Structural Dynamics Software

Type 8412 (Replaces Type 8729-C)  BK Connect Advanced Sine Measurements

Type 8412 (Replaces Type 8729-C) BK Connect Advanced Sine Measurements

BK Connect Advanced Sine Measurements is used for easy set-up, acquisition and validation of FRFs and related functions using stepped sine excitation. Stepped sine measurement is a technique, where sine excitation and corresponding measurements are made at fixed frequencies one at a time. Stepped sine measurements are often used as a complement to, or instead of, broadband random measurements, as it can provide more accurate results and allows for linearity studies.

This application emphasizes scalability and high productivity in the most time-consuming aspects of stepped sine measurements:

  • Setting up transducers, channel tables, excitation and analysis parameters
  • Fast acquisition of FRFs and related functions without compromising quality
  • Post-processing, displaying and reporting results


  • Acquiring leakage-free FRF measurements as input to very accurate modal analysis, for example, for ground vibration testing (GVT) of aircraft
  • Testing of large structures such as ships, trains and lorries by concentration of energy
  • Resonance surveys of critical modes
  • Forced response ODS analysis
  • Control and study of non-linearities of complex structures

BK Connect Advanced Sine Measurements is usually paired with BK Connect Modal Analysis Type 8420  and BK Connect Advanced Modal Analysis Type 8420-A for a streamlined modal measurement and analysis system using a common, intuitive and highly customizable user interface. Combining Advanced Sine Measurements with BK Connect Correlation Analysis Type 8421 adds test-FEA model correlation.


With BK Connect Advanced Sine Measurements you can perform stepped sine measurements with single- or multi-shaker excitation. For multi-shaker excitation, the calculation of FRFs and related functions requires more measurements. Different stepped sine series definitions are supported for the highest possible flexibility and time efficiency.

This application supports closed-loop control. To protect the test item and avoid too-high response levels during the measurements, alarm and abort levels can be specified. The levels are taken directly from the LAN-XI hardware to avoid any potential software delays.


Data acquisition hardware is displayed in an interactive graphic visualization that gives simple channel selection, transducer verification and a clear overview of any potential issues such as transducer overloads and cable breaks. For larger set-ups, channels can be listed and sorted according to status for quick resolution of issues. Specialists will appreciate the high level of flexibility in test setup and execution as well as the strong interface to finite element (FE) models for test planning and validation.


  • Geometry-guided  stepped sine measurements using BK Connect Modal Analysis Type 8420 or BK Connect Data Processing Type 8403
  • Application controlled closed-loop measurements with user-defined immediate alarm and abort levels
  • Optimal, Full MIMO, Manual or Specific stepped sine series definitions
  • Tracked data sampling for reduced measurement time
  • Generator panel with amplitude sliders for manual control
  • Force and Control Signal monitor displaying amplitude and phase values with tolerance bands
  • Result Matrix tool for easy display, comparison and reporting of results
  • SI and imperial measurement units, as well as acceleration in ‘g’


  • BK Connect Data Viewer Type 8400
  • BK Connect Hardware Setup 8401
  • BK Connect Geometry Type 8410