Research of Pure Tone Detection for Faulted On-Vehicle Loudspeakers Based on Image Fractal
Gui Ling Tan, Yu Ming Qi, Sanpeng Deng, De Hua Miao, Wen Hua Gao · Applied Mechanics and Materials · 2014
At present, the detection accuracy of monitoring method by human ears is not satisfying in the pure tone detection of on-vehicle loudspeakers. To solve this problem, a new method is proposed to convert vehicle loudspeakers response signals into a two-dimensional image signal via wavelet packet analysis, which can increase the time-frequency of malfunction information. Through image binaryzation and pretreatment image-edge detection, the resulting signal would be recognized with box-counting dimension acquired in the process of gaining time-frequency image through fractal dimension as malfunctioned indications. Experiments show a rate of fault recognition as high as 95% , which meet the requirements of online vehicle loudspeaker detection.