Fine-Grained Vibration Characteristic Analysis for Washing Machine's Dehydration Stage

The national standard GB/T 4288–2018 (household and similar electric washing machines) requires seven vibration sensors to be installed on the outer case of the washing machine to measure the vibration of dehydration stage with strict conditions. Currently, there is no such automatic vibration detection system for washing machine on the market which can meet the requirements of this national standard. Therefore, this paper proposes a fine-grained vibration characteristic analysis method for washing machines based on 3D accelerometer array (7 sensors of 21-channel). In this paper, a multi-channel vibration automatic acquisition system is designed, which is based on the general-purpose automatic test system platform and 3D accelerometer array. The system is calibrated based on the multi-angle gravity method and linear fitting. The acceleration is calculated by the FFT-IFFT method, and the velocity and displacement are calculated based on the time domain integration method. The fine-grained vibration characteristic method means that the vibration data including acceleration, velocity and displacement are decomposed into the positive and negative components for each channel of the detection system. In this paper, a drum washing machine is taken as examples to verify the proposed method, and the fine vibration characteristics of the washing machine were analyzed.