing transducer characteristics curve is presented in the paper , and the fitting curve equation is established .Finally, an application example is given , and the results show that the fitting curve of Capacitance weighing transducer with the three spline function interpolation is smooth , and has little relative error in comparison with the original curve , and more accord with the actual characteristics of the transducer .So, the method has high practical value .%电容称重传感器的特性曲线是进行称重计算及非线性校正的基础，其精确性直接影响着称重的效果。针对采用传统的最小二乘法对电容称重传感器特性曲线进行多项式拟合时，在标定点出现明显误差的现象，提出采用三次样条函数插值对电容称重传感器的特性曲线进行拟合，建立了拟合曲线方程。最后给出了应用实例，结果表明通过三次样条函数插值所获得的电容称重传感器特性曲线光滑性好，误差较小，更符合传感器实际的特性，具有较高的实用价值。