Experimental Investigation of Motor Current Signal Signature for Developing an Operator Assistance System for a Food Processor

摘要

Perturbations in the drawn current due to the fluctuation in load on the blade during the processing of food in a food processor has been used to design an operator assistance system. A robust signal processing scheme has been proposed in order to analyze the extremely feeble current fluctuations in the motor controller circuit. An enveloping technique followed by a wavelet based denoising filter has been proposed for extracting useful information from the acquired current signal. Output of this scheme is fed into an intelligent decision making algorithm, which primarily is able to take two kinds of decisions, finally assists the user in making certain informed judgments. One of these decisions deals with the completion of the mixing or grinding operation whereas the other deals with cautioning the user about the presence of undesirable impurities in the substance being processed. Effectiveness of the developed method has been demonstrated, first on an appropriately formulated simulation, and then on the acquired signal from the experimental setup.