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The difficulty of the signal processing is not the acquisition of the signals, but how to get the reasonble interpretations from the signals. Since the 1960s, Wavelet Transform, Fast Fourier method and other theoryies have done some works by some innovative processing methods to achieve a breakthrough. But for their limitions, these methods can not achieve a complete separation if the there are two or more signals in one time domain or frequency domain. In this article, a new engineering signal processing method-pattern filter method has is introduced, by which the signal extraction, sepration and noise reduction can be achieved successfully. Experiments show that this method can not only make a reasonable separation of the various vibration signals, but also give the typical signal extractions and model building ways.

A large amount of drilling pump vibration signals are acquired and decomposed optimally into time-frequency atoms by the Pattern Filter Method. All of these time-frequency atoms are falling into the multidimensional statistical cube which is formed by the time-frequency atomic parameter (α,f,φ,A) space with certain interval length. The atoms in every cube are counted and the results are stored in a database. When keeping any two parameters in a certain range, the quantitative distribution contour maps in the plane of other two parameters are demonstrated by the Graf software tool, then all sub-space results were aggregated to construct the macro-views of the BOU quantity distribution in the four-dimensional space ,meanwhile the quantitative distribution of these atoms are investigated, the distribution characteristics for various vibration signals of drilling pump are obtained and all atoms are classified according to their clustering state in this parametric space. Furthermore, every special signal corresponding to the parametric feature clustering of atoms in this multidimensional space have been identified. The desired results have been achieved in signal identification and drilling pump fault diagnosis by use of these consequences.

Because of magnetorheological (MR) dampers’ mechanical simplicity, high dynamic range, low power requirements, large force capacity and robustness, they are the most promising devices for structural vibration control. But this paper uses MR dampers’ damp characteristics to complete a function of short time delay, and the damper’s volume is smaller than the other dampers that have been applied for commercial uses. This paper discusses two types of structures for time delay, gap structure time delay device and holes structure time delay device. In order to estimate the two kinds of devices’ delay time, mathematical modeling and experimental testing are built in this paper. From the test results, we know that holes structure does not always implement theoretical delay time, but the gap structure can complete the time delay function satisfactory. For judging whether the time delay device can work normally under different circumstance, the time delay device with gap structure is tested in a change temperature field from -40 °C to 55 °C.