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This document designed a stabilized platform of 2-DOF spherical parallel mechanism with 1-DOF in series. DC servo motors are adopted as the driver of the mechanism. The system uses an inertial gyro sensor as the feedback of the angular position. Software and hardware of the platform were developed. The full closed-loops control structure based on Advantech IPC with NI multifunction data acquisition card(PCI-6230), including current loop, velocity loop and angular position loop, gets wide speed range and high precision for angular tracking. Control software was the Matlab with embedded real-time QuaRC. Experiment results meet the technical index and precision requirement, and illustrate the practicability and effectiveness of the scheme.

Acoustic Emission (AE) technique has been demonstrated to be a valuable method for monitoring damage evolution of energetic materials under mechanical or thermal loads. In practice, both mechanical and thermal, the loading condition is normally very different or changed in wide range. In order to correctly understand AE features and damage evolution, it is very necessary to investigate the dependence of AE features on loading conditions. As an example, AE tests on Polymer Bonded Explosive (PBX) JOB-9003 specimens at different compressive loading rates have been done, and the dependence of AE features on compressive loading rate is revealed and discussed.