Construction kit for low-cost vibration analysis systems based on low-cost acceleration sensors

Low-cost vibration analysis systems are of high interest to be integrated in low-cost and medium-cost machines and equipment of everyday life. This article presents a construction kit for building up such low-cost vibration analysis systems. The construction kit contains micromechanical acceleration sensors with measurement ranges ±1.7g up to ±70g and frequency ranges from 0…400Hz up to 0…10kHz. The sensors have to be supplemented with analog filters. Simple RC-filters or Bessel-filters are proposed for noise reduction, Tchebycheff-filters built up as Sallen-Key-filters are proposed for anti-aliasing. Data acquisition and also digital signal processing is done with standard microcontrollers, calculating simple rms values or performing a Fast-Fourier-Transformation. The construction kit shows ways to choose a microcontroller and also literature presenting detailed algorithms. The accuracy of the measurement systems is in the area of 1% for simple signal processing and up to 15% performing a FFT.