Real time assessment of hand-arm vibration system based on capacitive MEMS accelerometers

Vibrations are a well known potential cause of health diseases and therefore constitute a main concern for the safety of workers in a large number of activities. In order to prevent health hazards, national and international institutions have issued laws and directives which establish recommended limits to the workers' exposure to vibrations during operations. Consequently, if the amount of adsorbed vibration exceeds the allowable daily limits the worker has to stop his job. Recent wireless sensing and communicating technologies can effectively be employed for such purpose, allowing to develop monitoring customized devices at affordable cost which could be easily employed during the workers' activity. In such context, the present research proposes an innovative system aimed at estimating the hand-arm exposure to vibration according to the Standard EN ISO 5349-1:2004. In particular the proposed system is based on Micro Electro-Mechanical Systems (MEMS) technology and involves the design of a compact wearable unit to be attached to the waist of the operator and a fixed station for data storage and analysis. The paper reports the design of such a system and an experimental test performed on hand held shakers commonly employed for olive harvesting. The results highlight the opportunities offered by these emerging technologies in developing intelligent devices to be included in the worker's equipment which might significantly modify the current approach to safety management in the next future. © 2012 Elsevier B.V..