I am currently doing my master internship to get a degree in mechatronics. For an experiment I would like to conduct, I am interested in using electroadhesion. For those who don't know about it, the principle is easy. Get two electrodes (side to side or interlaced), put them on a flat surface and apply a high DC voltage across the electrodes. The forces are developed on a molecular level, so I won't go into details. The electrodes are usually well separated (by a gap) and embedded in a dielectric material (silicone or overlaid in tape for the cheapest versions). When I say high voltage, it is around 2-6kV DC, more might cause air ionization between the electrodes.
I know this process was used in old HP plotters to hold the sheet of paper while the tracing pen moves on the paper, and I remembered touching the surface of one and feeling some kind of buzzing in my fingers. In my experiment, there might be contact between humans and the electroadhesive surface, and I am concerned about safety. The HV DC-DC converters used usually provide several kV at less than 1mA of max output current (Emco produces the C50 that gives 5kV at 0.2mA). I know a DC current around 1mA can give a slight sensation.
The question is: Provided the electrodes are covered by dielectric, will there be this buzzing feeling when touching the surface? If yes, is there any danger? Provided there are holes or imperfections (due to time damage) in the dielectric, is there a danger, if the person touches both electrodes at the same time (with a finger crossing both electrodes for example)? If yes, what kind? Simply a shock similar to when you rub a balloon and get shocked, or something nastier?
Thanks a lot for your answers! Sebastien