DynamInspect | ISO 7626 Mechanical Impedance Analysis – Foil Bearing Stiffness & Damping Measurement | SADAP
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Measure What Simulations Can't Predict

Real-world stiffness, damping & loss factor per ISO 7626

DynamInspect – ISO 7626 Mechanical Impedance Analysis Software for Foil Bearings | SADAP GmbH

DynamInspect

Mechanical Characterization According to ISO 7626 – Developed for Foil Bearings, Suitable for All Viscoelastic Products

From Measurement to Decision – In One Workflow

DynamInspect was specifically developed for the characterization of foil bearings and is the ideal solution for anyone who needs to precisely determine mechanical properties. The software is equally suitable for products with viscoelastic properties – from elastomer bearings to damping elements to complex joints. You'll learn how stiff your product is, how well it dampens vibrations, and how these properties behave across different frequencies. Particularly valuable for foil bearings: The automatic blocking detection immediately warns you if the bump foil cannot oscillate freely – a critical quality indicator before the bearing is used in real operation. With three analysis methods, flexible compliance levels, and AI-powered quality assessment, you make informed decisions – whether in quality control, the laboratory, or development.

DynamInspect Software Dashboard - Foil Bearing Characterization

Guided 4-Phase Workflow

Signal Check → Data Preparation → Impedance Analysis → Stiffness Analysis. With feedback for measurement setup optimization in the first two phases.

Three Analysis Methods

Frequency-dependent for rotordynamic simulations, Band-averaged for QC decisions, Modal MDOF for R&D – choose the appropriate method.

Real-Time Compliance Check

Automatic ISO 7626 compliance check with error diagnosis and concrete improvement suggestions. Critical for foil bearings: η < 0.02 means blocking. The software automatically warns you about manufacturing problems with the bump foil.

Analysis Metrics

6 automatic diagrams per phase: Visualize signal quality, coherence, spectra, and ISO compliance at a glance.

AI Quality Assessment

ML algorithms automatically detect anomalies. Health score 0-100 for quick decisions – with special foil bearing mode.

Flexible Compliance Levels

STRICT for certification (γ² ≥ 0.95), STANDARD for industrial applications, RELAXED for preliminary tests – adaptable to your requirements.

Uncertainty Analysis

ISO 7626 §7 uncertainty calculation: u(|Z|)/|Z| = √((1-γ²)/(2·n·γ²)). Know exactly how reliable your results are.

Flexible Data Exports

Excel, CSV, MATLAB, JSON – export K(f), C(f), η(f) for rotordynamic simulations, FEM tools, or your QMS.

ISO 7626 Test Reports

Automatic PDF reports with compliance checklist, measurement uncertainty, and action recommendations – ready for customers or documentation.

Discover the features by clicking on the pulsing dots

How It Works

From measurement setup to test report – a seamless workflow

DynamInspect supports you in both phases of your impedance measurement: First in capturing standard-compliant measurement data at the test stand, then in evaluating and characterizing your products. The software analyzes your raw data in the first two phases (Signal Check and Data Preparation) and immediately provides feedback on whether your measurement setup needs optimization – before you waste time with invalid measurements. After successful data acquisition, DynamInspect performs the complete impedance and stiffness analysis, extracts K(f), C(f), and η(f), automatically detects blocking in foil bearings, and creates ISO 7626-compliant test reports.

