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.