Experimental frequency response acquisition

WinFACT module FRED

For the frequency response data acquisition the WinFACT module FRED has been developed. It allows the experimental frequency response recording. For that purpose a Wobble generator is built up by using the WinFACT drivers which generates the different frequencies. Therefore a hardware is needed which at least has one analog output and, of course, one analog input.

The main features of FRED are:

  • integration of the WinFACT drivers
  • observance of the measuring range
  • quick and clear configuration
  • data processing by multithreading and threrefore a good real time performance
  • graphical presentation of the measurement as well as of all recorded time responses
  • saving of the measurements
  • adding and deleting of frequencies afterwards

Especially the adding and deleting of frequencies afterwards is a feature which can make user’s work a lot easier: e. g. in case the amplitude is within the range of the measurement error because the damping of the plant is very high for the current frequency only the amplitude of the sinus oscillation has to be increased or a smaller measurement range has to be used and then the measuring for that frequency can again be executed. The phase is ambiguous because of the periodicity of the sinus signal. Therefore necessary corrections of the phase curve are automatically carried out. By that it is always possible to get well defined responses of phase and amplitude.

Bode diagram of an oscillating PT2 element. In the range of the resonance frequency frequency points were added afterwards.

Presentation of a measured frequency response as a Nyquist diagram


WinFACT 2016-demo version, as at April 4th, 2017

Documentations and product information

WinFACT 2016-Product overview (German)