DynamInspect – ISO 7626 Impedance Analysis for Foil Bearings and Viscoelastic Products Measurement System Shaker Impedance Head F(t) a(t) (Force + Accel.) Test Specimen Foil Bearing / Viscoelastic Product Accelerometer (or Displacement Sensor) a(t) / x(t) Response Measurement Excitation Types (ISO 7626): Sine Sweep Random Data Acquisition System (DAQ) INPUTS F(t) a(t) x(t) USB/LAN Time Domain: F(t), a(t), x(t) → Software Examples: Ono Sokki • Brüel & Kjær • NI PXI Siemens/LMS • HBK SCADAS Signal Flow: F Impedance Head → DAQ (Force) a Impedance Head → DAQ (Accel.) x Response Sensor → DAQ (Disp./Accel.) Raw Data F(t), a(t), x(t) (Time Domain) Setup Optimization Feedback from Phase 1 & 2: DynamInspect Software 1. Signal Check Coherence γ² SNR, Quality ↺ 2. Data Preparation Filtering Conditioning ↺ 3. Impedance Analysis Z(f), H1/H2/Hv ISO 7626 §7 4. Stiffness Analysis K(f), C(f), η(f) Blocking Check Output Formats: Frequency-Dependent K(f), C(f), η(f) Curves → Simulation, FEM Band-Averaged Pass/Fail per Band → Quality Control Modal MDOF Natural Freq., ζ, Q → R&D, Design AI Quality Assessment • Automatic Blocking Detection (η < 0.02) • Health Score 0-100 • Anomaly Detection ISO 7626 Compliance STRICT STANDARD RELAXED Supporting Analyses: Analysis Metrics Statistical Analysis Uncertainty (§7) Waterfall Analysis Export: Excel • CSV • MATLAB • JSON • PDF Report Results Main Results: K(f) – Dynamic Stiffness C(f) – Damping Coefficient η(f) – Loss Factor Foil Bearing Specific: Blocking Status η < 0.02 → CRITICAL AI Health Score (0-100) Additional Outputs: • ISO 7626 Compliance Status • Measurement Uncertainty u(|Z|)/|Z| • Modal Parameters (fn, ζ, Q) • Band-Averaged Values • Action Recommendations PDF Test Report Loss Factor Interpretation for Foil Bearings ✓ Healthy η = 0.05 – 0.50 Bump foil oscillates freely ! Warning η = 0.02 – 0.05 Limited damping capability ✗ Blocking (CRITICAL) η < 0.02 Bearing not ready for operation! Measurement Setup per ISO 7626: • Electromagnetic Shaker → Impedance Head (measures F(t) and a(t)) → Test Specimen → Accelerometer (or Displacement Sensor) • Sine, Sweep, or Random excitation in the range 5-2000 Hz • Data Acquisition System (DAQ) for time domain data: Ono Sokki, Brüel & Kjær, NI PXI, Siemens/LMS, HBK SCADAS • Sampling rate ≥ 10× maximum frequency of interest DynamInspect Workflow: 1. Signal Check: Coherence γ² ≥ 0.90, SNR ≥ 20 dB (rec. 30 dB) → Feedback for setup optimization 2. Data Preparation: Filtering with energy conservation monitoring 3. Impedance Analysis: Z(f) with H1/H2/Hv, Uncertainty per §7 4. Stiffness Analysis: K(f), C(f), η(f) + Blocking Detection © SADAP GmbH – Braunschweig | www.sadap.de
Measurement Setup Feedback Phase 1 & 2 provide immediate feedback for optimizing your test stand
Data Acquisition + Evaluation One system for both tasks – standard-compliant measurement and characterization
ISO 7626 Compliance Automatic verification and documented evidence for your customers

Three Analysis Methods for Every Application

DynamInspect offers three specialized output formats that you can select depending on your application. Internally, the software uses multiple robust extraction algorithms (SDOF Curve Fit, Direct Extraction, Polynomial Fit) to deliver reliable results. Whether you need frequency-dependent data for your rotordynamic simulation, quick pass/fail decisions in quality control, or want to characterize individual structural modes for product development – you always get the appropriate results. Automatic blocking detection for foil bearings is integrated into all methods.

  • Frequency-Dependent Analysis: Provides continuous K(f), C(f), and η(f) curves across the entire frequency range. Ideal for comparison with FEM models and rotordynamic simulations. The frequency-dependent data can be exported directly to simulation software.
  • Band-Averaged Analysis: Calculates averaged values for defined frequency bands – perfect for quality control. You get clear pass/fail decisions and can quickly compare products within a batch. Typical bands: Start-up (100-200 Hz), Operation (300-500 Hz), Run-up (600-900 Hz).
  • Modal MDOF Analysis: Identifies individual structural modes with their natural frequency, modal stiffness, damping, and quality factor. Optimal for R&D and design to understand dynamic behavior in detail.
  • Automatic Blocking Detection: For foil bearings, DynamInspect automatically detects when the loss factor falls below 0.02 – a critical indication that the bump foil cannot oscillate freely. This feature prevents defective bearings from entering operation.
  • Flexible Compliance Levels: Choose between STRICT (for certification measurements), STANDARD (for industrial applications), or RELAXED (for screening tests). Each level adjusts the requirements for coherence, SNR, and uncertainty accordingly.
  • Universally Applicable: Although specifically optimized for foil bearings, DynamInspect is excellently suited for all products with viscoelastic properties – elastomer bearings, damping elements, joints, or complex structures.

