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Monitoring integrity of operating structures has become a crucialneed in industrial applications while motivation for moresustainable materials pushes forward the development of naturalfibre composites (NFC). The complexity and variability of theirfailure behaviour and mechanical properties still limit theexploitation of their full potential. Acoustic Emission (AE) hasshown promising results to predict remaining service life ofstructures, allowing identification, localisation and assessment ofdamages in composite materials. Thus, embedment of AE sensors couldbe a reliable solution for real-time Structural Health Monitoring(SHM). This paper aims to quantify

Residual vibrations are a recurrent problem in MEMS actuators leading to a limitation of their dynamics and lifespan. This paper presents a voltage-controlled technique and its applicability to suppress residual vibrations in high voltage (about 100 V) electrostatic comb-drive actuators. The studied actuator is composed of a driving module and a clutch module devoted to the step by step driving of linear or circular gears. The proposed method is based on a command shaping technique well adapted to be integrated in an Application-Specific Integrated Circuit (ASIC), especially for nomadic applications. Firstly, an electrodynamic characterization is used to extract the key voltages of the optimized command signals. The key voltages correspond to the beginning and the end of the actual displacement. The command signals consist of two begin/end voltage jumps and a linear voltage rise/fall in an optimized time between the key voltages. Then, experimental validations investigated the influence of voltage fall time for a MEMS chip and the resulting dispersion for a set of 8 MEMS chips. The results show that residual vibrations are reduced by a factor higher than 20 in terms of the amplitude rate of bounces against back stop and the settling time of free oscillations. Finally, an analog circuit capable of building the optimized command signals is proposed and will be implemented in the next generation of the ASIC driving the electrostatic two-module actuator.