In this paper the recent developments in the uncertainty evaluation are outlined, by describing the activity of the Joint Committee for Guides in Metrology- Working Group 1 on the Expression of Uncertainty in Measurement, and the documents that this WG is preparing on uncertainty.

In these paper, innovative developments in sine approximation and time interval analysis methods (SAM and TIA) for primary vibration calibration by heterodyne interferometry are described in detail. The frequency demodulation of novel TIA is based on estimation of time intervals between neighbouring peaks and valleys instead of traditional positive or negative zero-crossings of Laser Doppler Interferometer (LDI) signal, while the simplified SAM uses digital reference signal to generate quadrature signals and perform phase demodulation and differentiation to restore time history of velocity. Because of simplified algorithm and low requirements on hardware, these developments lead to a successful integration of SAM and TIA, both efficient and cost effective, for accurate result and reliable comparison in a single measurement, and to a novel implementation of national medium frequency vibration standard (10 Hz to 10 kHz) in National Institute of Metrology (NIM), China. The validity and accuracy of the novel methods is proved by simulation and will be further verified by a bilateral comparison underway.

Shock calibration is a major concern for a variety of mechanical applications. Examples of affected measurands are acceleration, force or torque. However, only for acceleration a written standard is available. This text discusses the problems which need to be addressed in order to disseminate the respective units for shock applications or to improve the current standard for acceleration and proposes a promising approach to solve them.

LNE has taken over the function of accelerometry reference laboratory following the decision of the CEACESTA to give up this activity. This article presents the principal stages in the transfer of the reference for medium and high frequency vibrations.

Primary angular acceleration calibration standard is developed by CIMM to generate standard rotational angle, angular velocity and angular acceleration, which are traceable to the International System of Units (SI). It can be used to calibrate angular transducers, i.e. angular accelerometer, angular velocity transducer, and rotational angle transducer to obtain amplitude sensitivity and phase shift by sinusoidal vibration. This paper will introduce the mechanic system, control system and measurement system of the standard. Calibration results of angular transducer using the standard also introduced. It shows that the standard can be used in angular movement calibration in the frequency range from 0.1 Hz to 200 Hz with amplitude uncertainty better than 1% and phase uncertainty of 1 degree.