Intelligent Detection of Artificial Lateral Line for Biomimetic Robotic Fish Based on EMD and SVM

In view of the problems that underwater acoustic perception and information interaction system are often disturbed by reverberation or multipath effects, and the optical sensing is easily affected by water turbidity, a novel intelligent detection method of underwater moving target based on artificial lateral line(ALL) is proposed to accurately detect target in complicated underwater interferences for a biomimetic robotic fish. Firstly, the original signals received by the ALL system are decomposed into different intrinsic mode functions(IMFs) via empirical mode decomposition(EMD) to separate target signal from interferences. Secondly, the characteristic frequency of the vibrating target representing different fish is obtained from the IMFs to detect the underwater moving target. Finally, the power spectrums of the IMFs are input into the support vector machines(SVMs) to recognize the azimuth of underwater moving target intelligently. Water tank tests with combination of the proposed method with ALL detection are conducted, and the results show that the proposed method has better detection performance than the traditional methods, such as fast Fourier transform(FFT) and neural network.