ISO/TS 23521:2021 PDF

Overview

ISO/TS 23521:2021 - Road vehicles - Calibration procedure for displacement devices - defines a repeatable, traceable procedure to calibrate 1D displacement transducers with nearly linear transfer functions, specifically tailored for sensors used in automotive crash tests. The method applies to sensors removed from dummies or test systems and is valid for both analogue and digital outputs. The specification focuses on point‑to‑point calibration against a traceable reference and provides guidance on data collection, processing and reporting of key performance metrics.

Key topics and requirements

• Calibration environment
  • Perform in a temperature‑controlled laboratory between 20 °C and 25 °C.
  • Measurement system and sensor must be connected and warmed up as in normal operation.
• Mechanical setup
  • Secure sensor to a linear calibration fixture; use fixation components that may differ from in‑service assembly.
  • Eliminate mechanical play (loose screws, interfaces) before calibration.
• Calibration range and starting point
  • Establish a zero displacement point (DS) similar to the application; if unknown, set DS