Fast two-stage filter algorithm applied to high precision digital weighing sensor

Abstract

The invention discloses a fast two-stage filter algorithm applied to a high precision digital weighing sensor, which comprises the following steps of: (1) as required by system, selectively designing two filters and setting a stability threshold and a stability condition; (2) opening a first-stage filter for basic data smoothing and for fast tracking for data variation; (3) opening a second-stage digital filter for further smoothing data when data output of the first-stage filter meets the stability condition; (4) closing the second-stage filter when data output of the first-stage filter does not meet the stability condition in the weight increasing or weight decreasing process of the system; and (5) repeating the steps (3) to (4) until the measurement comes to an end. The fast two-stage filter algorithm of the invention realizes seamless dynamic cascade of the filters at two stages by the method of setting the stability threshold and the stability condition, and compared with the traditional two-stage digital filter cascading algorithm, shortens the time for the reestablishment of the filters in the weight increasing or weight decreasing process of the system.

Description

technical field [0001] The invention relates to a filtering algorithm for a digital weighing sensor, belonging to the technical field of digital weighing. Background technique [0002] A load cell is a device that converts a mass signal into a measurable electrical signal output. It is a force sensor used on a weighing instrument. It can convert the gravity acting on the measured object into a measurable output in a certain proportion. Signal. [0003] Most of the traditional load cells use the traditional digital display instrument as the weighing display. The basic principle is to stimulate and receive the analog electrical signal from the strain bridge, perform amplification, analog-to-digital conversion, and finally output the digital value. Because the analog sensor transmits an analog signal, it is extremely susceptible to various noise interference, and the signal transmission line should be as short as possible, which makes the instrument installed as close as possi...

AI Technical Summary

Problems solved by technology

Its disadvantages are: it is not suitable for real-time application systems with high measurement speed requirements; and it has high requirements for the space complexity of the system

Its disadvantages are: low sensitivity, poor ability to suppress occasional pulse interference, it is not easy to eliminate the sampling value deviation caused by pulse interference, and it is not suitable for occasions with serious pulse interference; and the space complexity requirements of the system higher

The disadvantage is: it is not suitable for rapidly changing parameters; if the sampled value happens to be a disturbance value when the counter overflows, the disturbance value will be imported into the system as a valid input

However, in actual engineering practice, the two are often contradictory

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