Signal Check: Measurement Quality Validation According to ISO 7626 Phase 1

Spectral Analysis

Spectral Quality Assessment

Before analysis begins, DynamInspect checks the signal quality in the frequency domain. You immediately see whether disturbing influences are present and whether the prerequisites for reliable results are met.

  • Automatic detection of mains hum (50 Hz harmonics)
  • SNR analysis: ISO 7626 §5.3 requires ≥ 20 dB, recommended ≥ 30 dB
  • Stationarity check of raw data
Time Domain Analysis

Time Signal Validation

Force and displacement signals are displayed directly overlaid. Irregularities, outliers, or synchronization problems become immediately visible.

  • Clear display of both channels
  • Automatic outlier detection
  • Time synchronization check (Lag < 0.5 ms)
Coherence Preview

Coherence Preview

Coherence γ²(f) indicates how well force and displacement are related. ISO 7626 requires γ² ≥ 0.90, DynamInspect recommends γ² ≥ 0.95 for optimal results.

  • Traffic light system for quick assessment
  • Frequency ranges with problems marked
  • Dropout percentage calculated (Target: < 10%)
ISO Compliance Check

ISO 7626 Compliance Dashboard

All requirements are automatically checked against the selected compliance level – STRICT, STANDARD, or RELAXED. You see at a glance whether your measurement meets the standard.

  • Complete standard compliance check
  • Clear Go/No-Go decision
  • Improvement suggestions for deviations

Data Preparation: Signal Conditioning Without Quality Loss Phase 2

Signal Filtering

Signal Filtering

If necessary, you can condition your measurement data before analysis. DynamInspect offers various filter options while monitoring that no important signal components are lost.

  • High-pass, low-pass, and band-pass filters
  • Automatic parameter suggestions
  • Preview of filter effect
Before-After Comparison

Before-After Comparison

See directly how signal conditioning affects your data. DynamInspect warns you if processing changes more than 10% of the signal energy.

  • Overlay of original and filtered
  • RMS change and energy conservation
  • Acceptance criterion: Energy ratio 0.5-1.5
Coherence Improvement

Coherence Monitoring

Has the conditioning improved measurement quality? DynamInspect compares coherence before and after processing and warns of degradation (Δγ² < -0.05).

  • Coherence comparison before/after filtering
  • Warning on degradation
  • Recommendation: Accept or reset
Energy Conservation

Ensuring Signal Integrity

DynamInspect monitors that no important signal components are lost during conditioning. You see exactly how much energy is preserved.

  • Energy conservation analysis
  • Spectral distortion check
  • Automatic quality assessment

Impedance Analysis: Z(f) with Multiple Estimators and Uncertainty According to ISO 7626 §7 Phase 3

Mechanical Impedance

Mechanical Impedance Z(f)

Impedance describes your product's complex resistance to dynamic excitation. DynamInspect calculates Z(f) with various estimators – H1 for shaker excitation, H2 for impact, Hv as geometric mean.

  • Estimator selection: H1, H2, Hv according to ISO 7626-3
  • Welch-based spectral estimation
  • Automatic window optimization (Hann, Flat-top)
Uncertainty Analysis

Uncertainty According to ISO 7626 §7

For every result, DynamInspect calculates the measurement uncertainty according to the core formula from ISO 7626 §7: u(|Z|)/|Z| = √((1-γ²)/(2·n·γ²)). This way you know exactly how reliable your values are.

  • Coherence-based uncertainty estimation
  • Dependent on number of averages n
  • Target: u(|Z|)/|Z| < 10%
Modal Analysis

Resonance Detection

DynamInspect automatically finds all resonance frequencies and characterizes each one with natural frequency, damping ratio, and quality factor – important parameters for rotordynamics.

