In order to control his bladder cancer, he used the Japanese concept of Ryodoraku, which is actually the same as the twelve meridian points on the skin, to measure reactions to electric current. Before becoming a physician, Voll was an electrical engineer. He designed an instrument on his own to measure electric light.
原來他得了膀胱癌，為了控制病情，他擷取日本人由經絡之說發展出來的「良導絡」理論﹘ ﹘皮膚上的穴道，對電流有反應，可用儀器測量；加上在做醫生之前，他是一位電機工程師，於是自行設計一套測電器。