Overview
ISO 7626-1:2011 - part of the ISO 7626 series on mechanical vibration and shock - defines the basic terms and the transducer specifications needed to determine the suitability of impedance heads, force transducers and motion response transducers for measuring mechanical mobility. It gives guidelines for selection, calibration and evaluation of transducers and instruments used in driving‑point and transfer mobility, accelerance and dynamic compliance measurements. (Measurements of blocked impedance are explicitly not covered in this part; measurement procedures are in subsequent parts of ISO 7626.)
Key topics and technical requirements
- Terms, definitions and symbols: Harmonised vocabulary for mobility, accelerance, dynamic compliance and related frequency‑response functions (aligned with ISO 2041).
- Fundamentals and relationships: Basic frequency‑response function concepts and boundary condition definitions for driving‑point and transfer mobility.
- Transducer requirements:
- Motion measurement transducers (accelerometers, velocity or displacement transducers): general performance and environmental limits.
- Force transducers and impedance heads: physical mounting, end mass/effective mass considerations, and attachment characteristics.
- Calibration procedures:
- Operational calibrations and basic/supplementary transducer calibrations to verify suitability for mobility testing.
- Specific guidance for piezoelectric transducers: sensitivity, frequency response, transverse sensitivity, mass, dimensions, electrical impedance and polarity.
- Supplementary tests: linearity, effective end mass, compliance of impedance-head attachments, and environmental/secondary effect checks.
- Presentation of data: recommended plotting methods (logarithmic and alternatives) and reporting practices.
- Informative annexes: relationships between mechanical impedance/mobility and modal analysis, treatment of mobility as an FRF, and methods to determine impedance‑head attachment compliance and damping.
Practical applications and who uses this standard
ISO 7626-1:2011 is used to:
- Establish calibration and acceptance criteria for transducers used in mobility testing.
- Ensure traceable, repeatable mobility and accelerance measurements in laboratory and field testing.
- Support modal analysis, structural dynamics testing and vibration troubleshooting in product development and qualification.
Typical users:
- Vibration and acoustic engineers
- Test and calibration laboratories (metrology labs)
- Research institutions and universities working on structural dynamics
- Automotive, aerospace and mechanical OEM test teams
- Sensor and transducer manufacturers
Related standards (normative references)
- ISO 2041 - Vibration vocabulary
- ISO 16063 series - Calibration methods for vibration and shock transducers
- ISO 5347 - Methods for calibration of vibration pick‑ups
- IEC 60263 - Scales and sizes for plotting frequency characteristics
Keywords: ISO 7626-1:2011, mechanical mobility, impedance head, force transducer, motion response transducer, calibration, piezoelectric transducer, mobility measurements, mechanical vibration and shock.