Vehicle Rotational Speed Diagnostics for Faulty Vibration Detection

The rotational speed signal is segmented into multiple speed bands using bandpass filters, each targeting specific vibration frequency ranges. This segmentation allows evaluation of vibrations in different frequency domains independently, improving measurement precision while maintaining signal quality by focusing on relevant frequency components rather than processing the entire spectrum with derivatives.

The patent continuously calculates characteristic values by integrating filtered speed bands over extended time periods rather than relying on discrete instantaneous derivative calculations. This continuous integration approach maintains the ability to capture instantaneous vibration information while simultaneously providing temporal analysis capability across the entire measurement period, enabling both precise momentary measurement and long-term trend analysis.

Instead of using traditional Fourier transform that converts time-domain signals to frequency-domain (losing temporal information), the patent integrates filtered speed bands over time to create characteristic values that preserve both frequency and temporal dimensions. This approach evaluates vibrations in the time domain while maintaining frequency selectivity through bandpass filtering, thereby preserving disturbance duration information while achieving frequency-domain resolution through selective filtering and integration.

The patent uses a single integration operation that processes multiple filtered speed bands simultaneously to generate comprehensive vibration characteristic values. This multi-functional approach allows the same integration mechanism to evaluate vibrations across different frequency ranges (multiple speed bands) without requiring separate processing paths for each band, thereby achieving precise frequency isolation while minimizing additional device complexity.