Here is an article straight from Jaxa: http://iss.jaxa.jp/en/kiboexp/news/170714_int_ball_en.html http://iss.jaxa.jp/en/kiboexp/news/170714_int_ball_en.html Th

Here is an article straight from Jaxa: http://iss.jaxa.jp/en/kiboexp/news/170714_int_ball_en.html http://iss.jaxa.jp/en/kiboexp/news/170714_int_ball_en.html They also don't say, but they link to this article: http://www.kenkai.jaxa.jp/eng/research/electrical/triaxial.html http://www.kenkai.jaxa.jp/eng/research/electrical/triaxial.h... which has a lot more technical detail. Unfortunately I don't have time to dig deeper, but hopefully it will help you search a bit better.