In the bioelectric potential input interface system according to the present invention, a bioelectric potential of a user is measured by a sensor apparatus, an action of the user is determined from the bioelectric potential, and an action of an internal circuit of a device is controlled using a control signal that corresponds to the action of the user. The sensor apparatus has a plurality of electrode hollow bodies, measurement hollow bodies, and housing hollow bodies connected in a ring shape so as to be able to expand and contract. Each of the plurality of electrode hollow bodies has a measurement electrode. The measurement hollow bodies are connected by electroconductive wiring to the measurement electrodes and have a bioelectric potential measurement circuit for measuring a bioelectric potential of a user using the measurement electrodes. The housing hollow bodies have protrusions in the inside thereof. Wiring for connecting at least one measurement electrode and the bioelectric potential measurement circuit is provided on the periphery of each protrusion so as to have a length whereby the wiring can be fed in accordance with the amount of expansion when the sensor apparatus is expanded. The maximum separation distance (S) between mutually adjacent hollow bodies and housing hollow bodies is greater than the maximum separation distance (R) between two adjacent hollow bodies.Dans le système dinterface dentrée de potentiel bioélectrique selon la présente invention, un potentiel bioélectrique dun utilisateur est mesuré par un appareil de capteur, une action de lutilisateur est déterminée à partir du potentiel bioélectrique, et une action dun circuit interne dun dispositif est commandée à laide dun signal de commande qui correspond à laction de lutilisateur. Lappareil de capteur comprend une pluralité de corps creux délectrode, de corps creux de mesure et de corps creux de boîtier reliés de façon annulaire de façon à pouvoir sétendre et se contracter. Chacun de la pl