  • Peak-picking and circle-fit methods
  • Damping ratio ζ and quality factor Q
  • Coherence at each resonance
3D Waterfall Diagram

3D Waterfall Visualization

The waterfall diagram shows the entire measurement at a glance. Temporal changes in impedance, frequency drift, and stability problems become immediately visible.

  • |H(f,t)| as 3D surface
  • Mode tracking over measurement time
  • Stationarity check: CV% < 20%

Stiffness Analysis: K(f), C(f), η(f) with Blocking Detection for Foil Bearings Phase 4

Stiffness Analysis

Dynamic Stiffness K(f)

Stiffness is extracted from the real part of the impedance: K = Re(Z). DynamInspect offers three methods: Frequency-dependent for full K(f) curves, Band-averaged for QC, Modal for individual modes.

  • Frequency-dependent analysis for simulations
  • Band-averaged for quality control
  • Typical foil bearing values: 10⁵ - 10⁷ N/m
Damping Coefficient

Damping Coefficient C(f)

The damping coefficient is calculated from the imaginary part: C = Im(Z)/ω. It describes how strongly your product absorbs vibration energy – crucial for stable rotor operation.

  • Frequency-dependent damping
  • Phase angle validation
  • Positive values required
Loss Factor and Blocking

Loss Factor η(f) & Blocking Detection

The loss factor η = Im(Z)/Re(Z) is the critical indicator for foil bearings. At η < 0.02, DynamInspect warns of blocking – the bump foil cannot oscillate freely, the bearing is not ready for operation.

  • Healthy: η = 0.05 – 0.50
  • Warning: η = 0.02 – 0.05
  • CRITICAL: η < 0.02 → Blocking!
Band-Averaged Analysis

Band-Averaged QC Analysis

For quality control, DynamInspect offers predefined frequency bands that cover typical operating conditions. You get clear pass/fail decisions for each band.

  • Start-up: 100-200 Hz
  • Operation: 300-500 Hz (turbocharger/fuel cell)
  • Run-up: 600-900 Hz (high-speed)
  • CV% < 30% for acceptable variation

AI Assessment: Automatic Anomaly Detection and Health Score AI Analysis

Anomaly Detection

Automatic Anomaly Detection

The ML module analyzes your results with Isolation Forest and One-Class SVM algorithms. It automatically detects blocking in foil bearings, stiffness instabilities, and unusual frequency dependencies.

  • Foil bearing mode: Blocking detection (η < 0.02)
  • General mode: For viscoelastic materials
  • Auto-detect: Automatic mode selection
Health Score

Health Score 0-100

An objective quality score summarizes all results: Healthy (≥85), Minor Issues (≥60), Review Required (≥30), Critical (<30). Ideal for quick pass/fail decisions.

  • Considers all anomalies weighted
  • Blocking: -40 points (CRITICAL)
  • Stiffness instability: -25 points
Pattern Recognition

System Characterization

The AI automatically characterizes your system based on phase behavior: Stiffness-dominated (|φ| < 45°), Damping-dominated, Mass-dominated, or Multi-Resonant.

  • Automatic method recommendation
  • Adapted analysis recommendations
  • Optimal frequency ranges suggested
Recommendations

Concrete Action Recommendations

Based on the analysis, you receive concrete recommendations. For blocking: Check preload, assembly tolerances, surface condition. For instability: Repeat measurement, adjust frequency range.

  • Foil bearing-specific recommendations
  • Manufacturing-relevant hints
  • Measurement optimization suggestions

Documentation and Export: ISO 7626-Compliant Reports Reports

Report Generation

One-Click Report Generation

With one click, you create a complete test report in PDF format. All results, diagrams, blocking status, and compliance assessment are automatically compiled.

  • Professional layout with company logo
  • Health score prominently displayed
  • Blocking warning highlighted
Data Export

Export for Simulation & QMS

All frequency-dependent results K(f), C(f), η(f) can be exported in various formats – for rotordynamic simulation, FEM comparison, or your quality management system.

  • MATLAB .mat for simulations
  • Excel for tables and evaluations
  • CSV/JSON for system integration
Summary

Clear Summary

The results summary shows all important key figures at a glance – ideal for quick decisions in manufacturing and presentations for customers.

  • All main results on one page
  • Clear pass/fail with justification
  • Band comparison for QC
Compliance Report

ISO 7626 Compliance Documentation

The report documents compliance with all ISO 7626 requirements at the selected compliance level – important for certifications and customer requirements.

