Csem Centre Suisse D'electronique Et De Microtechnique Sa&#x2014;recherche Et D&#xe9;veloppement

Neroxis Sa

Olivier Chetelat

Josep Sola I Caros

Yves De Coulon

Marc Correvon

Marc Brodard

Emmanuel Onillon

Measurement device for measuring a bio-impedance and/or a bio-potential of a human or animal body and adapted to be worn on the body, including: at least two electrode sensors. Each of the at least two electrode sensors includes a first electrical contact configured to be in electrical contact with the skin of the body when the system is worn, and a second electrical contact. A single electrical connector electrically connects the at least two electrode sensors with each other via the second electrical contact. An active device is configured to cooperate with a subset of the at least two electrode sensors such that the potential of the electrical connector is substantially equal to a projected potential determined from the potential of the first electrical contact of each electrode sensor of the subset when the measurement device is worn.

Measurement device for measuring bio-impedance and/or a bio-potential of a human or animal body

A follower amplifier with power supply biased by a controlled voltage source such that the power supply potentials are, for the frequencies of interest, as close as possible to the potential of the follower output. There is proposed a front-end electronic circuit for biopotential and impedance measurements with outstanding performances (very high input impedance and gain very close to unity). Preferably, the explicit guard electrode and the explicit electronic unit at the belt are no longer necessary; all electronics is embedded in units placed directly at the measurement sites. Moreover, the proposed front-end electronic circuit allows a drastic simplification of the cabling and connectors since all units are connected to only one wire (the theoretical minimum) for potential reference and current return. Preferably, this wire does not even require an electrical isolation and can be easily embedded in the textile of a shirt, in a garment, mesh, belt, etc.

Floating front-end amplifier and one-wire measuring devices

A physical gas sensor of thermal type capable of determining the concentrations of a gas mixture even in the presence of humidity by measuring the thermal diffusivity and conductivity includes a cell with thermal conductivity whose frequency response to the gases is known, in particular in respect of humidity, delivering a signal Vm representative of the concentration of the gas. This cell is excited by a pulsed signal so that a processing can be carried out at different analysis frequencies: at low frequency and at higher frequency. The output signals from the two processing chains are combined in the circuit () so as to provide the levels of concentration of the gas and the concentration of the water vapour. The signals obtained may also be re-combined together with components of the signal Vm of various passbands.

Growing community of inventors

Hauterive, Switzerland

Olivier Chetelat