# Evaluation of the Acceleration Vibration Signal for Aggregates of the Horizontal Drilling Stand
## 5 Discussion and Future Work
A significant frequency is the value \(f=4000\) Hz, which is in several operating modes. However, when drilling rock is andesite in IX. operating mode, this frequency is not recognized. There is a significantly specific higher frequency band 6000-9000 Hz. Strategic is the three-dimensional representation of spectrograms, which allows us to study the dynamic time waveform of the vibrational signal in the time-frequency domain. The motor combined with another unit, without or with a drill bit, has a fundamental effect on intense vibrations if we compare the proposed operating modes without direct drilling of andesite rock. The greatest vibrations of the drilling equipment are caused by IX. operating mode, as the measured vibration signal includes higher frequencies, and andesite rock is disintegrated. The highest values of statistical characteristics in the time domain confirm the correctness of the result of vibration signal processing and the conclusion regarding the IX. operating mode. It is a view of signal processing and its presentation. However, if we look at applied research in terms of technical diagnostics of machines and equipment, it is complex technological machinery and a complex process of disintegration with many stochastic and non-linear elements. When looking at the measured and processed vibration signals in more detail, it can be stated that the machine vibrations are closely related to the dynamic stress of the machine and the technical condition of individual shaft parts, spindles, unbalances of rotating parts, backlash in sliding sliders, wear of the drill bit, material fatigue. The vibrations of the rig are driven by both rotating and rectilinear moving parts, including the movement of the flushing fluid. Practical experience confirms that the amplitude spectrum is used to detect the imbalance of the machine's rotating parts. For example, the headstock's misalignment with the drill bit is related to possible excessive wear. The low-frequency range corresponds to the speed range of the headstock with the drill bit. The frequency spectrum is fundamentally non-harmonic, corresponding to the speed of the component. Other possible faults of the drilling equipment are the mechanical play of individual parts, damaged drive V-belts, defects on sliding sliders, and electrical or magnetic faults on electrical units. The mid-frequency range corresponds to the frequency range of faults on electric motors. Therefore, spectral analysis of the vibration signal makes it possible to detect defects on the drilling stand such as wear of the contact surfaces of machine parts, ripping the diamond from the drill bit, and bending of the headstock with the drill bit, loosening of the drill bit. The area of high and very high frequencies is characterized by surface fatigue of the diamond element material, chipping of the surface layer material, abrasiveness with an increase in play, and grooving on the sliders. All these defects cause strong vibrations in the drilling equipment, which reduces the efficiency of the drilling process. Therefore, the primary goal of applied research and experimental laboratory measurements is vibration signal processing, identification of dominant frequencies, and fault localization. This will make it possible to innovate, reconstruct or replace faulty parts of the horizontal drilling stand. Early machine fault diagnosis allows for early repair and replacement of damaged parts, thus preventing an accident or damage to the entire machine. The following applied research will deal with the exact localization of defects on the drilling stand. Other methods for vibrational signal processing are also expected to be used, namely digital filtering, cepstral analysis, and wavelet transform. The research will also focus on developing new efficient methods for processing measured signals.