  • Complete compliance checklist
  • Compliance level documented
  • Measurement uncertainty according to ISO 7626 §7

More Than Just Four Phases: In-Depth Quality Assurance

Four supplementary analysis tools accompany every step – for maximum measurement reliability

The 4-phase workflow delivers your results. But how reliable are these results? DynamInspect goes one step further: Four specialized analysis tools run parallel to each phase and continuously check the quality of your measurement. For foil bearings, this means: You not only detect blocking, but also understand how reliable this detection is. For other viscoelastic products, you know exactly what uncertainties your stiffness and damping values are subject to.

Analysis Metrics

Visual Quick Overview

After each phase completion, you automatically receive 6 clear diagrams. You see at a glance whether your signals are clean, whether coherence is correct, and where potential problems lie – without having to dive deep into numbers.

Foil Bearing Example: The loss factor diagram immediately shows whether η is in the green range or if blocking is suspected.

Statistical Analysis

Numbers That Build Confidence

If you want to know more precisely: The statistical analysis provides quantitative metrics such as coefficients of variation, distribution tests, and correlation analyses. Ideal for documentation and comparison of measurements within a batch.

Foil Bearing Example: The stationarity test confirms that your measurement was stable throughout the entire recording – important for reproducible QC results.

Uncertainty Analysis

ISO 7626-Compliant Measurement Uncertainty

Every measurement result is only as good as its uncertainty. DynamInspect automatically calculates measurement uncertainty according to ISO 7626 §7 – from signal synchronization to final stiffness extraction. This way you know exactly how much confidence you can place in your values.

Foil Bearing Example: At γ² = 0.95 and 50 averages, the relative uncertainty is only 2.3% – your stiffness values are highly reliable.

Waterfall Analysis

Making Time-Frequency Stability Visible

The 3D waterfall analysis shows how your measurement evolves over time. Are the properties stable? Is there drift or transient disturbances? Particularly important for longer measurements or when you need to verify the stability of your test conditions.

Foil Bearing Example: Coherence evolution confirms that γ² remained ≥ 0.9 throughout the entire measurement duration – your ISO 7626 compliance is temporally verified.
The Interplay: While the main workflow delivers your results, the four side analyses validate every step. This way you not only get K(f), C(f), and η(f) – you also get the certainty that these values are reliable. For critical applications like foil bearing QC, this is the difference between "measured" and "reliably measured".

Technical Datasheet

All specifications, system requirements, and feature overview at a glance.

Download PDF

What Sets DynamInspect Apart

For Foil Bearing QC

  • Automatic blocking detection (η < 0.02) before installation
  • Band-averaged analysis for quick pass/fail decisions
  • Comparison of bearings within a batch
  • Health score 0-100 for objective assessment
  • Predefined frequency bands for typical operating conditions
  • Complete documentation for audits and customers

For Development & Simulation

  • Frequency-dependent K(f), C(f), η(f) for rotordynamics
  • MATLAB export for direct simulation import
  • Modal MDOF analysis for structural modes
  • Multiple estimators: H1, H2, Hv according to ISO 7626-3
  • Uncertainty specifications according to ISO 7626 §7
  • Also suitable for viscoelastic materials

Flexible & Standard-Compliant

  • Three compliance levels: STRICT, STANDARD, RELAXED
  • Guided 4-phase workflow
  • AI-powered quality assessment
  • Automatic system characterization
  • One-click ISO 7626-compliant reports
  • Concrete improvement suggestions for problems

Prefer to Have It Measured?

DynamInspect gives you the tools to measure yourself. But sometimes it's more practical to leave the measurement to experts – whether for individual projects, for validation, or when special equipment is needed.

Discover our Impedance Analysis Services – we perform the measurements for you and deliver meaningful reports with blocking assessment and operational recommendations.

Get Started with DynamInspect Today

Transform your mechanical impedance analyses into an efficient, precise process with our 4-phase methodology according to ISO 7626. Achieve standard-compliant results and minimize risks without specialized knowledge. Whether in automotive, railway, or aerospace engineering: Secure superior product quality through deep, AI-assisted structural analysis. Request your customized DynamInspect solution today.