Improvement of accuracy for continuous mass measurement in checkweighers with an adaptive notch filter

Abstract

With increased automation in the manufacturing industry, the demand for a quick and accurate mass measurement system is growing. Currently, the active belt conveyer is demanded by many enterprises. However, three mechanical noises, a peculiar frequency, a frequency of motor, a frequency of Belt pulley, are included in the observation signal from the active belt conveyer. Therefore, we have to remove those noises for the accuracy. In the current mass measurement system, the moving method is applied to remove those noises. However, it is inadequate only in the moving average method for more quick and accurate measurement. Therefore, we propose a frequency analysis method using the complex LMS algorithm. In this method, oscillation elements included in observation signals is converged every analysis frequency. Since time to converge depends on the constant value called the step size parameter, even in case of few obtained signals noises are removed and the accuracy seems to improve. In this study, the utility of the method is experimentally verified.