Electrode apparatus and measurement method thereof

A measurement method of an electrode apparatus, wherein the electrode apparatus is applied on a skin with hair of a mammal for measuring an electrical bio-signal, comprises:

• collecting hair in a bundle with an elongated structure, which is within a cylindrical chamber of the electrode apparatus, in response to rotation of the elongated structure for improving a contact of the at least one electrode, which is within the cylindrical chamber, with the skin of the mammal;
• where
• the electrode apparatus comprises one or more cylindrical chambers, and each of the elongated structure comprising a first portion parallel to a central axis of a cylindrical chamber within which the elongated structure is, a first end of the elongated structure being attached to a roof at a first end of a cylindrical chamber within which the elongated structure is, the first end of the elongated structure belonging to the first portion, and each of the elongated structure comprising at least one second portion, each comprising a second end opposite to the first end of the elongated structure, the at least one second portion of the elongated structure deviating from a direction of the central axis of a cylindrical chamber within which the elongated structure is;
• and each of the one or more cylindrical chambers comprise a wall, which forms a cavity within each of said one or more the cylindrical chambers, and each of the one or more cylindrical chambers comprise the at least one electrode, a second end of said one or more cylindrical chambers opposite to the first end being open.