基于样条函数的高精度电子秤设计

High precision electronic scale based on spline function

摘要:

通过对已有的各种电子秤的分析,从硬件和软件两个方面,提出提高电子秤测量精度的方法。硬件上采用专门为高精度设计的24位A/D转换芯片HX711,该芯片具有分辨率高、线性度好、功耗低等优点,特别适合低频高精度的应用场合。软件上引入样条函数,用光滑的参数曲线段逼近折线多边形,实现对非线性称重关系特性曲线的拟合和自校准,达到减小误差的目的。最后通过实验证明了该方法的有效性。

Abstract:

Various electronic scale have been intensively analyzed at first, from two aspects of hardware and software, and then the design method of improving electronic scale’s measurement accuracy is proposed. A 24 bit A/D converter HX711 is adopted which is specially designed for high precision in hardware, the chip has the advantages of high resolution、good linearity and low power consumption, and so on, especially suitable for low frequency and high precision applications. The spline function is introduced to go to line polygon approximation with smooth curve in software, implementing the nonlinear approximation and the calibration of the weighing characteristic curve, achieved the purpose of reduce error. Finally, the effectiveness of the method is proved by the experiment.