Overview
ISO 15261:2004/Amd 1:2016 is an amendment to the ISO 15261 vocabulary for vibration and shock generating systems. This amendment updates key terminology used to describe vibration test equipment (shakers) and, in particular, replaces subclause 3.12 with a clarified definition of the transverse motion ratio. The document is maintained by ISO/TC 108 (Mechanical vibration, shock and condition monitoring), Subcommittee SC 6.
Key topics
- Vocabulary for vibration and shock generating systems: standardized terms that ensure consistent communication across test labs, manufacturers and regulators.
- Transverse motion ratio (T): the amendment replaces the earlier text with a precise definition:
- T is the maximum ratio of a vibration quantity (acceleration, velocity or displacement) measured in a direction perpendicular to the operating axis of a vibration generator to the specified amplitude along the operating axis under sine excitation.
- The transverse component is calculated from two orthogonal axes in the plane perpendicular to the operating axis (root-sum-square of the two orthogonal transverse components).
- T is normally expressed as a percentage and is frequency-dependent.
- Scope of quantities: applies equally to acceleration, velocity and displacement measures used in vibration testing.
- Editorial and copyright details: the amendment follows ISO/IEC Directives and notes possible patent declarations.
Applications
- Shaker specification and acceptance testing: use the transverse motion ratio to evaluate off-axis motion of vibration generators and to set acceptance criteria when procuring shakers.
- Test setup and fixture design: engineers use T to assess fixture alignment, mounting quality, and to minimize unwanted transverse responses that can invalidate test results.
- Laboratory quality assurance: vibration test labs rely on standardized vocabulary to document test reports, ensure repeatability, and demonstrate conformance to client or regulatory requirements.
- Industry sectors: applicable in aerospace, automotive, defense, electronics, and any industry performing environmental vibration or shock testing.
Who should use this standard
- Vibration and shock test engineers
- Laboratory managers and QA personnel
- Shaker and instrument manufacturers
- Standards committees and certification bodies
- Procurement and technical specification authors
Related standards
- Other ISO/TC 108 mechanical vibration and shock publications and vocabulary documents (refer to ISO/TC 108 for related standards and guidance).
Keywords: vibration and shock generating systems, ISO 15261 amendment, transverse motion ratio, vibration testing, shaker performance, mechanical vibration vocabulary, sine excitation, frequency-dependent.
