柔性压阻式脉搏传感器特性曲线拟合方法

Characteristic curve fitting method of flexible piezoresistive pulse sensor

针对脉搏检测和传感器的非线性问题,引入了一种基于柔性压阻式传感器的脉搏采集系统,提出了基于最小二乘法的拟合方案。分别用指数拟合和多项式拟合两种方式,建立了传感器测量压力和传感器阻值的数学模型,并对两种拟合方法进行详尽的分析。结果表明:基于最小二乘法的多项式拟合方案在高阶条件下具有拟合精度高的优点,但容易出现过拟现象。指数拟合方案具有稳定的单调性,误差在可接受范围,更适合于脉搏采集系统。

Aiming at the problem of non-linearity of sensor and pulse detection,a pulse acquisition system based on flexible piezoresistive sensor is introduced,and the fitting schemes based on least square method are proposed.The mathematical model for sensor measurement pressure and sensor resistance is established by using exponential fitting and polynomial fitting respectively,and the two fitting methods are analyzed in detail.The results show that the polynomial fitting scheme based on the least squares method has the advantage of high fitting precision under high-order conditions,but it is prone to overfitting.The exponential fitting scheme has stable monotonicity and the error is in an acceptable range,which is more suitable for the pulse acquisition system.